2015-04-28 08:32:12

by Eddie Huang (黃智傑)

[permalink] [raw]
Subject: [PATCH v6 0/3] ARM: mediatek: Add driver for Mediatek I2C

This series is for Mediatek SoCs I2C controller common bus driver.

Earlier MTK SoC ((for example, MT6589, MT8135)) I2C HW has some limitationes.
New generation SoC like MT8173 fix following limitations:

1. Only support one i2c_msg number. One exception is WRRD (write then read)
mode. WRRD can have two i2c_msg numbers.

2. Mediatek I2C controller support WRRD(write then read) mode, in WRRD
mode the Repeat Start will be issued between 2 messages.
In this driver if 2 messages is first write then read, the driver will
combine 2 messages using Write-Read mode so the RS will be issued between
the 2 messages.

3. The max transfer data length is 255 in one message. In WRRD mode, the
max data length of second msg is 31.

MT8135 and MT6589 can control I2C pins on PMIC(MT6397) by setting the i2c
registers in MT8135 side. In this case, driver should set OFFSET_PATH_DIR
bit first, the operation on other registers are still the same.
For now MT6589/MT8135 support this, MT6577/MT6595/MT8127 do not support.
For example, If want to use I2C4/5/6 pins on MT8135 just need to enable
the pinmux, else if want to use I2C pins on PMIC(MT6397) need to add
"mediatek,have-pmic" property in the .dts file of each platform.

This driver is based on 4.1-rc1.

Change in v6:
1. Update binding document not use default clock-frequency as example.
2. Add mtk_i2c_compatible struct and pass hardware capabilities
through of_device_id
3. Remove some hardware setting in mtk_i2c_do_transfer to mtk_i2c_init_hw
so just init one time.
4. Correct mtk_i2c_parse_dt don't set default clock bug.

Change in v5:
Apply new i2c_adapter_quirks patch [2]. Change to use dam_map_single to map
dma buffer. Add spinlock to fix race condition. Check of_property_read_u32
return value. Remove I2C_FUNC_10BIT_ADDR capability due to driver not implement.
Add MT8173 I2C driver.

Change in v4:
Modify to support i2c_adapter_quirks base on Wolfram's patch [1].
Remove check transfer size and WRRD combine code. Instead, fill quirk
property and let i2c_check_for_quirks to do the filter.

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/314804.html
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/325744.html

Eddie Huang (1):
I2C: mediatek: Add driver for MediaTek MT8173 I2C controller

Xudong Chen (2):
dt-bindings: Add I2C bindings for mt65xx/mt81xx.
I2C: mediatek: Add driver for MediaTek I2C controller

.../devicetree/bindings/i2c/i2c-mt6577.txt | 41 ++
drivers/i2c/busses/Kconfig | 9 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-mt65xx.c | 748 +++++++++++++++++++++
4 files changed, 799 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
create mode 100644 drivers/i2c/busses/i2c-mt65xx.c

--
1.8.1.1.dirty


2015-04-28 08:31:34

by Eddie Huang (黃智傑)

[permalink] [raw]
Subject: [PATCH v6 1/3] dt-bindings: Add I2C bindings for mt65xx/mt81xx.

From: Xudong Chen <[email protected]>

Add devicetree bindings for Mediatek Soc I2C driver.

Signed-off-by: Xudong Chen <[email protected]>
Signed-off-by: Eddie Huang <[email protected]>
---
.../devicetree/bindings/i2c/i2c-mt6577.txt | 41 ++++++++++++++++++++++
1 file changed, 41 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
new file mode 100644
index 0000000..0ce6fa3
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
@@ -0,0 +1,41 @@
+* Mediatek's I2C controller
+
+The Mediatek's I2C controller is used to interface with I2C devices.
+
+Required properties:
+ - compatible: value should be either of the following.
+ (a) "mediatek,mt6577-i2c", for i2c compatible with mt6577 i2c.
+ (b) "mediatek,mt6589-i2c", for i2c compatible with mt6589 i2c.
+ (c) "mediatek,mt8127-i2c", for i2c compatible with mt8127 i2c.
+ (d) "mediatek,mt8135-i2c", for i2c compatible with mt8135 i2c.
+ (e) "mediatek,mt8173-i2c", for i2c compatible with mt8173 i2c.
+ - reg: physical base address of the controller and dma base, length of memory
+ mapped region.
+ - interrupts: interrupt number to the cpu.
+ - clock-div: the fixed value for frequency divider of clock source in i2c
+ module. Each IC may be different.
+ - clocks: clock name from clock manager
+ - clock-names: Must include "main" and "dma", if enable have-pmic need include
+ "pmic" extra.
+
+Optional properties:
+ - clock-frequency: Frequency in Hz of the bus when transfer, the default value
+ is 100000.
+ - mediatek,have-pmic: platform can control i2c form special pmic side.
+ Only mt6589 and mt8135 support this feature.
+ - mediatek,use-push-pull: IO config use push-pull mode.
+
+Example:
+
+ i2c0: i2c@1100d000 {
+ compatible = "mediatek,mt6577-i2c";
+ reg = <0x1100d000 0x70>,
+ <0x11000300 0x80>;
+ interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_LOW>;
+ clock-frequency = <400000>;
+ mediatek,have-pmic;
+ clock-div = <16>;
+ clocks = <&i2c0_ck>, <&ap_dma_ck>;
+ clock-names = "main", "dma";
+ };
+
--
1.8.1.1.dirty

2015-04-28 08:32:25

by Eddie Huang (黃智傑)

[permalink] [raw]
Subject: [PATCH v6 2/3] I2C: mediatek: Add driver for MediaTek I2C controller

From: Xudong Chen <[email protected]>

The mediatek SoCs have I2C controller that handle I2C transfer.
This patch include common I2C bus driver.
This driver is compatible with I2C controller on mt65xx/mt81xx.

Signed-off-by: Xudong Chen <[email protected]>
Signed-off-by: Liguo Zhang <[email protected]>
Signed-off-by: Eddie Huang <[email protected]>
---
drivers/i2c/busses/Kconfig | 9 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-mt65xx.c | 700 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 710 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-mt65xx.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 2255af2..14c7266 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -620,6 +620,15 @@ config I2C_MPC
This driver can also be built as a module. If so, the module
will be called i2c-mpc.

