[PATCH resend] mmc: pwrseq-simple: Add an optional post-power-on-delay

Ulf Hansson ulf.hansson at linaro.org
Mon Aug 22 06:38:29 PDT 2016


On 7 August 2016 at 21:02, Hans de Goede <hdegoede at redhat.com> wrote:
> Some devices need a while to boot their firmware after providing clks /
> de-asserting resets before they are ready to receive sdio commands.
>
> This commits adds a post-power-on-delay-ms devicetree property to
> mmc-pwrseq-simple for use with such devices.
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>

Thanks, applied for next!

Kind regards
Uffe

> ---
>  Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt | 2 ++
>  drivers/mmc/core/pwrseq_simple.c                            | 9 +++++++++
>  2 files changed, 11 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
> index ce0e767..e254368 100644
> --- a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
> +++ b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt
> @@ -16,6 +16,8 @@ Optional properties:
>    See ../clocks/clock-bindings.txt for details.
>  - clock-names : Must include the following entry:
>    "ext_clock" (External clock provided to the card).
> +- post-power-on-delay-ms : Delay in ms after powering the card and
> +       de-asserting the reset-gpios (if any)
>
>  Example:
>
> diff --git a/drivers/mmc/core/pwrseq_simple.c b/drivers/mmc/core/pwrseq_simple.c
> index 450d907..1304160 100644
> --- a/drivers/mmc/core/pwrseq_simple.c
> +++ b/drivers/mmc/core/pwrseq_simple.c
> @@ -16,6 +16,8 @@
>  #include <linux/device.h>
>  #include <linux/err.h>
>  #include <linux/gpio/consumer.h>
> +#include <linux/delay.h>
> +#include <linux/property.h>
>
>  #include <linux/mmc/host.h>
>
> @@ -24,6 +26,7 @@
>  struct mmc_pwrseq_simple {
>         struct mmc_pwrseq pwrseq;
>         bool clk_enabled;
> +       u32 post_power_on_delay_ms;
>         struct clk *ext_clk;
>         struct gpio_descs *reset_gpios;
>  };
> @@ -64,6 +67,9 @@ static void mmc_pwrseq_simple_post_power_on(struct mmc_host *host)
>         struct mmc_pwrseq_simple *pwrseq = to_pwrseq_simple(host->pwrseq);
>
>         mmc_pwrseq_simple_set_gpios_value(pwrseq, 0);
> +
> +       if (pwrseq->post_power_on_delay_ms)
> +               msleep(pwrseq->post_power_on_delay_ms);
>  }
>
>  static void mmc_pwrseq_simple_power_off(struct mmc_host *host)
> @@ -111,6 +117,9 @@ static int mmc_pwrseq_simple_probe(struct platform_device *pdev)
>                 return PTR_ERR(pwrseq->reset_gpios);
>         }
>
> +       device_property_read_u32(dev, "post-power-on-delay-ms",
> +                                &pwrseq->post_power_on_delay_ms);
> +
>         pwrseq->pwrseq.dev = dev;
>         pwrseq->pwrseq.ops = &mmc_pwrseq_simple_ops;
>         pwrseq->pwrseq.owner = THIS_MODULE;
> --
> 2.7.4
>



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