Re: [PATCH 1/2] i2c-mux-gpio: test if the gpio can sleep

From: Lars-Peter Clausen
Date: Thu Oct 10 2013 - 04:44:54 EST


On 10/10/2013 10:39 AM, Ionut Nicu wrote:
> Some gpio chips may have get/set operations that
> can sleep. For this type of chips we must use the
> _cansleep() version of gpio_set_value.
>
> Signed-off-by: Ionut Nicu <ioan.nicu.ext@xxxxxxx>
> ---
> drivers/i2c/muxes/i2c-mux-gpio.c | 11 ++++++++---
> 1 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
> index a764da7..b5f17ef 100644
> --- a/drivers/i2c/muxes/i2c-mux-gpio.c
> +++ b/drivers/i2c/muxes/i2c-mux-gpio.c
> @@ -27,11 +27,16 @@ struct gpiomux {
>
> static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
> {
> + unsigned gpio;
> int i;
>
> - for (i = 0; i < mux->data.n_gpios; i++)
> - gpio_set_value(mux->gpio_base + mux->data.gpios[i],
> - val & (1 << i));
> + for (i = 0; i < mux->data.n_gpios; i++) {
> + gpio = mux->gpio_base + mux->data.gpios[i];
> + if (gpio_cansleep(gpio))
> + gpio_set_value_cansleep(gpio, val & (1 << i));
> + else
> + gpio_set_value(gpio, val & (1 << i));

The proper way to do this is just always use the _cansleep() version.
gpio_set_value() only works for chips which do not sleep,
gpio_set_value_cansleep() works for both those who do sleep and those who do
not.

> + }
> }
>
> static int i2c_mux_gpio_select(struct i2c_adapter *adap, void *data, u32 chan)
>

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