+config I2C_MT65XX
+ tristate "MediaTek I2C adapter"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ help
+ This selects the MediaTek(R) Integrated Inter Circuit bus driver
+ for MT65xx and MT81xx.
+ If you want to use MediaTek(R) I2C interface, say Y or M here.
+ If unsure, say N.
+
config I2C_MV64XXX
tristate "Marvell mv64xxx I2C Controller"
depends on MV64X60 || PLAT_ORION || ARCH_SUNXI
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index cdf941d..abbf422 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o
obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o
obj-$(CONFIG_I2C_MESON) += i2c-meson.o
obj-$(CONFIG_I2C_MPC) += i2c-mpc.o
+obj-$(CONFIG_I2C_MT65XX) += i2c-mt65xx.o
obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o
obj-$(CONFIG_I2C_MXS) += i2c-mxs.o
obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
new file mode 100644
index 0000000..2ecf0d1
--- /dev/null
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -0,0 +1,700 @@
+/*
+ * Copyright (c) 2014 MediaTek Inc.
+ * Author: Xudong.chen <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+
+#define I2C_HS_NACKERR (1 << 2)
+#define I2C_ACKERR (1 << 1)
+#define I2C_TRANSAC_COMP (1 << 0)
+#define I2C_TRANSAC_START (1 << 0)
+#define I2C_TIMING_STEP_DIV_MASK (0x3f << 0)
+#define I2C_TIMING_SAMPLE_COUNT_MASK (0x7 << 0)
+#define I2C_TIMING_SAMPLE_DIV_MASK (0x7 << 8)
+#define I2C_TIMING_DATA_READ_MASK (0x7 << 12)
+#define I2C_DCM_DISABLE 0x0000
+#define I2C_IO_CONFIG_OPEN_DRAIN 0x0003
+#define I2C_IO_CONFIG_PUSH_PULL 0x0000
+#define I2C_SOFT_RST 0x0001
+#define I2C_FIFO_ADDR_CLR 0x0001
+#define I2C_DELAY_LEN 0x0002
+#define I2C_ST_START_CON 0x8001
+#define I2C_FS_START_CON 0x1800
+#define I2C_TIME_CLR_VALUE 0x0000
+#define I2C_TIME_DEFAULT_VALUE 0x0003
+#define I2C_FS_TIME_INIT_VALUE 0x1303
+#define I2C_WRRD_TRANAC_VALUE 0x0002
+#define I2C_RD_TRANAC_VALUE 0x0001
+
+#define I2C_DMA_CON_TX 0x0000
+#define I2C_DMA_CON_RX 0x0001
+#define I2C_DMA_START_EN 0x0001
+#define I2C_DMA_INT_FLAG_NONE 0x0000
+#define I2C_DMA_CLR_FLAG 0x0000
+
+#define I2C_DEFAUT_SPEED 100000 /* hz */
+#define MAX_FS_MODE_SPEED 400000
+#define MAX_HS_MODE_SPEED 3400000
+#define MAX_MSG_NUM_MT6577 1
+#define MAX_DMA_TRANS_SIZE_MT6577 255
+#define MAX_WRRD_TRANS_SIZE_MT6577 31
+#define MAX_SAMPLE_CNT_DIV 8
+#define MAX_STEP_CNT_DIV 64
+#define MAX_HS_STEP_CNT_DIV 8
+
+#define I2C_CONTROL_RS (0x1 << 1)
+#define I2C_CONTROL_DMA_EN (0x1 << 2)
+#define I2C_CONTROL_CLK_EXT_EN (0x1 << 3)
+#define I2C_CONTROL_DIR_CHANGE (0x1 << 4)
+#define I2C_CONTROL_ACKERR_DET_EN (0x1 << 5)
+#define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6)
+#define I2C_CONTROL_WRAPPER (0x1 << 0)
+
+#define I2C_DRV_NAME "mt-i2c"
+
+enum DMA_REGS_OFFSET {
+ OFFSET_INT_FLAG = 0x0,
+ OFFSET_INT_EN = 0x04,
+ OFFSET_EN = 0x08,
+ OFFSET_CON = 0x18,
+ OFFSET_TX_MEM_ADDR = 0x1c,
+ OFFSET_RX_MEM_ADDR = 0x20,
+ OFFSET_TX_LEN = 0x24,
+ OFFSET_RX_LEN = 0x28,
+};
+
+enum i2c_trans_st_rs {
+ I2C_TRANS_STOP = 0,
+ I2C_TRANS_REPEATED_START,
+};
+
+enum mtk_trans_op {
+ I2C_MASTER_WR = 1,
+ I2C_MASTER_RD,
+ I2C_MASTER_WRRD,
+};
+
+enum I2C_REGS_OFFSET {
+ OFFSET_DATA_PORT = 0x0,
+ OFFSET_SLAVE_ADDR = 0x04,
+ OFFSET_INTR_MASK = 0x08,
+ OFFSET_INTR_STAT = 0x0c,
+ OFFSET_CONTROL = 0x10,
+ OFFSET_TRANSFER_LEN = 0x14,
+ OFFSET_TRANSAC_LEN = 0x18,
+ OFFSET_DELAY_LEN = 0x1c,
+ OFFSET_TIMING = 0x20,
+ OFFSET_START = 0x24,
+ OFFSET_EXT_CONF = 0x28,
+ OFFSET_FIFO_STAT = 0x30,
+ OFFSET_FIFO_THRESH = 0x34,
+ OFFSET_FIFO_ADDR_CLR = 0x38,
+ OFFSET_IO_CONFIG = 0x40,
+ OFFSET_RSV_DEBUG = 0x44,
+ OFFSET_HS = 0x48,
+ OFFSET_SOFTRESET = 0x50,
+ OFFSET_DCM_EN = 0x54,
+ OFFSET_PATH_DIR = 0x60,
+ OFFSET_DEBUGSTAT = 0x64,
+ OFFSET_DEBUGCTRL = 0x68,
+ OFFSET_TRANSFER_LEN_AUX = 0x6c,
+};
+
+struct mtk_i2c_data {
+ unsigned int clk_frequency; /* bus speed in Hz */
+ unsigned int flags;
+ unsigned int clk_src_div;
+};
+
+struct mtk_i2c_compatible {
+ const struct i2c_adapter_quirks *quirks;
+ unsigned char pmic_i2c;
+ unsigned char dcm;
+};
+
+struct mtk_i2c {
+ struct i2c_adapter adap; /* i2c host adapter */
+ struct device *dev;
+ struct completion msg_complete;
+
+ /* set in i2c probe */
+ void __iomem *base; /* i2c base addr */
+ void __iomem *pdmabase; /* dma base address*/
+ struct clk *clk_main; /* main clock for i2c bus */
+ struct clk *clk_dma; /* DMA clock for i2c via DMA */
+ struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */
+ bool have_pmic; /* can use i2c pins from PMIC */
+ bool use_push_pull; /* IO config push-pull mode */
+
+ u16 irq_stat; /* interrupt status */
+ unsigned int speed_hz; /* The speed in transfer */
+ enum mtk_trans_op op;
+ u16 timing_reg;
+ u16 high_speed_reg;
+ const struct mtk_i2c_compatible *dev_comp;
+};
+
+static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
+ .flags = I2C_AQ_COMB_WRITE_THEN_READ,
