[PATCH 0/2] Match data improvements for mcp23s08 driver

[PATCH 0/2] Match data improvements for mcp23s08 driver

[Biju Das]

This patch series aims to add match data improvements for mcp23s08 driver.

This patch series is only compile tested.

Biju Das (2):
  pinctrl: mcp23s08: Extend match support for OF tables
  pinctrl: mcp23s08: Simplify probe()

 drivers/pinctrl/pinctrl-mcp23s08_i2c.c | 102 ++++++++++++-------------
 1 file changed, 50 insertions(+), 52 deletions(-)

-- 
2.25.1

[PATCH 1/2] pinctrl: mcp23s08: Extend match support for OF tables

[Biju Das]

The driver has OF match table, still it uses ID lookup table for
retrieving match data. Currently the driver is working on the
assumption that a I2C device registered via OF will always match a
legacy I2C device ID. The correct approach is to have an OF device ID
table using of_device_match_data() if the devices are registered via OF.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
 drivers/pinctrl/pinctrl-mcp23s08_i2c.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-mcp23s08_i2c.c b/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
index 3dd1bd8e73eb..393d9b099cc5 100644
--- a/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
+++ b/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
@@ -10,9 +10,8 @@
 
 static int mcp230xx_probe(struct i2c_client *client)
 {
-	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 	struct device *dev = &client->dev;
-	unsigned int type = id->driver_data;
+	unsigned int type;
 	struct mcp23s08 *mcp;
 	int ret;
 
@@ -20,6 +19,7 @@ static int mcp230xx_probe(struct i2c_client *client)
 	if (!mcp)
 		return -ENOMEM;
 
+	type = (uintptr_t)i2c_get_match_data(client);
 	switch (type) {
 	case MCP_TYPE_008:
 		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x08_regmap);
-- 
2.25.1

Re: [PATCH 1/2] pinctrl: mcp23s08: Extend match support for OF tables

[Andy Shevchenko]

On Sat, Sep 02, 2023 at 10:09:36AM +0100, Biju Das wrote:
> The driver has OF match table, still it uses ID lookup table for
> retrieving match data. Currently the driver is working on the
> assumption that a I2C device registered via OF will always match a
> legacy I2C device ID. The correct approach is to have an OF device ID
> table using of_device_match_data() if the devices are registered via OF.

...

> -	const struct i2c_device_id *id = i2c_client_get_device_id(client);
>  	struct device *dev = &client->dev;
> -	unsigned int type = id->driver_data;

> +	unsigned int type;


Now it's shorter than below line, so move it further.

>  	struct mcp23s08 *mcp;
>  	int ret;

-- 
With Best Regards,
Andy Shevchenko

[PATCH 2/2] pinctrl: mcp23s08: Simplify probe()

[Biju Das]

Add struct mcp23s08_i2c_info and simplify probe() by replacing
match data 'type' with 'struct mcp23s08_i2c_info'.

While at it, replace dev_err()->dev_err_probe().

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
 drivers/pinctrl/pinctrl-mcp23s08_i2c.c | 102 ++++++++++++-------------
 1 file changed, 50 insertions(+), 52 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-mcp23s08_i2c.c b/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
index 393d9b099cc5..61e92f68ec95 100644
--- a/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
+++ b/drivers/pinctrl/pinctrl-mcp23s08_i2c.c
@@ -8,10 +8,18 @@
 
 #include "pinctrl-mcp23s08.h"
 
+struct mcp23s08_i2c_info {
+	const struct regmap_config *regmap;
+	const char *label;
+	unsigned int type;
+	u16 ngpio;
+	bool reg_shift;
+};
+
 static int mcp230xx_probe(struct i2c_client *client)
 {
+	const struct mcp23s08_i2c_info *info;
 	struct device *dev = &client->dev;
-	unsigned int type;
 	struct mcp23s08 *mcp;
 	int ret;
 
@@ -19,41 +27,22 @@ static int mcp230xx_probe(struct i2c_client *client)
 	if (!mcp)
 		return -ENOMEM;
 
