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@xxxxxxxxxx> --- 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 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html