Re: [PATCH v2 2/2] I2C: JZ4780: Add support for the X1000.

From: Paul Cercueil
Date: Mon Dec 16 2019 - 08:57:15 EST


Hi Zhou,


Le lun., dÃc. 16, 2019 at 18:06, åçæ (Zhou Yanjie) <zhouyanjie@xxxxxxxxxxxxxx> a Ãcrit :
Add support for probing i2c driver on the X1000 Soc from Ingenic.
call the corresponding fifo parameter according to the device
model obtained from the devicetree.

Signed-off-by: åçæ (Zhou Yanjie) <zhouyanjie@xxxxxxxxxxxxxx>
---

Notes:
v1->v2:
Add code to check device_get_match_data(), if it return a NULL ptr,
then print an error message and return -ENODEV.

drivers/i2c/busses/i2c-jz4780.c | 155 +++++++++++++++++++++++++++++-----------
1 file changed, 115 insertions(+), 40 deletions(-)

diff --git a/drivers/i2c/busses/i2c-jz4780.c b/drivers/i2c/busses/i2c-jz4780.c
index 25dcd73..f07a07c 100644
--- a/drivers/i2c/busses/i2c-jz4780.c
+++ b/drivers/i2c/busses/i2c-jz4780.c
@@ -4,6 +4,7 @@
*
* Copyright (C) 2006 - 2009 Ingenic Semiconductor Inc.
* Copyright (C) 2015 Imagination Technologies
+ * Copyright (C) 2019 åçæ (Zhou Yanjie) <zhouyanjie@xxxxxxxxxxxxxx>
*/

#include <linux/bitops.h>
@@ -17,6 +18,7 @@
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/slab.h>
@@ -55,6 +57,7 @@
#define JZ4780_I2C_ACKGC 0x98
#define JZ4780_I2C_ENSTA 0x9C
#define JZ4780_I2C_SDAHD 0xD0
+#define X1000_I2C_SDAHD 0x7C

#define JZ4780_I2C_CTRL_STPHLD BIT(7)
#define JZ4780_I2C_CTRL_SLVDIS BIT(6)
@@ -73,6 +76,8 @@
#define JZ4780_I2C_STA_TFNF BIT(1)
#define JZ4780_I2C_STA_ACT BIT(0)

+#define X1000_I2C_DC_STOP BIT(9)
+
static const char * const jz4780_i2c_abrt_src[] = {
"ABRT_7B_ADDR_NOACK",
"ABRT_10ADDR1_NOACK",
@@ -130,18 +135,33 @@ static const char * const jz4780_i2c_abrt_src[] = {
#define JZ4780_I2CFLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1))

#define JZ4780_I2C_FIFO_LEN 16
-#define TX_LEVEL 3
-#define RX_LEVEL (JZ4780_I2C_FIFO_LEN - TX_LEVEL - 1)
+
+#define X1000_I2C_FIFO_LEN 64

#define JZ4780_I2C_TIMEOUT 300

#define BUFSIZE 200

+enum ingenic_i2c_version {
+ ID_JZ4780,
+ ID_X1000,
+};
+
+/* ingenic_i2c_config: SoC specific config data. */
+struct ingenic_i2c_config {
+ enum ingenic_i2c_version version;
+
+ int fifosize;
+ int tx_level;
+ int rx_level;
+};
+
struct jz4780_i2c {
void __iomem *iomem;
int irq;
struct clk *clk;
struct i2c_adapter adap;
+ const struct ingenic_i2c_config *cdata;

/* lock to protect rbuf and wbuf between xfer_rd/wr and irq handler */
spinlock_t lock;
@@ -340,11 +360,18 @@ static int jz4780_i2c_set_speed(struct jz4780_i2c *i2c)

if (hold_time >= 0) {
/*i2c hold time enable */
- hold_time |= JZ4780_I2C_SDAHD_HDENB;
- jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, hold_time);
+ if (i2c->cdata->version >= ID_X1000)
+ jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, hold_time);
+ else {

If only one branch of a conditional statement is a single statement, then you should use braces in both branches.

