2008-01-18 16:26:37

by Mark Brown

[permalink] [raw]
Subject: [UPDATED] WM97xx touchscreen drivers

This patch series adds support for the touchscreen controllers provided
by Wolfson Microelectronics WM97xx series chips in both polled and
streaming modes. It has been updated to reflect feedback since the
submission last week, most substantially in that the Makefile has been
cleaned up and the pxa-wm97xx has been renamed to mainstone-wm97xx to
better reflect how system-specific it is.


2008-01-18 16:27:28

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Add chip driver for WM9705 touchscreen

Signed-off-by: Liam Girdwood <[email protected]>
Signed-off-by: Graeme Gregory <[email protected]>
Signed-off-by: Mike Arthur <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Cc: Stanley Cai <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: Russell King <[email protected]>
Cc: Marc Kleine-Budde <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: Vince Sanders <[email protected]>
Cc: Andrew Zabolotny <[email protected]>
---
drivers/input/touchscreen/wm9705.c | 352 ++++++++++++++++++++++++++++++++++++
1 files changed, 352 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/wm9705.c

diff --git a/drivers/input/touchscreen/wm9705.c b/drivers/input/touchscreen/wm9705.c
new file mode 100644
index 0000000..f185104
--- /dev/null
+++ b/drivers/input/touchscreen/wm9705.c
@@ -0,0 +1,352 @@
+/*
+ * wm9705.c -- Codec driver for Wolfson WM9705 AC97 Codec.
+ *
+ * Copyright 2003, 2004, 2005, 2006, 2007 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ * [email protected] or [email protected]
+ * Parts Copyright : Ian Molton <[email protected]>
+ * Andrew Zabolotny <[email protected]>
+ * Russell King <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/wm97xx.h>
+
+#define TS_NAME "wm97xx"
+#define WM9705_VERSION "0.62"
+#define DEFAULT_PRESSURE 0xb0c0
+
+/*
+ * Module parameters
+ */
+
+/*
+ * Set current used for pressure measurement.
+ *
+ * Set pil = 2 to use 400uA
+ * pil = 1 to use 200uA and
+ * pil = 0 to disable pressure measurement.
+ *
+ * This is used to increase the range of values returned by the adc
+ * when measureing touchpanel pressure.
+ */
+static int pil;
+module_param(pil, int, 0);
+MODULE_PARM_DESC(pil, "Set current used for pressure measurement.");
+
+/*
+ * Set threshold for pressure measurement.
+ *
+ * Pen down pressure below threshold is ignored.
+ */
+static int pressure = DEFAULT_PRESSURE & 0xfff;
+module_param(pressure, int, 0);
+MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement.");
+
+/*
+ * Set adc sample delay.
+ *
+ * For accurate touchpanel measurements, some settling time may be
+ * required between the switch matrix applying a voltage across the
+ * touchpanel plate and the ADC sampling the signal.
+ *
+ * This delay can be set by setting delay = n, where n is the array
+ * position of the delay in the array delay_table below.
+ * Long delays > 1ms are supported for completeness, but are not
+ * recommended.
+ */
+static int delay = 4;
+module_param(delay, int, 0);
+MODULE_PARM_DESC(delay, "Set adc sample delay.");
+
+/*
+ * Pen detect comparator threshold.
+ *
+ * 0 to Vmid in 15 steps, 0 = use zero power comparator with Vmid threshold
+ * i.e. 1 = Vmid/15 threshold
+ * 15 = Vmid/1 threshold
+ *
+ * Adjust this value if you are having problems with pen detect not
+ * detecting any down events.
+ */
+static int pdd = 8;
+module_param(pdd, int, 0);
+MODULE_PARM_DESC(pdd, "Set pen detect comparator threshold");
+
+/*
+ * Set adc mask function.
+ *
+ * Sources of glitch noise, such as signals driving an LCD display, may feed
+ * through to the touch screen plates and affect measurement accuracy. In
+ * order to minimise this, a signal may be applied to the MASK pin to delay or
+ * synchronise the sampling.
+ *
+ * 0 = No delay or sync
+ * 1 = High on pin stops conversions
+ * 2 = Edge triggered, edge on pin delays conversion by delay param (above)
+ * 3 = Edge triggered, edge on pin starts conversion after delay param
+ */
+static int mask;
+module_param(mask, int, 0);
+MODULE_PARM_DESC(mask, "Set adc mask function.");
+
+/*
+ * ADC sample delay times in uS
+ */
+static const int delay_table[] = {
+ 21, /* 1 AC97 Link frames */
+ 42, /* 2 */
+ 84, /* 4 */
+ 167, /* 8 */
+ 333, /* 16 */
+ 667, /* 32 */
+ 1000, /* 48 */
+ 1333, /* 64 */
+ 2000, /* 96 */
+ 2667, /* 128 */
+ 3333, /* 160 */
+ 4000, /* 192 */
+ 4667, /* 224 */
+ 5333, /* 256 */
+ 6000, /* 288 */
+ 0 /* No delay, switch matrix always on */
+};
+
+/*
+ * Delay after issuing a POLL command.
+ *
+ * The delay is 3 AC97 link frames + the touchpanel settling delay
+ */
+static inline void poll_delay(int d)
+{
+ udelay(3 * AC97_LINK_FRAME + delay_table[d]);
+}
+
+/*
+ * set up the physical settings of the WM9705
+ */
+static void wm9705_phy_init(struct wm97xx *wm)
+{
+ u16 dig1 = 0, dig2 = WM97XX_RPR;
+
+ /*
+ * mute VIDEO and AUX as they share X and Y touchscreen
+ * inputs on the WM9705
+ */
+ wm97xx_reg_write(wm, AC97_AUX, 0x8000);
+ wm97xx_reg_write(wm, AC97_VIDEO, 0x8000);
+
+ /* touchpanel pressure current*/
+ if (pil == 2) {
+ dig2 |= WM9705_PIL;
+ dev_dbg(wm->dev,
+ "setting pressure measurement current to 400uA.");
+ } else if (pil)
+ dev_dbg(wm->dev,
+ "setting pressure measurement current to 200uA.");
+ if (!pil)
+ pressure = 0;
+
+ /* polling mode sample settling delay */
+ if (delay != 4) {
+ if (delay < 0 || delay > 15) {
+ dev_dbg(wm->dev, "supplied delay out of range.");
+ delay = 4;
+ }
+ }
+ dig1 &= 0xff0f;
+ dig1 |= WM97XX_DELAY(delay);
+ dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.",
+ delay_table[delay]);
+
+ /* WM9705 pdd */
+ dig2 |= (pdd & 0x000f);
+ dev_dbg(wm->dev, "setting pdd to Vmid/%d", 1 - (pdd & 0x000f));
+
+ /* mask */
+ dig2 |= ((mask & 0x3) << 4);
+
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
+}
+
+static void wm9705_dig_enable(struct wm97xx *wm, int enable)
+{
+ if (enable) {
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
+ wm->dig[2] | WM97XX_PRP_DET_DIG);
+ wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
+ } else
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
+ wm->dig[2] & ~WM97XX_PRP_DET_DIG);
+}
+
+static void wm9705_aux_prepare(struct wm97xx *wm)
+{
+ memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG);
+}
+
+static void wm9705_dig_restore(struct wm97xx *wm)
+{
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]);
+}
+
+static inline int is_pden(struct wm97xx *wm)
+{
+ return wm->dig[2] & WM9705_PDEN;
+}
+
+/*
+ * Read a sample from the WM9705 adc in polling mode.
+ */
+static int wm9705_poll_sample(struct wm97xx *wm, int adcsel, int *sample)
+{
+ int timeout = 5 * delay;
+
+ if (!wm->pen_probably_down) {
+ u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (!(data & WM97XX_PEN_DOWN))
+ return RC_PENUP;
+ wm->pen_probably_down = 1;
+ }
+
+ /* set up digitiser */
+ if (adcsel & 0x8000)
+ adcsel = ((adcsel & 0x7fff) + 3) << 12;
+
+ if (wm->mach_ops && wm->mach_ops->pre_sample)
+ wm->mach_ops->pre_sample(adcsel);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
+ adcsel | WM97XX_POLL | WM97XX_DELAY(delay));
+
+ /* wait 3 AC97 time slots + delay for conversion */
+ poll_delay(delay);
+
+ /* wait for POLL to go low */
+ while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
+ && timeout) {
+ udelay(AC97_LINK_FRAME);
+ timeout--;
+ }
+
+ if (timeout <= 0) {
+ /* If PDEN is set, we can get a timeout when pen goes up */
+ if (is_pden(wm))
+ wm->pen_probably_down = 0;
+ else
+ dev_dbg(wm->dev, "adc sample timeout");
+ return RC_PENUP;
+ }
+
+ *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (wm->mach_ops && wm->mach_ops->post_sample)
+ wm->mach_ops->post_sample(adcsel);
+
+ /* check we have correct sample */
+ if ((*sample & WM97XX_ADCSEL_MASK) != adcsel) {
+ dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel,
+ *sample & WM97XX_ADCSEL_MASK);
+ return RC_PENUP;
+ }
+
+ if (!(*sample & WM97XX_PEN_DOWN)) {
+ wm->pen_probably_down = 0;
+ return RC_PENUP;
+ }
+
+ return RC_VALID;
+}
+
+/*
+ * Sample the WM9705 touchscreen in polling mode
+ */
+static int wm9705_poll_touch(struct wm97xx *wm, struct wm97xx_data *data)
+{
+ int rc;
+
+ rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_X, &data->x);
+ if (rc != RC_VALID)
+ return rc;
+ rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_Y, &data->y);
+ if (rc != RC_VALID)
+ return rc;
+ if (pil) {
+ rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_PRES, &data->p);
+ if (rc != RC_VALID)
+ return rc;
+ } else
+ data->p = DEFAULT_PRESSURE;
+
+ return RC_VALID;
+}
+
+/*
+ * Enable WM9705 continuous mode, i.e. touch data is streamed across
+ * an AC97 slot
+ */
+static int wm9705_acc_enable(struct wm97xx *wm, int enable)
+{
+ u16 dig1, dig2;
+ int ret = 0;
+
+ dig1 = wm->dig[1];
+ dig2 = wm->dig[2];
+
+ if (enable) {
+ /* continous mode */
+ if (wm->mach_ops->acc_startup &&
+ (ret = wm->mach_ops->acc_startup(wm)) < 0)
+ return ret;
+ dig1 &= ~(WM97XX_CM_RATE_MASK | WM97XX_ADCSEL_MASK |
+ WM97XX_DELAY_MASK | WM97XX_SLT_MASK);
+ dig1 |= WM97XX_CTC | WM97XX_COO | WM97XX_SLEN |
+ WM97XX_DELAY(delay) |
+ WM97XX_SLT(wm->acc_slot) |
+ WM97XX_RATE(wm->acc_rate);
+ if (pil)
+ dig1 |= WM97XX_ADCSEL_PRES;
+ dig2 |= WM9705_PDEN;
+ } else {
+ dig1 &= ~(WM97XX_CTC | WM97XX_COO | WM97XX_SLEN);
+ dig2 &= ~WM9705_PDEN;
+ if (wm->mach_ops->acc_shutdown)
+ wm->mach_ops->acc_shutdown(wm);
+ }
+
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
+ return ret;
+}
+
+struct wm97xx_codec_drv wm9705_codec = {
+ .id = WM9705_ID2,
+ .name = "wm9705",
+ .poll_sample = wm9705_poll_sample,
+ .poll_touch = wm9705_poll_touch,
+ .acc_enable = wm9705_acc_enable,
+ .phy_init = wm9705_phy_init,
+ .dig_enable = wm9705_dig_enable,
+ .dig_restore = wm9705_dig_restore,
+ .aux_prepare = wm9705_aux_prepare,
+};
+EXPORT_SYMBOL_GPL(wm9705_codec);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <[email protected]>");
+MODULE_DESCRIPTION("WM9705 Touch Screen Driver");
+MODULE_LICENSE("GPL");
--
1.5.3.8

2008-01-18 16:27:40

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Build system and MAINTAINERS entry for WM97xx touchscreen drivers

Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Liam Girdwood <[email protected]>
Cc: Sam Ravnborg <[email protected]>
---
MAINTAINERS | 9 ++++++
drivers/input/touchscreen/Kconfig | 52 ++++++++++++++++++++++++++++++++++++
drivers/input/touchscreen/Makefile | 7 +++++
3 files changed, 68 insertions(+), 0 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 2340cfb..4ad793f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4204,6 +4204,15 @@ L: [email protected]
W: http://oops.ghostprotocols.net:81/blog
S: Maintained

+WM97XX TOUCHSCREEN DRIVERS
+P: Mark Brown
+M: [email protected]
+P: Liam Girdwood
+M: [email protected]
+L: [email protected]
+T: git git://opensource.wolfsonmicro.com/linux-2.6-touch
+S: Supported
+
X.25 NETWORK LAYER
P: Henner Eisen
M: [email protected]
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 90e8e92..0be05a2 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -158,6 +158,58 @@ config TOUCHSCREEN_TOUCHRIGHT
To compile this driver as a module, choose M here: the
module will be called touchright.

