[v1,2/4] hte: tegra194: don't access struct gpio_chip

Message ID 20231010151709.4104747-3-andriy.shevchenko@linux.intel.com
State New
Headers
Series hte: Improve GPIO handling and other cleanups |

Commit Message

Andy Shevchenko Oct. 10, 2023, 3:17 p.m. UTC
  From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Using struct gpio_chip is not safe as it will disappear if the
underlying driver is unbound for any reason. Switch to using reference
counted struct gpio_device and its dedicated accessors.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
[andy: used gpio_device_find_by_fwnode()]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/hte/hte-tegra194.c | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)
  

Comments

Dipen Patel Oct. 10, 2023, 4:19 p.m. UTC | #1
On 10/10/23 8:17 AM, Andy Shevchenko wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> Using struct gpio_chip is not safe as it will disappear if the
> underlying driver is unbound for any reason. Switch to using reference
> counted struct gpio_device and its dedicated accessors.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> Tested-by: Dipen Patel <dipenp@nvidia.com>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> [andy: used gpio_device_find_by_fwnode()]
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/hte/hte-tegra194.c | 33 +++++++++++++++++++--------------
>  1 file changed, 19 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/hte/hte-tegra194.c b/drivers/hte/hte-tegra194.c
> index 9fd3c00ff695..339ff5921ec8 100644
> --- a/drivers/hte/hte-tegra194.c
> +++ b/drivers/hte/hte-tegra194.c
> @@ -132,7 +132,7 @@ struct tegra_hte_soc {
>  	const struct tegra_hte_data *prov_data;
>  	struct tegra_hte_line_data *line_data;
>  	struct hte_chip *chip;
> -	struct gpio_chip *c;
> +	struct gpio_device *gdev;
>  	void __iomem *regs;
>  };
>  
> @@ -421,7 +421,7 @@ static int tegra_hte_line_xlate(struct hte_chip *gc,
>  	 * HTE/GTE namespace.
>  	 */
>  	if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && !args) {
> -		line_id = desc->attr.line_id - gs->c->base;
> +		line_id = desc->attr.line_id - gpio_device_get_base(gs->gdev);
>  		map = gs->prov_data->map;
>  		map_sz = gs->prov_data->map_sz;
>  	} else if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && args) {
> @@ -643,12 +643,15 @@ static irqreturn_t tegra_hte_isr(int irq, void *dev_id)
>  static bool tegra_hte_match_from_linedata(const struct hte_chip *chip,
>  					  const struct hte_ts_desc *hdesc)
>  {
> +	struct gpio_device *gdev __free(gpio_device_put) = NULL;
>  	struct tegra_hte_soc *hte_dev = chip->data;
>  
>  	if (!hte_dev || (hte_dev->prov_data->type != HTE_TEGRA_TYPE_GPIO))
>  		return false;
>  
> -	return hte_dev->c == gpiod_to_chip(hdesc->attr.line_data);
> +	gdev = gpiod_to_device(hdesc->attr.line_data);
> +
> +	return hte_dev->gdev == gdev;
>  }
>  
>  static const struct of_device_id tegra_hte_of_match[] = {
> @@ -676,14 +679,11 @@ static void tegra_gte_disable(void *data)
>  	tegra_hte_writel(gs, HTE_TECTRL, 0);
>  }
>  
> -static int tegra_get_gpiochip_from_name(struct gpio_chip *chip, void *data)
> +static void tegra_hte_put_gpio_device(void *data)
>  {
> -	return !strcmp(chip->label, data);
> -}
> +	struct gpio_device *gdev = data;
>  
> -static int tegra_gpiochip_match(struct gpio_chip *chip, void *data)
> -{
> -	return chip->fwnode == of_node_to_fwnode(data);
> +	gpio_device_put(gdev);
>  }
>  
>  static int tegra_hte_probe(struct platform_device *pdev)
> @@ -763,8 +763,8 @@ static int tegra_hte_probe(struct platform_device *pdev)
>  
>  		if (of_device_is_compatible(dev->of_node,
>  					    "nvidia,tegra194-gte-aon")) {
> -			hte_dev->c = gpiochip_find("tegra194-gpio-aon",
> -						tegra_get_gpiochip_from_name);
> +			hte_dev->gdev =
> +				gpio_device_find_by_label("tegra194-gpio-aon");
>  		} else {
>  			gpio_ctrl = of_parse_phandle(dev->of_node,
>  						     "nvidia,gpio-controller",
> @@ -775,14 +775,19 @@ static int tegra_hte_probe(struct platform_device *pdev)
>  				return -ENODEV;
>  			}
>  
> -			hte_dev->c = gpiochip_find(gpio_ctrl,
> -						   tegra_gpiochip_match);
> +			hte_dev->gdev =
> +				gpio_device_find_by_fwnode(of_fnode_handle(gpio_ctrl));
>  			of_node_put(gpio_ctrl);
>  		}
>  
> -		if (!hte_dev->c)
> +		if (!hte_dev->gdev)
>  			return dev_err_probe(dev, -EPROBE_DEFER,
>  					     "wait for gpio controller\n");
> +
> +		ret = devm_add_action_or_reset(dev, tegra_hte_put_gpio_device,
> +					       hte_dev->gdev);
> +		if (ret)
> +			return ret;
>  	}
>  
>  	hte_dev->chip = gc;

