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

From: zhouyanjie
Date: Sat Dec 14 2019 - 07:33:09 EST


Hi Paul,

On 2019å12æ14æ 05:21, Paul Cercueil wrote:
Hi Zhou,


Le jeu., dÃc. 12, 2019 at 23:50, 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>
---
drivers/i2c/busses/i2c-jz4780.c | 159 +++++++++++++++++++++++++++++-----------
1 file changed, 117 insertions(+), 42 deletions(-)

diff --git a/drivers/i2c/busses/i2c-jz4780.c b/drivers/i2c/busses/i2c-jz4780.c
index 25dcd73..3b21896 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 +135,32 @@ 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 {
+ int fifosize;
+ int tx_level;
+ int rx_level;
+};
+
struct jz4780_i2c {
void __iomem *iomem;
int irq;
struct clk *clk;
struct i2c_adapter adap;
+ enum ingenic_i2c_version version;
+ const struct ingenic_i2c_config *cdata;

/* lock to protect rbuf and wbuf between xfer_rd/wr and irq handler */
spinlock_t lock;
@@ -340,11 +359,18 @@ 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->version >= ID_X1000)
+ jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, hold_time);
+ else {
+ 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->version >= ID_X1000)
+ jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, 0);
+ else
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0);
}

return 0;
@@ -359,9 +385,11 @@ 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->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 +427,18 @@ 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)
{
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->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 +493,40 @@ 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->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;
@@ -496,24 +534,22 @@ 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)) {
+ while ((i2c_sta & JZ4780_I2C_STA_TFNF) && (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->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) {
- tmp = jz4780_i2c_readw(i2c,
- JZ4780_I2C_CTRL);
+ if ((!i2c->stop_hold) && (i2c->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_CTRL, tmp);
}

jz4780_i2c_trans_done(i2c);
@@ -567,20 +603,22 @@ 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->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 +664,16 @@ 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->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 +756,21 @@ static const struct i2c_algorithm jz4780_i2c_algorithm = {
.functionality = jz4780_i2c_functionality,
};

+static const struct ingenic_i2c_config jz4780_i2c_config = {
+ .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 = {
+ .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 = (void *) ID_JZ4780 },
+ { .compatible = "ingenic,x1000-i2c", .data = (void *) ID_X1000 },

I think in general you should pass pointers to your ingenic_i2c_config structures directly in .data here, and have a "version" field in your ingenic_i2c_config struct.


Sure, I will change it in v2.


{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, jz4780_i2c_of_matches);
@@ -729,11 +782,24 @@ static int jz4780_i2c_probe(struct platform_device *pdev)
unsigned short tmp;
struct resource *r;
struct jz4780_i2c *i2c;
+ const struct platform_device_id *id = platform_get_device_id(pdev);
+ const struct of_device_id *of_id = of_match_device(
+ jz4780_i2c_of_matches, &pdev->dev);

i2c = devm_kzalloc(&pdev->dev, sizeof(struct jz4780_i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;

+ if (of_id)
+ i2c->version = (enum ingenic_i2c_version)of_id->data;
+ else
+ i2c->version = (enum ingenic_i2c_version)id->driver_data;
+
+ if (i2c->version >= ID_X1000)
+ i2c->cdata = &x1000_i2c_config;
+ else
+ i2c->cdata = &jz4780_i2c_config;
+

Then you can replace all these lines with:
i2c->cdata = device_get_match_data(dev);

And your checks on i2c->version become checks on i2c->cdata->version.


OK, will change in v2.


i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &jz4780_i2c_algorithm;
i2c->adap.algo_data = i2c;
@@ -777,9 +843,11 @@ 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->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);

@@ -809,6 +877,12 @@ static int jz4780_i2c_remove(struct platform_device *pdev)
return 0;
}

+static const struct platform_device_id ingenic_i2c_ids[] = {
+ { "jz4780-i2c", ID_JZ4780 },
+ { "x1000-i2c", ID_X1000 },
+ {},

I honestly think you can drop the platform ID table. It will never be used.


OK, just need to drop the platform ID table? Or any other changes need to be made?

Thanks and best regards!

Cheers,
-Paul

+};
+
static struct platform_driver jz4780_i2c_driver = {
.probe = jz4780_i2c_probe,
.remove = jz4780_i2c_remove,
@@ -816,6 +890,7 @@ static struct platform_driver jz4780_i2c_driver = {
.name = "jz4780-i2c",
.of_match_table = of_match_ptr(jz4780_i2c_of_matches),
},
+ .id_table = ingenic_i2c_ids,
};

module_platform_driver(jz4780_i2c_driver);
--
2.7.4