+config TOUCHSCREEN_WM97XX
+ tristate "Support for WM97xx AC97 touchscreen controllers"
+ depends on AC97_BUS
+
+config TOUCHSCREEN_WM9705
+ bool "WM9705 Touchscreen interface support"
+ depends on TOUCHSCREEN_WM97XX
+ help
+ Say Y here if you have a Wolfson Microelectronics WM9705 touchscreen
+ controller connected to your system.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called wm9705.
+
+config TOUCHSCREEN_WM9712
+ bool "WM9712 Touchscreen interface support"
+ depends on TOUCHSCREEN_WM97XX
+ help
+ Say Y here if you have a Wolfson Microelectronics WM9712 touchscreen
+ controller connected to your system.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called wm9712.
+
+config TOUCHSCREEN_WM9713
+ bool "WM9713 Touchscreen interface support"
+ depends on TOUCHSCREEN_WM97XX
+ help
+ Say Y here if you have a Wolfson Microelectronics WM9713 touchscreen
+ controller connected to your system.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called wm9713.
+
+config TOUCHSCREEN_WM97XX_MAINSTONE
+ tristate "WM97xx Mainstone accelerated touch"
+ depends on TOUCHSCREEN_WM97XX && ARCH_PXA
+ help
+ Say Y here for support for streaming mode with WM97xx touchscreens
+ on Mainstone systems.
+
+ If unsure, say N
+
+ To compile this driver as a module, choose M here: the
+ module will be called mainstone-wm97xx
+
config TOUCHSCREEN_TOUCHWIN
tristate "Touchwin serial touchscreen"
select SERIO
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 35d4097..d38156e 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -4,6 +4,8 @@

# Each configuration option enables a list of files.

+wm97xx-ts-y := wm97xx-core.o
+
obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
obj-$(CONFIG_TOUCHSCREEN_BITSY) += h3600_ts_input.o
obj-$(CONFIG_TOUCHSCREEN_CORGI) += corgi_ts.o
@@ -19,3 +21,8 @@ obj-$(CONFIG_TOUCHSCREEN_PENMOUNT) += penmount.o
obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT) += touchright.o
obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o
obj-$(CONFIG_TOUCHSCREEN_UCB1400) += ucb1400_ts.o
+obj-$(CONFIG_TOUCHSCREEN_WM97XX) += wm97xx-ts.o
+obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) += mainstone-wm97xx.o
+wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9705) += wm9705.o
+wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9712) += wm9712.o
+wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9713) += wm9713.o
--
1.5.3.8

2008-01-18 16:27:55

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Driver for WM97xx touchscreens in streaming mode on Mainstone

Signed-off-by: Liam Girdwood <[email protected]>
Signed-off-by: Graeme Gregory <[email protected]>
Signed-off-by: Mike Arthur <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Cc: Stanley Cai <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: Russell King <[email protected]>
Cc: Marc Kleine-Budde <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: Vince Sanders <[email protected]>
Cc: Andrew Zabolotny <[email protected]>
---
drivers/input/touchscreen/mainstone-wm97xx.c | 298 ++++++++++++++++++++++++++
1 files changed, 298 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/mainstone-wm97xx.c

diff --git a/drivers/input/touchscreen/mainstone-wm97xx.c b/drivers/input/touchscreen/mainstone-wm97xx.c
new file mode 100644
index 0000000..1d2b3f1
--- /dev/null
+++ b/drivers/input/touchscreen/mainstone-wm97xx.c
@@ -0,0 +1,298 @@
+/*
+ * mainstone-wm97xx.c -- Mainstone Continuous Touch screen driver for
+ * Wolfson WM97xx AC97 Codecs.
+ *
+ * Copyright 2004, 2007 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ * [email protected] or [email protected]
+ * Parts Copyright : Ian Molton <[email protected]>
+ * Andrew Zabolotny <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * Notes:
+ * This is a wm97xx extended touch driver to capture touch
+ * data in a continuous manner on the Intel XScale archictecture
+ *
+ * Features:
+ * - codecs supported:- WM9705, WM9712, WM9713
+ * - processors supported:- Intel XScale PXA25x, PXA26x, PXA27x
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/wm97xx.h>
+#include <linux/io.h>
+#include <asm/arch/pxa-regs.h>
+
+#define VERSION "0.13"
+
+struct continuous {
+ u16 id; /* codec id */
+ u8 code; /* continuous code */
+ u8 reads; /* number of coord reads per read cycle */
+ u32 speed; /* number of coords per second */
+};
+
+#define WM_READS(sp) ((sp / HZ) + 1)
+
+static const struct continuous cinfo[] = {
+ {WM9705_ID2, 0, WM_READS(94), 94},
+ {WM9705_ID2, 1, WM_READS(188), 188},
+ {WM9705_ID2, 2, WM_READS(375), 375},
+ {WM9705_ID2, 3, WM_READS(750), 750},
+ {WM9712_ID2, 0, WM_READS(94), 94},
+ {WM9712_ID2, 1, WM_READS(188), 188},
+ {WM9712_ID2, 2, WM_READS(375), 375},
+ {WM9712_ID2, 3, WM_READS(750), 750},
+ {WM9713_ID2, 0, WM_READS(94), 94},
+ {WM9713_ID2, 1, WM_READS(120), 120},
+ {WM9713_ID2, 2, WM_READS(154), 154},
+ {WM9713_ID2, 3, WM_READS(188), 188},
+};
+
+/* continuous speed index */
+static int sp_idx;
+static u16 last, tries;
+
+/*
+ * Pen sampling frequency (Hz) in continuous mode.
+ */
+static int cont_rate = 200;
+module_param(cont_rate, int, 0);
+MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");
+
+/*
+ * Pen down detection.
+ *
+ * This driver can either poll or use an interrupt to indicate a pen down
+ * event. If the irq request fails then it will fall back to polling mode.
+ */
+static int pen_int;
+module_param(pen_int, int, 0);
+MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");
+
+/*
+ * Pressure readback.
+ *
+ * Set to 1 to read back pen down pressure
+ */
+static int pressure;
+module_param(pressure, int, 0);
+MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");
+
+/*
+ * AC97 touch data slot.
+ *
+ * Touch screen readback data ac97 slot
+ */
+static int ac97_touch_slot = 5;
+module_param(ac97_touch_slot, int, 0);
+MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");
+
+
+/* flush AC97 slot 5 FIFO on pxa machines */
+#ifdef CONFIG_PXA27x
+static void wm97xx_acc_pen_up(struct wm97xx *wm)
+{
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(1);
+
+ while (MISR & (1 << 2))
+ MODR;
+}
+#else
+static void wm97xx_acc_pen_up(struct wm97xx *wm)
+{
+ int count = 16;
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(1);
+
+ while (count < 16) {
+ MODR;
+ count--;
+ }
+}
+#endif
+
+static int wm97xx_acc_pen_down(struct wm97xx *wm)
+{
+ u16 x, y, p = 0x100 | WM97XX_ADCSEL_PRES;
+ int reads = 0;
+
+ /* data is never immediately available after pen down irq */
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(1);
+
+ if (tries > 5) {
+ tries = 0;
+ return RC_PENUP;
+ }
+
+ x = MODR;
+ if (x == last) {
+ tries++;
+ return RC_AGAIN;
+ }
+ last = x;
+ do {
+ if (reads)
+ x = MODR;
+ y = MODR;
+ if (pressure)
+ p = MODR;
+
+ /* are samples valid */
+ if ((x & 0x7000) != WM97XX_ADCSEL_X ||
+ (y & 0x7000) != WM97XX_ADCSEL_Y ||
+ (p & 0x7000) != WM97XX_ADCSEL_PRES)
+ goto up;
+
+ /* coordinate is good */
+ tries = 0;
+ input_report_abs(wm->input_dev, ABS_X, x & 0xfff);
+ input_report_abs(wm->input_dev, ABS_Y, y & 0xfff);
+ input_report_abs(wm->input_dev, ABS_PRESSURE, p & 0xfff);
+ input_sync(wm->input_dev);
+ reads++;
+ } while (reads < cinfo[sp_idx].reads);
+up:
+ return RC_PENDOWN | RC_AGAIN;
+}
+
+static int wm97xx_acc_startup(struct wm97xx *wm)
+{
+ int idx = 0;
+
+ /* check we have a codec */
+ if (wm->ac97 == NULL)
+ return -ENODEV;
+
+ /* Go you big red fire engine */
+ for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
+ if (wm->id != cinfo[idx].id)
+ continue;
+ sp_idx = idx;
+ if (cont_rate <= cinfo[idx].speed)
+ break;
+ }
+ wm->acc_rate = cinfo[sp_idx].code;
+ wm->acc_slot = ac97_touch_slot;
+ dev_info(wm->dev,
+ "mainstone accelerated touchscreen driver, %d samples/sec\n",
+ cinfo[sp_idx].speed);
+
+ /* codec specific irq config */
+ if (pen_int) {
+ switch (wm->id) {
+ case WM9705_ID2:
+ wm->pen_irq = IRQ_GPIO(4);
+ set_irq_type(IRQ_GPIO(4), IRQT_BOTHEDGE);
+ break;
+ case WM9712_ID2:
+ case WM9713_ID2:
+ /* enable pen down interrupt */
+ /* use PEN_DOWN GPIO 13 to assert IRQ on GPIO line 2 */
+ wm->pen_irq = MAINSTONE_AC97_IRQ;
+ wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
+ WM97XX_GPIO_POL_HIGH,
+ WM97XX_GPIO_STICKY,
+ WM97XX_GPIO_WAKE);
+ wm97xx_config_gpio(wm, WM97XX_GPIO_2, WM97XX_GPIO_OUT,
+ WM97XX_GPIO_POL_HIGH,
+ WM97XX_GPIO_NOTSTICKY,
+ WM97XX_GPIO_NOWAKE);
+ break;
+ default:
+ dev_err(wm->dev,
+ "pen down irq not supported on this device\n");
+ pen_int = 0;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static void wm97xx_acc_shutdown(struct wm97xx *wm)
+{
+ /* codec specific deconfig */
+ if (pen_int) {
+ switch (wm->id & 0xffff) {
+ case WM9705_ID2:
+ wm->pen_irq = 0;
+ break;
+ case WM9712_ID2:
+ case WM9713_ID2:
+ /* disable interrupt */
+ wm->pen_irq = 0;
+ break;
+ }
+ }
+}
+
+static void wm97xx_irq_enable(struct wm97xx *wm, int enable)
+{
+ if (enable)
+ enable_irq(wm->pen_irq);
+ else
+ disable_irq(wm->pen_irq);
+}
+
+static struct wm97xx_mach_ops mainstone_mach_ops = {
+ .acc_enabled = 1,
+ .acc_pen_up = wm97xx_acc_pen_up,
+ .acc_pen_down = wm97xx_acc_pen_down,
+ .acc_startup = wm97xx_acc_startup,
+ .acc_shutdown = wm97xx_acc_shutdown,
+ .irq_enable = wm97xx_irq_enable,
+};
+
+static int mainstone_wm97xx_probe(struct device *dev)
+{
+ struct wm97xx *wm = dev->driver_data;
+ return wm97xx_register_mach_ops(wm, &mainstone_mach_ops);
+}
+
+static int mainstone_wm97xx_remove(struct device *dev)
+{
+ struct wm97xx *wm = dev->driver_data;
+ wm97xx_unregister_mach_ops(wm);
+ return 0;
+}
+
+static struct device_driver mainstone_wm97xx_driver = {
+ .name = "wm97xx-touchscreen",
+ .bus = &wm97xx_bus_type,
+ .owner = THIS_MODULE,
+ .probe = mainstone_wm97xx_probe,
+ .remove = mainstone_wm97xx_remove
+};
+
+static int __init mainstone_wm97xx_init(void)
+{
+ return driver_register(&mainstone_wm97xx_driver);
+}
+
+static void __exit mainstone_wm97xx_exit(void)
+{
+ driver_unregister(&mainstone_wm97xx_driver);
+}
+
+module_init(mainstone_wm97xx_init);
+module_exit(mainstone_wm97xx_exit);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <[email protected]>");
+MODULE_DESCRIPTION("wm97xx continuous touch driver for mainstone");
+MODULE_LICENSE("GPL");
--
1.5.3.8

2008-01-18 16:28:23

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Add chip driver for WM9712 touchscreen

