Convert enum->pointer for data in the match tables, so that
device_get_match_data() can do match against OF/ACPI/I2C tables, once i2c
bus type match support added to it.

Replace enum->struct *pca955x_chipdefs for data in the match table.
Simplify the probe() by replacing device_get_match_data() and ID lookup
for retrieving data by i2c_get_match_data().

While at it, add const definition to pca955x_chipdefs[].

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lee Jones <lee@kernel.org>
---
v1->v2:
 * Rebased to leds-next.
 * Added Rb tag from Lee Jones.
---
 drivers/leds/leds-pca955x.c | 49 ++++++++++++++-----------------------
 1 file changed, 18 insertions(+), 31 deletions(-)

diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c
index 1d7fa0cd97bf..891cfc05301d 100644
--- a/drivers/leds/leds-pca955x.c
+++ b/drivers/leds/leds-pca955x.c
@@ -76,7 +76,7 @@ struct pca955x_chipdef {
 	int			slv_addr_shift;	/* Number of bits to ignore */
 };
 
-static struct pca955x_chipdef pca955x_chipdefs[] = {
+static const struct pca955x_chipdef pca955x_chipdefs[] = {
 	[pca9550] = {
 		.bits		= 2,
 		.slv_addr	= /* 110000x */ 0x60,
@@ -105,11 +105,11 @@ static struct pca955x_chipdef pca955x_chipdefs[] = {
 };
 
 static const struct i2c_device_id pca955x_id[] = {
-	{ "pca9550", pca9550 },
-	{ "pca9551", pca9551 },
-	{ "pca9552", pca9552 },
-	{ "ibm-pca9552", ibm_pca9552 },
-	{ "pca9553", pca9553 },
+	{ "pca9550", (kernel_ulong_t)&pca955x_chipdefs[pca9550] },
+	{ "pca9551", (kernel_ulong_t)&pca955x_chipdefs[pca9551] },
+	{ "pca9552", (kernel_ulong_t)&pca955x_chipdefs[pca9552] },
+	{ "ibm-pca9552", (kernel_ulong_t)&pca955x_chipdefs[ibm_pca9552] },
+	{ "pca9553", (kernel_ulong_t)&pca955x_chipdefs[pca9553] },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, pca955x_id);
@@ -117,7 +117,7 @@ MODULE_DEVICE_TABLE(i2c, pca955x_id);
 struct pca955x {
 	struct mutex lock;
 	struct pca955x_led *leds;
-	struct pca955x_chipdef	*chipdef;
+	const struct pca955x_chipdef	*chipdef;
 	struct i2c_client	*client;
 	unsigned long active_pins;
 #ifdef CONFIG_LEDS_PCA955X_GPIO
@@ -415,7 +415,7 @@ static int pca955x_gpio_direction_output(struct gpio_chip *gc,
 #endif /* CONFIG_LEDS_PCA955X_GPIO */
 
 static struct pca955x_platform_data *
-pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
+pca955x_get_pdata(struct i2c_client *client, const struct pca955x_chipdef *chip)
 {
 	struct pca955x_platform_data *pdata;
 	struct pca955x_led *led;
@@ -458,11 +458,11 @@ pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
 }
 
 static const struct of_device_id of_pca955x_match[] = {
-	{ .compatible = "nxp,pca9550", .data = (void *)pca9550 },
-	{ .compatible = "nxp,pca9551", .data = (void *)pca9551 },
-	{ .compatible = "nxp,pca9552", .data = (void *)pca9552 },
-	{ .compatible = "ibm,pca9552", .data = (void *)ibm_pca9552 },
-	{ .compatible = "nxp,pca9553", .data = (void *)pca9553 },
+	{ .compatible = "nxp,pca9550", .data = &pca955x_chipdefs[pca9550] },
+	{ .compatible = "nxp,pca9551", .data = &pca955x_chipdefs[pca9551] },
+	{ .compatible = "nxp,pca9552", .data = &pca955x_chipdefs[pca9552] },
+	{ .compatible = "ibm,pca9552", .data = &pca955x_chipdefs[ibm_pca9552] },
+	{ .compatible = "nxp,pca9553", .data = &pca955x_chipdefs[pca9553] },
 	{},
 };
 MODULE_DEVICE_TABLE(of, of_pca955x_match);
@@ -471,7 +471,7 @@ static int pca955x_probe(struct i2c_client *client)
 {
 	struct pca955x *pca955x;
 	struct pca955x_led *pca955x_led;
-	struct pca955x_chipdef *chip;
+	const struct pca955x_chipdef *chip;
 	struct led_classdev *led;
 	struct led_init_data init_data;
 	struct i2c_adapter *adapter;
@@ -480,24 +480,11 @@ static int pca955x_probe(struct i2c_client *client)
 	bool set_default_label = false;
 	bool keep_pwm = false;
 	char default_label[8];
-	enum pca955x_type chip_type;
-	const void *md = device_get_match_data(&client->dev);
-
-	if (md) {
-		chip_type = (enum pca955x_type)(uintptr_t)md;
-	} else {
-		const struct i2c_device_id *id = i2c_match_id(pca955x_id,
-							      client);
-
-		if (id) {
-			chip_type = (enum pca955x_type)id->driver_data;
-		} else {
-			dev_err(&client->dev, "unknown chip\n");
-			return -ENODEV;
-		}
-	}
 
