From 721e0497172f0fa661eed2d63367cddf479f35e8 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 7 Aug 2016 21:02:38 +0200 Subject: [PATCH] mmc: pwrseq-simple: Add an optional post-power-on-delay 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 Acked-by: Rob Herring Signed-off-by: Ulf Hansson --- .../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 ce0e76749671..e25436861867 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 450d907c6e6c..1304160de168 100644 --- a/drivers/mmc/core/pwrseq_simple.c +++ b/drivers/mmc/core/pwrseq_simple.c @@ -16,6 +16,8 @@ #include #include #include +#include +#include #include @@ -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; -- 2.20.1