Re: [PATCH 04/10] platform/x86: toshiba_acpi: use device-managed functions for input device

2021-03-29 Thread Jonathan Cameron
On Wed, 24 Mar 2021 14:55:42 +0200
Alexandru Ardelean  wrote:

> This change uses device managed functions to handle the deregistration of
> the keyboard resources when the refcount of the parent device goes to zero.
> 
> For the input device devm_input_allocate_device() must be used, and after
> that it will be bound also for auto-deregistration when
> input_device_register() is called.
> 
> The work object is registered for uninit with devm_add_action(), which will
> be called on device unregister only.
> 
> The i8042 filter is registered with devm_add_action() as well, but it is
> done last in the toshiba_acpi_setup_keyboard() function. This is a little
> quirky, because this relies on the fact that there can a single
> toshiba_acpi_dev object.

I think this is the wrong approach here.  Given function can fail
without probe() returning an error, go up one level and treat this whole
function as something to be device managed.  That way you can register
the unwind function only if the call in probe succeeds.

Jonathan


> 
> Signed-off-by: Alexandru Ardelean 
> ---
>  drivers/platform/x86/toshiba_acpi.c | 55 +++--
>  1 file changed, 36 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/platform/x86/toshiba_acpi.c 
> b/drivers/platform/x86/toshiba_acpi.c
> index 53ef565378ef..556f2cc99bad 100644
> --- a/drivers/platform/x86/toshiba_acpi.c
> +++ b/drivers/platform/x86/toshiba_acpi.c
> @@ -186,7 +186,6 @@ struct toshiba_acpi_dev {
>   unsigned int video_supported:1;
>   unsigned int fan_supported:1;
>   unsigned int system_event_supported:1;
> - unsigned int ntfy_supported:1;
>   unsigned int info_supported:1;
>   unsigned int tr_backlight_supported:1;
>   unsigned int kbd_illum_supported:1;
> @@ -2756,9 +2755,23 @@ static void toshiba_acpi_process_hotkeys(struct 
> toshiba_acpi_dev *dev)
>   }
>  }
>  
> -static int toshiba_acpi_setup_keyboard(struct toshiba_acpi_dev *dev)
> +static void toshiba_acpi_cancel_hotkey_work(void *data)
> +{
> + struct work_struct *hotkey_work = data;
> +
> + cancel_work_sync(hotkey_work);
> +}
> +
> +static void toshiba_acpi_i8042_remove_filter(void *data)
> +{
> + i8042_remove_filter(toshiba_acpi_i8042_filter);
> +}
> +
> +static int toshiba_acpi_setup_keyboard(struct device *parent,
> +struct toshiba_acpi_dev *dev)
>  {
>   const struct key_entry *keymap = toshiba_acpi_keymap;
> + bool ntfy_supported = false;
>   acpi_handle ec_handle;
>   int error;
>  
> @@ -2779,7 +2792,7 @@ static int toshiba_acpi_setup_keyboard(struct 
> toshiba_acpi_dev *dev)
>   if (toshiba_hotkey_event_type_get(dev, >hotkey_event_type))
>   pr_notice("Unable to query Hotkey Event Type\n");
>  
> - dev->hotkey_dev = input_allocate_device();
> + dev->hotkey_dev = devm_input_allocate_device(parent);

Hmm. Doing this within a function that can fail without resulting in driver 
probe failure
is rather messy.  I think you should call a manual free so this isn't left 
around until
driver remove.

Or decide this function is too complex and do the devm_ management one layer 
out using
a devm_add_action_or_reset(dev, toshiba_acpi_unsetup_keyboard, *) or similar to 
do
it in one go.  That would only be registered if this function succeeded in the 
first place.

>   if (!dev->hotkey_dev)
>   return -ENOMEM;
>  
> @@ -2798,7 +2811,7 @@ static int toshiba_acpi_setup_keyboard(struct 
> toshiba_acpi_dev *dev)
>   dev->hotkey_event_type);
>   error = sparse_keymap_setup(dev->hotkey_dev, keymap, NULL);
>   if (error)
> - goto err_free_dev;
> + goto err_null_dev;
>  
>   /*
>* For some machines the SCI responsible for providing hotkey
> @@ -2811,13 +2824,19 @@ static int toshiba_acpi_setup_keyboard(struct 
> toshiba_acpi_dev *dev)
>   if (ec_handle && acpi_has_method(ec_handle, "NTFY")) {
>   INIT_WORK(>hotkey_work, toshiba_acpi_hotkey_work);
>  
> + error = devm_add_action(parent,
> + toshiba_acpi_cancel_hotkey_work,
> + >hotkey_work);
> + if (error)
> + return error;
> +
>   error = i8042_install_filter(toshiba_acpi_i8042_filter);
>   if (error) {
>   pr_err("Error installing key filter\n");
> - goto err_free_dev;
> + return error;

Does this not want to do goto err_null_dev?
Same with the one above.

>   }
>  
> - dev->ntfy_supported = 1;
> + ntfy_supported = true;
>   }
>  
>   /*
> @@ -2840,13 +2859,19 @@ static int toshiba_acpi_setup_keyboard(struct 
> toshiba_acpi_dev *dev)
>   goto err_remove_filter;
>   }
>  
> + if (ntfy_supported) {
> + error = devm_add_action(parent,
> +   

[PATCH 04/10] platform/x86: toshiba_acpi: use device-managed functions for input device

2021-03-24 Thread Alexandru Ardelean
This change uses device managed functions to handle the deregistration of
the keyboard resources when the refcount of the parent device goes to zero.