-	chip = &pca955x_chipdefs[chip_type];
+	chip = i2c_get_match_data(client);
+	if (!chip)
+		return dev_err_probe(&client->dev, -ENODEV, "unknown chip\n");
+
 	adapter = client->adapter;
 	pdata = dev_get_platdata(&client->dev);
 	if (!pdata) {
-- 
2.25.1

On Sat, Sep 23, 2023 at 06:19:20PM +0100, Biju Das wrote:
> Convert enum->pointer for data in the match tables, so that
> device_get_match_data() can do match against OF/ACPI/I2C tables, once i2c
> bus type match support added to it.
> 
> Replace enum->struct *pca955x_chipdefs for data in the match table.
> Simplify the probe() by replacing device_get_match_data() and ID lookup
> for retrieving data by i2c_get_match_data().
> 
> While at it, add const definition to pca955x_chipdefs[].

...

> -	struct pca955x_chipdef	*chipdef;
> +	const struct pca955x_chipdef	*chipdef;

No need to preserve TAB(s) here.

Otherwise looks good to me,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

On Mon, 25 Sep 2023, Andy Shevchenko wrote:

> On Sat, Sep 23, 2023 at 06:19:20PM +0100, Biju Das wrote:
> > Convert enum->pointer for data in the match tables, so that
> > device_get_match_data() can do match against OF/ACPI/I2C tables, once i2c
> > bus type match support added to it.
> > 
> > Replace enum->struct *pca955x_chipdefs for data in the match table.
> > Simplify the probe() by replacing device_get_match_data() and ID lookup
> > for retrieving data by i2c_get_match_data().
> > 
> > While at it, add const definition to pca955x_chipdefs[].
> 
> ...
> 
> > -	struct pca955x_chipdef	*chipdef;
> > +	const struct pca955x_chipdef	*chipdef;
> 
> No need to preserve TAB(s) here.

Follow-up please.

-- 
Lee Jones [李琼斯]

Hi Lee Jones,

> -----Original Message-----
> From: Lee Jones <lee@kernel.org>
> Sent: Thursday, September 28, 2023 2:44 PM
> To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Cc: Biju Das <biju.das.jz@bp.renesas.com>; Pavel Machek <pavel@ucw.cz>;
> linux-leds@vger.kernel.org; linux-kernel@vger.kernel.org; Biju Das
> <biju.das.au@gmail.com>
> Subject: Re: [PATCH v2 1/2] leds: pca955x: Convert enum->pointer for data
> in the match tables
> 
> On Mon, 25 Sep 2023, Andy Shevchenko wrote:
> 
> > On Sat, Sep 23, 2023 at 06:19:20PM +0100, Biju Das wrote:
> > > Convert enum->pointer for data in the match tables, so that
> > > device_get_match_data() can do match against OF/ACPI/I2C tables,
> > > once i2c bus type match support added to it.
> > >
> > > Replace enum->struct *pca955x_chipdefs for data in the match table.
> > > Simplify the probe() by replacing device_get_match_data() and ID
> > > lookup for retrieving data by i2c_get_match_data().
> > >
> > > While at it, add const definition to pca955x_chipdefs[].
> >
> > ...
> >
> > > -	struct pca955x_chipdef	*chipdef;
> > > +	const struct pca955x_chipdef	*chipdef;
> >
> > No need to preserve TAB(s) here.
> 
> Follow-up please.

Sure will send a follow-up patch to fix this tab issue as it is a separate change.

Cheers,
Biju