On TI DA850/OMAP-L138 EVM, HD44780 (24x2) LCD panel is
being used, interfaced through the SoC specific LCD
interface[1].
Driver from drivers/staging/panel/panel.c works for this
LCD panel but that driver expects the LCD panel to be
interfaced through a parallel port.
This patch implements a dummy parallel port driver which
interfaces to the panel driver in staging area through the
LCD interface available on SoC.
Signed-off-by: Sudhakar Rajashekhara <[email protected]>
---
drivers/parport/Kconfig | 8 +
drivers/parport/Makefile | 3 +-
drivers/parport/parport_da8xx.c | 324 +++++++++++++++++++++++++++++++++
include/linux/parport_da8xx.h | 28 +++
4 files changed, 362 insertions(+), 1 deletions(-)
create mode 100644 drivers/parport/parport_da8xx.c
create mode 100644 include/linux/parport_da8xx.h
diff --git a/drivers/parport/Kconfig b/drivers/parport/Kconfig
index 855f389..5709b88 100644
--- a/drivers/parport/Kconfig
+++ b/drivers/parport/Kconfig
@@ -154,6 +154,14 @@ config PARPORT_1284
transfer modes. Also say Y if you want device ID information to
appear in /proc/sys/dev/parport/*/autoprobe*. It is safe to say N.
+config PARPORT_DA8XX
+ tristate "DA8XX Dummy Parallel Port"
+ depends on ARCH_DAVINCI_DA8XX && !(FB_DA8XX = y) && !(FB_DA8XX = m)
+ select PARPORT_NOT_PC
+ help
+ Say Y here if you need support for the DA8XX/OMAP-L1XX character
+ LCD which is using the staging panel driver.
+
config PARPORT_NOT_PC
bool
diff --git a/drivers/parport/Makefile b/drivers/parport/Makefile
index 696b8d4..ad7dfd0 100644
--- a/drivers/parport/Makefile
+++ b/drivers/parport/Makefile
@@ -18,4 +18,5 @@ obj-$(CONFIG_PARPORT_ATARI) += parport_atari.o
obj-$(CONFIG_PARPORT_SUNBPP) += parport_sunbpp.o
obj-$(CONFIG_PARPORT_GSC) += parport_gsc.o
obj-$(CONFIG_PARPORT_AX88796) += parport_ax88796.o
-obj-$(CONFIG_PARPORT_IP32) += parport_ip32.o
\ No newline at end of file
+obj-$(CONFIG_PARPORT_IP32) += parport_ip32.o
+obj-$(CONFIG_PARPORT_DA8XX) += parport_da8xx.o
diff --git a/drivers/parport/parport_da8xx.c b/drivers/parport/parport_da8xx.c
new file mode 100644
index 0000000..117123f
--- /dev/null
+++ b/drivers/parport/parport_da8xx.c
@@ -0,0 +1,324 @@
+/* linux/drivers/parport/parport_da8xx.c
+ *
+ * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * 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 version 2.