+ .max_num_msgs = MAX_MSG_NUM_MT6577,
+ .max_write_len = MAX_DMA_TRANS_SIZE_MT6577,
+ .max_read_len = MAX_DMA_TRANS_SIZE_MT6577,
+ .max_comb_1st_msg_len = MAX_DMA_TRANS_SIZE_MT6577,
+ .max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT6577,
+};
+
+static const struct mtk_i2c_compatible mt6577_compat = {
+ .quirks = &mt6577_i2c_quirks,
+ .pmic_i2c = 0,
+ .dcm = 1,
+};
+
+static const struct mtk_i2c_compatible mt6589_compat = {
+ .quirks = &mt6577_i2c_quirks,
+ .pmic_i2c = 1,
+ .dcm = 0,
+};
+
+static const struct of_device_id mtk_i2c_of_match[] = {
+ { .compatible = "mediatek,mt6577-i2c", .data = (void *)&mt6577_compat },
+ { .compatible = "mediatek,mt6589-i2c", .data = (void *)&mt6589_compat },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mtk_i2c_match);
+
+static inline void mtk_i2c_writew(u16 value, struct mtk_i2c *i2c, u8 offset)
+{
+ writew(value, i2c->base + offset);
+}
+
+static inline u16 mtk_i2c_readw(struct mtk_i2c *i2c, u8 offset)
+{
+ return readw(i2c->base + offset);
+}
+
+static inline void mtk_i2c_writel_dma(u32 value, struct mtk_i2c *i2c, u8 offset)
+{
+ writel(value, i2c->pdmabase + offset);
+}
+
+static int mtk_i2c_clock_enable(struct mtk_i2c *i2c)
+{
+ int ret;
+
+ ret = clk_prepare_enable(i2c->clk_dma);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(i2c->clk_main);
+ if (ret)
+ goto err_main;
+
+ if (i2c->have_pmic) {
+ ret = clk_prepare_enable(i2c->clk_pmic);
+ if (ret)
+ goto err_pmic;
+ }
+ return 0;
+
+err_pmic:
+ clk_disable_unprepare(i2c->clk_main);
+err_main:
+ clk_disable_unprepare(i2c->clk_dma);
+
+ return ret;
+}
+
+static void mtk_i2c_clock_disable(struct mtk_i2c *i2c)
+{
+ if (i2c->have_pmic)
+ clk_disable_unprepare(i2c->clk_pmic);
+
+ clk_disable_unprepare(i2c->clk_main);
+ clk_disable_unprepare(i2c->clk_dma);
+}
+
+static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
+{
+ u16 control_reg;
+
+ mtk_i2c_writew(I2C_SOFT_RST, i2c, OFFSET_SOFTRESET);
+ /* Set ioconfig */
+ if (i2c->use_push_pull)
+ mtk_i2c_writew(I2C_IO_CONFIG_PUSH_PULL, i2c, OFFSET_IO_CONFIG);
+ else
+ mtk_i2c_writew(I2C_IO_CONFIG_OPEN_DRAIN, i2c, OFFSET_IO_CONFIG);
+
+ if (i2c->dev_comp->dcm)
+ mtk_i2c_writew(I2C_DCM_DISABLE, i2c, OFFSET_DCM_EN);
+
+ mtk_i2c_writew(i2c->timing_reg, i2c, OFFSET_TIMING);
+ mtk_i2c_writew(i2c->high_speed_reg, i2c, OFFSET_HS);
+
+ /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */
+ if (i2c->have_pmic)
+ mtk_i2c_writew(I2C_CONTROL_WRAPPER, i2c, OFFSET_PATH_DIR);
+
+ control_reg = I2C_CONTROL_ACKERR_DET_EN |
+ I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
+ mtk_i2c_writew(control_reg, i2c, OFFSET_CONTROL);
+ mtk_i2c_writew(I2C_DELAY_LEN, i2c, OFFSET_DELAY_LEN);
+}
+
+/* calculate i2c port speed */
+static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int clk_src_in_hz)
+{
+ unsigned int khz;
+ unsigned int step_cnt;
+ unsigned int sample_cnt;
+ unsigned int sclk;
+ unsigned int hclk;
+ unsigned int max_step_cnt;
+ unsigned int sample_div = MAX_SAMPLE_CNT_DIV;
+ unsigned int step_div;
+ unsigned int min_div;
+ unsigned int best_mul;
+ unsigned int cnt_mul;
+
+ if (i2c->speed_hz > MAX_HS_MODE_SPEED)
+ return -EINVAL;
+ else if (i2c->speed_hz > MAX_FS_MODE_SPEED)
+ max_step_cnt = MAX_HS_STEP_CNT_DIV;
+ else
+ max_step_cnt = MAX_STEP_CNT_DIV;
+
+ step_div = max_step_cnt;
+ /* Find the best combination */
+ khz = i2c->speed_hz / 1000;
+ hclk = clk_src_in_hz / 1000;
+ min_div = ((hclk >> 1) + khz - 1) / khz;
+ best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt;
+
+ for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) {
+ step_cnt = (min_div + sample_cnt - 1) / sample_cnt;
+ cnt_mul = step_cnt * sample_cnt;
+ if (step_cnt > max_step_cnt)
+ continue;
+
+ if (cnt_mul < best_mul) {
+ best_mul = cnt_mul;
+ sample_div = sample_cnt;
+ step_div = step_cnt;
+ if (best_mul == min_div)
+ break;
+ }
+ }
+
+ sample_cnt = sample_div;
+ step_cnt = step_div;
+ sclk = hclk / (2 * sample_cnt * step_cnt);
+ if (sclk > khz) {
+ dev_dbg(i2c->dev, "%s mode: unsupported speed (%ldkhz)\n",
+ (i2c->speed_hz > MAX_HS_MODE_SPEED) ? "HS" : "ST/FT",
+ (long int)khz);
+ return -ENOTSUPP;
+ }
+
+ step_cnt--;
+ sample_cnt--;
+
+ if (i2c->speed_hz > MAX_FS_MODE_SPEED) {
+ /* Set the hign speed mode register */
+ i2c->timing_reg = I2C_FS_TIME_INIT_VALUE;
+ i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE |
+ (sample_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 12 |
+ (step_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 8;
+ } else {
+ i2c->timing_reg =
+ (sample_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 8 |
+ (step_cnt & I2C_TIMING_STEP_DIV_MASK) << 0;
+ /* Disable the high speed transaction */
+ i2c->high_speed_reg = I2C_TIME_CLR_VALUE;
+ }
+
+ return 0;
+}
+
+static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