Signed-off-by: Liam Girdwood <[email protected]>
Signed-off-by: Graeme Gregory <[email protected]>
Signed-off-by: Mike Arthur <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Cc: Stanley Cai <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: Russell King <[email protected]>
Cc: Marc Kleine-Budde <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: Vince Sanders <[email protected]>
Cc: Andrew Zabolotny <[email protected]>
---
drivers/input/touchscreen/wm9712.c | 461 ++++++++++++++++++++++++++++++++++++
1 files changed, 461 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/wm9712.c

diff --git a/drivers/input/touchscreen/wm9712.c b/drivers/input/touchscreen/wm9712.c
new file mode 100644
index 0000000..eaab326
--- /dev/null
+++ b/drivers/input/touchscreen/wm9712.c
@@ -0,0 +1,461 @@
+/*
+ * wm9712.c -- Codec driver for Wolfson WM9712 AC97 Codecs.
+ *
+ * Copyright 2003, 2004, 2005, 2006, 2007 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ * [email protected] or [email protected]
+ * Parts Copyright : Ian Molton <[email protected]>
+ * Andrew Zabolotny <[email protected]>
+ * Russell King <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/wm97xx.h>
+
+#define TS_NAME "wm97xx"
+#define WM9712_VERSION "0.61"
+#define DEFAULT_PRESSURE 0xb0c0
+
+/*
+ * Module parameters
+ */
+
+/*
+ * Set internal pull up for pen detect.
+ *
+ * Pull up is in the range 1.02k (least sensitive) to 64k (most sensitive)
+ * i.e. pull up resistance = 64k Ohms / rpu.
+ *
+ * Adjust this value if you are having problems with pen detect not
+ * detecting any down event.
+ */
+static int rpu = 8;
+module_param(rpu, int, 0);
+MODULE_PARM_DESC(rpu, "Set internal pull up resitor for pen detect.");
+
+/*
+ * Set current used for pressure measurement.
+ *
+ * Set pil = 2 to use 400uA
+ * pil = 1 to use 200uA and
+ * pil = 0 to disable pressure measurement.
+ *
+ * This is used to increase the range of values returned by the adc
+ * when measureing touchpanel pressure.
+ */
+static int pil;
+module_param(pil, int, 0);
+MODULE_PARM_DESC(pil, "Set current used for pressure measurement.");
+
+/*
+ * Set threshold for pressure measurement.
+ *
+ * Pen down pressure below threshold is ignored.
+ */
+static int pressure = DEFAULT_PRESSURE & 0xfff;
+module_param(pressure, int, 0);
+MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement.");
+
+/*
+ * Set adc sample delay.
+ *
+ * For accurate touchpanel measurements, some settling time may be
+ * required between the switch matrix applying a voltage across the
+ * touchpanel plate and the ADC sampling the signal.
+ *
+ * This delay can be set by setting delay = n, where n is the array
+ * position of the delay in the array delay_table below.
+ * Long delays > 1ms are supported for completeness, but are not
+ * recommended.
+ */
+static int delay = 3;
+module_param(delay, int, 0);
+MODULE_PARM_DESC(delay, "Set adc sample delay.");
+
+/*
+ * Set five_wire = 1 to use a 5 wire touchscreen.
+ *
+ * NOTE: Five wire mode does not allow for readback of pressure.
+ */
+static int five_wire;
+module_param(five_wire, int, 0);
+MODULE_PARM_DESC(five_wire, "Set to '1' to use 5-wire touchscreen.");
+
+/*
+ * Set adc mask function.
+ *
+ * Sources of glitch noise, such as signals driving an LCD display, may feed
+ * through to the touch screen plates and affect measurement accuracy. In
+ * order to minimise this, a signal may be applied to the MASK pin to delay or
+ * synchronise the sampling.
+ *
+ * 0 = No delay or sync
+ * 1 = High on pin stops conversions
+ * 2 = Edge triggered, edge on pin delays conversion by delay param (above)
+ * 3 = Edge triggered, edge on pin starts conversion after delay param
+ */
+static int mask;
+module_param(mask, int, 0);
+MODULE_PARM_DESC(mask, "Set adc mask function.");
+
+/*
+ * Coordinate Polling Enable.
+ *
+ * Set to 1 to enable coordinate polling. e.g. x,y[,p] is sampled together
+ * for every poll.
+ */
+static int coord;
+module_param(coord, int, 0);
+MODULE_PARM_DESC(coord, "Polling coordinate mode");
+
+/*
+ * ADC sample delay times in uS
+ */
+static const int delay_table[] = {
+ 21, /* 1 AC97 Link frames */
+ 42, /* 2 */
+ 84, /* 4 */
+ 167, /* 8 */
+ 333, /* 16 */
+ 667, /* 32 */
+ 1000, /* 48 */
+ 1333, /* 64 */
+ 2000, /* 96 */
+ 2667, /* 128 */
+ 3333, /* 160 */
+ 4000, /* 192 */
+ 4667, /* 224 */
+ 5333, /* 256 */
+ 6000, /* 288 */
+ 0 /* No delay, switch matrix always on */
+};
+
+/*
+ * Delay after issuing a POLL command.
+ *
+ * The delay is 3 AC97 link frames + the touchpanel settling delay
+ */
+static inline void poll_delay(int d)
+{
+ udelay(3 * AC97_LINK_FRAME + delay_table[d]);
+}
+
+/*
+ * set up the physical settings of the WM9712
+ */
+static void wm9712_phy_init(struct wm97xx *wm)
+{
+ u16 dig1 = 0;
+ u16 dig2 = WM97XX_RPR | WM9712_RPU(1);
+
+ /* WM9712 rpu */
+ if (rpu) {
+ dig2 &= 0xffc0;
+ dig2 |= WM9712_RPU(rpu);
+ dev_dbg(wm->dev, "setting pen detect pull-up to %d Ohms",
+ 64000 / rpu);
+ }
+
+ /* touchpanel pressure current*/
+ if (pil == 2) {
+ dig2 |= WM9712_PIL;
+ dev_dbg(wm->dev,
+ "setting pressure measurement current to 400uA.");
+ } else if (pil)
+ dev_dbg(wm->dev,
+ "setting pressure measurement current to 200uA.");
+ if (!pil)
+ pressure = 0;
+
+ /* WM9712 five wire */
+ if (five_wire) {
+ dig2 |= WM9712_45W;
+ dev_dbg(wm->dev, "setting 5-wire touchscreen mode.");
+ }
+
+ /* polling mode sample settling delay */
+ if (delay < 0 || delay > 15) {
+ dev_dbg(wm->dev, "supplied delay out of range.");
+ delay = 4;
+ }
+ dig1 &= 0xff0f;
+ dig1 |= WM97XX_DELAY(delay);
+ dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.",
+ delay_table[delay]);
+
+ /* mask */
+ dig2 |= ((mask & 0x3) << 6);
+ if (mask) {
+ u16 reg;
+ /* Set GPIO4 as Mask Pin*/
+ reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
+ wm97xx_reg_write(wm, AC97_MISC_AFE, reg | WM97XX_GPIO_4);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
+ wm97xx_reg_write(wm, AC97_GPIO_CFG, reg | WM97XX_GPIO_4);
+ }
+
+ /* wait - coord mode */
+ if (coord)
+ dig2 |= WM9712_WAIT;
+
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
+}
+
+static void wm9712_dig_enable(struct wm97xx *wm, int enable)
+{
+ u16 dig2 = wm->dig[2];
+
+ if (enable) {
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
+ dig2 | WM97XX_PRP_DET_DIG);
+ wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
+ } else
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
+ dig2 & ~WM97XX_PRP_DET_DIG);
+}
+
+static void wm9712_aux_prepare(struct wm97xx *wm)
+{
+ memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG);
+}
+
+static void wm9712_dig_restore(struct wm97xx *wm)
+{
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]);
+}
+
+static inline int is_pden(struct wm97xx *wm)
+{
+ return wm->dig[2] & WM9712_PDEN;
+}
+
+/*
+ * Read a sample from the WM9712 adc in polling mode.
+ */
+static int wm9712_poll_sample(struct wm97xx *wm, int adcsel, int *sample)
+{
+ int timeout = 5 * delay;
+
+ if (!wm->pen_probably_down) {
+ u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (!(data & WM97XX_PEN_DOWN))
+ return RC_PENUP;
+ wm->pen_probably_down = 1;
+ }
+
+ /* set up digitiser */
+ if (adcsel & 0x8000)
+ adcsel = ((adcsel & 0x7fff) + 3) << 12;
+
+ if (wm->mach_ops && wm->mach_ops->pre_sample)
+ wm->mach_ops->pre_sample(adcsel);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
+ adcsel | WM97XX_POLL | WM97XX_DELAY(delay));
+
+ /* wait 3 AC97 time slots + delay for conversion */
+ poll_delay(delay);
+
+ /* wait for POLL to go low */
+ while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
+ && timeout) {
+ udelay(AC97_LINK_FRAME);
+ timeout--;
+ }
+
+ if (timeout <= 0) {
+ /* If PDEN is set, we can get a timeout when pen goes up */
+ if (is_pden(wm))
+ wm->pen_probably_down = 0;
+ else
+ dev_dbg(wm->dev, "adc sample timeout");
+ return RC_PENUP;
+ }
+
+ *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (wm->mach_ops && wm->mach_ops->post_sample)
+ wm->mach_ops->post_sample(adcsel);
+
+ /* check we have correct sample */
+ if ((*sample & WM97XX_ADCSEL_MASK) != adcsel) {
+ dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel,
+ *sample & WM97XX_ADCSEL_MASK);
+ return RC_PENUP;
+ }
+
+ if (!(*sample & WM97XX_PEN_DOWN)) {
+ wm->pen_probably_down = 0;
+ return RC_PENUP;
+ }
+
+ return RC_VALID;
+}
+
+/*
+ * Read a coord from the WM9712 adc in polling mode.
+ */
+static int wm9712_poll_coord(struct wm97xx *wm, struct wm97xx_data *data)
+{
+ int timeout = 5 * delay;
+
+ if (!wm->pen_probably_down) {
+ u16 data_rd = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (!(data_rd & WM97XX_PEN_DOWN))
+ return RC_PENUP;
+ wm->pen_probably_down = 1;
+ }
+
+ /* set up digitiser */
+ if (wm->mach_ops && wm->mach_ops->pre_sample)
+ wm->mach_ops->pre_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);
+
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1,
+ WM97XX_COO | WM97XX_POLL | WM97XX_DELAY(delay));
+
+ /* wait 3 AC97 time slots + delay for conversion and read x */
+ poll_delay(delay);
+ data->x = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ /* wait for POLL to go low */
+ while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL)
+ && timeout) {
+ udelay(AC97_LINK_FRAME);
+ timeout--;
+ }
+
+ if (timeout <= 0) {
+ /* If PDEN is set, we can get a timeout when pen goes up */
+ if (is_pden(wm))
+ wm->pen_probably_down = 0;
+ else
+ dev_dbg(wm->dev, "adc sample timeout");
+ return RC_PENUP;
+ }
+
+ /* read back y data */
+ data->y = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (pil)
+ data->p = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ else
+ data->p = DEFAULT_PRESSURE;
+
+ if (wm->mach_ops && wm->mach_ops->post_sample)
+ wm->mach_ops->post_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);
+
+ /* check we have correct sample */
+ if (!(data->x & WM97XX_ADCSEL_X) || !(data->y & WM97XX_ADCSEL_Y))
+ goto err;
+ if (pil && !(data->p & WM97XX_ADCSEL_PRES))
+ goto err;
+
+ if (!(data->x & WM97XX_PEN_DOWN)) {
+ wm->pen_probably_down = 0;
+ return RC_PENUP;
+ }
+ return RC_VALID;
+err:
+ return RC_PENUP;
+}
+
+/*
+ * Sample the WM9712 touchscreen in polling mode
+ */
+static int wm9712_poll_touch(struct wm97xx *wm, struct wm97xx_data *data)
+{
+ int rc;
+
+ if (coord) {
+ rc = wm9712_poll_coord(wm, data);
+ if (rc != RC_VALID)
+ return rc;
+ } else {
+ rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_X, &data->x);
+ if (rc != RC_VALID)
+ return rc;
+
+ rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_Y, &data->y);
+ if (rc != RC_VALID)
+ return rc;
+
+ if (pil && !five_wire) {
+ rc = wm9712_poll_sample(wm, WM97XX_ADCSEL_PRES,
+ &data->p);
+ if (rc != RC_VALID)
+ return rc;
+ } else
+ data->p = DEFAULT_PRESSURE;
+ }
+ return RC_VALID;
+}
+
+/*
+ * Enable WM9712 continuous mode, i.e. touch data is streamed across
+ * an AC97 slot
+ */
+static int wm9712_acc_enable(struct wm97xx *wm, int enable)
+{
+ u16 dig1, dig2;
+ int ret = 0;
+
+ dig1 = wm->dig[1];
+ dig2 = wm->dig[2];
+
+ if (enable) {
+ /* continous mode */
+ if (wm->mach_ops->acc_startup) {
+ ret = wm->mach_ops->acc_startup(wm);
+ if (ret < 0)
+ return ret;
+ }
+ dig1 &= ~(WM97XX_CM_RATE_MASK | WM97XX_ADCSEL_MASK |
+ WM97XX_DELAY_MASK | WM97XX_SLT_MASK);
+ dig1 |= WM97XX_CTC | WM97XX_COO | WM97XX_SLEN |
+ WM97XX_DELAY(delay) |
+ WM97XX_SLT(wm->acc_slot) |
+ WM97XX_RATE(wm->acc_rate);
+ if (pil)
+ dig1 |= WM97XX_ADCSEL_PRES;
+ dig2 |= WM9712_PDEN;
+ } else {
+ dig1 &= ~(WM97XX_CTC | WM97XX_COO | WM97XX_SLEN);
+ dig2 &= ~WM9712_PDEN;
+ if (wm->mach_ops->acc_shutdown)
+ wm->mach_ops->acc_shutdown(wm);
+ }
+
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
+ wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
+ return 0;
+}
+
+struct wm97xx_codec_drv wm9712_codec = {
+ .id = WM9712_ID2,
+ .name = "wm9712",
+ .poll_sample = wm9712_poll_sample,
+ .poll_touch = wm9712_poll_touch,
+ .acc_enable = wm9712_acc_enable,
+ .phy_init = wm9712_phy_init,
+ .dig_enable = wm9712_dig_enable,
+ .dig_restore = wm9712_dig_restore,
+ .aux_prepare = wm9712_aux_prepare,
+};
+EXPORT_SYMBOL_GPL(wm9712_codec);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <[email protected]>");
+MODULE_DESCRIPTION("WM9712 Touch Screen Driver");
+MODULE_LICENSE("GPL");
--
1.5.3.8