-	type = (uintptr_t)i2c_get_match_data(client);
-	switch (type) {
-	case MCP_TYPE_008:
-		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x08_regmap);
-		mcp->reg_shift = 0;
-		mcp->chip.ngpio = 8;
-		mcp->chip.label = "mcp23008";
-		break;
-
-	case MCP_TYPE_017:
-		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x17_regmap);
-		mcp->reg_shift = 1;
-		mcp->chip.ngpio = 16;
-		mcp->chip.label = "mcp23017";
-		break;
-
-	case MCP_TYPE_018:
-		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x17_regmap);
-		mcp->reg_shift = 1;
-		mcp->chip.ngpio = 16;
-		mcp->chip.label = "mcp23018";
-		break;
-
-	default:
-		dev_err(dev, "invalid device type (%d)\n", type);
-		return -EINVAL;
-	}
+	info = i2c_get_match_data(client);
+	if (!info)
+		return dev_err_probe(dev, -EINVAL, "invalid device type (%d)\n",
+				     info->type);
 
+	mcp->reg_shift = info->reg_shift;
+	mcp->chip.ngpio = info->ngpio;
+	mcp->chip.label = info->label;
+	mcp->regmap = devm_regmap_init_i2c(client, info->regmap);
 	if (IS_ERR(mcp->regmap))
 		return PTR_ERR(mcp->regmap);
 
 	mcp->irq = client->irq;
 	mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
 
-	ret = mcp23s08_probe_one(mcp, dev, client->addr, type, -1);
+	ret = mcp23s08_probe_one(mcp, dev, client->addr, info->type, -1);
 	if (ret)
 		return ret;
 
@@ -62,36 +51,45 @@ static int mcp230xx_probe(struct i2c_client *client)
 	return 0;
 }
 
+static const struct mcp23s08_i2c_info mcp23s08_i2c_0008 = {
+	.regmap = &mcp23x08_regmap,
+	.label = "mcp23008",
+	.type = MCP_TYPE_008,
+	.ngpio = 8,
+	.reg_shift = 0,
+};
+
+static const struct mcp23s08_i2c_info mcp23s08_i2c_0017 = {
+	.regmap = &mcp23x17_regmap,
+	.label = "mcp23017",
+	.type = MCP_TYPE_017,
+	.ngpio = 16,
+	.reg_shift = 1,
+};
+
+static const struct mcp23s08_i2c_info mcp23s08_i2c_0018 = {
+	.regmap = &mcp23x17_regmap,
+	.label = "mcp23018",
+	.type = MCP_TYPE_018,
+	.ngpio = 16,
+	.reg_shift = 1,
+};
+
 static const struct i2c_device_id mcp230xx_id[] = {
-	{ "mcp23008", MCP_TYPE_008 },
-	{ "mcp23017", MCP_TYPE_017 },
-	{ "mcp23018", MCP_TYPE_018 },
+	{ "mcp23008", (kernel_ulong_t)&mcp23s08_i2c_0008 },
+	{ "mcp23017", (kernel_ulong_t)&mcp23s08_i2c_0017 },
+	{ "mcp23018", (kernel_ulong_t)&mcp23s08_i2c_0018 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
 
 static const struct of_device_id mcp23s08_i2c_of_match[] = {
-	{
-		.compatible = "microchip,mcp23008",
-		.data = (void *) MCP_TYPE_008,
-	},
-	{
-		.compatible = "microchip,mcp23017",
-		.data = (void *) MCP_TYPE_017,
-	},
-	{
-		.compatible = "microchip,mcp23018",
-		.data = (void *) MCP_TYPE_018,
-	},
+	{ .compatible = "microchip,mcp23008", .data = &mcp23s08_i2c_0008 },
+	{ .compatible = "microchip,mcp23017", .data = &mcp23s08_i2c_0017 },
+	{ .compatible = "microchip,mcp23018", .data = &mcp23s08_i2c_0018 },
 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
-	{
-		.compatible = "mcp,mcp23008",
-		.data = (void *) MCP_TYPE_008,
-	},
-	{
-		.compatible = "mcp,mcp23017",
-		.data = (void *) MCP_TYPE_017,
-	},
+	{ .compatible = "mcp,mcp23008", .data = &mcp23s08_i2c_0008 },
+	{ .compatible = "mcp,mcp23017", .data = &mcp23s08_i2c_0017 },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
-- 
2.25.1