Looks good to me, I will wait for others to comment and will test out (2,3,4
also) probably end of the day 11th Oct.
  
Dipen Patel Oct. 10, 2023, 7:31 p.m. UTC | #2
On 10/10/23 9:19 AM, Dipen Patel wrote:
> On 10/10/23 8:17 AM, Andy Shevchenko wrote:
>> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>>
>> Using struct gpio_chip is not safe as it will disappear if the
>> underlying driver is unbound for any reason. Switch to using reference
>> counted struct gpio_device and its dedicated accessors.
>>
>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>> Tested-by: Dipen Patel <dipenp@nvidia.com>
>> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
>> [andy: used gpio_device_find_by_fwnode()]
>> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> ---
>>  drivers/hte/hte-tegra194.c | 33 +++++++++++++++++++--------------
>>  1 file changed, 19 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/hte/hte-tegra194.c b/drivers/hte/hte-tegra194.c
>> index 9fd3c00ff695..339ff5921ec8 100644
>> --- a/drivers/hte/hte-tegra194.c
>> +++ b/drivers/hte/hte-tegra194.c
>> @@ -132,7 +132,7 @@ struct tegra_hte_soc {
>>  	const struct tegra_hte_data *prov_data;
>>  	struct tegra_hte_line_data *line_data;
>>  	struct hte_chip *chip;
>> -	struct gpio_chip *c;
>> +	struct gpio_device *gdev;
>>  	void __iomem *regs;
>>  };
>>  
>> @@ -421,7 +421,7 @@ static int tegra_hte_line_xlate(struct hte_chip *gc,
>>  	 * HTE/GTE namespace.
>>  	 */
>>  	if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && !args) {
>> -		line_id = desc->attr.line_id - gs->c->base;
>> +		line_id = desc->attr.line_id - gpio_device_get_base(gs->gdev);
>>  		map = gs->prov_data->map;
>>  		map_sz = gs->prov_data->map_sz;
>>  	} else if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && args) {
>> @@ -643,12 +643,15 @@ static irqreturn_t tegra_hte_isr(int irq, void *dev_id)
>>  static bool tegra_hte_match_from_linedata(const struct hte_chip *chip,
>>  					  const struct hte_ts_desc *hdesc)
>>  {
>> +	struct gpio_device *gdev __free(gpio_device_put) = NULL;
>>  	struct tegra_hte_soc *hte_dev = chip->data;
>>  
>>  	if (!hte_dev || (hte_dev->prov_data->type != HTE_TEGRA_TYPE_GPIO))
>>  		return false;
>>  
>> -	return hte_dev->c == gpiod_to_chip(hdesc->attr.line_data);
>> +	gdev = gpiod_to_device(hdesc->attr.line_data);
>> +
>> +	return hte_dev->gdev == gdev;
>>  }
>>  
>>  static const struct of_device_id tegra_hte_of_match[] = {
>> @@ -676,14 +679,11 @@ static void tegra_gte_disable(void *data)
>>  	tegra_hte_writel(gs, HTE_TECTRL, 0);
>>  }
>>  
>> -static int tegra_get_gpiochip_from_name(struct gpio_chip *chip, void *data)
>> +static void tegra_hte_put_gpio_device(void *data)
>>  {
>> -	return !strcmp(chip->label, data);
>> -}
>> +	struct gpio_device *gdev = data;
>>  
>> -static int tegra_gpiochip_match(struct gpio_chip *chip, void *data)
>> -{
>> -	return chip->fwnode == of_node_to_fwnode(data);
>> +	gpio_device_put(gdev);
>>  }
>>  
>>  static int tegra_hte_probe(struct platform_device *pdev)
>> @@ -763,8 +763,8 @@ static int tegra_hte_probe(struct platform_device *pdev)
>>  
>>  		if (of_device_is_compatible(dev->of_node,
>>  					    "nvidia,tegra194-gte-aon")) {
>> -			hte_dev->c = gpiochip_find("tegra194-gpio-aon",
>> -						tegra_get_gpiochip_from_name);
>> +			hte_dev->gdev =
>> +				gpio_device_find_by_label("tegra194-gpio-aon");
>>  		} else {
>>  			gpio_ctrl = of_parse_phandle(dev->of_node,
>>  						     "nvidia,gpio-controller",
>> @@ -775,14 +775,19 @@ static int tegra_hte_probe(struct platform_device *pdev)
>>  				return -ENODEV;
>>  			}
>>  
>> -			hte_dev->c = gpiochip_find(gpio_ctrl,
>> -						   tegra_gpiochip_match);
>> +			hte_dev->gdev =
>> +				gpio_device_find_by_fwnode(of_fnode_handle(gpio_ctrl));