See: https://www.kernel.org/doc/html/v4.10/process/coding-style.html#placing-braces-and-spaces


+ hold_time |= JZ4780_I2C_SDAHD_HDENB;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, hold_time);
+ }
} else {
/* disable hold time */
- jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0);
+ if (i2c->cdata->version >= ID_X1000)
+ jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, 0);
+ else
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0);
}

return 0;
@@ -359,9 +386,11 @@ static int jz4780_i2c_cleanup(struct jz4780_i2c *i2c)
spin_lock_irqsave(&i2c->lock, flags);

/* can send stop now if need */
- tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
- tmp &= ~JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ if (i2c->cdata->version < ID_X1000) {
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ }

/* disable all interrupts first */
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0);
@@ -399,11 +428,18 @@ static int jz4780_i2c_prepare(struct jz4780_i2c *i2c)
return jz4780_i2c_enable(i2c);
}

-static void jz4780_i2c_send_rcmd(struct jz4780_i2c *i2c, int cmd_count)
+static void jz4780_i2c_send_rcmd(struct jz4780_i2c *i2c,
+ int cmd_count, int cmd_left)

Sorry to be pedantic ;) but this line is not properly indented. You should indent with tab charaters (configure your IDE for one tab == 4 spaces) as much as possible, then use spaces to align the first word.

With these two things fixed:
Acked-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>

Cheers,
-Paul


{
int i;

- for (i = 0; i < cmd_count; i++)
+ for (i = 0; i < cmd_count - 1; i++)
+ jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ);
+
+ if ((cmd_left == 0) && (i2c->cdata->version >= ID_X1000))
+ jz4780_i2c_writew(i2c, JZ4780_I2C_DC,
+ JZ4780_I2C_DC_READ | X1000_I2C_DC_STOP);
+ else
jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ);
}

@@ -458,37 +494,44 @@ static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id)

rd_left = i2c->rd_total_len - i2c->rd_data_xfered;

- if (rd_left <= JZ4780_I2C_FIFO_LEN)
+ if (rd_left <= i2c->cdata->fifosize)
jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, rd_left - 1);
}

if (intst & JZ4780_I2C_INTST_TXEMP) {
if (i2c->is_write == 0) {
int cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
- int max_send = (JZ4780_I2C_FIFO_LEN - 1)
+ int max_send = (i2c->cdata->fifosize - 1)
- (i2c->rd_cmd_xfered
- i2c->rd_data_xfered);
int cmd_to_send = min(cmd_left, max_send);

if (i2c->rd_cmd_xfered != 0)
cmd_to_send = min(cmd_to_send,
- JZ4780_I2C_FIFO_LEN
- - TX_LEVEL - 1);
+ i2c->cdata->fifosize
+ - i2c->cdata->tx_level - 1);

if (cmd_to_send) {
- jz4780_i2c_send_rcmd(i2c, cmd_to_send);
i2c->rd_cmd_xfered += cmd_to_send;
+ cmd_left = i2c->rd_total_len -
+ i2c->rd_cmd_xfered;
+ jz4780_i2c_send_rcmd(i2c,
+ cmd_to_send, cmd_left);
+
}

- cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
if (cmd_left == 0) {
intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM);
intmsk &= ~JZ4780_I2C_INTM_MTXEMP;
jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, intmsk);

- tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
- tmp &= ~JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ if (i2c->cdata->version < ID_X1000) {
+ tmp = jz4780_i2c_readw(i2c,
+ JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c,
+ JZ4780_I2C_CTRL, tmp);
+ }
}
} else {
unsigned short data;
@@ -497,23 +540,26 @@ static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id)
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);

while ((i2c_sta & JZ4780_I2C_STA_TFNF) &&
- (i2c->wt_len > 0)) {
+ (i2c->wt_len > 0)) {
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
data = *i2c->wbuf;
data &= ~JZ4780_I2C_DC_READ;
- jz4780_i2c_writew(i2c, JZ4780_I2C_DC,
- data);
+ if ((!i2c->stop_hold) && (i2c->cdata->version >=
+ ID_X1000))
+ data |= X1000_I2C_DC_STOP;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_DC, data);
i2c->wbuf++;
i2c->wt_len--;
}