2008-01-18 16:28:36

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Add chip driver for WM9713 touchscreen

Signed-off-by: Liam Girdwood <[email protected]>
Signed-off-by: Graeme Gregory <[email protected]>
Signed-off-by: Mike Arthur <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Cc: Stanley Cai <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: Russell King <[email protected]>
Cc: Marc Kleine-Budde <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: Vince Sanders <[email protected]>
Cc: Andrew Zabolotny <[email protected]>
---
drivers/input/touchscreen/wm9713.c | 459 ++++++++++++++++++++++++++++++++++++
1 files changed, 459 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/wm9713.c

diff --git a/drivers/input/touchscreen/wm9713.c b/drivers/input/touchscreen/wm9713.c
new file mode 100644
index 0000000..5067e59
--- /dev/null
+++ b/drivers/input/touchscreen/wm9713.c
@@ -0,0 +1,459 @@
+/*
+ * wm9713.c -- Codec touch driver for Wolfson WM9713 AC97 Codec.
+ *
+ * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ * [email protected] or [email protected]
+ * Parts Copyright : Ian Molton <[email protected]>
+ * Andrew Zabolotny <[email protected]>
+ * Russell King <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/wm97xx.h>
+
+#define TS_NAME "wm97xx"
+#define WM9713_VERSION "0.53"
+#define DEFAULT_PRESSURE 0xb0c0
+
+/*
+ * Module parameters
+ */
+
+/*
+ * Set internal pull up for pen detect.
+ *
+ * Pull up is in the range 1.02k (least sensitive) to 64k (most sensitive)
+ * i.e. pull up resistance = 64k Ohms / rpu.
+ *
+ * Adjust this value if you are having problems with pen detect not
+ * detecting any down event.
+ */
+static int rpu = 8;
+module_param(rpu, int, 0);
+MODULE_PARM_DESC(rpu, "Set internal pull up resitor for pen detect.");
+
+/*
+ * Set current used for pressure measurement.
+ *
+ * Set pil = 2 to use 400uA
+ * pil = 1 to use 200uA and
+ * pil = 0 to disable pressure measurement.
+ *
+ * This is used to increase the range of values returned by the adc
+ * when measureing touchpanel pressure.
+ */
+static int pil;
+module_param(pil, int, 0);
+MODULE_PARM_DESC(pil, "Set current used for pressure measurement.");
+
+/*
+ * Set threshold for pressure measurement.
+ *
+ * Pen down pressure below threshold is ignored.
+ */
+static int pressure = DEFAULT_PRESSURE & 0xfff;
+module_param(pressure, int, 0);
+MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement.");
+
+/*
+ * Set adc sample delay.
+ *
+ * For accurate touchpanel measurements, some settling time may be
+ * required between the switch matrix applying a voltage across the
+ * touchpanel plate and the ADC sampling the signal.
+ *
+ * This delay can be set by setting delay = n, where n is the array
+ * position of the delay in the array delay_table below.
+ * Long delays > 1ms are supported for completeness, but are not
+ * recommended.
+ */
+static int delay = 4;
+module_param(delay, int, 0);
+MODULE_PARM_DESC(delay, "Set adc sample delay.");
+
+/*
+ * Set adc mask function.
+ *
+ * Sources of glitch noise, such as signals driving an LCD display, may feed
+ * through to the touch screen plates and affect measurement accuracy. In
+ * order to minimise this, a signal may be applied to the MASK pin to delay or
+ * synchronise the sampling.
+ *
+ * 0 = No delay or sync
+ * 1 = High on pin stops conversions
+ * 2 = Edge triggered, edge on pin delays conversion by delay param (above)
+ * 3 = Edge triggered, edge on pin starts conversion after delay param
+ */
+static int mask;
+module_param(mask, int, 0);
+MODULE_PARM_DESC(mask, "Set adc mask function.");
+
+/*
+ * Coordinate Polling Enable.
+ *
+ * Set to 1 to enable coordinate polling. e.g. x,y[,p] is sampled together
+ * for every poll.
+ */
+static int coord;
+module_param(coord, int, 0);
+MODULE_PARM_DESC(coord, "Polling coordinate mode");
+
+/*
+ * ADC sample delay times in uS
+ */
+static const int delay_table[] = {
+ 21, /* 1 AC97 Link frames */
+ 42, /* 2 */
+ 84, /* 4 */
+ 167, /* 8 */
+ 333, /* 16 */
+ 667, /* 32 */
+ 1000, /* 48 */
+ 1333, /* 64 */
+ 2000, /* 96 */
+ 2667, /* 128 */
+ 3333, /* 160 */
+ 4000, /* 192 */
+ 4667, /* 224 */
+ 5333, /* 256 */
+ 6000, /* 288 */
+ 0 /* No delay, switch matrix always on */
+};
+
+/*
+ * Delay after issuing a POLL command.
+ *
+ * The delay is 3 AC97 link frames + the touchpanel settling delay
+ */
+static inline void poll_delay(int d)
+{
+ udelay(3 * AC97_LINK_FRAME + delay_table[d]);
+}
+
+/*
+ * set up the physical settings of the WM9713
+ */
+static void wm9713_phy_init(struct wm97xx *wm)
+{
+ u16 dig1 = 0, dig2, dig3;
+
+ /* default values */
+ dig2 = WM97XX_DELAY(4) | WM97XX_SLT(5);
+ dig3 = WM9712_RPU(1);
+
+ /* rpu */
+ if (rpu) {
+ dig3 &= 0xffc0;
+ dig3 |= WM9712_RPU(rpu);
+ dev_info(wm->dev, "setting pen detect pull-up to %d Ohms\n",
+ 64000 / rpu);
+ }
+
+ /* touchpanel pressure */
+ if (pil == 2) {
+ dig3 |= WM9712_PIL;
+ dev_info(wm->dev,
+ "setting pressure measurement current to 400uA.");
+ } else if (pil)
+ dev_info(wm->dev,
+ "setting pressure measurement current to 200uA.");
+ if (!pil)
+ pressure = 0;
+
+ /* sample settling delay */
+ if (delay < 0 || delay > 15) {
+ dev_info(wm->dev, "supplied delay out of range.");
+ delay = 4;
+ dev_info(wm->dev, "setting adc sample delay to %d u Secs.",
+ delay_table[delay]);
+ }
+ dig2 &= 0xff0f;
+ dig2 |= WM97XX_DELAY(delay);
+
+ /* mask */
+ dig3 |= ((mask & 0x3) << 4);
+ if (coord)
+ dig3 |= WM9713_WAIT;
+
+ wm->misc = wm97xx_reg_read(wm, 0x5a);
+
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG2, dig2);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, dig3);
+ wm97xx_reg_write(wm, AC97_GPIO_STICKY, 0x0);
+}
+
+static void wm9713_dig_enable(struct wm97xx *wm, int enable)
+{
+ u16 val;
+
+ if (enable) {
+ val = wm97xx_reg_read(wm, AC97_EXTENDED_MID);
+ wm97xx_reg_write(wm, AC97_EXTENDED_MID, val & 0x7fff);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2] |
+ WM97XX_PRP_DET_DIG);
+ wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
+ } else {
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2] &
+ ~WM97XX_PRP_DET_DIG);
+ val = wm97xx_reg_read(wm, AC97_EXTENDED_MID);
+ wm97xx_reg_write(wm, AC97_EXTENDED_MID, val | 0x8000);
+ }
+}
+
+static void wm9713_dig_restore(struct wm97xx *wm)
+{
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig_save[0]);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig_save[1]);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig_save[2]);
+}
+
+static void wm9713_aux_prepare(struct wm97xx *wm)
+{
+ memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, 0);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG2, 0);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, WM97XX_PRP_DET_DIG);
+}
+
+static inline int is_pden(struct wm97xx *wm)
+{
+ return wm->dig[2] & WM9713_PDEN;
+}
+
+/*
+ * Read a sample from the WM9713 adc in polling mode.
+ */
+static int wm9713_poll_sample(struct wm97xx *wm, int adcsel, int *sample)
+{
+ u16 dig1;
+ int timeout = 5 * delay;
+
+ if (!wm->pen_probably_down) {
+ u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (!(data & WM97XX_PEN_DOWN))
+ return RC_PENUP;
+ wm->pen_probably_down = 1;
+ }
+
+ /* set up digitiser */
+ if (adcsel & 0x8000)
+ adcsel = 1 << ((adcsel & 0x7fff) + 3);
+
+ dig1 = wm97xx_reg_read(wm, AC97_WM9713_DIG1);
+ dig1 &= ~WM9713_ADCSEL_MASK;
+
+ if (wm->mach_ops && wm->mach_ops->pre_sample)
+ wm->mach_ops->pre_sample(adcsel);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1 | adcsel | WM9713_POLL);
+
+ /* wait 3 AC97 time slots + delay for conversion */
+ poll_delay(delay);
+
+ /* wait for POLL to go low */
+ while ((wm97xx_reg_read(wm, AC97_WM9713_DIG1) & WM9713_POLL) &&
+ timeout) {
+ udelay(AC97_LINK_FRAME);
+ timeout--;
+ }
+
+ if (timeout <= 0) {
+ /* If PDEN is set, we can get a timeout when pen goes up */
+ if (is_pden(wm))
+ wm->pen_probably_down = 0;
+ else
+ dev_dbg(wm->dev, "adc sample timeout");
+ return RC_PENUP;
+ }
+
+ *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (wm->mach_ops && wm->mach_ops->post_sample)
+ wm->mach_ops->post_sample(adcsel);
+
+ /* check we have correct sample */
+ if ((*sample & WM97XX_ADCSRC_MASK) != ffs(adcsel >> 1) << 12) {
+ dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel,
+ *sample & WM97XX_ADCSRC_MASK);
+ return RC_PENUP;
+ }
+
+ if (!(*sample & WM97XX_PEN_DOWN)) {
+ wm->pen_probably_down = 0;
+ return RC_PENUP;
+ }
+
+ return RC_VALID;
+}
+
+/*
+ * Read a coordinate from the WM9713 adc in polling mode.
+ */
+static int wm9713_poll_coord(struct wm97xx *wm, struct wm97xx_data *data)
+{
+ u16 dig1;
+ int timeout = 5 * delay;
+
+ if (!wm->pen_probably_down) {
+ u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (!(data & WM97XX_PEN_DOWN))
+ return RC_PENUP;
+ wm->pen_probably_down = 1;
+ }
+
+ /* set up digitiser */
+ dig1 = wm97xx_reg_read(wm, AC97_WM9713_DIG1);
+ dig1 &= ~WM9713_ADCSEL_MASK;
+ if (pil)
+ dig1 |= WM97XX_ADCSEL_PRES;
+
+ if (wm->mach_ops && wm->mach_ops->pre_sample)
+ wm->mach_ops->pre_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1,
+ dig1 | WM9713_POLL | WM9713_COO);
+
+ /* wait 3 AC97 time slots + delay for conversion */
+ poll_delay(delay);
+ data->x = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ /* wait for POLL to go low */
+ while ((wm97xx_reg_read(wm, AC97_WM9713_DIG1) & WM9713_POLL)
+ && timeout) {
+ udelay(AC97_LINK_FRAME);
+ timeout--;
+ }
+
+ if (timeout <= 0) {
+ /* If PDEN is set, we can get a timeout when pen goes up */
+ if (is_pden(wm))
+ wm->pen_probably_down = 0;
+ else
+ dev_dbg(wm->dev, "adc sample timeout");
+ return RC_PENUP;
+ }
+
+ /* read back data */
+ data->y = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ if (pil)
+ data->p = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
+ else
+ data->p = DEFAULT_PRESSURE;
+
+ if (wm->mach_ops && wm->mach_ops->post_sample)
+ wm->mach_ops->post_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y);
+
+ /* check we have correct sample */
+ if (!(data->x & WM97XX_ADCSEL_X) || !(data->y & WM97XX_ADCSEL_Y))
+ goto err;
+ if (pil && !(data->p & WM97XX_ADCSEL_PRES))
+ goto err;
+
+ if (!(data->x & WM97XX_PEN_DOWN)) {
+ wm->pen_probably_down = 0;
+ return RC_PENUP;
+ }
+ return RC_VALID;
+err:
+ return RC_PENUP;
+}
+
+/*
+ * Sample the WM9713 touchscreen in polling mode
+ */
+static int wm9713_poll_touch(struct wm97xx *wm, struct wm97xx_data *data)
+{
+ int rc;
+
+ if (coord) {
+ rc = wm9713_poll_coord(wm, data);
+ if (rc != RC_VALID)
+ return rc;
+ } else {
+ rc = wm9713_poll_sample(wm, WM9713_ADCSEL_X, &data->x);
+ if (rc != RC_VALID)
+ return rc;
+ rc = wm9713_poll_sample(wm, WM9713_ADCSEL_Y, &data->y);
+ if (rc != RC_VALID)
+ return rc;
+ if (pil) {
+ rc = wm9713_poll_sample(wm, WM9713_ADCSEL_PRES,
+ &data->p);
+ if (rc != RC_VALID)
+ return rc;
+ } else
+ data->p = DEFAULT_PRESSURE;
+ }
+ return RC_VALID;
+}
+
+/*
+ * Enable WM9713 continuous mode, i.e. touch data is streamed across
+ * an AC97 slot
+ */
+static int wm9713_acc_enable(struct wm97xx *wm, int enable)
+{
+ u16 dig1, dig2, dig3;
+ int ret = 0;
+
+ dig1 = wm->dig[0];
+ dig2 = wm->dig[1];
+ dig3 = wm->dig[2];
+
+ if (enable) {
+ /* continous mode */
+ if (wm->mach_ops->acc_startup &&
+ (ret = wm->mach_ops->acc_startup(wm)) < 0)
+ return ret;
+
+ dig1 &= ~WM9713_ADCSEL_MASK;
+ dig1 |= WM9713_CTC | WM9713_COO | WM9713_ADCSEL_X |
+ WM9713_ADCSEL_Y;
+ if (pil)
+ dig1 |= WM9713_ADCSEL_PRES;
+ dig2 &= ~(WM97XX_DELAY_MASK | WM97XX_SLT_MASK |
+ WM97XX_CM_RATE_MASK);
+ dig2 |= WM97XX_SLEN | WM97XX_DELAY(delay) |
+ WM97XX_SLT(wm->acc_slot) | WM97XX_RATE(wm->acc_rate);
+ dig3 |= WM9713_PDEN;
+ } else {
+ dig1 &= ~(WM9713_CTC | WM9713_COO);
+ dig2 &= ~WM97XX_SLEN;
+ dig3 &= ~WM9713_PDEN;
+ if (wm->mach_ops->acc_shutdown)
+ wm->mach_ops->acc_shutdown(wm);
+ }
+
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG2, dig2);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, dig3);
+ return ret;
+}
+
+struct wm97xx_codec_drv wm9713_codec = {
+ .id = WM9713_ID2,
+ .name = "wm9713",
+ .poll_sample = wm9713_poll_sample,
+ .poll_touch = wm9713_poll_touch,
+ .acc_enable = wm9713_acc_enable,
+ .phy_init = wm9713_phy_init,
+ .dig_enable = wm9713_dig_enable,
+ .dig_restore = wm9713_dig_restore,
+ .aux_prepare = wm9713_aux_prepare,
+};
+EXPORT_SYMBOL_GPL(wm9713_codec);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <[email protected]>");
+MODULE_DESCRIPTION("WM9713 Touch Screen Driver");
+MODULE_LICENSE("GPL");
--
1.5.3.8