I think there is typo for of_fnode*. Should it be of_fwnode*?

>>  			of_node_put(gpio_ctrl);
>>  		}
>>  
>> -		if (!hte_dev->c)
>> +		if (!hte_dev->gdev)
>>  			return dev_err_probe(dev, -EPROBE_DEFER,
>>  					     "wait for gpio controller\n");
>> +
>> +		ret = devm_add_action_or_reset(dev, tegra_hte_put_gpio_device,
>> +					       hte_dev->gdev);
>> +		if (ret)
>> +			return ret;
>>  	}
>>  
>>  	hte_dev->chip = gc;
> 
> Looks good to me, I will wait for others to comment and will test out (2,3,4
> also) probably end of the day 11th Oct.
>
  
Andy Shevchenko Oct. 11, 2023, 5:54 a.m. UTC | #3
On Tue, Oct 10, 2023 at 10:31 PM Dipen Patel <dipenp@nvidia.com> wrote:
> On 10/10/23 9:19 AM, Dipen Patel wrote:
> > On 10/10/23 8:17 AM, Andy Shevchenko wrote:

> >> +                    hte_dev->gdev =
> >> +                            gpio_device_find_by_fwnode(of_fnode_handle(gpio_ctrl));
>
> I think there is typo for of_fnode*. Should it be of_fwnode*?

Yep, it's a typo, can you. fix manually for the test, please?
  
Dipen Patel Oct. 11, 2023, 6:05 p.m. UTC | #4
On 10/10/23 10:54 PM, Andy Shevchenko wrote:
> On Tue, Oct 10, 2023 at 10:31 PM Dipen Patel <dipenp@nvidia.com> wrote:
>> On 10/10/23 9:19 AM, Dipen Patel wrote:
>>> On 10/10/23 8:17 AM, Andy Shevchenko wrote:
> 
>>>> +                    hte_dev->gdev =
>>>> +                            gpio_device_find_by_fwnode(of_fnode_handle(gpio_ctrl));
>>
>> I think there is typo for of_fnode*. Should it be of_fwnode*?
> 
> Yep, it's a typo, can you. fix manually for the test, please?
> 
After manually correcting the typo...