For the input device devm_input_allocate_device() must be used, and after
that it will be bound also for auto-deregistration when
input_device_register() is called.

The work object is registered for uninit with devm_add_action(), which will
be called on device unregister only.

The i8042 filter is registered with devm_add_action() as well, but it is
done last in the toshiba_acpi_setup_keyboard() function. This is a little
quirky, because this relies on the fact that there can a single
toshiba_acpi_dev object.

Signed-off-by: Alexandru Ardelean 
---
 drivers/platform/x86/toshiba_acpi.c | 55 +++--
 1 file changed, 36 insertions(+), 19 deletions(-)

diff --git a/drivers/platform/x86/toshiba_acpi.c 
b/drivers/platform/x86/toshiba_acpi.c
index 53ef565378ef..556f2cc99bad 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -186,7 +186,6 @@ struct toshiba_acpi_dev {
unsigned int video_supported:1;
unsigned int fan_supported:1;
unsigned int system_event_supported:1;
-   unsigned int ntfy_supported:1;
unsigned int info_supported:1;
unsigned int tr_backlight_supported:1;
unsigned int kbd_illum_supported:1;
@@ -2756,9 +2755,23 @@ static void toshiba_acpi_process_hotkeys(struct 
toshiba_acpi_dev *dev)
}
 }
 
-static int toshiba_acpi_setup_keyboard(struct toshiba_acpi_dev *dev)
+static void toshiba_acpi_cancel_hotkey_work(void *data)
+{
+   struct work_struct *hotkey_work = data;
+
+   cancel_work_sync(hotkey_work);
+}
+
+static void toshiba_acpi_i8042_remove_filter(void *data)
+{
+   i8042_remove_filter(toshiba_acpi_i8042_filter);
+}
+
+static int toshiba_acpi_setup_keyboard(struct device *parent,
+  struct toshiba_acpi_dev *dev)
 {
const struct key_entry *keymap = toshiba_acpi_keymap;
+   bool ntfy_supported = false;
acpi_handle ec_handle;
int error;
 
@@ -2779,7 +2792,7 @@ static int toshiba_acpi_setup_keyboard(struct 
toshiba_acpi_dev *dev)
if (toshiba_hotkey_event_type_get(dev, >hotkey_event_type))
pr_notice("Unable to query Hotkey Event Type\n");
 
-   dev->hotkey_dev = input_allocate_device();
+   dev->hotkey_dev = devm_input_allocate_device(parent);
if (!dev->hotkey_dev)
return -ENOMEM;
 
@@ -2798,7 +2811,7 @@ static int toshiba_acpi_setup_keyboard(struct 
toshiba_acpi_dev *dev)
dev->hotkey_event_type);
error = sparse_keymap_setup(dev->hotkey_dev, keymap, NULL);
if (error)
-   goto err_free_dev;
+   goto err_null_dev;
 
/*
 * For some machines the SCI responsible for providing hotkey
@@ -2811,13 +2824,19 @@ static int toshiba_acpi_setup_keyboard(struct 
toshiba_acpi_dev *dev)
if (ec_handle && acpi_has_method(ec_handle, "NTFY")) {
INIT_WORK(>hotkey_work, toshiba_acpi_hotkey_work);
 
+   error = devm_add_action(parent,
+   toshiba_acpi_cancel_hotkey_work,
+   >hotkey_work);
+   if (error)
+   return error;
+
error = i8042_install_filter(toshiba_acpi_i8042_filter);
if (error) {
pr_err("Error installing key filter\n");
-   goto err_free_dev;
+   return error;
}
 
-   dev->ntfy_supported = 1;
+   ntfy_supported = true;
}
 
/*
@@ -2840,13 +2859,19 @@ static int toshiba_acpi_setup_keyboard(struct 
toshiba_acpi_dev *dev)
goto err_remove_filter;
}
 
+   if (ntfy_supported) {
+   error = devm_add_action(parent,
+   toshiba_acpi_i8042_remove_filter,
+   NULL);
+   goto err_remove_filter;
+   }
+
return 0;
 
- err_remove_filter:
-   if (dev->ntfy_supported)
+err_remove_filter:
+   if (ntfy_supported)
i8042_remove_filter(toshiba_acpi_i8042_filter);
- err_free_dev:
-   input_free_device(dev->hotkey_dev);
+err_null_dev:
dev->hotkey_dev = NULL;
return error;
 }
@@ -2974,14 +2999,6 @@ static int toshiba_acpi_remove(struct acpi_device 
*acpi_dev)
sysfs_remove_group(>acpi_dev->dev.kobj,
   _attr_group);
 
-   if (dev->ntfy_supported) {
-   i8042_remove_filter(toshiba_acpi_i8042_filter);
-   cancel_work_sync(>hotkey_work);
-   }
-
-   if (dev->hotkey_dev)
-   input_unregister_device(dev->hotkey_dev);
-
backlight_device_unregister(dev->backlight_dev);