2008-01-18 16:28:53

by Mark Brown

[permalink] [raw]
Subject: [PATCH] Core driver for WM97xx touchscreens

This patch series adds support for the touchscreen controllers provided
by Wolfson Microelectronics WM97xx series chips in both polled and
streaming modes.

These drivers have been maintained out of tree since 2003. During that
time the driver the primary maintainer was Liam Girdwood and a number of
people have made contributions including Stanley Cai, Rodolfo Giometti,
Russell King, Marc Kleine-Budde, Ian Molton, Vincent Sanders, Andrew
Zabolotny, Graeme Gregory, Mike Arthur and myself. Apologies to anyone
I have omitted.

Signed-off-by: Liam Girdwood <[email protected]>
Signed-off-by: Graeme Gregory <[email protected]>
Signed-off-by: Mike Arthur <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Cc: Stanley Cai <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: Russell King <[email protected]>
Cc: Marc Kleine-Budde <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: Vincent Sanders <[email protected]>
Cc: Andrew Zabolotny <[email protected]>
---
drivers/input/touchscreen/wm97xx-core.c | 799 +++++++++++++++++++++++++++++++
include/linux/wm97xx.h | 311 ++++++++++++
2 files changed, 1110 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/wm97xx-core.c
create mode 100644 include/linux/wm97xx.h