+{
+ u16 addr_reg;
+ u16 control_reg;
+ dma_addr_t rpaddr = 0;
+ dma_addr_t wpaddr = 0;
+ int ret;
+
+ i2c->irq_stat = 0;
+
+ reinit_completion(&i2c->msg_complete);
+
+ control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) &
+ ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS);
+ if (i2c->speed_hz > 400000)
+ control_reg |= I2C_CONTROL_RS;
+ if (i2c->op == I2C_MASTER_WRRD)
+ control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
+ mtk_i2c_writew(control_reg, i2c, OFFSET_CONTROL);
+
+ /* set start condition */
+ if (i2c->speed_hz <= 100000)
+ mtk_i2c_writew(I2C_ST_START_CON, i2c, OFFSET_EXT_CONF);
+ else
+ mtk_i2c_writew(I2C_FS_START_CON, i2c, OFFSET_EXT_CONF);
+
+ addr_reg = msgs->addr << 1;
+ if (i2c->op == I2C_MASTER_RD)
+ addr_reg |= 0x1;
+ mtk_i2c_writew(addr_reg, i2c, OFFSET_SLAVE_ADDR);
+
+ /* Clear interrupt status */
+ mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
+ i2c, OFFSET_INTR_STAT);
+ mtk_i2c_writew(I2C_FIFO_ADDR_CLR, i2c, OFFSET_FIFO_ADDR_CLR);
+
+ /* Enable interrupt */
+ mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
+ i2c, OFFSET_INTR_MASK);
+
+ /* Set transfer and transaction len */
+ if (i2c->op == I2C_MASTER_WRRD) {
+ mtk_i2c_writew(msgs->len | ((msgs + 1)->len) << 8,
+ i2c, OFFSET_TRANSFER_LEN);
+ mtk_i2c_writew(I2C_WRRD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
+ } else {
+ mtk_i2c_writew(msgs->len, i2c, OFFSET_TRANSFER_LEN);
+ mtk_i2c_writew(I2C_RD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
+ }
+
+ /* Prepare buffer data to start transfer */
+ if (i2c->op == I2C_MASTER_RD) {
+ mtk_i2c_writel_dma(I2C_DMA_INT_FLAG_NONE, i2c, OFFSET_INT_FLAG);
+ mtk_i2c_writel_dma(I2C_DMA_CON_RX, i2c, OFFSET_CON);
+ rpaddr = dma_map_single(i2c->adap.dev.parent, msgs->buf,
+ msgs->len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(i2c->adap.dev.parent, rpaddr))
+ return -ENOMEM;
+ mtk_i2c_writel_dma((u32)rpaddr, i2c, OFFSET_RX_MEM_ADDR);
+ mtk_i2c_writel_dma(msgs->len, i2c, OFFSET_RX_LEN);
+ } else if (i2c->op == I2C_MASTER_WR) {
+ mtk_i2c_writel_dma(I2C_DMA_INT_FLAG_NONE, i2c, OFFSET_INT_FLAG);
+ mtk_i2c_writel_dma(I2C_DMA_CON_TX, i2c, OFFSET_CON);
+ wpaddr = dma_map_single(i2c->adap.dev.parent, msgs->buf,
+ msgs->len, DMA_TO_DEVICE);
+ if (dma_mapping_error(i2c->adap.dev.parent, wpaddr))
+ return -ENOMEM;
+ mtk_i2c_writel_dma((u32)wpaddr, i2c, OFFSET_TX_MEM_ADDR);
+ mtk_i2c_writel_dma(msgs->len, i2c, OFFSET_TX_LEN);
+ } else {
+ mtk_i2c_writel_dma(I2C_DMA_CLR_FLAG, i2c, OFFSET_INT_FLAG);
+ mtk_i2c_writel_dma(I2C_DMA_CLR_FLAG, i2c, OFFSET_CON);
+ wpaddr = dma_map_single(i2c->adap.dev.parent, msgs->buf,
+ msgs->len, DMA_TO_DEVICE);
+ if (dma_mapping_error(i2c->adap.dev.parent, wpaddr))
+ return -ENOMEM;
+ rpaddr = dma_map_single(i2c->adap.dev.parent, (msgs + 1)->buf,
+ (msgs + 1)->len,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(i2c->adap.dev.parent, rpaddr)) {
+ dma_unmap_single(i2c->adap.dev.parent, wpaddr,
+ msgs->len, DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+ mtk_i2c_writel_dma((u32)wpaddr, i2c, OFFSET_TX_MEM_ADDR);
+ mtk_i2c_writel_dma((u32)rpaddr, i2c, OFFSET_RX_MEM_ADDR);
+ mtk_i2c_writel_dma(msgs->len, i2c, OFFSET_TX_LEN);
+ mtk_i2c_writel_dma((msgs + 1)->len, i2c, OFFSET_RX_LEN);
+ }
+
+ /* flush before sending start */
+ mb();
+ mtk_i2c_writel_dma(I2C_DMA_START_EN, i2c, OFFSET_EN);
+ mtk_i2c_writew(I2C_TRANSAC_START, i2c, OFFSET_START);
+
+ ret = wait_for_completion_timeout(&i2c->msg_complete,
+ i2c->adap.timeout);
+
+ /* Clear interrupt mask */
+ mtk_i2c_writew(~(I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP), i2c, OFFSET_INTR_MASK);
+
+ if (i2c->op == I2C_MASTER_WR) {
+ dma_unmap_single(i2c->adap.dev.parent, wpaddr,
+ msgs->len, DMA_TO_DEVICE);
+ } else if (i2c->op == I2C_MASTER_RD) {
+ dma_unmap_single(i2c->adap.dev.parent, rpaddr,
+ msgs->len, DMA_FROM_DEVICE);
+ } else {
+ dma_unmap_single(i2c->adap.dev.parent, wpaddr, msgs->len,
+ DMA_TO_DEVICE);
+ dma_unmap_single(i2c->adap.dev.parent, rpaddr, (msgs + 1)->len,
+ DMA_FROM_DEVICE);
+ }
+
+ if (ret == 0) {
+ dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr);
+ mtk_i2c_init_hw(i2c);
+ return -ETIMEDOUT;
+ }
+
+ completion_done(&i2c->msg_complete);
+
+ if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) {
+ dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr);
+ mtk_i2c_init_hw(i2c);
+ return -EREMOTEIO;
+ }
+
+ return 0;
+}
+
+static int mtk_i2c_transfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ int ret;
+ int left_num = num;
+ struct mtk_i2c *i2c = i2c_get_adapdata(adap);
+
+ ret = mtk_i2c_clock_enable(i2c);
+ if (ret)
+ return ret;
+
+ if (msgs->buf == NULL) {
+ dev_dbg(i2c->dev, "data buffer is NULL.\n");
+ ret = -EINVAL;
+ goto err_exit;
+ }
+
+ if (msgs->flags & I2C_M_RD)
+ i2c->op = I2C_MASTER_RD;
+ else
+ i2c->op = I2C_MASTER_WR;
