Messages in this thread | | | Date | Wed, 10 Feb 2016 16:29:46 +0200 | Subject | Re: [PATCH v2] gpio: Add driver for TI TPIC2810 | From | Andy Shevchenko <> |
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On Wed, Feb 10, 2016 at 4:21 PM, Linus Walleij <linus.walleij@linaro.org> wrote: > On Sun, Jan 31, 2016 at 11:52 PM, Andy Shevchenko > <andy.shevchenko@gmail.com> wrote: > >> It reminds me how 12 channel PWM chip is used on Intel Galileo Gen 2. >> Half pins are PWM, the other half is GPIO used for discrete based pin >> muxing and control. Nevertheless I think it's a userspace issue for >> now, otherwise we have to provide some 'semi-virtual' way of >> presenting pins as GPIO lines. > > That sounds like an MFD spawning a GPIO and a PWM cell. > That it is called "a PWM chip" is no big deal, it should be > modeled according to what it is, not what it claims to be.
Although I agree with model I barely imagine how in this case drivers should access PWM chip registers in non-race way (take into account that PWM itself is connected to i2c bus).
> (Which makes me wanna merge this present patch as a GPIO > driver since it claims to be a LED driver but is a GPO.) > > See the ST Multipurpose Expander for an example > drivers/mfd/stmpe.c > drivers/gpio/gpio-stmpe.c > drivers/input/keyboard/stmpe-keypad.c
I will look to the example later, thanks.
-- With Best Regards, Andy Shevchenko
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