[U-Boot] [PATCH v3 1/9] dm: pinctrl: Add get_pin_muxing() ops

[Patrice CHOTARD]

Hi Simon

On 10/19/18 5:28 AM, Simon Glass wrote:
> Hi Patrice,
> 
> On 9 October 2018 at 07:31, Patrice Chotard <patrice.chotard at st.com> wrote:
>> Add get_pin_muxing() which allows to display the muxing
>> of a given pin belonging to a pin-controller.
>>
>> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
>> ---
>>
>> Changes in v3:
>>  - Replace const char **buf parameter by char *buf, int size parameters
>>    for pinctrl_get_pin_muxing()
>>
>> Changes in v2:
>>  - Replace pinmux_show ops which displayed the complete pin-controller
>>    muxing by get_pin_muxing ops which displays the muxing of one pin
>>
>>  drivers/pinctrl/pinctrl-uclass.c | 13 +++++++++++++
>>  include/dm/pinctrl.h             | 32 ++++++++++++++++++++++++++++++++
>>  2 files changed, 45 insertions(+)
> 
> Reviewed-by: Simon Glass <sjg at chromium.org>
> 
> But please see below.
> 
>>
>> diff --git a/drivers/pinctrl/pinctrl-uclass.c b/drivers/pinctrl/pinctrl-uclass.c
>> index c38bb212ed74..cd2ca4e4950e 100644
>> --- a/drivers/pinctrl/pinctrl-uclass.c
>> +++ b/drivers/pinctrl/pinctrl-uclass.c
>> @@ -249,6 +249,19 @@ int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index)
>>         return ops->get_gpio_mux(dev, banknum, index);
>>  }
>>
>> +int pinctrl_get_pin_muxing(struct udevice *dev, int selector, char *buf,
>> +                          int size)
>> +{
>> +       struct pinctrl_ops *ops = pinctrl_get_ops(dev);
>> +
>> +       if (!ops->get_pin_muxing)
>> +               return -ENOSYS;
>> +
>> +       snprintf(buf, size, ops->get_pin_muxing(dev, selector));
> 
> I wonder if it would be easy to return -ENOSPC if the string is too long?

Not so easy, for example in pinctrl_stm32.c, depending of the pin's
muxing mode, i not only copy but also, in some case, concatenate
additional information. It would complexify the pinctrl code.


Patrice

> 
> Regards,
> Simon
>