+
+ if (num > 1) {
+ /* combined two messages into one transaction */
+ i2c->op = I2C_MASTER_WRRD;
+ left_num--;
+ }
+
+ /* always use DMA mode. */
+ ret = mtk_i2c_do_transfer(i2c, msgs);
+ if (ret < 0)
+ goto err_exit;
+
+ /* the return value is number of executed messages */
+ ret = num;
+
+err_exit:
+ mtk_i2c_clock_disable(i2c);
+ return ret;
+}
+
+static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
+{
+ struct mtk_i2c *i2c = dev_id;
+
+ i2c->irq_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
+ mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP, i2c, OFFSET_INTR_STAT);
+
+ complete(&i2c->msg_complete);
+
+ return IRQ_HANDLED;
+}
+
+static u32 mtk_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm mtk_i2c_algorithm = {
+ .master_xfer = mtk_i2c_transfer,
+ .functionality = mtk_i2c_functionality,
+};
+
+static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c,
+ unsigned int *clk_src_div)
+{
+ int ret;
+
+ ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz);
+ if (ret < 0)
+ i2c->speed_hz = I2C_DEFAUT_SPEED;
+
+ ret = of_property_read_u32(np, "clock-div", clk_src_div);
+ if (ret < 0)
+ return ret;
+
+ if (*clk_src_div == 0)
+ return -EINVAL;
+
+ i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic");
+ i2c->use_push_pull =
+ of_property_read_bool(np, "mediatek,use-push-pull");
+
+ return 0;
+}
+
+static int mtk_i2c_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id;
+ int ret = 0;
+ struct mtk_i2c *i2c;
+ struct clk *clk;
+ unsigned int clk_src_in_hz;
+ unsigned int clk_src_div;
+ struct resource *res;
+ int irq;
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+ if (i2c == NULL)
+ return -ENOMEM;
+
+ ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c, &clk_src_div);
+ if (ret)
+ return -EINVAL;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ i2c->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(i2c->base))
+ return PTR_ERR(i2c->base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ i2c->pdmabase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(i2c->pdmabase))
+ return PTR_ERR(i2c->pdmabase);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0)
+ return irq;
+
+ init_completion(&i2c->msg_complete);
+
+ of_id = of_match_node(mtk_i2c_of_match, pdev->dev.of_node);
+ if (!of_id)
+ return -EINVAL;
+
+ i2c->dev_comp = of_id->data;
+ i2c->adap.dev.of_node = pdev->dev.of_node;
+ i2c->dev = &i2c->adap.dev;
+ i2c->adap.dev.parent = &pdev->dev;
+ i2c->adap.owner = THIS_MODULE;
+ i2c->adap.algo = &mtk_i2c_algorithm;
+ i2c->adap.quirks = i2c->dev_comp->quirks;
+ i2c->adap.timeout = 2 * HZ;
+ i2c->adap.retries = 1;
+
+ if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c)
+ return -EINVAL;
+
+ i2c->clk_main = devm_clk_get(&pdev->dev, "main");
+ if (IS_ERR(i2c->clk_main)) {
+ dev_err(&pdev->dev, "cannot get main clock\n");
+ return PTR_ERR(i2c->clk_main);
+ }
+
+ i2c->clk_dma = devm_clk_get(&pdev->dev, "dma");
+ if (IS_ERR(i2c->clk_dma)) {
+ dev_err(&pdev->dev, "cannot get dma clock\n");
+ return PTR_ERR(i2c->clk_dma);
+ }
+
+ clk = i2c->clk_main;
+ if (i2c->have_pmic) {
+ i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic");
+ if (IS_ERR(i2c->clk_pmic)) {
+ dev_err(&pdev->dev, "cannot get pmic clock\n");
+ return PTR_ERR(i2c->clk_pmic);
+ }
+ clk = i2c->clk_pmic;
+ }
+ clk_src_in_hz = clk_get_rate(clk) / clk_src_div;
+
+ dev_dbg(&pdev->dev, "clock source %p,clock src frequency %d\n",
+ i2c->clk_main, clk_src_in_hz);
+ strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name));
+
+ ret = mtk_i2c_set_speed(i2c, clk_src_in_hz);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to set the speed.\n");
+ return -EINVAL;
+ }
+
+ ret = mtk_i2c_clock_enable(i2c);
+ if (ret) {
+ dev_err(&pdev->dev, "clock enable failed!\n");
+ return ret;
+ }
+ mtk_i2c_init_hw(i2c);
+ mtk_i2c_clock_disable(i2c);
+
+ ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq,
+ IRQF_TRIGGER_NONE, I2C_DRV_NAME, i2c);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Request I2C IRQ %d fail\n", irq);
+ return ret;
+ }
+
+ i2c_set_adapdata(&i2c->adap, i2c);
+ ret = i2c_add_adapter(&i2c->adap);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to add i2c bus to i2c core\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, i2c);
+
+ return 0;
+}
+
+static int mtk_i2c_remove(struct platform_device *pdev)
+{
+ struct mtk_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+
+ return 0;
+}
+
+static struct platform_driver mtk_i2c_driver = {
+ .probe = mtk_i2c_probe,
+ .remove = mtk_i2c_remove,
+ .driver = {
+ .name = I2C_DRV_NAME,
+ .of_match_table = of_match_ptr(mtk_i2c_of_match),
+ },
+};
+
+module_platform_driver(mtk_i2c_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek I2C Bus Driver");
+MODULE_AUTHOR("Xudong Chen <[email protected]>");
--
1.8.1.1.dirty