diff --git a/drivers/input/touchscreen/wm97xx-core.c b/drivers/input/touchscreen/wm97xx-core.c
new file mode 100644
index 0000000..1f6d7a5
--- /dev/null
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -0,0 +1,799 @@
+/*
+ * wm97xx-core.c -- Touch screen driver core for Wolfson WM9705, WM9712
+ * and WM9713 AC97 Codecs.
+ *
+ * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ * [email protected] or [email protected]
+ * Parts Copyright : Ian Molton <[email protected]>
+ * Andrew Zabolotny <[email protected]>
+ * Russell King <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * Notes:
+ *
+ * Features:
+ * - supports WM9705, WM9712, WM9713
+ * - polling mode
+ * - continuous mode (arch-dependent)
+ * - adjustable rpu/dpp settings
+ * - adjustable pressure current
+ * - adjustable sample settle delay
+ * - 4 and 5 wire touchscreens (5 wire is WM9712 only)
+ * - pen down detection
+ * - battery monitor
+ * - sample AUX adcs
+ * - power management
+ * - codec GPIO
+ * - codec event notification
+ * Todo
+ * - Support for async sampling control for noisy LCDs.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+#include <linux/pm.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/workqueue.h>
+#include <linux/device.h>
+#include <linux/wm97xx.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#define TS_NAME "wm97xx"
+#define WM_CORE_VERSION "0.65"
+#define DEFAULT_PRESSURE 0xb0c0
+
+
+/*
+ * Touchscreen absolute values
+ *
+ * These parameters are used to help the input layer discard out of
+ * range readings and reduce jitter etc.
+ *
+ * o min, max:- indicate the min and max values your touch screen returns
+ * o fuzz:- use a higher number to reduce jitter
+ *
+ * The default values correspond to Mainstone II in QVGA mode
+ *
+ * Please read
+ * Documentation/input/input-programming.txt for more details.
+ */
+
+static int abs_x[3] = {350, 3900, 5};
+module_param_array(abs_x, int, NULL, 0);
+MODULE_PARM_DESC(abs_x, "Touchscreen absolute X min, max, fuzz");
+
+static int abs_y[3] = {320, 3750, 40};
+module_param_array(abs_y, int, NULL, 0);
+MODULE_PARM_DESC(abs_y, "Touchscreen absolute Y min, max, fuzz");
+
+static int abs_p[3] = {0, 150, 4};
+module_param_array(abs_p, int, NULL, 0);
+MODULE_PARM_DESC(abs_p, "Touchscreen absolute Pressure min, max, fuzz");
+
+/*
+ * wm97xx IO access, all IO locking done by AC97 layer
+ */
+int wm97xx_reg_read(struct wm97xx *wm, u16 reg)
+{
+ if (wm->ac97)
+ return wm->ac97->bus->ops->read(wm->ac97, reg);
+ else
+ return -1;
+}
+EXPORT_SYMBOL_GPL(wm97xx_reg_read);
+
+void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val)
+{
+ /* cache digitiser registers */
+ if (reg >= AC97_WM9713_DIG1 && reg <= AC97_WM9713_DIG3)
+ wm->dig[(reg - AC97_WM9713_DIG1) >> 1] = val;
+
+ /* cache gpio regs */
+ if (reg >= AC97_GPIO_CFG && reg <= AC97_MISC_AFE)
+ wm->gpio[(reg - AC97_GPIO_CFG) >> 1] = val;
+
+ /* wm9713 irq reg */
+ if (reg == 0x5a)
+ wm->misc = val;
+
+ if (wm->ac97)
+ wm->ac97->bus->ops->write(wm->ac97, reg, val);
+}
+EXPORT_SYMBOL_GPL(wm97xx_reg_write);
+
+/**
+ * wm97xx_read_aux_adc - Read the aux adc.
+ * @wm: wm97xx device.
+ * @adcsel: codec ADC to be read
+ *
+ * Reads the selected AUX ADC.
+ */
+
+int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel)
+{
+ int power_adc = 0, auxval;
+ u16 power = 0;
+
+ /* get codec */
+ mutex_lock(&wm->codec_mutex);
+
+ /* When the touchscreen is not in use, we may have to power up
+ * the AUX ADC before we can use sample the AUX inputs->
+ */
+ if (wm->id == WM9713_ID2 &&
+ (power = wm97xx_reg_read(wm, AC97_EXTENDED_MID)) & 0x8000) {
+ power_adc = 1;
+ wm97xx_reg_write(wm, AC97_EXTENDED_MID, power & 0x7fff);
+ }
+
+ /* Prepare the codec for AUX reading */
+ wm->codec->aux_prepare(wm);
+
+ /* Turn polling mode on to read AUX ADC */
+ wm->pen_probably_down = 1;
+ wm->codec->poll_sample(wm, adcsel, &auxval);
+
+ if (power_adc)
+ wm97xx_reg_write(wm, AC97_EXTENDED_MID, power | 0x8000);
+
+ wm->codec->dig_restore(wm);
+
+ wm->pen_probably_down = 0;
+
+ mutex_unlock(&wm->codec_mutex);
+ return auxval & 0xfff;
+}
+EXPORT_SYMBOL_GPL(wm97xx_read_aux_adc);
+
+/**
+ * wm97xx_get_gpio - Get the status of a codec GPIO.
+ * @wm: wm97xx device.
+ * @gpio: gpio
+ *
+ * Get the status of a codec GPIO pin
+ */
+
+enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio)
+{
+ u16 status;
+ enum wm97xx_gpio_status ret;
+
+ mutex_lock(&wm->codec_mutex);
+ status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+
+ if (status & gpio)
+ ret = WM97XX_GPIO_HIGH;
+ else
+ ret = WM97XX_GPIO_LOW;
+
+ mutex_unlock(&wm->codec_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(wm97xx_get_gpio);
+
+/**
+ * wm97xx_set_gpio - Set the status of a codec GPIO.
+ * @wm: wm97xx device.
+ * @gpio: gpio
+ *
+ *
+ * Set the status of a codec GPIO pin
+ */
+
+void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
+ enum wm97xx_gpio_status status)
+{
+ u16 reg;
+
+ mutex_lock(&wm->codec_mutex);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+
+ if (status & WM97XX_GPIO_HIGH)
+ reg |= gpio;
+ else
+ reg &= ~gpio;
+
+ if (wm->id == WM9712_ID2)
+ wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg << 1);
+ else
+ wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg);
+ mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_set_gpio);
+
+/*
+ * Codec GPIO pin configuration, this sets pin direction, polarity,
+ * stickyness and wake up.
+ */
+void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
+ enum wm97xx_gpio_pol pol, enum wm97xx_gpio_sticky sticky,
+ enum wm97xx_gpio_wake wake)
+{
+ u16 reg;
+
+ mutex_lock(&wm->codec_mutex);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+
+ if (pol == WM97XX_GPIO_POL_HIGH)
+ reg |= gpio;
+ else
+ reg &= ~gpio;
+
+ wm97xx_reg_write(wm, AC97_GPIO_POLARITY, reg);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
+
+ if (sticky == WM97XX_GPIO_STICKY)
+ reg |= gpio;
+ else
+ reg &= ~gpio;
+
+ wm97xx_reg_write(wm, AC97_GPIO_STICKY, reg);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
+
+ if (wake == WM97XX_GPIO_WAKE)
+ reg |= gpio;
+ else
+ reg &= ~gpio;
+
+ wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, reg);
+ reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
+
+ if (dir == WM97XX_GPIO_IN)
+ reg |= gpio;
+ else
+ reg &= ~gpio;
+
+ wm97xx_reg_write(wm, AC97_GPIO_CFG, reg);
+ mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
+
+/*
+ * Handle a pen down interrupt.
+ */
+static void wm97xx_pen_irq_worker(struct work_struct *work)
+{
+ struct wm97xx *wm = container_of(work, struct wm97xx, pen_event_work);
+
+ /* do we need to enable the touch panel reader */
+ if (wm->id == WM9705_ID2) {
+ if (wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD) &
+ WM97XX_PEN_DOWN)
+ wm->pen_is_down = 1;
+ else
+ wm->pen_is_down = 0;
+ } else {
+ u16 status, pol;
+ mutex_lock(&wm->codec_mutex);
+ status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+ pol = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+
+ if (WM97XX_GPIO_13 & pol & status) {
+ wm->pen_is_down = 1;
+ wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol &
+ ~WM97XX_GPIO_13);
+ } else {
+ wm->pen_is_down = 0;
+ wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol |
+ WM97XX_GPIO_13);
+ }
+
+ if (wm->id == WM9712_ID2)
+ wm97xx_reg_write(wm, AC97_GPIO_STATUS, (status &
+ ~WM97XX_GPIO_13) << 1);
+ else
+ wm97xx_reg_write(wm, AC97_GPIO_STATUS, status &
+ ~WM97XX_GPIO_13);
+ mutex_unlock(&wm->codec_mutex);
+ }
+
+ queue_delayed_work(wm->ts_workq, &wm->ts_reader, 0);
+
+ if (!wm->pen_is_down && wm->mach_ops && wm->mach_ops->acc_enabled)
+ wm->mach_ops->acc_pen_up(wm);
+ wm->mach_ops->irq_enable(wm, 1);
+}
+
+/*
+ * Codec PENDOWN irq handler
+ *
+ * We have to disable the codec interrupt in the handler because it can
+ * take upto 1ms to clear the interrupt source. The interrupt is then enabled
+ * again in the slow handler when the source has been cleared.
+ */
+static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
+{
+ struct wm97xx *wm = (struct wm97xx *) dev_id;
+ wm->mach_ops->irq_enable(wm, 0);
+ queue_work(wm->ts_workq, &wm->pen_event_work);
+ return IRQ_HANDLED;
+}
+
+/*
+ * initialise pen IRQ handler and workqueue
+ */
+static int wm97xx_init_pen_irq(struct wm97xx *wm)
+{
+ u16 reg;
+
+ /* If an interrupt is supplied an IRQ enable operation must also be
+ * provided. */
+ BUG_ON(!wm->mach_ops->irq_enable);
+
+ INIT_WORK(&wm->pen_event_work, wm97xx_pen_irq_worker);
+
+ if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
+ "wm97xx-pen", wm)) {
+ dev_err(wm->dev,
+ "Failed to register pen down interrupt, polling");
+ wm->pen_irq = 0;
+ return -EINVAL;
+ }
+
+ /* enable PEN down on wm9712/13 */
+ if (wm->id != WM9705_ID2) {
+ reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
+ wm97xx_reg_write(wm, AC97_MISC_AFE, reg & 0xfffb);
+ reg = wm97xx_reg_read(wm, 0x5a);
+ wm97xx_reg_write(wm, 0x5a, reg & ~0x0001);
+ }
+
+ return 0;
+}
+
+static int wm97xx_read_samples(struct wm97xx *wm)
+{
+ struct wm97xx_data data;
+ int rc;
+
+ mutex_lock(&wm->codec_mutex);
+
+ if (wm->mach_ops && wm->mach_ops->acc_enabled)
+ rc = wm->mach_ops->acc_pen_down(wm);
+ else
+ rc = wm->codec->poll_touch(wm, &data);
+
+ if (rc & RC_PENUP) {
+ if (wm->pen_is_down) {
+ wm->pen_is_down = 0;
+ dev_dbg(wm->dev, "pen up\n");
+ input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
+ input_sync(wm->input_dev);
+ } else if (!(rc & RC_AGAIN)) {
+ /* We need high frequency updates only while
+ * pen is down, the user never will be able to
+ * touch screen faster than a few times per
+ * second... On the other hand, when the user
+ * is actively working with the touchscreen we
+ * don't want to lose the quick response. So we
+ * will slowly increase sleep time after the
+ * pen is up and quicky restore it to ~one task
+ * switch when pen is down again.
+ */
+ if (wm->ts_reader_interval < HZ / 10)
+ wm->ts_reader_interval++;
+ }
+
+ } else if (rc & RC_VALID) {
+ dev_dbg(wm->dev,
+ "pen down: x=%x:%d, y=%x:%d, pressure=%x:%d\n",
+ data.x >> 12, data.x & 0xfff, data.y >> 12,
+ data.y & 0xfff, data.p >> 12, data.p & 0xfff);
+ input_report_abs(wm->input_dev, ABS_X, data.x & 0xfff);
+ input_report_abs(wm->input_dev, ABS_Y, data.y & 0xfff);
+ input_report_abs(wm->input_dev, ABS_PRESSURE, data.p & 0xfff);
+ input_sync(wm->input_dev);
+ wm->pen_is_down = 1;
+ wm->ts_reader_interval = wm->ts_reader_min_interval;
+ } else if (rc & RC_PENDOWN) {
+ dev_dbg(wm->dev, "pen down");
+ wm->pen_is_down = 1;
+ wm->ts_reader_interval = wm->ts_reader_min_interval;
+ }
+
+ mutex_unlock(&wm->codec_mutex);
+ return rc;
+}
+
+/*
+* The touchscreen sample reader.
+*/
+static void wm97xx_ts_reader(struct work_struct *work)
+{
+ int rc;
+ struct wm97xx *wm = container_of(work, struct wm97xx, ts_reader.work);
+
+ BUG_ON(!wm->codec);
+
+ do {
+ rc = wm97xx_read_samples(wm);
+ } while (rc & RC_AGAIN);
+
+ if (wm->pen_is_down || !wm->pen_irq)
+ queue_delayed_work(wm->ts_workq, &wm->ts_reader,
+ wm->ts_reader_interval);
+}
+
+/**
+ * wm97xx_ts_input_open - Open the touch screen input device.
+ * @idev: Input device to be opened.
+ *
+ * Called by the input sub system to open a wm97xx touchscreen device.
+ * Starts the touchscreen thread and touch digitiser.
+ */
+static int wm97xx_ts_input_open(struct input_dev *idev)
+{
+ struct wm97xx *wm = (struct wm97xx *)input_get_drvdata(idev);
+
+ mutex_lock(&wm->ts_mutex);
+ /* first time opened ? */
+ if (wm->ts_use_count++ == 0) {
+ wm->ts_workq = create_singlethread_workqueue("kwm97xx");
+ if (wm->ts_workq == NULL) {
+ dev_err(wm->dev,
+ "Failed to create workqueue\n");
+ mutex_unlock(&wm->ts_mutex);
+ return -EINVAL;
+ }
+
+ /* start digitiser */
+ if (wm->mach_ops && wm->mach_ops->acc_enabled)
+ wm->codec->acc_enable(wm, 1);
+ wm->codec->dig_enable(wm, 1);
+
+ INIT_DELAYED_WORK(&wm->ts_reader, wm97xx_ts_reader);
+
+ wm->ts_reader_min_interval = HZ >= 100 ? HZ / 100 : 1;
+ if (wm->ts_reader_min_interval < 1)
+ wm->ts_reader_min_interval = 1;
+ wm->ts_reader_interval = wm->ts_reader_min_interval;
+
+ wm->pen_is_down = 0;
+ if (wm->pen_irq)
+ wm97xx_init_pen_irq(wm);
+ else
+ dev_err(wm->dev, "No IRQ specified\n");
+
+ /* If we either don't have an interrupt for pen down
+ * events or failed to acquire it then we need to poll.
+ */
+ if (wm->pen_irq == 0)
+ queue_delayed_work(wm->ts_workq, &wm->ts_reader,
+ wm->ts_reader_interval);
+ }
+
+ mutex_unlock(&wm->ts_mutex);
+ return 0;
+}
+
+/**
+ * wm97xx_ts_input_close - Close the touch screen input device.
+ * @idev: Input device to be closed.
+ *
+ * Called by the input sub system to close a wm97xx touchscreen device.
+ * Kills the touchscreen thread and stops the touch digitiser.
+ */
+
+static void wm97xx_ts_input_close(struct input_dev *idev)
+{
+ struct wm97xx *wm = (struct wm97xx *)input_get_drvdata(idev);
+
+ mutex_lock(&wm->ts_mutex);
+ if (--wm->ts_use_count == 0) {
+ if (wm->pen_irq)
+ free_irq(wm->pen_irq, wm);
+
+ wm->pen_is_down = 0;
+
+ /* ts_reader rearms itself so we need to explicitly stop it
+ * before we destroy the workqueue.
+ */
+ cancel_delayed_work_sync(&wm->ts_reader);
+ destroy_workqueue(wm->ts_workq);
+
+ /* stop digitiser */
+ wm->codec->dig_enable(wm, 0);
+ if (wm->mach_ops && wm->mach_ops->acc_enabled)
+ wm->codec->acc_enable(wm, 0);
+ }
+ mutex_unlock(&wm->ts_mutex);
+}
+
+/*
+ * Bus interface to allow for client drivers codec access
+ * e.g. battery monitor
+ */
+static int wm97xx_bus_match(struct device *dev, struct device_driver *drv)
+{
+ return !(strcmp(dev->bus_id, drv->name));
+}
+
+/*
+ * The AC97 audio driver will do all the Codec suspend and resume
+ * tasks. This is just for anything machine specific or extra.
+ */
+static int wm97xx_bus_suspend(struct device *dev, pm_message_t state)
+{
+ int ret = 0;
+
+ if (dev->driver && dev->driver->suspend)
+ ret = dev->driver->suspend(dev, state);
+
+ return ret;
+}
+
+static int wm97xx_bus_resume(struct device *dev)
+{
+ int ret = 0;
+
+ if (dev->driver && dev->driver->resume)
+ ret = dev->driver->resume(dev);
+
+ return ret;
+}
+
+struct bus_type wm97xx_bus_type = {
+ .name = "wm97xx",
+ .match = wm97xx_bus_match,
+ .suspend = wm97xx_bus_suspend,
+ .resume = wm97xx_bus_resume,
+};
+EXPORT_SYMBOL_GPL(wm97xx_bus_type);
+
+static void wm97xx_release(struct device *dev)
+{
+ kfree(dev);
+}
+
+static int wm97xx_probe(struct device *dev)
+{
+ struct wm97xx *wm;
+ int ret = 0, id = 0;
+
+ wm = kzalloc(sizeof(struct wm97xx), GFP_KERNEL);
+ if (!wm)
+ return -ENOMEM;
+ mutex_init(&wm->codec_mutex);
+ mutex_init(&wm->ts_mutex);
+
+ wm->dev = dev;
+ dev->driver_data = wm;
+ wm->ac97 = to_ac97_t(dev);
+
+ /* check that we have a supported codec */
+ id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
+ if (id != WM97XX_ID1) {
+ dev_err(dev, "Device with vendor %04x is not a wm97xx\n", id);
+ kfree(wm);
+ return -ENODEV;
+ }
+
+ wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
+
+ dev_info(wm->dev, "detected a wm97%02x codec", wm->id & 0xff);
+
+ switch (wm->id & 0xff) {
+#ifdef CONFIG_TOUCHSCREEN_WM9705
+ case 0x05:
+ wm->codec = &wm9705_codec;
+ break;
+#endif
+#ifdef CONFIG_TOUCHSCREEN_WM9712
+ case 0x12:
+ wm->codec = &wm9712_codec;
+ break;
+#endif
+#ifdef CONFIG_TOUCHSCREEN_WM9713
+ case 0x13:
+ wm->codec = &wm9713_codec;
+ break;
+#endif
+ default:
+ dev_err(wm->dev, "Support for wm97%02x not compiled in.\n",
+ wm->id & 0xff);
+ kfree(wm);
+ return -ENODEV;
+ }
+
+ wm->input_dev = input_allocate_device();
+ if (wm->input_dev == NULL) {
+ kfree(wm);
+ return -ENOMEM;
+ }
+
+ /* set up touch configuration */
