Re: [PATCH v13 2/9] mfd: qcom-spmi-pmic: expose the PMIC revid information to clients

[Caleb Connolly <caleb.connolly@linaro.org>]

On 29/04/2022 11:06, Lee Jones wrote:
> On Thu, 28 Apr 2022, Caleb Connolly wrote:
>> On 28/04/2022 17:14, Lee Jones wrote:
>>> On Wed, 27 Apr 2022, Caleb Connolly wrote:
>>>> On 25/04/2022 16:03, Lee Jones wrote:
>>>>>
>>>>> On Wed, 23 Mar 2022, Caleb Connolly wrote:
>>>>>> From: Caleb Connolly <caleb.connolly@linaro.org>
>>>>>>
>>>>>> Some PMIC functions such as the RRADC need to be aware of the PMIC
>>>>>> chip revision information to implement errata or otherwise adjust
>>>>>> behaviour, export the PMIC information to enable this.
>>>>>>
>>>>>> This is specifically required to enable the RRADC to adjust
>>>>>> coefficients based on which chip fab the PMIC was produced in,
>>>>>> this can vary per unique device and therefore has to be read at
>>>>>> runtime.
>>>>>>
>>>>>> Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
>>>>>> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>>>> Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>>>> ---
>>>>>>     drivers/mfd/qcom-spmi-pmic.c      | 261 +++++++++++++++++++-----------
>>>>>>     include/soc/qcom/qcom-spmi-pmic.h |  60 +++++++
>>>>>>     2 files changed, 231 insertions(+), 90 deletions(-)
>>>>>>     create mode 100644 include/soc/qcom/qcom-spmi-pmic.h
>>>
>>> [...]
>>>
>>>>>> +			/*
>>>>>> +			 * If the base USID for this PMIC hasn't probed yet
>>>>>> +			 * but the secondary USID has, then we need to defer
>>>>>> +			 * the function driver so that it will attempt to
>>>>>> +			 * probe again when the base USID is ready.
>>>>>> +			 */
>>>>>> +			if (pmic_addr == function_parent_usid  - (ctx->num_usids - 1))
>>>>>
>>>>> Double "  ".
>>>> Ack
>>>>>
>>>>> Over-bracketing of statements with matching operands.
>>>> I don't think x - (y - 1) is equal to x - y - 1? Or am I misunderstanding you here?
>>>
>>> Can you give me an example when this would be the case?
>> According to the Python interpreter:
>>>>> x=7
>>>>> y=4
>>>>> x - y - 1
>> 2
>>>>> x - (y - 1)
>> 4
>>
>> C does also respect the first rule of BODMAS - parenthesis are always
>> evaluated first.
> 
> Fair point, well presented.
> 
> Thanks for this - I understand the problem now.
Thanks,

Could you respond to my other two points in 
https://lore.kernel.org/linux-arm-msm/2763f103-6947-e431-cef5-e202c324d678@linaro.org/

Regarding

if (!of_match_device(pmic_spmi_id_table, dev))

and

ctx->num_usids = (long)of_device_get_match_data(&sdev->dev);
> 

-- 
Kind Regards,
Caleb (they/he)