diff options
| author | Oleksandr Suvorov <oleksandr.suvorov@toradex.com> | 2019-09-18 15:32:45 +0300 |
|---|---|---|
| committer | Oleksandr Suvorov <oleksandr.suvorov@toradex.com> | 2019-09-18 18:48:36 +0300 |
| commit | ab73141be9d799c6bac71398f0fbd95a55d4fabe (patch) | |
| tree | fa4494ade011093aac89bdb8bff669721d5459c0 | |
| parent | cd0060a616b965de788837d822ce0bc3a29b9ce3 (diff) | |
power: reset: gpio-poweroff: add force-mode
Property "force-mode" tells the driver to replace previously
initialized power-off kernel hook and allows gpio-poweroff to
probe and operate successfully in any case.
Related-to: #42589
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
| -rw-r--r-- | Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt | 3 | ||||
| -rw-r--r-- | drivers/power/reset/gpio-poweroff.c | 27 |
2 files changed, 24 insertions, 6 deletions
diff --git a/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt b/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt index e62d53d844cc..e680925894c9 100644 --- a/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt +++ b/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt @@ -27,6 +27,9 @@ Optional properties: it to an output when the power-off handler is called. If this optional property is not specified, the GPIO is initialized as an output in its inactive state. +- force-mode: Force replacing pm_power_off kernel hook. + If this optional property is not specified, the driver will fail to + load if someone has registered the pm_power_off hook earlier. Examples: diff --git a/drivers/power/reset/gpio-poweroff.c b/drivers/power/reset/gpio-poweroff.c index be3d81ff51cc..c96be0fa39bf 100644 --- a/drivers/power/reset/gpio-poweroff.c +++ b/drivers/power/reset/gpio-poweroff.c @@ -24,6 +24,7 @@ * since pm_power_off itself is global. */ static struct gpio_desc *reset_gpio; +static void *prev_pm_power_off = NULL; static void gpio_poweroff_do_poweroff(void) { @@ -48,14 +49,28 @@ static void gpio_poweroff_do_poweroff(void) static int gpio_poweroff_probe(struct platform_device *pdev) { bool input = false; + bool force = false; enum gpiod_flags flags; - /* If a pm_power_off function has already been added, leave it alone */ + + force = of_property_read_bool(pdev->dev.of_node, "force-mode"); + + /* + * If a pm_power_off function has already been added, leave it alone, + * if force-mode is not enabled. + */ if (pm_power_off != NULL) { - dev_err(&pdev->dev, - "%s: pm_power_off function already registered", - __func__); - return -EBUSY; + if (force) { + dev_warn(&pdev->dev, + "%s: pm_power_off function replaced", + __func__); + prev_pm_power_off = pm_power_off; + } else { + dev_err(&pdev->dev, + "%s: pm_power_off function already registered", + __func__); + return -EBUSY; + } } input = of_property_read_bool(pdev->dev.of_node, "input"); @@ -75,7 +90,7 @@ static int gpio_poweroff_probe(struct platform_device *pdev) static int gpio_poweroff_remove(struct platform_device *pdev) { if (pm_power_off == &gpio_poweroff_do_poweroff) - pm_power_off = NULL; + pm_power_off = prev_pm_power_off; return 0; } |