2015-04-28 08:31:40

by Eddie Huang (黃智傑)

[permalink] [raw]
Subject: [PATCH v6 3/3] I2C: mediatek: Add driver for MediaTek MT8173 I2C controller

Add mediatek MT8173 I2C controller driver. Compare to I2C controller
of earlier mediatek SoC, MT8173 fix write-then-read limitation, and
also increase message size to 64kb.

Signed-off-by: Xudong Chen <[email protected]>
Signed-off-by: Liguo Zhang <[email protected]>
Signed-off-by: Eddie Huang <[email protected]>
---
drivers/i2c/busses/i2c-mt65xx.c | 106 +++++++++++++++++++++++++++++-----------
1 file changed, 77 insertions(+), 29 deletions(-)

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 2ecf0d1..c501421 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -33,10 +33,13 @@
#include <linux/clk.h>
#include <linux/completion.h>

+#define I2C_RS_TRANSFER (1 << 4)
#define I2C_HS_NACKERR (1 << 2)
#define I2C_ACKERR (1 << 1)
#define I2C_TRANSAC_COMP (1 << 0)
#define I2C_TRANSAC_START (1 << 0)
+#define I2C_RS_MUL_CNFG (1 << 15)
+#define I2C_RS_MUL_TRIG (1 << 14)
#define I2C_TIMING_STEP_DIV_MASK (0x3f << 0)
#define I2C_TIMING_SAMPLE_COUNT_MASK (0x7 << 0)
#define I2C_TIMING_SAMPLE_DIV_MASK (0x7 << 8)
@@ -67,6 +70,9 @@
#define MAX_MSG_NUM_MT6577 1
#define MAX_DMA_TRANS_SIZE_MT6577 255
#define MAX_WRRD_TRANS_SIZE_MT6577 31
+#define MAX_MSG_NUM_MT8173 65535
+#define MAX_DMA_TRANS_SIZE_MT8173 65535
+#define MAX_WRRD_TRANS_SIZE_MT8173 65535
#define MAX_SAMPLE_CNT_DIV 8
#define MAX_STEP_CNT_DIV 64
#define MAX_HS_STEP_CNT_DIV 8
@@ -139,6 +145,7 @@ struct mtk_i2c_compatible {
const struct i2c_adapter_quirks *quirks;
unsigned char pmic_i2c;
unsigned char dcm;
+ unsigned char auto_restart;
};

struct mtk_i2c {
@@ -172,24 +179,42 @@ static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
.max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT6577,
};

+static const struct i2c_adapter_quirks mt8173_i2c_quirks = {
+ .max_num_msgs = MAX_MSG_NUM_MT8173,
+ .max_write_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_read_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_comb_1st_msg_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT8173,
+};
+
static const struct mtk_i2c_compatible mt6577_compat = {
.quirks = &mt6577_i2c_quirks,
.pmic_i2c = 0,
.dcm = 1,
+ .auto_restart = 0,
};

static const struct mtk_i2c_compatible mt6589_compat = {
.quirks = &mt6577_i2c_quirks,
.pmic_i2c = 1,
.dcm = 0,
+ .auto_restart = 0,
+};
+
+static const struct mtk_i2c_compatible mt8173_compat = {
+ .quirks = &mt8173_i2c_quirks,
+ .pmic_i2c = 0,
+ .dcm = 1,
+ .auto_restart = 1,
};

static const struct of_device_id mtk_i2c_of_match[] = {
{ .compatible = "mediatek,mt6577-i2c", .data = (void *)&mt6577_compat },
{ .compatible = "mediatek,mt6589-i2c", .data = (void *)&mt6589_compat },
+ { .compatible = "mediatek,mt8173-i2c", .data = (void *)&mt8173_compat },
{}
};
-MODULE_DEVICE_TABLE(of, mtk_i2c_match);
+MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);

static inline void mtk_i2c_writew(u16 value, struct mtk_i2c *i2c, u8 offset)
{
@@ -343,9 +368,11 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int clk_src_in_hz)
return 0;
}

-static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
+static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
+ int num, int left_num)
{
u16 addr_reg;
+ u16 start_reg;
u16 control_reg;
dma_addr_t rpaddr = 0;
dma_addr_t wpaddr = 0;
@@ -361,6 +388,8 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
control_reg |= I2C_CONTROL_RS;
if (i2c->op == I2C_MASTER_WRRD)
control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
+ if (left_num >= 1)
+ control_reg |= I2C_CONTROL_RS;
mtk_i2c_writew(control_reg, i2c, OFFSET_CONTROL);

/* set start condition */
@@ -375,13 +404,13 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
mtk_i2c_writew(addr_reg, i2c, OFFSET_SLAVE_ADDR);

/* Clear interrupt status */
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
- i2c, OFFSET_INTR_STAT);
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP, i2c, OFFSET_INTR_STAT);
mtk_i2c_writew(I2C_FIFO_ADDR_CLR, i2c, OFFSET_FIFO_ADDR_CLR);

/* Enable interrupt */
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
- i2c, OFFSET_INTR_MASK);
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP, i2c, OFFSET_INTR_MASK);

/* Set transfer and transaction len */
if (i2c->op == I2C_MASTER_WRRD) {
@@ -390,7 +419,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
mtk_i2c_writew(I2C_WRRD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
} else {
mtk_i2c_writew(msgs->len, i2c, OFFSET_TRANSFER_LEN);
- mtk_i2c_writew(I2C_RD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
+ mtk_i2c_writew(num, i2c, OFFSET_TRANSAC_LEN);
}

/* Prepare buffer data to start transfer */
@@ -436,13 +465,23 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
/* flush before sending start */
mb();
mtk_i2c_writel_dma(I2C_DMA_START_EN, i2c, OFFSET_EN);
- mtk_i2c_writew(I2C_TRANSAC_START, i2c, OFFSET_START);
+
+ if (!i2c->dev_comp->auto_restart) {
+ start_reg = I2C_TRANSAC_START;
+ } else {
+ if (left_num >= 1)
+ start_reg = I2C_TRANSAC_START | I2C_RS_MUL_CNFG
+ | I2C_RS_MUL_TRIG;
+ else
+ start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG;
+ }
+ mtk_i2c_writew(start_reg, i2c, OFFSET_START);

ret = wait_for_completion_timeout(&i2c->msg_complete,
i2c->adap.timeout);

/* Clear interrupt mask */
- mtk_i2c_writew(~(I2C_HS_NACKERR | I2C_ACKERR
+ mtk_i2c_writew(~(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
| I2C_TRANSAC_COMP), i2c, OFFSET_INTR_MASK);

if (i2c->op == I2C_MASTER_WR) {
@@ -472,6 +511,10 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
return -EREMOTEIO;
}

+ if (i2c->irq_stat & I2C_RS_TRANSFER)
+ dev_dbg(i2c->dev, "addr: %x, restart transfer interrupt.\n",
+ msgs->addr);
+
return 0;
}

@@ -486,28 +529,33 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap,
if (ret)
return ret;

- if (msgs->buf == NULL) {
- dev_dbg(i2c->dev, "data buffer is NULL.\n");
- ret = -EINVAL;
- goto err_exit;
- }
-
- if (msgs->flags & I2C_M_RD)
- i2c->op = I2C_MASTER_RD;
- else
- i2c->op = I2C_MASTER_WR;
+ while (left_num--) {
+ if (msgs->buf == NULL) {
+ dev_dbg(i2c->dev, "data buffer is NULL.\n");
+ ret = -EINVAL;
+ goto err_exit;
+ }

- if (num > 1) {
- /* combined two messages into one transaction */
- i2c->op = I2C_MASTER_WRRD;
- left_num--;
- }
+ if (msgs->flags & I2C_M_RD)
+ i2c->op = I2C_MASTER_RD;
+ else
+ i2c->op = I2C_MASTER_WR;
+
+ if (!i2c->dev_comp->auto_restart) {
+ if (num > 1) {
+ /* combined two messages into one transaction */
+ i2c->op = I2C_MASTER_WRRD;
+ left_num--;
+ }
+ }

