[PATCH v3] gpio: pisosr: Use devm_gpiochip_add_data() to simplify remove path

[PATCH v3] gpio: pisosr: Use devm_gpiochip_add_data() to simplify remove path

[Andrew Davis]

Use devm version of gpiochip add function to handle removal for us.

While here update copyright and module author.

Signed-off-by: Andrew Davis <afd@ti.com>
---

Changes from v2:
 - Rebase on v6.4-rc2

Changes from v1:
 - Use devm to cleanup mutex

 drivers/gpio/gpio-pisosr.c | 30 ++++++++++++++----------------
 1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/drivers/gpio/gpio-pisosr.c b/drivers/gpio/gpio-pisosr.c
index 67071bea08c2..4c9d138a7dc7 100644
--- a/drivers/gpio/gpio-pisosr.c
+++ b/drivers/gpio/gpio-pisosr.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
- *	Andrew F. Davis <afd@ti.com>
+ * Copyright (C) 2015-2023 Texas Instruments Incorporated - https://www.ti.com/
+ *	Andrew Davis <afd@ti.com>
  */
 
 #include <linux/bitmap.h>
@@ -116,6 +116,13 @@ static const struct gpio_chip template_chip = {
 	.can_sleep		= true,
 };
 
+static void pisosr_mutex_destroy(void *data)
+{
+	struct mutex *lock = data;
+
+	mutex_destroy(lock);
+}
+
 static int pisosr_gpio_probe(struct spi_device *spi)
 {
 	struct device *dev = &spi->dev;
@@ -126,8 +133,6 @@ static int pisosr_gpio_probe(struct spi_device *spi)
 	if (!gpio)
 		return -ENOMEM;
 
-	spi_set_drvdata(spi, gpio);
-
 	gpio->chip = template_chip;
 	gpio->chip.parent = dev;
 	of_property_read_u16(dev->of_node, "ngpios", &gpio->chip.ngpio);
@@ -145,8 +150,11 @@ static int pisosr_gpio_probe(struct spi_device *spi)
 				     "Unable to allocate load GPIO\n");
 
 	mutex_init(&gpio->lock);
+	ret = devm_add_action_or_reset(dev, pisosr_mutex_destroy, &gpio->lock);
+	if (ret)
+		return ret;
 
-	ret = gpiochip_add_data(&gpio->chip, gpio);
+	ret = devm_gpiochip_add_data(dev, &gpio->chip, gpio);
 	if (ret < 0) {
 		dev_err(dev, "Unable to register gpiochip\n");
 		return ret;
@@ -155,15 +163,6 @@ static int pisosr_gpio_probe(struct spi_device *spi)
 	return 0;
 }
 
-static void pisosr_gpio_remove(struct spi_device *spi)
-{
-	struct pisosr_gpio *gpio = spi_get_drvdata(spi);
-
-	gpiochip_remove(&gpio->chip);
-
-	mutex_destroy(&gpio->lock);
-}
-
 static const struct spi_device_id pisosr_gpio_id_table[] = {
 	{ "pisosr-gpio", },
 	{ /* sentinel */ }
@@ -182,11 +181,10 @@ static struct spi_driver pisosr_gpio_driver = {
 		.of_match_table = pisosr_gpio_of_match_table,
 	},
 	.probe = pisosr_gpio_probe,
-	.remove = pisosr_gpio_remove,
 	.id_table = pisosr_gpio_id_table,
 };
 module_spi_driver(pisosr_gpio_driver);
 
-MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_AUTHOR("Andrew Davis <afd@ti.com>");
 MODULE_DESCRIPTION("SPI Compatible PISO Shift Register GPIO Driver");
 MODULE_LICENSE("GPL v2");
-- 
2.39.2

Re: [PATCH v3] gpio: pisosr: Use devm_gpiochip_add_data() to simplify remove path

[andy.shevchenko]

Mon, May 15, 2023 at 12:43:21PM -0500, Andrew Davis kirjoitti:
> Use devm version of gpiochip add function to handle removal for us.
> 
> While here update copyright and module author.

...

> +static void pisosr_mutex_destroy(void *data)
> +{
> +	struct mutex *lock = data;
> +
> +	mutex_destroy(lock);
> +}

No need to cast void * explicitly.

static void pisosr_mutex_destroy(void *lock)
{
	mutex_destroy(lock);
}

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3] gpio: pisosr: Use devm_gpiochip_add_data() to simplify remove path

[Andrew Davis]

On 5/15/23 1:34 PM, andy.shevchenko@gmail.com wrote:
> Mon, May 15, 2023 at 12:43:21PM -0500, Andrew Davis kirjoitti:
>> Use devm version of gpiochip add function to handle removal for us.
>>
>> While here update copyright and module author.
> 
> ...
> 
>> +static void pisosr_mutex_destroy(void *data)
>> +{
>> +	struct mutex *lock = data;
>> +
>> +	mutex_destroy(lock);
>> +}
> 
> No need to cast void * explicitly.
> 

No need sure, but I really think it looks cleaner to be
explicit with the types here. If you feel strongly I
can change it though.

Andrew

> static void pisosr_mutex_destroy(void *lock)
> {
> 	mutex_destroy(lock);
> }
> 

Re: [PATCH v3] gpio: pisosr: Use devm_gpiochip_add_data() to simplify remove path

[Andy Shevchenko]

On Tue, May 16, 2023 at 6:24 PM Andrew Davis <afd@ti.com> wrote:
> On 5/15/23 1:34 PM, andy.shevchenko@gmail.com wrote:

...

> >> +static void pisosr_mutex_destroy(void *data)
> >> +{
> >> +    struct mutex *lock = data;
> >> +
> >> +    mutex_destroy(lock);
> >> +}
> >
> > No need to cast void * explicitly.
> >
>
> No need sure, but I really think it looks cleaner to be
> explicit with the types here.

The parameter is void * and since it's a simplest wrapper on another
function there is no value to have a clear type. It brings nothing in
my opinion.

> If you feel strongly I
> can change it though.

I would go with less LoCs.

> > static void pisosr_mutex_destroy(void *lock)
> > {
> >       mutex_destroy(lock);
> > }

-- 
With Best Regards,
Andy Shevchenko