Re: [PATCH] hwmon: (dell-smm-hwmon) Fix index values

[Guenter Roeck <linux@roeck-us.net>]

On 5/13/21 9:48 AM, Pali Rohár wrote:
> On Thursday 13 May 2021 17:45:46 W_Armin@gmx.de wrote:
>> From: Armin Wolf <W_Armin@gmx.de>
>>
>> When support for up to 10 temp sensors and for disabling automatic BIOS
>> fan control was added, noone updated the index values used for
>> disallowing fan support and fan type calls.
>> Fix those values.
> 
> Do you mean this change, right?
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1bb46a20e73b0bb3364cff3839c9f716ed327770
> 
> Yes, it looks like that it should have been part of that change.
> 
> Therefore I suggest to add Fixes tag:
> 
> Fixes: 1bb46a20e73b ("hwmon: (dell-smm) Support up to 10 temp sensors")
> 
> Otherwise looks good!
> 
> Reviewed-by: Pali Rohár <pali@kernel.org>
> 
> For future development I would suggest to rewrite/drop these magic
> numbers as same problem can be easily repeated in future.
> 

The best solution would be to rewrite the driver to use
hwmon_device_register_with_info(), but that should be done
by someone with access to the hardware.

Guenter

>> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
>> ---
>> Tested on a Dell Latitude C600.
>> ---
>>   drivers/hwmon/dell-smm-hwmon.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
>> index 2970892bed82..f2221ca0aa7b 100644
>> --- a/drivers/hwmon/dell-smm-hwmon.c
>> +++ b/drivers/hwmon/dell-smm-hwmon.c
>> @@ -838,10 +838,10 @@ static struct attribute *i8k_attrs[] = {
>>   static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
>>   			      int index)
>>   {
>> -	if (disallow_fan_support && index >= 8)
>> +	if (disallow_fan_support && index >= 20)
>>   		return 0;
>>   	if (disallow_fan_type_call &&
>> -	    (index == 9 || index == 12 || index == 15))
>> +	    (index == 21 || index == 25 || index == 28))
>>   		return 0;
>>   	if (index >= 0 && index <= 1 &&
>>   	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
>> --
>> 2.20.1
>>