openwrt/target/linux/mediatek/patches/0031-I2C-mediatek-Add-driver-for-MediaTek-MT8173-I2C-cont.patch
John Crispin 25afe99b31 mediatek: add support for the new MT7623 Arm SoC
the support is still WIP. next steps are to make the pmic and ethernet work.
this is the first commit to make sure nothing gets lost.

Signed-off-by: John Crispin <blogic@openwrt.org>

SVN-Revision: 47354
2015-11-02 10:18:50 +00:00

245 lines
7.5 KiB
Diff

From 5f33206ebe4fb4a2cc8634f29c3e3c9bc01e3416 Mon Sep 17 00:00:00 2001
From: Eddie Huang <eddie.huang@mediatek.com>
Date: Wed, 6 May 2015 16:37:07 +0800
Subject: [PATCH 31/76] 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 <xudong.chen@mediatek.com>
Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com>
Signed-off-by: Eddie Huang <eddie.huang@mediatek.com>
---
drivers/i2c/busses/i2c-mt65xx.c | 104 ++++++++++++++++++++++++++++-----------
1 file changed, 76 insertions(+), 28 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index faecf7e..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 {
@@ -172,21 +179,39 @@ 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_of_match);
@@ -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);
--
1.7.10.4