Re: [PATCH v4 18/35] platform/x86/classmate-laptop: Move handler installing logic to driver

["Wilczynski, Michal" <michal.wilczynski@intel.com>]

On 6/2/2023 12:29 PM, Thadeu Lima de Souza Cascardo wrote:
> On Thu, Jun 01, 2023 at 03:17:21PM +0200, Michal Wilczynski wrote:
>> Currently logic for installing notifications from ACPI devices is
>> implemented using notify callback in struct acpi_driver. Preparations
>> are being made to replace acpi_driver with more generic struct
>> platform_driver, which doesn't contain notify callback. Furthermore
>> as of now handlers are being called indirectly through
>> acpi_notify_device(), which decreases performance.
>>
>> Call acpi_device_install_event_handler() at the end of .add() callback.
>> Call acpi_device_remove_event_handler() at the beginning of .remove()
>> callback. Change arguments passed to the notify callback to match with
>> what's required by acpi_device_install_event_handler().
>>
>> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
>> ---
>>  drivers/platform/x86/classmate-laptop.c | 53 +++++++++++++++++++------
>>  1 file changed, 41 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/platform/x86/classmate-laptop.c b/drivers/platform/x86/classmate-laptop.c
>> index 2edaea2492df..2d36abf5ecfe 100644
>> --- a/drivers/platform/x86/classmate-laptop.c
>> +++ b/drivers/platform/x86/classmate-laptop.c
>> @@ -180,8 +180,9 @@ static acpi_status cmpc_get_accel_v4(acpi_handle handle,
>>  	return status;
>>  }
>>  
>> -static void cmpc_accel_handler_v4(struct acpi_device *dev, u32 event)
>> +static void cmpc_accel_handler_v4(acpi_handle handle, u32 event, void *data)
>>  {
>> +	struct acpi_device *dev = data;
>>  	if (event == 0x81) {
>>  		int16_t x, y, z;
>>  		acpi_status status;
>> @@ -407,6 +408,11 @@ static int cmpc_accel_add_v4(struct acpi_device *acpi)
>>  	inputdev = dev_get_drvdata(&acpi->dev);
>>  	dev_set_drvdata(&inputdev->dev, accel);
>>  
>> +	error = acpi_device_install_event_handler(acpi, ACPI_DEVICE_NOTIFY,
>> +						  cmpc_accel_handler_v4);
>> +	if (error)
>> +		goto failed_input;
>> +
> In all cases, acpi_device_install_event_handler is being called after
> cmpc_add_acpi_notify_device, which allocates and registers an input
> device.
>
> You should cleanup in case acpi_device_install_event_handler fails and
> call cmpc_remove_acpi_notify_device.
>
> Cascardo.

Hi Cascardo

Yeah I see this now, I'm not freeing the resource in the error path properly,
will add another label for example 'failed_notify_install' that would call
cmpc_remove_acpi_notify_device,