- /* always use DMA mode. */
- ret = mtk_i2c_do_transfer(i2c, msgs);
- if (ret < 0)
- goto err_exit;
+ /* always use DMA mode. */
+ ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num);
+ if (ret < 0)
+ goto err_exit;

+ msgs++;
+ }
/* the return value is number of executed messages */
ret = num;

@@ -521,7 +569,7 @@ static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
struct mtk_i2c *i2c = dev_id;

i2c->irq_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
| I2C_TRANSAC_COMP, i2c, OFFSET_INTR_STAT);

complete(&i2c->msg_complete);
--
1.8.1.1.dirty

2015-04-28 08:37:45

by Marc Kleine-Budde

[permalink] [raw]
Subject: Re: [PATCH v6 3/3] I2C: mediatek: Add driver for MediaTek MT8173 I2C controller

On 04/28/2015 10:31 AM, Eddie Huang wrote:
> Add mediatek MT8173 I2C controller driver. Compare to I2C controller
> of earlier mediatek SoC, MT8173 fix write-then-read limitation, and
> also increase message size to 64kb.
>
> Signed-off-by: Xudong Chen <[email protected]>
> Signed-off-by: Liguo Zhang <[email protected]>
> Signed-off-by: Eddie Huang <[email protected]>
> ---
> drivers/i2c/busses/i2c-mt65xx.c | 106 +++++++++++++++++++++++++++++-----------
> 1 file changed, 77 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
> index 2ecf0d1..c501421 100644
> --- a/drivers/i2c/busses/i2c-mt65xx.c
> +++ b/drivers/i2c/busses/i2c-mt65xx.c
[...]

> static const struct of_device_id mtk_i2c_of_match[] = {
> { .compatible = "mediatek,mt6577-i2c", .data = (void *)&mt6577_compat },
> { .compatible = "mediatek,mt6589-i2c", .data = (void *)&mt6589_compat },
> + { .compatible = "mediatek,mt8173-i2c", .data = (void *)&mt8173_compat },
> {}
> };
> -MODULE_DEVICE_TABLE(of, mtk_i2c_match);
> +MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);

This should go into the previous patch, as 2/3 will probably not compile
without this change.

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |


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2015-04-28 08:45:01

by Eddie Huang (黃智傑)

[permalink] [raw]
Subject: Re: [PATCH v6 3/3] I2C: mediatek: Add driver for MediaTek MT8173 I2C controller

Hi Marc,

On Tue, 2015-04-28 at 10:36 +0200, Marc Kleine-Budde wrote:
> On 04/28/2015 10:31 AM, Eddie Huang wrote:
> > Add mediatek MT8173 I2C controller driver. Compare to I2C controller
> > of earlier mediatek SoC, MT8173 fix write-then-read limitation, and
> > also increase message size to 64kb.
> >
> > Signed-off-by: Xudong Chen <[email protected]>
> > Signed-off-by: Liguo Zhang <[email protected]>
> > Signed-off-by: Eddie Huang <[email protected]>
> > ---
> > drivers/i2c/busses/i2c-mt65xx.c | 106 +++++++++++++++++++++++++++++-----------
> > 1 file changed, 77 insertions(+), 29 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
> > index 2ecf0d1..c501421 100644
> > --- a/drivers/i2c/busses/i2c-mt65xx.c
> > +++ b/drivers/i2c/busses/i2c-mt65xx.c
> [...]
>
> > static const struct of_device_id mtk_i2c_of_match[] = {
> > { .compatible = "mediatek,mt6577-i2c", .data = (void *)&mt6577_compat },
> > { .compatible = "mediatek,mt6589-i2c", .data = (void *)&mt6589_compat },
> > + { .compatible = "mediatek,mt8173-i2c", .data = (void *)&mt8173_compat },
> > {}
> > };
> > -MODULE_DEVICE_TABLE(of, mtk_i2c_match);
> > +MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);
>
> This should go into the previous patch, as 2/3 will probably not compile
> without this change.
>
That's right, my mistake, should be in 2/3.

Eddie


2015-04-28 10:02:15

by Lee Jones

[permalink] [raw]
Subject: Re: [PATCH v6 0/3] ARM: mediatek: Add driver for Mediatek I2C

On Tue, 28 Apr 2015, Eddie Huang wrote:

> This series is for Mediatek SoCs I2C controller common bus driver.
>
> Earlier MTK SoC ((for example, MT6589, MT8135)) I2C HW has some limitationes.
> New generation SoC like MT8173 fix following limitations:
>
> 1. Only support one i2c_msg number. One exception is WRRD (write then read)
> mode. WRRD can have two i2c_msg numbers.
>
> 2. Mediatek I2C controller support WRRD(write then read) mode, in WRRD
> mode the Repeat Start will be issued between 2 messages.
> In this driver if 2 messages is first write then read, the driver will
> combine 2 messages using Write-Read mode so the RS will be issued between
> the 2 messages.
>
> 3. The max transfer data length is 255 in one message. In WRRD mode, the
> max data length of second msg is 31.
>
> MT8135 and MT6589 can control I2C pins on PMIC(MT6397) by setting the i2c
> registers in MT8135 side. In this case, driver should set OFFSET_PATH_DIR
> bit first, the operation on other registers are still the same.
> For now MT6589/MT8135 support this, MT6577/MT6595/MT8127 do not support.
> For example, If want to use I2C4/5/6 pins on MT8135 just need to enable
> the pinmux, else if want to use I2C pins on PMIC(MT6397) need to add
> "mediatek,have-pmic" property in the .dts file of each platform.
>
> This driver is based on 4.1-rc1.
>
> Change in v6:
> 1. Update binding document not use default clock-frequency as example.
> 2. Add mtk_i2c_compatible struct and pass hardware capabilities
> through of_device_id
> 3. Remove some hardware setting in mtk_i2c_do_transfer to mtk_i2c_init_hw
> so just init one time.
> 4. Correct mtk_i2c_parse_dt don't set default clock bug.
>
> Change in v5:
> Apply new i2c_adapter_quirks patch [2]. Change to use dam_map_single to map
> dma buffer. Add spinlock to fix race condition. Check of_property_read_u32
> return value. Remove I2C_FUNC_10BIT_ADDR capability due to driver not implement.
> Add MT8173 I2C driver.
>
> Change in v4:
> Modify to support i2c_adapter_quirks base on Wolfram's patch [1].
> Remove check transfer size and WRRD combine code. Instead, fill quirk
> property and let i2c_check_for_quirks to do the filter.
>
> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/314804.html
> [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/325744.html
>
> Eddie Huang (1):
> I2C: mediatek: Add driver for MediaTek MT8173 I2C controller
>
> Xudong Chen (2):
> dt-bindings: Add I2C bindings for mt65xx/mt81xx.
> I2C: mediatek: Add driver for MediaTek I2C controller
>
> .../devicetree/bindings/i2c/i2c-mt6577.txt | 41 ++
> drivers/i2c/busses/Kconfig | 9 +
> drivers/i2c/busses/Makefile | 1 +
> drivers/i2c/busses/i2c-mt65xx.c | 748 +++++++++++++++++++++
> 4 files changed, 799 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
> create mode 100644 drivers/i2c/busses/i2c-mt65xx.c

Why have you sent me this?