Tested-by: Dipen Patel <dipenp@nvidia.com>
  

Patch

diff --git a/drivers/hte/hte-tegra194.c b/drivers/hte/hte-tegra194.c
index 9fd3c00ff695..339ff5921ec8 100644
--- a/drivers/hte/hte-tegra194.c
+++ b/drivers/hte/hte-tegra194.c
@@ -132,7 +132,7 @@  struct tegra_hte_soc {
 	const struct tegra_hte_data *prov_data;
 	struct tegra_hte_line_data *line_data;
 	struct hte_chip *chip;
-	struct gpio_chip *c;
+	struct gpio_device *gdev;
 	void __iomem *regs;
 };
 
@@ -421,7 +421,7 @@  static int tegra_hte_line_xlate(struct hte_chip *gc,
 	 * HTE/GTE namespace.
 	 */
 	if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && !args) {
-		line_id = desc->attr.line_id - gs->c->base;
+		line_id = desc->attr.line_id - gpio_device_get_base(gs->gdev);
 		map = gs->prov_data->map;
 		map_sz = gs->prov_data->map_sz;
 	} else if (gs->prov_data->type == HTE_TEGRA_TYPE_GPIO && args) {
@@ -643,12 +643,15 @@  static irqreturn_t tegra_hte_isr(int irq, void *dev_id)
 static bool tegra_hte_match_from_linedata(const struct hte_chip *chip,
 					  const struct hte_ts_desc *hdesc)
 {
+	struct gpio_device *gdev __free(gpio_device_put) = NULL;
 	struct tegra_hte_soc *hte_dev = chip->data;
 
 	if (!hte_dev || (hte_dev->prov_data->type != HTE_TEGRA_TYPE_GPIO))
 		return false;
 
-	return hte_dev->c == gpiod_to_chip(hdesc->attr.line_data);
+	gdev = gpiod_to_device(hdesc->attr.line_data);
+
+	return hte_dev->gdev == gdev;
 }
 
 static const struct of_device_id tegra_hte_of_match[] = {
@@ -676,14 +679,11 @@  static void tegra_gte_disable(void *data)
 	tegra_hte_writel(gs, HTE_TECTRL, 0);
 }
 
-static int tegra_get_gpiochip_from_name(struct gpio_chip *chip, void *data)
+static void tegra_hte_put_gpio_device(void *data)
 {
-	return !strcmp(chip->label, data);
-}
+	struct gpio_device *gdev = data;
 
-static int tegra_gpiochip_match(struct gpio_chip *chip, void *data)
-{
-	return chip->fwnode == of_node_to_fwnode(data);
+	gpio_device_put(gdev);
 }
 
 static int tegra_hte_probe(struct platform_device *pdev)
@@ -763,8 +763,8 @@  static int tegra_hte_probe(struct platform_device *pdev)
 
 		if (of_device_is_compatible(dev->of_node,
 					    "nvidia,tegra194-gte-aon")) {
-			hte_dev->c = gpiochip_find("tegra194-gpio-aon",
-						tegra_get_gpiochip_from_name);
+			hte_dev->gdev =
+				gpio_device_find_by_label("tegra194-gpio-aon");
 		} else {
 			gpio_ctrl = of_parse_phandle(dev->of_node,
 						     "nvidia,gpio-controller",
@@ -775,14 +775,19 @@  static int tegra_hte_probe(struct platform_device *pdev)
 				return -ENODEV;
 			}
 
-			hte_dev->c = gpiochip_find(gpio_ctrl,
-						   tegra_gpiochip_match);
+			hte_dev->gdev =
+				gpio_device_find_by_fwnode(of_fnode_handle(gpio_ctrl));
 			of_node_put(gpio_ctrl);
 		}
 
-		if (!hte_dev->c)
+		if (!hte_dev->gdev)
 			return dev_err_probe(dev, -EPROBE_DEFER,
 					     "wait for gpio controller\n");
+
+		ret = devm_add_action_or_reset(dev, tegra_hte_put_gpio_device,
+					       hte_dev->gdev);
+		if (ret)
+			return ret;
 	}
 
 	hte_dev->chip = gc;