+ *
+ * This program is distributed .as is. WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/parport.h>
+#include <linux/parport_da8xx.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+#include <asm/irq.h>
+
+/* LCDC register offsets */
+#define LCDC_LCD_CTRL 0x04
+#define LCDC_LIDD_CTRL 0x0c
+#define LCDC_LIDD_CS0_CONF 0x10
+#define LCDC_LIDD_CS0_ADDR 0x14
+#define LCDC_LIDD_CS0_DATA 0x18
+#define LCDC_LIDD_CS1_CONF 0x1c
+#define LCDC_LIDD_CS1_ADDR 0x20
+#define LCDC_LIDD_CS1_DATA 0x24
+
+#define LCD_CTRL_RASTER_MODE BIT(0)
+#define LIDD_CONF_W_SU BIT(27)
+#define LIDD_CONF_W_STROBE (4 << 21)
+#define LIDD_CONF_W_HOLD BIT(17)
+#define LIDD_CONF_R_SU BIT(12)
+#define LIDD_CONF_R_STROBE (4 << 6)
+#define LIDD_CONF_R_HOLD BIT(2)
+#define LIDD_CTRL_MODE_SEL_MASK 0x7
+#define LIDD_CTRL_MODE_HITACHI 0x4
+
+struct da8xx_drvdata {
+ struct parport *parport;
+
+ struct device *dev;
+ struct resource *io;
+ struct clk *clk;
+
+ unsigned char irq_enabled;
+ unsigned char version;
+
+ void __iomem *base;
+ void __iomem *spp_data;
+ void __iomem *spp_cpr;
+};
+
+static inline struct da8xx_drvdata *pp_to_drv(struct parport *p)
+{
+ return p->private_data;
+}
+
+static void
+parport_da8xx_init_state(struct pardevice *d, struct parport_state *s)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(d->port);
+
+ memset(s, 0, sizeof(struct parport_state));
+
+ dev_dbg(dd->dev, "init_state: %p: state=%p\n", d, s);
+}
+
+static void
+parport_da8xx_save_state(struct parport *p, struct parport_state *s)
+{
+ /* do nothing */
+}
+
+static void
+parport_da8xx_restore_state(struct parport *p, struct parport_state *s)
+{
+ /* do nothing */
+}
+
+static unsigned char
+parport_da8xx_read_data(struct parport *p)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+
+ return readl(dd->spp_data);
+}
+
+static void
+parport_da8xx_write_data(struct parport *p, unsigned char data)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+
+ writel(data, dd->spp_data);
+}
+
+static unsigned char
+parport_da8xx_read_control(struct parport *p)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+
+ return readl(dd->spp_cpr);
+}
+
+static void
+parport_da8xx_write_control(struct parport *p, unsigned char control)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+
+ writel(control, dd->spp_cpr);
+}
+
+static void da8xx_init_clcd(struct parport *p)
+{
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+ unsigned int regval;
+
+ regval = readl(dd->base + LCDC_LCD_CTRL);
+ regval &= ~LCD_CTRL_RASTER_MODE;
+ writel(regval, dd->base + LCDC_LCD_CTRL);
+
+ regval = readl(dd->base + LCDC_LCD_CTRL);
+ regval &= ~0xFF00;
+ writel(regval, dd->base + LCDC_LCD_CTRL);
+
+ regval = readl(dd->base + LCDC_LCD_CTRL);
+ regval |= 0x7F00;
+ writel(regval, dd->base + LCDC_LCD_CTRL);
+
+ regval = readl(dd->base + LCDC_LIDD_CTRL);
+ regval &= ~LIDD_CTRL_MODE_SEL_MASK;
+ writel(regval, dd->base + LCDC_LIDD_CTRL);
+
+ regval = readl(dd->base + LCDC_LIDD_CTRL);
+ regval |= LIDD_CTRL_MODE_HITACHI;
+ writel(regval, dd->base + LCDC_LIDD_CTRL);
+
+ regval = LIDD_CONF_W_SU | LIDD_CONF_W_STROBE | LIDD_CONF_W_HOLD |
+ LIDD_CONF_R_SU | LIDD_CONF_R_STROBE | LIDD_CONF_R_HOLD;
+
+ if (dd->version == CONFIG_SPACE_0)
+ writel(regval, dd->base + LCDC_LIDD_CS0_CONF);
+ else
+ writel(regval, dd->base + LCDC_LIDD_CS1_CONF);
+}
+
+static struct parport_operations parport_da8xx_ops = {
+ .init_state = parport_da8xx_init_state,
+ .save_state = parport_da8xx_save_state,
+ .restore_state = parport_da8xx_restore_state,
+
+ .write_data = parport_da8xx_write_data,
+ .read_data = parport_da8xx_read_data,
+
+ .write_control = parport_da8xx_write_control,