+ wm->input_dev->name = "wm97xx touchscreen";
+ wm->input_dev->open = wm97xx_ts_input_open;
+ wm->input_dev->close = wm97xx_ts_input_close;
+ set_bit(EV_ABS, wm->input_dev->evbit);
+ set_bit(ABS_X, wm->input_dev->absbit);
+ set_bit(ABS_Y, wm->input_dev->absbit);
+ set_bit(ABS_PRESSURE, wm->input_dev->absbit);
+ wm->input_dev->absmax[ABS_X] = abs_x[1];
+ wm->input_dev->absmax[ABS_Y] = abs_y[1];
+ wm->input_dev->absmax[ABS_PRESSURE] = abs_p[1];
+ wm->input_dev->absmin[ABS_X] = abs_x[0];
+ wm->input_dev->absmin[ABS_Y] = abs_y[0];
+ wm->input_dev->absmin[ABS_PRESSURE] = abs_p[0];
+ wm->input_dev->absfuzz[ABS_X] = abs_x[2];
+ wm->input_dev->absfuzz[ABS_Y] = abs_y[2];
+ wm->input_dev->absfuzz[ABS_PRESSURE] = abs_p[2];
+ input_set_drvdata(wm->input_dev, wm);
+ ret = input_register_device(wm->input_dev);
+ if (ret < 0) {
+ kfree(wm);
+ return -ENOMEM;
+ }
+
+ /* set up physical characteristics */
+ wm->codec->phy_init(wm);
+
+ /* load gpio cache */
+ wm->gpio[0] = wm97xx_reg_read(wm, AC97_GPIO_CFG);
+ wm->gpio[1] = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
+ wm->gpio[2] = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
+ wm->gpio[3] = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
+ wm->gpio[4] = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
+ wm->gpio[5] = wm97xx_reg_read(wm, AC97_MISC_AFE);
+
+ /* register our battery device */
+ wm->battery_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+ if (!wm->battery_dev) {
+ ret = -ENOMEM;
+ goto batt_err;
+ }
+ wm->battery_dev->bus = &wm97xx_bus_type;
+ strcpy(wm->battery_dev->bus_id, "wm97xx-battery");
+ wm->battery_dev->driver_data = wm;
+ wm->battery_dev->parent = dev;
+ wm->battery_dev->release = wm97xx_release;
+ ret = device_register(wm->battery_dev);
+ if (ret < 0)
+ goto batt_reg_err;
+
+ /* register our extended touch device (for machine specific
+ * extensions) */
+ wm->touch_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+ if (!wm->touch_dev) {
+ ret = -ENOMEM;
+ goto touch_err;
+ }
+ wm->touch_dev->bus = &wm97xx_bus_type;
+ strcpy(wm->touch_dev->bus_id, "wm97xx-touchscreen");
+ wm->touch_dev->driver_data = wm;
+ wm->touch_dev->parent = dev;
+ wm->touch_dev->release = wm97xx_release;
+ ret = device_register(wm->touch_dev);
+ if (ret < 0)
+ goto touch_reg_err;
+
+ return ret;
+
+ touch_reg_err:
+ kfree(wm->touch_dev);
+ touch_err:
+ device_unregister(wm->battery_dev);
+ batt_reg_err:
+ kfree(wm->battery_dev);
+ batt_err:
+ input_unregister_device(wm->input_dev);
+ kfree(wm);
+ return ret;
+}
+
+static int wm97xx_remove(struct device *dev)
+{
+ struct wm97xx *wm = dev_get_drvdata(dev);
+
+ device_unregister(wm->battery_dev);
+ device_unregister(wm->touch_dev);
+ input_unregister_device(wm->input_dev);
+
+ kfree(wm);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+int wm97xx_resume(struct device *dev)
+{
+ struct wm97xx *wm = dev_get_drvdata(dev);
+
+ /* restore digitiser and gpios */
+ if (wm->id == WM9713_ID2) {
+ wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig[0]);
+ wm97xx_reg_write(wm, 0x5a, wm->misc);
+ if (wm->ts_use_count) {
+ u16 reg;
+ reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) & 0x7fff;
+ wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
+ }
+ }
+
+ wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig[1]);
+ wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2]);
+
+ wm97xx_reg_write(wm, AC97_GPIO_CFG, wm->gpio[0]);
+ wm97xx_reg_write(wm, AC97_GPIO_POLARITY, wm->gpio[1]);
+ wm97xx_reg_write(wm, AC97_GPIO_STICKY, wm->gpio[2]);
+ wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, wm->gpio[3]);
+ wm97xx_reg_write(wm, AC97_GPIO_STATUS, wm->gpio[4]);
+ wm97xx_reg_write(wm, AC97_MISC_AFE, wm->gpio[5]);
+
+ return 0;
+}
+
+#else
+#define wm97xx_resume NULL
+#endif
+
+/*
+ * Machine specific operations
+ */
+int wm97xx_register_mach_ops(struct wm97xx *wm,
+ struct wm97xx_mach_ops *mach_ops)
+{
+ mutex_lock(&wm->codec_mutex);
+ if (wm->mach_ops) {
+ mutex_unlock(&wm->codec_mutex);
+ return -EINVAL;
+ }
+ wm->mach_ops = mach_ops;
+ mutex_unlock(&wm->codec_mutex);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(wm97xx_register_mach_ops);
+
+void wm97xx_unregister_mach_ops(struct wm97xx *wm)
+{
+ mutex_lock(&wm->codec_mutex);
+ wm->mach_ops = NULL;
+ mutex_unlock(&wm->codec_mutex);
+}
+EXPORT_SYMBOL_GPL(wm97xx_unregister_mach_ops);
+
+static struct device_driver wm97xx_driver = {
+ .name = "ac97",
+ .bus = &ac97_bus_type,
+ .owner = THIS_MODULE,
+ .probe = wm97xx_probe,
+ .remove = wm97xx_remove,
+ .resume = wm97xx_resume,
+};
+
+static int __init wm97xx_init(void)
+{
+ int ret;
+
+ ret = bus_register(&wm97xx_bus_type);
+ if (ret < 0)
+ return ret;
+ return driver_register(&wm97xx_driver);
+}
+
+static void __exit wm97xx_exit(void)
+{
+ driver_unregister(&wm97xx_driver);
+ bus_unregister(&wm97xx_bus_type);
+}
+
+module_init(wm97xx_init);
+module_exit(wm97xx_exit);
+
+/* Module information */
+MODULE_AUTHOR("Liam Girdwood <[email protected]>");
+MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/wm97xx.h b/include/linux/wm97xx.h
new file mode 100644
index 0000000..a19c56e
--- /dev/null
+++ b/include/linux/wm97xx.h
@@ -0,0 +1,311 @@
+
+/*
+ * Register bits and API for Wolfson WM97xx series of codecs
+ */
+
+#ifndef _LINUX_WM97XX_H
+#define _LINUX_WM97XX_H
+
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/ac97_codec.h>
+#include <sound/initval.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/input.h> /* Input device layer */
+
+/*
+ * WM97xx AC97 Touchscreen registers
+ */
+#define AC97_WM97XX_DIGITISER1 0x76
+#define AC97_WM97XX_DIGITISER2 0x78
+#define AC97_WM97XX_DIGITISER_RD 0x7a
+#define AC97_WM9713_DIG1 0x74
+#define AC97_WM9713_DIG2 AC97_WM97XX_DIGITISER1
+#define AC97_WM9713_DIG3 AC97_WM97XX_DIGITISER2
+
+/*
+ * WM97xx register bits
+ */
+#define WM97XX_POLL 0x8000 /* initiate a polling measurement */
+#define WM97XX_ADCSEL_X 0x1000 /* x coord measurement */
+#define WM97XX_ADCSEL_Y 0x2000 /* y coord measurement */
+#define WM97XX_ADCSEL_PRES 0x3000 /* pressure measurement */
+#define WM97XX_ADCSEL_MASK 0x7000
+#define WM97XX_COO 0x0800 /* enable coordinate mode */
+#define WM97XX_CTC 0x0400 /* enable continuous mode */
+#define WM97XX_CM_RATE_93 0x0000 /* 93.75Hz continuous rate */
+#define WM97XX_CM_RATE_187 0x0100 /* 187.5Hz continuous rate */
+#define WM97XX_CM_RATE_375 0x0200 /* 375Hz continuous rate */
+#define WM97XX_CM_RATE_750 0x0300 /* 750Hz continuous rate */
+#define WM97XX_CM_RATE_8K 0x00f0 /* 8kHz continuous rate */
+#define WM97XX_CM_RATE_12K 0x01f0 /* 12kHz continuous rate */
+#define WM97XX_CM_RATE_24K 0x02f0 /* 24kHz continuous rate */
+#define WM97XX_CM_RATE_48K 0x03f0 /* 48kHz continuous rate */
+#define WM97XX_CM_RATE_MASK 0x03f0
+#define WM97XX_RATE(i) (((i & 3) << 8) | ((i & 4) ? 0xf0 : 0))
+#define WM97XX_DELAY(i) ((i << 4) & 0x00f0) /* sample delay times */
+#define WM97XX_DELAY_MASK 0x00f0
+#define WM97XX_SLEN 0x0008 /* slot read back enable */
+#define WM97XX_SLT(i) ((i - 5) & 0x7) /* panel slot (5-11) */
+#define WM97XX_SLT_MASK 0x0007
+#define WM97XX_PRP_DETW 0x4000 /* detect on, digitise off, wake */
+#define WM97XX_PRP_DET 0x8000 /* detect on, digitise off, no wake */
+#define WM97XX_PRP_DET_DIG 0xc000 /* setect on, digitise on */
+#define WM97XX_RPR 0x2000 /* wake up on pen down */
+#define WM97XX_PEN_DOWN 0x8000 /* pen is down */
+#define WM97XX_ADCSRC_MASK 0x7000 /* ADC source mask */
+
+#define WM97XX_AUX_ID1 0x8001
+#define WM97XX_AUX_ID2 0x8002
+#define WM97XX_AUX_ID3 0x8003
+#define WM97XX_AUX_ID4 0x8004
+
+
+/* WM9712 Bits */
+#define WM9712_45W 0x1000 /* set for 5-wire touchscreen */
+#define WM9712_PDEN 0x0800 /* measure only when pen down */
+#define WM9712_WAIT 0x0200 /* wait until adc is read before next sample */
+#define WM9712_PIL 0x0100 /* current used for pressure measurement. set 400uA else 200uA */
+#define WM9712_MASK_HI 0x0040 /* hi on mask pin (47) stops conversions */
+#define WM9712_MASK_EDGE 0x0080 /* rising/falling edge on pin delays sample */
+#define WM9712_MASK_SYNC 0x00c0 /* rising/falling edge on mask initiates sample */
+#define WM9712_RPU(i) (i&0x3f) /* internal pull up on pen detect (64k / rpu) */
+#define WM9712_PD(i) (0x1 << i) /* power management */
+
+/* WM9712 Registers */
+#define AC97_WM9712_POWER 0x24
+#define AC97_WM9712_REV 0x58
+
+/* WM9705 Bits */
+#define WM9705_PDEN 0x1000 /* measure only when pen is down */
+#define WM9705_PINV 0x0800 /* inverts sense of pen down output */
+#define WM9705_BSEN 0x0400 /* BUSY flag enable, pin47 is 1 when busy */
+#define WM9705_BINV 0x0200 /* invert BUSY (pin47) output */
+#define WM9705_WAIT 0x0100 /* wait until adc is read before next sample */
+#define WM9705_PIL 0x0080 /* current used for pressure measurement. set 400uA else 200uA */
+#define WM9705_PHIZ 0x0040 /* set PHONE and PCBEEP inputs to high impedance */
+#define WM9705_MASK_HI 0x0010 /* hi on mask stops conversions */
+#define WM9705_MASK_EDGE 0x0020 /* rising/falling edge on pin delays sample */
+#define WM9705_MASK_SYNC 0x0030 /* rising/falling edge on mask initiates sample */
+#define WM9705_PDD(i) (i & 0x000f) /* pen detect comparator threshold */
+
+
+/* WM9713 Bits */
+#define WM9713_PDPOL 0x0400 /* Pen down polarity */
+#define WM9713_POLL 0x0200 /* initiate a polling measurement */
+#define WM9713_CTC 0x0100 /* enable continuous mode */
+#define WM9713_ADCSEL_X 0x0002 /* X measurement */
+#define WM9713_ADCSEL_Y 0x0004 /* Y measurement */
+#define WM9713_ADCSEL_PRES 0x0008 /* Pressure measurement */
+#define WM9713_COO 0x0001 /* enable coordinate mode */
+#define WM9713_PDEN 0x0800 /* measure only when pen down */
+#define WM9713_ADCSEL_MASK 0x00fe /* ADC selection mask */
+#define WM9713_WAIT 0x0200 /* coordinate wait */
+
+/* AUX ADC ID's */
+#define TS_COMP1 0x0
+#define TS_COMP2 0x1
+#define TS_BMON 0x2
+#define TS_WIPER 0x3
+
+/* ID numbers */
+#define WM97XX_ID1 0x574d
+#define WM9712_ID2 0x4c12
+#define WM9705_ID2 0x4c05
+#define WM9713_ID2 0x4c13
+
+/* Codec GPIO's */
+#define WM97XX_MAX_GPIO 16
+#define WM97XX_GPIO_1 (1 << 1)
+#define WM97XX_GPIO_2 (1 << 2)
+#define WM97XX_GPIO_3 (1 << 3)
+#define WM97XX_GPIO_4 (1 << 4)
+#define WM97XX_GPIO_5 (1 << 5)
+#define WM97XX_GPIO_6 (1 << 6)
+#define WM97XX_GPIO_7 (1 << 7)
+#define WM97XX_GPIO_8 (1 << 8)
+#define WM97XX_GPIO_9 (1 << 9)
+#define WM97XX_GPIO_10 (1 << 10)
+#define WM97XX_GPIO_11 (1 << 11)
+#define WM97XX_GPIO_12 (1 << 12)
+#define WM97XX_GPIO_13 (1 << 13)
+#define WM97XX_GPIO_14 (1 << 14)
+#define WM97XX_GPIO_15 (1 << 15)
+
+
+#define AC97_LINK_FRAME 21 /* time in uS for AC97 link frame */
+
+
+/*---------------- Return codes from sample reading functions ---------------*/
+
+/* More data is available; call the sample gathering function again */
+#define RC_AGAIN 0x00000001
+/* The returned sample is valid */
+#define RC_VALID 0x00000002
+/* The pen is up (the first RC_VALID without RC_PENUP means pen is down) */
+#define RC_PENUP 0x00000004
+/* The pen is down (RC_VALID implies RC_PENDOWN, but sometimes it is helpful
+ to tell the handler that the pen is down but we don't know yet his coords,
+ so the handler should not sleep or wait for pendown irq) */
+#define RC_PENDOWN 0x00000008
+
+/*
+ * The wm97xx driver provides a private API for writing platform-specific
+ * drivers.
+ */
+
+/* The structure used to return arch specific sampled data into */
+struct wm97xx_data {
+ int x;
+ int y;
+ int p;
+};
+
+/*
+ * Codec GPIO status
+ */
+enum wm97xx_gpio_status {
+ WM97XX_GPIO_HIGH,
+ WM97XX_GPIO_LOW
+};
+
+/*
+ * Codec GPIO direction
+ */
+enum wm97xx_gpio_dir {
+ WM97XX_GPIO_IN,
+ WM97XX_GPIO_OUT
+};
+
+/*
+ * Codec GPIO polarity
+ */
+enum wm97xx_gpio_pol {
+ WM97XX_GPIO_POL_HIGH,
+ WM97XX_GPIO_POL_LOW
+};
+
+/*
+ * Codec GPIO sticky
+ */
+enum wm97xx_gpio_sticky {
+ WM97XX_GPIO_STICKY,
+ WM97XX_GPIO_NOTSTICKY
+};
+
+/*
+ * Codec GPIO wake
+ */
+enum wm97xx_gpio_wake {
+ WM97XX_GPIO_WAKE,
+ WM97XX_GPIO_NOWAKE
+};
+
+/*
+ * Digitiser ioctl commands
+ */
+#define WM97XX_DIG_START 0x1
+#define WM97XX_DIG_STOP 0x2
+#define WM97XX_PHY_INIT 0x3
+#define WM97XX_AUX_PREPARE 0x4
+#define WM97XX_DIG_RESTORE 0x5
+
+struct wm97xx;
+
+extern struct wm97xx_codec_drv wm9705_codec;
+extern struct wm97xx_codec_drv wm9712_codec;
+extern struct wm97xx_codec_drv wm9713_codec;
+
+/*
+ * Codec driver interface - allows mapping to WM9705/12/13 and newer codecs
+ */
+struct wm97xx_codec_drv {
+ u16 id;
+ char *name;
+
+ /* read 1 sample */
+ int (*poll_sample) (struct wm97xx *, int adcsel, int *sample);
+
+ /* read X,Y,[P] in poll */
+ int (*poll_touch) (struct wm97xx *, struct wm97xx_data *);
+
+ int (*acc_enable) (struct wm97xx *, int enable);
+ void (*phy_init) (struct wm97xx *);
+ void (*dig_enable) (struct wm97xx *, int enable);
+ void (*dig_restore) (struct wm97xx *);
+ void (*aux_prepare) (struct wm97xx *);
+};
+
+
+/* Machine specific and accelerated touch operations */
+struct wm97xx_mach_ops {
+
+ /* accelerated touch readback - coords are transmited on AC97 link */
+ int acc_enabled;
+ void (*acc_pen_up) (struct wm97xx *);
+ int (*acc_pen_down) (struct wm97xx *);
+ int (*acc_startup) (struct wm97xx *);
+ void (*acc_shutdown) (struct wm97xx *);
+
+ /* interrupt mask control - required for accelerated operation */
+ void (*irq_enable) (struct wm97xx *, int enable);
+
+ /* pre and post sample - can be used to minimise any analog noise */
+ void (*pre_sample) (int); /* function to run before sampling */
+ void (*post_sample) (int); /* function to run after sampling */
+};
+
+struct wm97xx {
+ u16 dig[3], id, gpio[6], misc; /* Cached codec registers */
+ u16 dig_save[3]; /* saved during aux reading */
+ struct wm97xx_codec_drv *codec; /* attached codec driver*/
+ struct input_dev *input_dev; /* touchscreen input device */
+ struct snd_ac97 *ac97; /* ALSA codec access */
+ struct device *dev; /* ALSA device */
+ struct device *battery_dev;
+ struct device *touch_dev;
+ struct wm97xx_mach_ops *mach_ops;
+ struct mutex codec_mutex;
+ struct mutex ts_mutex;
+ struct delayed_work ts_reader; /* Used to poll touchscreen */
+ unsigned long ts_reader_interval; /* Current interval for timer */
+ unsigned long ts_reader_min_interval; /* Minimum interval */
+ unsigned int pen_irq; /* Pen IRQ number in use */
+ struct workqueue_struct *ts_workq;
+ struct work_struct pen_event_work;
+ u16 acc_slot; /* AC97 slot used for acc touch data */
+ u16 acc_rate; /* acc touch data rate */
+ unsigned int ts_use_count;
+ unsigned pen_is_down:1; /* Pen is down */
+ unsigned aux_waiting:1; /* aux measurement waiting */
+ unsigned pen_probably_down:1; /* used in polling mode */
+};
+
+/*
+ * Codec GPIO access (not supported on WM9705)
+ * This can be used to set/get codec GPIO and Virtual GPIO status.
+ */
+enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio);
+void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
+ enum wm97xx_gpio_status status);
+void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio,
+ enum wm97xx_gpio_dir dir,
+ enum wm97xx_gpio_pol pol,
+ enum wm97xx_gpio_sticky sticky,
+ enum wm97xx_gpio_wake wake);
+
+/* codec AC97 IO access */
+int wm97xx_reg_read(struct wm97xx *wm, u16 reg);
+void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val);
+
+/* aux adc readback */
+int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel);
+
+/* machine ops */
+int wm97xx_register_mach_ops(struct wm97xx *, struct wm97xx_mach_ops *);
+void wm97xx_unregister_mach_ops(struct wm97xx *);
+
+extern struct bus_type wm97xx_bus_type;
+#endif
--
1.5.3.8

