[PATCH v2 1/5] pinctrl: qcom: Add ipq8074 pinctrl driver

[varada@codeaurora.org (Varadarajan Narayanan)]

On 5/15/2017 2:35 PM, Varadarajan Narayanan wrote:
> On 5/14/2017 9:53 AM, Bjorn Andersson wrote:
>> On Thu 11 May 03:33 PDT 2017, Varadarajan Narayanan wrote:
>>
>>> On 5/11/2017 4:13 AM, Bjorn Andersson wrote:
>>>> On Thu 04 May 04:53 PDT 2017, Varadarajan Narayanan wrote:
>>>>
>> [..]
>>>>> +enum ipq8074_functions {
>>>>
>>>> Please keep these sorted alphabetically.
>>>
>>> Ok
>>>
>>>>> +    msm_mux_gpio,
>>>>> +    msm_mux_qpic_pad,
>>>>> +    msm_mux_blsp5_i2c,
>>>>> +    msm_mux_blsp5_spi,
>>>>> +    msm_mux_wci20,
>>>>
>>>> What does "20" mean here?
>>>
>>> This is for Wireless Coex Interface. The same functionality can be 
>>> muxed on
>>> to different GPIOs. WCI2, is the 2nd edition of the WCI standard and 
>>> 0, 1
>>> are for the muxing to different GPIOs (alternate muxes).
>>>
>>
>> In other Qualcomm platforms the alternative muxes are denoted by letters
>> (a,b,c...). Would you mind picking up this naming scheme, or do you see
>> any problems with that? (E.g. wci2a in this case)
> 
> Ok
> 
>> Btw, do you need any additional configuration for selecting alternative
>> muxing or is that automagical these days?
> 
> No additional configuration is needed.
> 
>>>>> +    msm_mux_blsp3_spi3,
>>>>> +    msm_mux_burn0,
>>>>> +    msm_mux_pcm_zsi0,
>>>>> +    msm_mux_blsp5_uart,
>>>>> +    msm_mux_mac12,
>>>>
>>>> What does "12" mean here?
>>>
>>> The SoC has three MAC cores. Each core has two pins for the smart 
>>> antenna
>>> feature. macXY indicates the function select for MAC no. X and smart 
>>> antenna
>>> no. Y.
>>>
>>
>> Ok
>>
>>>>> +    msm_mux_blsp3_spi0,
>>>>> +    msm_mux_burn1,
>>>>> +    msm_mux_mac01,
>>>>> +    msm_mux_qdss_cti_trig_out_b0,
>>>>> +    msm_mux_qdss_cti_trig_in_b0,
>>>>> +    msm_mux_qpic_pad4,
>>>>
>>>> What are qpic_pad and qpic_pad0 through qpic_pad8? Different functions,
>>>> alternative muxings...?
>>>
>>> This is for the NAND and LCD display. The pins listed are the 9 data 
>>> pins.
>>>
>>
>> Then you can describe them all as "qpic_pad" (or simply "qpic"?). (It's
>> possible to reference a partial group in the DTS, if that's necessary)
> 
> There are two sets of 9 pins, either of which can go to NAND or LCD.
> Will rename qpic_pad as qpic_a and qpic_pad[0-8] as qpic_b.
> Is that ok?
> 
>>>>> +    msm_mux_blsp4_uart0,
>>>>> +    msm_mux_blsp4_i2c0,
>>>>> +    msm_mux_blsp4_spi0,
>>>>> +    msm_mux_mac21,
>>>>> +    msm_mux_qdss_cti_trig_out_b1,
>>>>> +    msm_mux_qpic_pad5,
>>>>> +    msm_mux_qdss_cti_trig_in_b1,
>>>>> +    msm_mux_qpic_pad6,
>>>>> +    msm_mux_qpic_pad7,
>>>>> +    msm_mux_cxc0,
>>>>> +    msm_mux_mac13,
>>>>> +    msm_mux_qdss_cti_trig_in_a1,
>>>>> +    msm_mux_qdss_cti_trig_out_a1,
>>>>> +    msm_mux_wci22,
>>>>> +    msm_mux_qdss_cti_trig_in_a0,
>>>>> +    msm_mux_qpic_pad1,
>>>>> +    msm_mux_qdss_cti_trig_out_a0,
>>>>> +    msm_mux_qpic_pad2,
>>>>> +    msm_mux_qpic_pad3,
>>>>> +    msm_mux_qdss_traceclk_b,
>>>>> +    msm_mux_qpic_pad0,
>>>>> +    msm_mux_qdss_tracectl_b,
>>>>> +    msm_mux_qpic_pad8,
>>>>> +    msm_mux_pcm_zsi1,
>>>>> +    msm_mux_qdss_tracedata_b,
>>>>> +    msm_mux_led0,
>>>>> +    msm_mux_pwm04,
>>>>
>>>> What does "04" mean here?
>>>
>>> There are 4 Pulse Width Modulation channels, pwmXY is pwm channel X 
>>> and pin
>>> Y.
>>
>> So Y is alternative mux? Can we use letters for this as well?
> 
> Ok

Sorry, actually they are not alternative muxes. There are 4 different 
PWM instances. Each PWM instance can handle 'n' different GPIOs (for 
example, that can be connected to LED etc.).

Thanks
Varada

>>>>> +    msm_mux_led1,
>>>>> +    msm_mux_pwm14,
>>>>> +    msm_mux_led2,
>>>>> +    msm_mux_pwm24,
>>>>> +    msm_mux_pwm00,
>>>>> +    msm_mux_blsp4_uart1,
>>>>
>>>> Are uart0 vs uart1 alternative muxes?
>>>
>>> These are two different uarts available at two independent pins.
>>>
>>
>> Ok, then I'm happy with the naming of this :)
>>
>> Thanks,
>> Bjorn
>>
> 
> Thanks
> Varada

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