[PATCH 1/2] spi: rockchip: add support for "cs-gpios" dts property

Heiko Stübner heiko at sntech.de
Mon Jun 12 01:36:38 PDT 2017


Am Montag, 12. Juni 2017, 16:26:07 CEST schrieb jeffy:
> Hi Shawn,
> 
> On 06/12/2017 03:15 PM, Shawn Lin wrote:
> > Hi Jeffy,
> > 
> > On 2017/6/12 14:14, Jeffy Chen wrote:
> >> Support using "cs-gpios" property to specify cs gpios.
> >> 
> >> Signed-off-by: Jeffy Chen <jeffy.chen at rock-chips.com>
> >> ---
> >> 
> >>   .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
> >>   drivers/spi/spi-rockchip.c                         | 52
> >> 
> >> ++++++++++++++++++++++
> >> 
> >>   2 files changed, 54 insertions(+)
> >> 
> >> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> index 83da493..02171b2 100644
> >> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> > 
> > The changes for doc should be another patch, and...
> 
> but i saw others didn't separate them:
> cf9e478 spi: sh-msiof: Add slave mode support
> 23e291c spi: rockchip: support "sleep" pin configuration

it sometimes falls through the cracks, but having dt-binding patches
separate is meant to make it easier on DT-Maintainers to find
patches they need to look at.


> >> +    if (!data->cs_gpio_requested) {
> >> +        ret = gpio_request_one(spi->cs_gpio, flags,
> >> +                       dev_name(&spi->dev));
> >> +        if (!ret)
> >> +            data->cs_gpio_requested = 1;
> >> +    } else
> >> +        ret = gpio_direction_output(spi->cs_gpio, flags);
> > 
> > need brace around 'else' statement. Also I don't see data used
> > elsewhere, so you need these code above.
> 
> ok.
> and the cs_gpio_requested is to mark cs_gpio requested, because the
> setup func might be called multiple times, we only need to request gpio
> at the first time.

Aren't the gpiod* functions meant to be used for new things?
Also you might actually do a bit of error handling there, especially 
EPROBE_DEFER.


Heiko



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