Re: [PATCH v2] thermal: Add QPNP PMIC temperature alarm driver

[Kiran Padwal <kiran.padwal@smartplayin.com>]

On Tuesday 30 September 2014 01:06 PM, Ivan T. Ivanov wrote:
> On Tue, 2014-09-30 at 10:00 +0530, Kiran Padwal wrote:
>> On Monday 29 September 2014 07:24 PM, Ivan T. Ivanov wrote:
>>> On Fri, 2014-09-26 at 16:51 +0530, Kiran Padwal wrote:
>>>> On Thursday 25 September 2014 07:00 PM, Ivan T. Ivanov wrote:
>>>>> Add support for the temperature alarm peripheral found inside
>>>>> Qualcomm plug-and-play (QPNP) PMIC chips.  The temperature alarm
>>>>> peripheral outputs a pulse on an interrupt line whenever the
>>>>> thermal over temperature stage value changes.  Implement an ISR
>>>>> to manage this interrupt.
>>>>>
>>>>
>>>> <snip>
>>>>
>>>>> + * This function updates the internal temp value based on the
>>>>> + * current thermal stage and threshold as well as the previous stage
>>>>> + */
>>>>> +static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
>>>>> +{
>>>>> +	unsigned int stage;
>>>>> +	int rc;
>>>>> +	u8 reg;
>>>>> +
>>>>> +	rc = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
>>>>> +	if (rc < 0)
>>>>> +		return rc;
>>>>> +
>>>>> +	stage = reg & STATUS_STAGE_MASK;
>>>>
>>>> During compilation, getting a waring as below,
>>>>
>>>> drivers/thermal/qpnp-temp-alarm.c: In function ‘qpnp_tm_update_temp_no_adc’:
>>>> drivers/thermal/qpnp-temp-alarm.c:135:8: warning: ‘reg’ may be used uninitialized in this function [-Wmaybe-uninitialized]
>>>>   stage = reg & STATUS_STAGE_MASK;
>>>
>>> Could you share compiler version and options which you are using.
>>> I am unable to trigger this warning. Looking code I can not 
>>> see how this could happen.
>>
>> I have Linaro cross tool chain with version-4.8.3 and I am simply doing "make zImage" without any option.
> 
> Hm, no warnings with arm-unknown-linux-gnueabi-gcc (GCC) 4.6.3 and
> arm-linux-gnueabihf-gcc (crosstool-NG linaro-1.13.1-4.9-2014.09, but
> indeed arm-linux-gnueabihf-gcc (crosstool-NG linaro-1.13.1-4.8-2014.03.
> 
> I will say that this is false positive :-). Please update your tool-chain.
> 

Thanks to verify, I will do that.

Thanks,
--Kiran