[2/4] pinctrl: samsung: Register pinctrl before GPIO
diff mbox

Message ID 1486980666-7143-2-git-send-email-ckeepax@opensource.wolfsonmicro.com
State Not Applicable
Headers show

Commit Message

Charles Keepax Feb. 13, 2017, 10:11 a.m. UTC
If we request a GPIO hog, then gpiochip_add_data will attempt to request
some of its own GPIOs. The driver also uses gpiochip_generic_request
which means that for any GPIO request to succeed the pinctrl needs to be
registered. Currently however the driver registers the GPIO and then the
pinctrl meaning all GPIO hog requests will fail, which then in turn causes
the whole driver to fail probe. Fix this up by ensuring we register the
pinctrl first.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 drivers/pinctrl/samsung/pinctrl-samsung.c | 32 +++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

Comments

Krzysztof Kozlowski Feb. 15, 2017, 5:36 p.m. UTC | #1
On Mon, Feb 13, 2017 at 10:11:04AM +0000, Charles Keepax wrote:
> If we request a GPIO hog, then gpiochip_add_data will attempt to request
> some of its own GPIOs. The driver also uses gpiochip_generic_request
> which means that for any GPIO request to succeed the pinctrl needs to be
> registered. Currently however the driver registers the GPIO and then the
> pinctrl meaning all GPIO hog requests will fail, which then in turn causes
> the whole driver to fail probe. Fix this up by ensuring we register the
> pinctrl first.
> 
> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> ---
>  drivers/pinctrl/samsung/pinctrl-samsung.c | 32 +++++++++++++++----------------

I think the code makes sense altough the description describes
theoretical issue - we do not use GPIO hogs. Of course out of tree DTS
could use them... so maybe mention that this is not an existing case?

For the code itself:
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof


>  1 file changed, 16 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
> index d79eada..1134bc3 100644
> --- a/drivers/pinctrl/samsung/pinctrl-samsung.c
> +++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
> @@ -893,6 +893,19 @@ static int samsung_pinctrl_register(struct platform_device *pdev,
>  	return 0;
>  }
>  
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch
diff mbox

diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
index d79eada..1134bc3 100644
--- a/drivers/pinctrl/samsung/pinctrl-samsung.c
+++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
@@ -893,6 +893,19 @@  static int samsung_pinctrl_register(struct platform_device *pdev,
 	return 0;
 }
 
+/* unregister the pinctrl interface with the pinctrl subsystem */
+static int samsung_pinctrl_unregister(struct platform_device *pdev,
+				      struct samsung_pinctrl_drv_data *drvdata)
+{
+	struct samsung_pin_bank *bank = drvdata->pin_banks;
+	int i;
+
+	for (i = 0; i < drvdata->nr_banks; ++i, ++bank)
+		pinctrl_remove_gpio_range(drvdata->pctl_dev, &bank->grange);
+
+	return 0;
+}
+
 static const struct gpio_chip samsung_gpiolib_chip = {
 	.request = gpiochip_generic_request,
 	.free = gpiochip_generic_free,
@@ -939,19 +952,6 @@  static int samsung_gpiolib_register(struct platform_device *pdev,
 	return ret;
 }
 
-/* unregister the gpiolib interface with the gpiolib subsystem */
-static int samsung_gpiolib_unregister(struct platform_device *pdev,
-				      struct samsung_pinctrl_drv_data *drvdata)
-{
-	struct samsung_pin_bank *bank = drvdata->pin_banks;
-	int i;
-
-	for (i = 0; i < drvdata->nr_banks; ++i, ++bank)
-		gpiochip_remove(&bank->gpio_chip);
-
-	return 0;
-}
-
 /* retrieve the soc specific data */
 static const struct samsung_pin_ctrl *
 samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
@@ -1063,13 +1063,13 @@  static int samsung_pinctrl_probe(struct platform_device *pdev)
 			return PTR_ERR(drvdata->retention_ctrl);
 	}
 
-	ret = samsung_gpiolib_register(pdev, drvdata);
+	ret = samsung_pinctrl_register(pdev, drvdata);
 	if (ret)
 		return ret;
 
-	ret = samsung_pinctrl_register(pdev, drvdata);
+	ret = samsung_gpiolib_register(pdev, drvdata);
 	if (ret) {
-		samsung_gpiolib_unregister(pdev, drvdata);
+		samsung_pinctrl_unregister(pdev, drvdata);
 		return ret;
 	}