Re: [PATCH 2/2] pinctrl: mcp23s08: Simplify probe()

[Andy Shevchenko]

On Sat, Sep 02, 2023 at 10:09:37AM +0100, Biju Das wrote:
> Add struct mcp23s08_i2c_info and simplify probe() by replacing
> match data 'type' with 'struct mcp23s08_i2c_info'.
> 
> While at it, replace dev_err()->dev_err_probe().

'->' --> ' --> '

...

> +	info = i2c_get_match_data(client);
> +	if (!info)
> +		return dev_err_probe(dev, -EINVAL, "invalid device type (%d)\n",

> +				     info->type);

Huh?! Please, think about it...

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 2/2] pinctrl: mcp23s08: Simplify probe()

[Dan Carpenter]

Hi Biju,

kernel test robot noticed the following build warnings:

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Biju-Das/pinctrl-mcp23s08-Extend-match-support-for-OF-tables/20230902-171023
base:   https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git devel
patch link:    https://lore.kernel.org/r/20230902090937.32195-3-biju.das.jz%40bp.renesas.com
patch subject: [PATCH 2/2] pinctrl: mcp23s08: Simplify probe()
config: i386-randconfig-141-20230902 (https://download.01.org/0day-ci/archive/20230903/202309030751.GQvtrZnS-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230903/202309030751.GQvtrZnS-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202309030751.GQvtrZnS-lkp@intel.com/

smatch warnings:
drivers/pinctrl/pinctrl-mcp23s08_i2c.c:33 mcp230xx_probe() error: we previously assumed 'info' could be null (see line 31)

vim +/info +33 drivers/pinctrl/pinctrl-mcp23s08_i2c.c

8bb5811129f9e4 Uwe Kleine-König 2022-11-18  19  static int mcp230xx_probe(struct i2c_client *client)
0f04a81784fe3d Andy Shevchenko  2020-04-07  20  {
b5f259f6fc5912 Biju Das         2023-09-02  21  	const struct mcp23s08_i2c_info *info;
0f04a81784fe3d Andy Shevchenko  2020-04-07  22  	struct device *dev = &client->dev;
0f04a81784fe3d Andy Shevchenko  2020-04-07  23  	struct mcp23s08 *mcp;
0f04a81784fe3d Andy Shevchenko  2020-04-07  24  	int ret;
0f04a81784fe3d Andy Shevchenko  2020-04-07  25  
0f04a81784fe3d Andy Shevchenko  2020-04-07  26  	mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
0f04a81784fe3d Andy Shevchenko  2020-04-07  27  	if (!mcp)
0f04a81784fe3d Andy Shevchenko  2020-04-07  28  		return -ENOMEM;
0f04a81784fe3d Andy Shevchenko  2020-04-07  29  
b5f259f6fc5912 Biju Das         2023-09-02  30  	info = i2c_get_match_data(client);
b5f259f6fc5912 Biju Das         2023-09-02 @31  	if (!info)
b5f259f6fc5912 Biju Das         2023-09-02  32  		return dev_err_probe(dev, -EINVAL, "invalid device type (%d)\n",
b5f259f6fc5912 Biju Das         2023-09-02 @33  				     info->type);
                                                                                     ^^^^^^^^^^
info is NULL.

0f04a81784fe3d Andy Shevchenko  2020-04-07  34  
b5f259f6fc5912 Biju Das         2023-09-02  35  	mcp->reg_shift = info->reg_shift;

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 0/2] Match data improvements for mcp23s08 driver

[Andy Shevchenko]

On Sat, Sep 02, 2023 at 10:09:35AM +0100, Biju Das wrote:
> This patch series aims to add match data improvements for mcp23s08 driver.
> 
> This patch series is only compile tested.

When driver has SPI and I2C parts, always take into account both of them.
There is more work needed here.

-- 
With Best Regards,
Andy Shevchenko