+ .read_control = parport_da8xx_read_control,
+
+ .owner = THIS_MODULE,
+};
+
+static int parport_da8xx_probe(struct platform_device *pdev)
+{
+ struct da8xx_clcd_platform_data *pdata = pdev->dev.platform_data;
+ struct device *_dev = &pdev->dev;
+ struct da8xx_drvdata *dd;
+ struct parport *pp = NULL;
+ struct resource *res;
+ unsigned long size;
+ int irq;
+ int ret;
+
+ dd = kzalloc(sizeof(struct da8xx_drvdata), GFP_KERNEL);
+ if (dd == NULL) {
+ dev_err(_dev, "no memory for private data\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(_dev, "no MEM specified\n");
+ ret = -ENXIO;
+ goto exit_mem;
+ }
+
+ size = resource_size(res);
+
+ dd->io = request_mem_region(res->start, size, pdev->name);
+ if (dd->io == NULL) {
+ dev_err(_dev, "cannot reserve memory\n");
+ ret = -ENXIO;
+ goto exit_mem;
+ }
+
+ dd->base = ioremap(res->start, size);
+ if (dd->base == NULL) {
+ dev_err(_dev, "cannot ioremap region\n");
+ ret = -ENXIO;
+ goto exit_res;
+ }
+
+ dd->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(dd->clk)) {
+ dev_err(_dev, "Can not get device clock\n");
+ ret = -ENODEV;
+ goto exit_unmap;
+ }
+ clk_enable(dd->clk);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0)
+ irq = PARPORT_IRQ_NONE;
+
+ pp = parport_register_port((unsigned long)dd->base, irq,
+ PARPORT_DMA_NONE,
+ &parport_da8xx_ops);
+
+ if (pp == NULL) {
+ dev_err(_dev, "failed to register parallel port\n");
+ ret = -ENOMEM;
+ goto exit_clk_put;
+ }
+
+ pp->private_data = dd;
+ dd->parport = pp;
+ dd->dev = pp->dev = _dev;
+ dd->version = pdata->version;
+
+ if (dd->version == CONFIG_SPACE_0) {
+ dd->spp_data = dd->base + LCDC_LIDD_CS0_DATA;
+ dd->spp_cpr = dd->base + LCDC_LIDD_CS0_ADDR;
+ } else {
+ dd->spp_data = dd->base + LCDC_LIDD_CS1_DATA;
+ dd->spp_cpr = dd->base + LCDC_LIDD_CS1_ADDR;
+ }
+
+ /* initialize LCDC */
+ da8xx_init_clcd(pp);
+
+ if (irq >= 0) {
+ /* request irq */
+ ret = request_irq(irq, parport_irq_handler,
+ IRQF_TRIGGER_FALLING, pdev->name, pp);
+
+ if (ret < 0)
+ goto exit_port;
+
+ dd->irq_enabled = 1;
+ }
+
+ platform_set_drvdata(pdev, pp);
+
+ dev_info(_dev, "attached parallel port driver\n");
+ parport_announce_port(pp);
+
+ return 0;
+
+ exit_port:
+ parport_remove_port(pp);
+ exit_clk_put:
+ clk_disable(dd->clk);
+ clk_put(dd->clk);
+ exit_unmap:
+ iounmap(dd->base);
+ exit_res:
+ release_resource(dd->io);
+ kfree(dd->io);
+ exit_mem:
+ kfree(dd);
+ return ret;
+}
+
+static int parport_da8xx_remove(struct platform_device *pdev)
+{
+ struct parport *p = platform_get_drvdata(pdev);
+ struct da8xx_drvdata *dd = pp_to_drv(p);
+
+ free_irq(p->irq, p);
+ parport_remove_port(p);
+ clk_disable(dd->clk);
+ clk_put(dd->clk);
+ iounmap(dd->base);
+ release_resource(dd->io);
+ kfree(dd->io);
+ kfree(dd);
+
+ return 0;
+}
+
+MODULE_ALIAS("platform:da8xx_lcdc");
+
+static struct platform_driver da8xx_drv = {
+ .driver = {
+ .name = "da8xx_lcdc",
+ .owner = THIS_MODULE,
+ },
+ .probe = parport_da8xx_probe,
+ .remove = parport_da8xx_remove,
+};
+
+static int __init parport_da8xx_init(void)
+{
+ return platform_driver_register(&da8xx_drv);
+}
+
+static void __exit parport_da8xx_exit(void)
+{
+ platform_driver_unregister(&da8xx_drv);
+}
+
+module_init(parport_da8xx_init)
+module_exit(parport_da8xx_exit)
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("DA8xx/OMAP-L1xx Parport parallel port driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/parport_da8xx.h b/include/linux/parport_da8xx.h
new file mode 100644
index 0000000..53a01a3
--- /dev/null
+++ b/include/linux/parport_da8xx.h
@@ -0,0 +1,28 @@
+/*
+ * Header file for TI DA8XX/OMAP-L1XX LCD controller platform data.