if (i2c->wt_len == 0) {
- if (!i2c->stop_hold) {
+ if ((!i2c->stop_hold) && (i2c->cdata->version <
+ ID_X1000)) {
tmp = jz4780_i2c_readw(i2c,
- JZ4780_I2C_CTRL);
+ JZ4780_I2C_CTRL);
tmp &= ~JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL,
- tmp);
+ jz4780_i2c_writew(i2c,
+ JZ4780_I2C_CTRL, tmp);
}

jz4780_i2c_trans_done(i2c);
@@ -567,20 +613,22 @@ static inline int jz4780_i2c_xfer_read(struct jz4780_i2c *i2c,
i2c->rd_data_xfered = 0;
i2c->rd_cmd_xfered = 0;

- if (len <= JZ4780_I2C_FIFO_LEN)
+ if (len <= i2c->cdata->fifosize)
jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, len - 1);
else
- jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, RX_LEVEL);
+ jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, i2c->cdata->rx_level);

- jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
+ jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, i2c->cdata->tx_level);

jz4780_i2c_writew(i2c, JZ4780_I2C_INTM,
JZ4780_I2C_INTM_MRXFL | JZ4780_I2C_INTM_MTXEMP
| JZ4780_I2C_INTM_MTXABT | JZ4780_I2C_INTM_MRXOF);

- tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
- tmp |= JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ if (i2c->cdata->version < ID_X1000) {
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp |= JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ }

spin_unlock_irqrestore(&i2c->lock, flags);

@@ -626,14 +674,16 @@ static inline int jz4780_i2c_xfer_write(struct jz4780_i2c *i2c,
i2c->wbuf = buf;
i2c->wt_len = len;

- jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
+ jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, i2c->cdata->tx_level);

jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, JZ4780_I2C_INTM_MTXEMP
| JZ4780_I2C_INTM_MTXABT);

- tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
- tmp |= JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ if (i2c->cdata->version < ID_X1000) {
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp |= JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ }

spin_unlock_irqrestore(&i2c->lock, flags);

@@ -716,8 +766,25 @@ static const struct i2c_algorithm jz4780_i2c_algorithm = {
.functionality = jz4780_i2c_functionality,
};

+static const struct ingenic_i2c_config jz4780_i2c_config = {
+ .version = ID_JZ4780,
+
+ .fifosize = JZ4780_I2C_FIFO_LEN,
+ .tx_level = JZ4780_I2C_FIFO_LEN / 2,
+ .rx_level = JZ4780_I2C_FIFO_LEN / 2 - 1,
+};
+
+static const struct ingenic_i2c_config x1000_i2c_config = {
+ .version = ID_X1000,
+
+ .fifosize = X1000_I2C_FIFO_LEN,
+ .tx_level = X1000_I2C_FIFO_LEN / 2,
+ .rx_level = X1000_I2C_FIFO_LEN / 2 - 1,
+};
+
static const struct of_device_id jz4780_i2c_of_matches[] = {
- { .compatible = "ingenic,jz4780-i2c", },
+ { .compatible = "ingenic,jz4780-i2c", .data = &jz4780_i2c_config },
+ { .compatible = "ingenic,x1000-i2c", .data = &x1000_i2c_config },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, jz4780_i2c_of_matches);
@@ -734,6 +801,12 @@ static int jz4780_i2c_probe(struct platform_device *pdev)
if (!i2c)
return -ENOMEM;

+ i2c->cdata = device_get_match_data(&pdev->dev);
+ if (!i2c->cdata) {
+ dev_err(&pdev->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &jz4780_i2c_algorithm;
i2c->adap.algo_data = i2c;
@@ -777,9 +850,11 @@ static int jz4780_i2c_probe(struct platform_device *pdev)

dev_info(&pdev->dev, "Bus frequency is %d KHz\n", i2c->speed);

- tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
- tmp &= ~JZ4780_I2C_CTRL_STPHLD;
- jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ if (i2c->cdata->version < ID_X1000) {
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ }

jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0x0);

--
2.7.4