diff mbox

[1/4] gpio: davinci: Use devm_gpiochip_add_data in place of gpiochip_add_data

Message ID 1500375436-9435-2-git-send-email-j-keerthy@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

J, KEERTHY July 18, 2017, 10:57 a.m. UTC
Use the devm version of gpiochip_add_data and pass on the
return value. Reset the static variables to 0 before returning.

Signed-off-by: Keerthy <j-keerthy@ti.com>
---
 drivers/gpio/gpio-davinci.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Comments

Suman Anna July 18, 2017, 4:50 p.m. UTC | #1
Hi Keerthy,

On 07/18/2017 05:57 AM, Keerthy wrote:
> Use the devm version of gpiochip_add_data and pass on the
> return value. Reset the static variables to 0 before returning.
> 
> Signed-off-by: Keerthy <j-keerthy@ti.com>
> ---
>  drivers/gpio/gpio-davinci.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-davinci.c b/drivers/gpio/gpio-davinci.c
> index 65cb359..2c88054 100644
> --- a/drivers/gpio/gpio-davinci.c
> +++ b/drivers/gpio/gpio-davinci.c
> @@ -166,7 +166,7 @@ static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
>  static int davinci_gpio_probe(struct platform_device *pdev)
>  {
>  	static int ctrl_num, bank_base;
> -	int gpio, bank;
> +	int gpio, bank, ret = 0;
>  	unsigned ngpio, nbank;
>  	struct davinci_gpio_controller *chips;
>  	struct davinci_gpio_platform_data *pdata;
> @@ -232,7 +232,13 @@ static int davinci_gpio_probe(struct platform_device *pdev)
>  	for (gpio = 0, bank = 0; gpio < ngpio; gpio += 32, bank++)
>  		chips->regs[bank] = gpio_base + offset_array[bank];
>  
> -	gpiochip_add_data(&chips->chip, chips);
> +	ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
> +	if (ret) {
> +		ctrl_num = 0;
> +		bank_base = 0;

Hmm, this doesn't look right to me. These variables are defined as
static, and you are resetting them unconditionally. This should be an
issue when you have multiple devices and one of them fails.

regards
Suman

> +		return ret;
> +	}
> +
>  	platform_set_drvdata(pdev, chips);
>  	davinci_gpio_irq_setup(pdev);
>  	return 0;
>
J, KEERTHY July 18, 2017, 5:45 p.m. UTC | #2
On Tuesday 18 July 2017 10:20 PM, Suman Anna wrote:
> Hi Keerthy,
> 
> On 07/18/2017 05:57 AM, Keerthy wrote:
>> Use the devm version of gpiochip_add_data and pass on the
>> return value. Reset the static variables to 0 before returning.
>>
>> Signed-off-by: Keerthy <j-keerthy@ti.com>
>> ---
>>  drivers/gpio/gpio-davinci.c | 10 ++++++++--
>>  1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpio/gpio-davinci.c b/drivers/gpio/gpio-davinci.c
>> index 65cb359..2c88054 100644
>> --- a/drivers/gpio/gpio-davinci.c
>> +++ b/drivers/gpio/gpio-davinci.c
>> @@ -166,7 +166,7 @@ static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
>>  static int davinci_gpio_probe(struct platform_device *pdev)
>>  {
>>  	static int ctrl_num, bank_base;
>> -	int gpio, bank;
>> +	int gpio, bank, ret = 0;
>>  	unsigned ngpio, nbank;
>>  	struct davinci_gpio_controller *chips;
>>  	struct davinci_gpio_platform_data *pdata;
>> @@ -232,7 +232,13 @@ static int davinci_gpio_probe(struct platform_device *pdev)
>>  	for (gpio = 0, bank = 0; gpio < ngpio; gpio += 32, bank++)
>>  		chips->regs[bank] = gpio_base + offset_array[bank];
>>  
>> -	gpiochip_add_data(&chips->chip, chips);
>> +	ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
>> +	if (ret) {
>> +		ctrl_num = 0;
>> +		bank_base = 0;
> 
> Hmm, this doesn't look right to me. These variables are defined as
> static, and you are resetting them unconditionally. This should be an
> issue when you have multiple devices and one of them fails.

Agreed. With multiple instances this can reset the successful count also.

Upon failure in any iteration, the following should take care of those
static variables:

/* Revert the static variable increments */
        ctrl_num--;
        bank_base -= ngpio;

Thanks for the quick review!

Reagrds,
Keerthy

> 
> regards
> Suman
> 
>> +		return ret;
>> +	}
>> +
>>  	platform_set_drvdata(pdev, chips);
>>  	davinci_gpio_irq_setup(pdev);
>>  	return 0;
>>
>
Johan Hovold July 19, 2017, 9:37 a.m. UTC | #3
On Tue, Jul 18, 2017 at 04:27:13PM +0530, Keerthy wrote:
> Use the devm version of gpiochip_add_data and pass on the
> return value. Reset the static variables to 0 before returning.

You need to describe not just what you do, but also why you it. In this
case, your fixing memory leaks and the gpio chip being left registered
if this driver is unbound.

Johan
J, KEERTHY July 19, 2017, 9:58 a.m. UTC | #4
On Wednesday 19 July 2017 03:07 PM, Johan Hovold wrote:
> On Tue, Jul 18, 2017 at 04:27:13PM +0530, Keerthy wrote:
>> Use the devm version of gpiochip_add_data and pass on the
>> return value. Reset the static variables to 0 before returning.
> 
> You need to describe not just what you do, but also why you it. In this
> case, your fixing memory leaks and the gpio chip being left registered
> if this driver is unbound.

Sure i can add more description as mentioned above.

> 
> Johan
>
diff mbox

Patch

diff --git a/drivers/gpio/gpio-davinci.c b/drivers/gpio/gpio-davinci.c
index 65cb359..2c88054 100644
--- a/drivers/gpio/gpio-davinci.c
+++ b/drivers/gpio/gpio-davinci.c
@@ -166,7 +166,7 @@  static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
 static int davinci_gpio_probe(struct platform_device *pdev)
 {
 	static int ctrl_num, bank_base;
-	int gpio, bank;
+	int gpio, bank, ret = 0;
 	unsigned ngpio, nbank;
 	struct davinci_gpio_controller *chips;
 	struct davinci_gpio_platform_data *pdata;
@@ -232,7 +232,13 @@  static int davinci_gpio_probe(struct platform_device *pdev)
 	for (gpio = 0, bank = 0; gpio < ngpio; gpio += 32, bank++)
 		chips->regs[bank] = gpio_base + offset_array[bank];
 
-	gpiochip_add_data(&chips->chip, chips);
+	ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
+	if (ret) {
+		ctrl_num = 0;
+		bank_base = 0;
+		return ret;
+	}
+
 	platform_set_drvdata(pdev, chips);
 	davinci_gpio_irq_setup(pdev);
 	return 0;