+ *
+ * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * 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 version 2.
+ *
+ * This program is distributed .as is. WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef PARPORT_DA8XX_H
+#define PARPORT_DA8XX_H
+
+struct da8xx_clcd_platform_data {
+ u8 version;
+};
+
+enum {
+ CONFIG_SPACE_0 = 0, /* DA830 */
+ CONFIG_SPACE_1, /* DA850 */
+};
+
+#endif /* ifndef PARPORT_DA8XX_H */
--
1.5.6
Hi!
> On TI DA850/OMAP-L138 EVM, HD44780 (24x2) LCD panel is
> being used, interfaced through the SoC specific LCD
> interface[1].
>
> Driver from drivers/staging/panel/panel.c works for this
> LCD panel but that driver expects the LCD panel to be
> interfaced through a parallel port.
>
> This patch implements a dummy parallel port driver which
> interfaces to the panel driver in staging area through the
> LCD interface available on SoC.
This is a nasty hack, right? Just fixup panel.c to work with your
interface, too?
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
On Wed, 2 Sep 2009 19:23:27 +0530
"Sudhakar Rajashekhara" <[email protected]> wrote:
> On Tue, Sep 01, 2009 at 18:53:30, Pavel Machek wrote:
> > Hi!
> >
> > > On TI DA850/OMAP-L138 EVM, HD44780 (24x2) LCD panel is
> > > being used, interfaced through the SoC specific LCD
> > > interface[1].
> > >
> > > Driver from drivers/staging/panel/panel.c works for this
> > > LCD panel but that driver expects the LCD panel to be
> > > interfaced through a parallel port.
> > >
> > > This patch implements a dummy parallel port driver which
> > > interfaces to the panel driver in staging area through the
> > > LCD interface available on SoC.
> >
> > This is a nasty hack, right? Just fixup panel.c to work with your
> > interface, too?
> > Pavel
> >
>
> Agree, that this is a hack. I have submitted a patch which modifies
> panel.c to support this kind of interface.
>
> Currently the problem with panel.c is that, it is tightly coupled
> with parallel port interface. Panel driver needs to be completely
> re-written to de-couple parallel port related stuff. If I have to
> do this, then I need to start from ground zero as I do not have a
> setup on which HD44780 panel has been interfaced using parallel
> port. But I can certainly help here by testing such a modification
> to the panel driver by testing on the hardware what I have.
>
> In the meantime, can I re-submit this patch by moving the dummy
> parallel port driver to reside in staging area? Later it can be
> moved/deleted depending on the modifications to the panel driver.
>
If we're going to pull tricks like that then panel.c will never get
itself moved from outside staging/ :(
Really, I don't think we should be hacking things into drivers/parport/
code to accommodate design shortcomings in a staging/ driver. Once done,
these things have a tendency to never be undone.