Re: [PATCH v1 01/15] ACPI: platform_profile: Add support for notification chains

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 7/12/22 17:03, Limonciello, Mario wrote:
> [Public]
> 
>> -----Original Message-----
>> From: S-k, Shyam-sundar <Shyam-sundar.S-k@amd.com>
>> Sent: Tuesday, July 12, 2022 09:59
>> To: hdegoede@redhat.com; markgross@kernel.org
>> Cc: platform-driver-x86@vger.kernel.org; Patil Rajesh
>> <Patil.Reddy@amd.com>; Limonciello, Mario
>> <Mario.Limonciello@amd.com>; S-k, Shyam-sundar <Shyam-sundar.S-
>> k@amd.com>
>> Subject: [PATCH v1 01/15] ACPI: platform_profile: Add support for
>> notification chains
>>
>> From: Mario Limonciello <mario.limonciello@amd.com>
>>
>> Allow other drivers to react to determine current active profile
>> and react to platform profile changes.
>>
> 
> The original patch this came from had notification chains, but as this was
> pared down to just export the get method, this commit message and title
> should be updated.
> 
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
>> ---
>>  drivers/acpi/platform_profile.c  | 26 ++++++++++++++++++++++++++
>>  include/linux/platform_profile.h |  1 +
>>  2 files changed, 27 insertions(+)
>>
>> diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
>> index d418462ab791..7e12a1f30f06 100644
>> --- a/drivers/acpi/platform_profile.c
>> +++ b/drivers/acpi/platform_profile.c
>> @@ -49,6 +49,32 @@ static ssize_t platform_profile_choices_show(struct
>> device *dev,
>>  	return len;
>>  }
>>
>> +int platform_profile_get(enum platform_profile_option *profile)
>> +{
>> +	int err;
>> +
>> +	err = mutex_lock_interruptible(&profile_lock);

Besides Mario'r remark about the commit message, this must be
mutex_lock() not mutex_lock_interruptible() since this function
is intended to be called by other kernel code, rather then from
userspace.

Regards,

Hans


>> +	if (err)
>> +		return err;
>> +
>> +	if (!cur_profile) {
>> +		mutex_unlock(&profile_lock);
>> +		return -ENODEV;
>> +	}
>> +
>> +	err = cur_profile->profile_get(cur_profile, profile);
>> +	mutex_unlock(&profile_lock);
>> +	if (err)
>> +		return err;
>> +
>> +	/* Check that profile is valid index */
>> +	if (WARN_ON((*profile < 0) || (*profile >=
>> ARRAY_SIZE(profile_names))))
>> +		return -EIO;
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(platform_profile_get);
>> +
>>  static ssize_t platform_profile_show(struct device *dev,
>>  					struct device_attribute *attr,
>>  					char *buf)
>> diff --git a/include/linux/platform_profile.h
>> b/include/linux/platform_profile.h
>> index e5cbb6841f3a..2395be670dfd 100644
>> --- a/include/linux/platform_profile.h
>> +++ b/include/linux/platform_profile.h
>> @@ -37,5 +37,6 @@ struct platform_profile_handler {
>>  int platform_profile_register(struct platform_profile_handler *pprof);
>>  int platform_profile_remove(void);
>>  void platform_profile_notify(void);
>> +int platform_profile_get(enum platform_profile_option *profile);
>>
>>  #endif  /*_PLATFORM_PROFILE_H_*/
>> --
>> 2.25.1
>