Thanks !
Michał

>
>>  	return 0;
>>  
>>  failed_input:
>> @@ -420,6 +426,7 @@ static int cmpc_accel_add_v4(struct acpi_device *acpi)
>>  
>>  static void cmpc_accel_remove_v4(struct acpi_device *acpi)
>>  {
>> +	acpi_device_remove_event_handler(acpi, ACPI_DEVICE_NOTIFY, cmpc_accel_handler_v4);
>>  	device_remove_file(&acpi->dev, &cmpc_accel_sensitivity_attr_v4);
>>  	device_remove_file(&acpi->dev, &cmpc_accel_g_select_attr_v4);
>>  	cmpc_remove_acpi_notify_device(acpi);
>> @@ -441,7 +448,6 @@ static struct acpi_driver cmpc_accel_acpi_driver_v4 = {
>>  	.ops = {
>>  		.add = cmpc_accel_add_v4,
>>  		.remove = cmpc_accel_remove_v4,
>> -		.notify = cmpc_accel_handler_v4,
>>  	},
>>  	.drv.pm = &cmpc_accel_pm,
>>  };
>> @@ -523,8 +529,10 @@ static acpi_status cmpc_get_accel(acpi_handle handle,
>>  	return status;
>>  }
>>  
>> -static void cmpc_accel_handler(struct acpi_device *dev, u32 event)
>> +static void cmpc_accel_handler(acpi_handle handle, u32 event, void *data)
>>  {
>> +	struct acpi_device *dev = data;
>> +
>>  	if (event == 0x81) {
>>  		unsigned char x, y, z;
>>  		acpi_status status;
>> @@ -639,6 +647,11 @@ static int cmpc_accel_add(struct acpi_device *acpi)
>>  	inputdev = dev_get_drvdata(&acpi->dev);
>>  	dev_set_drvdata(&inputdev->dev, accel);
>>  
>> +	error = acpi_device_install_event_handler(acpi, ACPI_DEVICE_NOTIFY,
>> +						  cmpc_accel_handler);
>> +	if (error)
>> +		goto failed_input;
>> +
>>  	return 0;
>>  
>>  failed_input:
>> @@ -650,6 +663,7 @@ static int cmpc_accel_add(struct acpi_device *acpi)
>>  
>>  static void cmpc_accel_remove(struct acpi_device *acpi)
>>  {
>> +	acpi_device_remove_event_handler(acpi, ACPI_DEVICE_NOTIFY, cmpc_accel_handler);
>>  	device_remove_file(&acpi->dev, &cmpc_accel_sensitivity_attr);
>>  	cmpc_remove_acpi_notify_device(acpi);
>>  }
>> @@ -667,7 +681,6 @@ static struct acpi_driver cmpc_accel_acpi_driver = {
>>  	.ops = {
>>  		.add = cmpc_accel_add,
>>  		.remove = cmpc_accel_remove,
>> -		.notify = cmpc_accel_handler,
>>  	}
>>  };
>>  
>> @@ -693,8 +706,9 @@ static acpi_status cmpc_get_tablet(acpi_handle handle,
>>  	return status;
>>  }
>>  
>> -static void cmpc_tablet_handler(struct acpi_device *dev, u32 event)
>> +static void cmpc_tablet_handler(acpi_handle handle, u32 event, void *data)
>>  {
>> +	struct acpi_device *dev = data;
>>  	unsigned long long val = 0;
>>  	struct input_dev *inputdev = dev_get_drvdata(&dev->dev);
>>  
>> @@ -723,12 +737,20 @@ static void cmpc_tablet_idev_init(struct input_dev *inputdev)
>>  
>>  static int cmpc_tablet_add(struct acpi_device *acpi)
>>  {
>> -	return cmpc_add_acpi_notify_device(acpi, "cmpc_tablet",
>> -					   cmpc_tablet_idev_init);
>> +	int ret;
>> +
>> +	ret = cmpc_add_acpi_notify_device(acpi, "cmpc_tablet",
>> +					  cmpc_tablet_idev_init);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return acpi_device_install_event_handler(acpi, ACPI_DEVICE_NOTIFY,
>> +						 cmpc_tablet_handler);
>>  }
>>  
>>  static void cmpc_tablet_remove(struct acpi_device *acpi)
>>  {
>> +	acpi_device_remove_event_handler(acpi, ACPI_DEVICE_NOTIFY, cmpc_tablet_handler);
>>  	cmpc_remove_acpi_notify_device(acpi);
>>  }
>>  
>> @@ -761,7 +783,6 @@ static struct acpi_driver cmpc_tablet_acpi_driver = {
>>  	.ops = {
>>  		.add = cmpc_tablet_add,
>>  		.remove = cmpc_tablet_remove,
>> -		.notify = cmpc_tablet_handler,
>>  	},
>>  	.drv.pm = &cmpc_tablet_pm,
>>  };
>> @@ -1026,8 +1047,9 @@ static int cmpc_keys_codes[] = {
>>  	KEY_MAX
>>  };
>>  
>> -static void cmpc_keys_handler(struct acpi_device *dev, u32 event)
>> +static void cmpc_keys_handler(acpi_handle handle, u32 event, void *data)
>>  {
>> +	struct acpi_device *dev = data;
>>  	struct input_dev *inputdev;
>>  	int code = KEY_MAX;
>>  
>> @@ -1049,12 +1071,20 @@ static void cmpc_keys_idev_init(struct input_dev *inputdev)
>>  
>>  static int cmpc_keys_add(struct acpi_device *acpi)
>>  {
>> -	return cmpc_add_acpi_notify_device(acpi, "cmpc_keys",
>> -					   cmpc_keys_idev_init);
>> +	int error;
>> +
>> +	error = cmpc_add_acpi_notify_device(acpi, "cmpc_keys",
>> +					    cmpc_keys_idev_init);
>> +	if (error)
>> +		return error;
>> +
>> +	return acpi_device_install_event_handler(acpi, ACPI_DEVICE_NOTIFY,
>> +						 cmpc_keys_handler);
>>  }
>>  
>>  static void cmpc_keys_remove(struct acpi_device *acpi)
>>  {
>> +	acpi_device_remove_event_handler(acpi, ACPI_DEVICE_NOTIFY, cmpc_keys_handler);
>>  	cmpc_remove_acpi_notify_device(acpi);
>>  }
>>  
>> @@ -1071,7 +1101,6 @@ static struct acpi_driver cmpc_keys_acpi_driver = {
>>  	.ops = {
>>  		.add = cmpc_keys_add,
>>  		.remove = cmpc_keys_remove,
>> -		.notify = cmpc_keys_handler,
>>  	}
>>  };
>>  
>> -- 
>> 2.40.1
>>