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

2015-04-28 10:08:22

by Jean Delvare

[permalink] [raw]
Subject: Re: [PATCH v6 0/3] ARM: mediatek: Add driver for Mediatek I2C

Hi Lee, Eddie,

Le Tuesday 28 April 2015 à 11:02 +0100, Lee Jones a écrit :
> On Tue, 28 Apr 2015, Eddie Huang wrote:
>
> > This series is for Mediatek SoCs I2C controller common bus driver.
> >
> > Earlier MTK SoC ((for example, MT6589, MT8135)) I2C HW has some limitationes.
> > New generation SoC like MT8173 fix following limitations:
> >
> > 1. Only support one i2c_msg number. One exception is WRRD (write then read)
> > mode. WRRD can have two i2c_msg numbers.
> >
> > 2. Mediatek I2C controller support WRRD(write then read) mode, in WRRD
> > mode the Repeat Start will be issued between 2 messages.
> > In this driver if 2 messages is first write then read, the driver will
> > combine 2 messages using Write-Read mode so the RS will be issued between
> > the 2 messages.
> >
> > 3. The max transfer data length is 255 in one message. In WRRD mode, the
> > max data length of second msg is 31.
> >
> > MT8135 and MT6589 can control I2C pins on PMIC(MT6397) by setting the i2c
> > registers in MT8135 side. In this case, driver should set OFFSET_PATH_DIR
> > bit first, the operation on other registers are still the same.
> > For now MT6589/MT8135 support this, MT6577/MT6595/MT8127 do not support.
> > For example, If want to use I2C4/5/6 pins on MT8135 just need to enable
> > the pinmux, else if want to use I2C pins on PMIC(MT6397) need to add
> > "mediatek,have-pmic" property in the .dts file of each platform.
> >
> > This driver is based on 4.1-rc1.
> >
> > Change in v6:
> > 1. Update binding document not use default clock-frequency as example.
> > 2. Add mtk_i2c_compatible struct and pass hardware capabilities
> > through of_device_id
> > 3. Remove some hardware setting in mtk_i2c_do_transfer to mtk_i2c_init_hw
> > so just init one time.
> > 4. Correct mtk_i2c_parse_dt don't set default clock bug.
> >
> > Change in v5:
> > Apply new i2c_adapter_quirks patch [2]. Change to use dam_map_single to map
> > dma buffer. Add spinlock to fix race condition. Check of_property_read_u32
> > return value. Remove I2C_FUNC_10BIT_ADDR capability due to driver not implement.
> > Add MT8173 I2C driver.
> >
> > Change in v4:
> > Modify to support i2c_adapter_quirks base on Wolfram's patch [1].
> > Remove check transfer size and WRRD combine code. Instead, fill quirk
> > property and let i2c_check_for_quirks to do the filter.
> >
> > [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/314804.html
> > [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/325744.html
> >
> > Eddie Huang (1):
> > I2C: mediatek: Add driver for MediaTek MT8173 I2C controller
> >
> > Xudong Chen (2):
> > dt-bindings: Add I2C bindings for mt65xx/mt81xx.
> > I2C: mediatek: Add driver for MediaTek I2C controller
> >
> > .../devicetree/bindings/i2c/i2c-mt6577.txt | 41 ++
> > drivers/i2c/busses/Kconfig | 9 +
> > drivers/i2c/busses/Makefile | 1 +
> > drivers/i2c/busses/i2c-mt65xx.c | 748 +++++++++++++++++++++
> > 4 files changed, 799 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
> > create mode 100644 drivers/i2c/busses/i2c-mt65xx.c
>
> Why have you sent me this?

Mind you, I was wondering exactly the same ;-)


--
Jean Delvare
SUSE L3 Support

2015-04-29 05:18:30

by rajeev kumar

[permalink] [raw]
Subject: Re: [PATCH v6 1/3] dt-bindings: Add I2C bindings for mt65xx/mt81xx.

On Tue, Apr 28, 2015 at 2:01 PM, Eddie Huang <[email protected]> wrote:
> From: Xudong Chen <[email protected]>
>
> Add devicetree bindings for Mediatek Soc I2C driver.
>
> Signed-off-by: Xudong Chen <[email protected]>
> Signed-off-by: Eddie Huang <[email protected]>
> ---
> .../devicetree/bindings/i2c/i2c-mt6577.txt | 41 ++++++++++++++++++++++
> 1 file changed, 41 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
> new file mode 100644
> index 0000000..0ce6fa3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mt6577.txt
> @@ -0,0 +1,41 @@
> +* Mediatek's I2C controller
> +
> +The Mediatek's I2C controller is used to interface with I2C devices.
> +
> +Required properties:
> + - compatible: value should be either of the following.
> + (a) "mediatek,mt6577-i2c", for i2c compatible with mt6577 i2c.
> + (b) "mediatek,mt6589-i2c", for i2c compatible with mt6589 i2c.
> + (c) "mediatek,mt8127-i2c", for i2c compatible with mt8127 i2c.
> + (d) "mediatek,mt8135-i2c", for i2c compatible with mt8135 i2c.
> + (e) "mediatek,mt8173-i2c", for i2c compatible with mt8173 i2c.
> + - reg: physical base address of the controller and dma base, length of memory
> + mapped region.
> + - interrupts: interrupt number to the cpu.
> + - clock-div: the fixed value for frequency divider of clock source in i2c
> + module. Each IC may be different.
> + - clocks: clock name from clock manager
> + - clock-names: Must include "main" and "dma", if enable have-pmic need include
> + "pmic" extra.
> +
> +Optional properties:
> + - clock-frequency: Frequency in Hz of the bus when transfer, the default value
> + is 100000.

100000 HZ ...

> + - mediatek,have-pmic: platform can control i2c form special pmic side.
> + Only mt6589 and mt8135 support this feature.
> + - mediatek,use-push-pull: IO config use push-pull mode.
> +
> +Example:
> +
> + i2c0: i2c@1100d000 {
> + compatible = "mediatek,mt6577-i2c";
> + reg = <0x1100d000 0x70>,
> + <0x11000300 0x80>;
> + interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_LOW>;
> + clock-frequency = <400000>;
> + mediatek,have-pmic;
> + clock-div = <16>;
> + clocks = <&i2c0_ck>, <&ap_dma_ck>;
> + clock-names = "main", "dma";
> + };
> +
> --
> 1.8.1.1.dirty
>
> --
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