pinctrl: support gpio request deferred probing

Dong Aisheng · linusw · commit 4650b7cbea4d · 2012-05-02T01:14:20.000+02:00
As pinctrl handles, it may be possible the pinctrl gpio ranges
are still not got registered when user call pinctrl_gpio_request.
Thus, add defer support for it too.

Signed-off-by: Dong Aisheng &lt;dong.aisheng@linaro.org&gt;
Acked-by: Stephen Warren &lt;swarren@wwwdotorg.org&gt;
Signed-off-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
@@ -291,7 +291,8 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio)
  *
  * Find the pin controller handling a certain GPIO pin from the pinspace of
  * the GPIO subsystem, return the device and the matching GPIO range. Returns
- * negative if the GPIO range could not be found in any device.
+ * -EPROBE_DEFER if the GPIO range could not be found in any device since it
+ * may still have not been registered.
  */
 static int pinctrl_get_device_gpio_range(unsigned gpio,
 					 struct pinctrl_dev **outdev,
@@ -311,7 +312,7 @@ static int pinctrl_get_device_gpio_range(unsigned gpio,
 		}
 	}
 
-	return -EINVAL;
+	return -EPROBE_DEFER;
 }
 
 /**
@@ -397,7 +398,7 @@ int pinctrl_request_gpio(unsigned gpio)
 	ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
 	if (ret) {
 		mutex_unlock(&pinctrl_mutex);
-		return -EINVAL;
+		return ret;
 	}
 
 	/* Convert to the pin controllers number space */

Original file line number	Diff line number	Diff line change
`@@ -291,7 +291,8 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio)`
`291`	`291`	`*`
`292`	`292`	`* Find the pin controller handling a certain GPIO pin from the pinspace of`
`293`	`293`	`* the GPIO subsystem, return the device and the matching GPIO range. Returns`
`294`		`- * negative if the GPIO range could not be found in any device.`
	`294`	`+ * -EPROBE_DEFER if the GPIO range could not be found in any device since it`
	`295`	`+ * may still have not been registered.`
`295`	`296`	`*/`
`296`	`297`	`static int pinctrl_get_device_gpio_range(unsigned gpio,`
`297`	`298`	`struct pinctrl_dev **outdev,`
`@@ -311,7 +312,7 @@ static int pinctrl_get_device_gpio_range(unsigned gpio,`
`311`	`312`	`}`
`312`	`313`	`}`
`313`	`314`
`314`		`- return -EINVAL;`
	`315`	`+ return -EPROBE_DEFER;`
`315`	`316`	`}`
`316`	`317`
`317`	`318`	`/**`
`@@ -397,7 +398,7 @@ int pinctrl_request_gpio(unsigned gpio)`
`397`	`398`	`ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);`
`398`	`399`	`if (ret) {`
`399`	`400`	`mutex_unlock(&pinctrl_mutex);`
`400`		`- return -EINVAL;`
	`401`	`+ return ret;`
`401`	`402`	`}`
`402`	`403`
`403`	`404`	`/* Convert to the pin controllers number space */`