2008-01-18 17:23:55

by Dmitry Torokhov

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

Hi Mark,

On Fri, Jan 18, 2008 at 04:27:06PM +0000, Mark Brown wrote:
> This patch series adds support for the touchscreen controllers provided
> by Wolfson Microelectronics WM97xx series chips in both polled and
> streaming modes.
>

Thank you for the patches. Some comments below.

> +static int wm97xx_ts_input_open(struct input_dev *idev)
> +{
> + struct wm97xx *wm = (struct wm97xx *)input_get_drvdata(idev);

No need to cast.

> +
> + mutex_lock(&wm->ts_mutex);
> + /* first time opened ? */
> + if (wm->ts_use_count++ == 0) {

You do not need to implement a counter here. Input core makes sure
that open and close are only called for the fist and last user
respectivly. ts_mutex can go away as well.

> + /* set up touch configuration */
> + wm->input_dev->name = "wm97xx touchscreen";
> + wm->input_dev->open = wm97xx_ts_input_open;
> + wm->input_dev->close = wm97xx_ts_input_close;
> + set_bit(EV_ABS, wm->input_dev->evbit);
> + set_bit(ABS_X, wm->input_dev->absbit);
> + set_bit(ABS_Y, wm->input_dev->absbit);
> + set_bit(ABS_PRESSURE, wm->input_dev->absbit);
> + wm->input_dev->absmax[ABS_X] = abs_x[1];
> + wm->input_dev->absmax[ABS_Y] = abs_y[1];
> + wm->input_dev->absmax[ABS_PRESSURE] = abs_p[1];
> + wm->input_dev->absmin[ABS_X] = abs_x[0];
> + wm->input_dev->absmin[ABS_Y] = abs_y[0];
> + wm->input_dev->absmin[ABS_PRESSURE] = abs_p[0];
> + wm->input_dev->absfuzz[ABS_X] = abs_x[2];
> + wm->input_dev->absfuzz[ABS_Y] = abs_y[2];
> + wm->input_dev->absfuzz[ABS_PRESSURE] = abs_p[2];

input_set-abs_params(wm->input_dev, ABS_X, ...);
input_set-abs_params(wm->input_dev, ABS_Y, ...);
input_set-abs_params(wm->input_dev, ABS_X, ...);

I'd also recoomend using a temp for wm->input_dev, shoudl save a couple
of bytes.

> + input_set_drvdata(wm->input_dev, wm);

Also wm->input_dev->dev.parent = &dev; to put it in the proper place
in sysfs hierarchy.

> + ret = input_register_device(wm->input_dev);
> + if (ret < 0) {

Add input_free_device(); here.

> + kfree(wm);
> + return -ENOMEM;
> + }

I will need some more time to review and understand the need for the new bus
in the driver.

Thanks.

--
Dmitry

2008-01-18 18:12:25

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

Hi,

Dmitry Torokhov wrote:

> I will need some more time to review and understand the need for the new
> bus in the driver.

Most likely this can be converted to platform_bus. Maybe this can also get
help from soon-to-be posted MFD (multi function devices) helpers.

--
With best wishes
Dmitry

2008-01-18 21:57:25

by Ben Dooks

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

On Fri, Jan 18, 2008 at 06:11:45PM +0000, Dmitry Baryshkov wrote:
> Hi,
>
> Dmitry Torokhov wrote:
>
> > I will need some more time to review and understand the need for the new
> > bus in the driver.
>
> Most likely this can be converted to platform_bus. Maybe this can also get
> help from soon-to-be posted MFD (multi function devices) helpers.

Is there any current discussion of these in public? I'm interested
mainly due to my involvement in the SM501 core and FB driver. Can
I also request to be Cc'd when these are posted?

--
Ben ([email protected], http://www.fluff.org/)

'a smiley only costs 4 bytes'

2008-01-19 17:41:18

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

On Fri, Jan 18, 2008 at 06:11:45PM +0000, Dmitry Baryshkov wrote:
> Dmitry Torokhov wrote:

> > I will need some more time to review and understand the need for the new
> > bus in the driver.

> Most likely this can be converted to platform_bus. Maybe this can also get

Could you expand on how you see that being implemented, please? It
doesn't feel entirely comfortable to me - providing a bus for the chip
seems more direct and the platform bus not what I'd think of using for
something hanging off another bus - but I think I'm just not visualising
what you're thinking of properly.

> help from soon-to-be posted MFD (multi function devices) helpers.

The multi-function device support does feel like it could be a good fit.
I'd seen it discussed sometime last year but don't recall seeing
anything for quite a while. Like Ben said, any pointers to current work
would be appreciated.

It's probably worth mentioning that in addition to what is in the
current patch series these chips all also provide an audio codec which
requires a reasonably substantial driver for full support.

2008-01-19 19:48:47

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

Hi,

2008/1/19, Mark Brown <[email protected]>:
> On Fri, Jan 18, 2008 at 06:11:45PM +0000, Dmitry Baryshkov wrote:
> > Dmitry Torokhov wrote:
>
> > > I will need some more time to review and understand the need for the new
> > > bus in the driver.
>
> > Most likely this can be converted to platform_bus. Maybe this can also get
>
> Could you expand on how you see that being implemented, please? It
> doesn't feel entirely comfortable to me - providing a bus for the chip
> seems more direct and the platform bus not what I'd think of using for
> something hanging off another bus - but I think I'm just not visualising
> what you're thinking of properly.

Well... It's a common suggestion not to duplicate code. The wm97xx bus
looks mostly like platform. The only difference is the name. To help
visualisation, devices can have parents. Just set (in pseudocode)
wm97xx-touchscreen->parent to wm97xx, do the same for wm97xx-battery
and so on. Thus all devices would be on the platform device but with
proper parent <-> child notation.

> > help from soon-to-be posted MFD (multi function devices) helpers.
>
> The multi-function device support does feel like it could be a good fit.
> I'd seen it discussed sometime last year but don't recall seeing
> anything for quite a while. Like Ben said, any pointers to current work
> would be appreciated.

You can find the current work at
git://git.mnementh.co.uk/linux-2.6-im.git#tmio_dev_try3. Look for
"Core MFD support" changeset.

>
> It's probably worth mentioning that in addition to what is in the
> current patch series these chips all also provide an audio codec which
> requires a reasonably substantial driver for full support.
>

This would only touch child devices organisation.

--
With best wishes
Dmitry

2008-01-19 19:53:23

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

Ben Dooks wrote:

> On Fri, Jan 18, 2008 at 06:11:45PM +0000, Dmitry Baryshkov wrote:
>> Hi,
>>
>> Dmitry Torokhov wrote:
>>
>> > I will need some more time to review and understand the need for the
>> > new bus in the driver.
>>
>> Most likely this can be converted to platform_bus. Maybe this can also
>> get help from soon-to-be posted MFD (multi function devices) helpers.
>
> Is there any current discussion of these in public? I'm interested
> mainly due to my involvement in the SM501 core and FB driver. Can I also
> request to be Cc'd when these are posted?


You can find the current work at
git://git.mnementh.co.uk/linux-2.6-im.git#tmio_dev_try3. Look for "Core MFD support" changeset.
For CC concact Ian <[email protected]>.

>
> --
> Ben ([email protected], http://www.fluff.org/)
>
> 'a smiley only costs 4 bytes'





--
With best wishes
Dmitry

2008-01-19 21:55:24

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

On Sat, Jan 19, 2008 at 10:48:32PM +0300, Dmitry wrote:

> Well... It's a common suggestion not to duplicate code. The wm97xx bus
> looks mostly like platform. The only difference is the name. To help
> visualisation, devices can have parents. Just set (in pseudocode)
> wm97xx-touchscreen->parent to wm97xx, do the same for wm97xx-battery
> and so on. Thus all devices would be on the platform device but with
> proper parent <-> child notation.

That's exactly what I had understood you to mean. I guess it's just
that using the platform bus for this purpose feels like an abstraction
violation to me due to having platform devices parented off a device on
another bus. Obviously it's just my model of a platform device that's
wrong here. I will change the driver to use the platform bus for my
next submission.

> git://git.mnementh.co.uk/linux-2.6-im.git#tmio_dev_try3. Look for

Thanks, I'll take a look.

> 2008/1/19, Mark Brown <[email protected]>:

> > current patch series these chips all also provide an audio codec which
> > requires a reasonably substantial driver for full support.

> This would only touch child devices organisation.

Indeed - I mention it mostly for additional motivation.

2008-01-19 22:18:53

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH] Core driver for WM97xx touchscreens

Hi,

2008/1/20, Mark Brown <[email protected]>:
> On Sat, Jan 19, 2008 at 10:48:32PM +0300, Dmitry wrote:
>
> > Well... It's a common suggestion not to duplicate code. The wm97xx bus
> > looks mostly like platform. The only difference is the name. To help
> > visualisation, devices can have parents. Just set (in pseudocode)
> > wm97xx-touchscreen->parent to wm97xx, do the same for wm97xx-battery
> > and so on. Thus all devices would be on the platform device but with
> > proper parent <-> child notation.
>
> That's exactly what I had understood you to mean. I guess it's just
> that using the platform bus for this purpose feels like an abstraction
> violation to me due to having platform devices parented off a device on
> another bus. Obviously it's just my model of a platform device that's
> wrong here. I will change the driver to use the platform bus for my
> next submission.

Hmm. I forgot about rooting this onto ac97 bus. But I would still suggest
using platform bus just for the sake of code clarity and simplicity.

>
> > git://git.mnementh.co.uk/linux-2.6-im.git#tmio_dev_try3. Look for
>
> Thanks, I'll take a look.
>
> > 2008/1/19, Mark Brown <[email protected]>:
>
> > > current patch series these chips all also provide an audio codec which
> > > requires a reasonably substantial driver for full support.
>
> > This would only touch child devices organisation.
>
> Indeed - I mention it mostly for additional motivation.
>


--
With best wishes
Dmitry