[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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