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author | Hans de Goede <hdegoede@redhat.com> | 2016-08-07 21:02:38 +0200 |
---|---|---|
committer | Ulf Hansson <ulf.hansson@linaro.org> | 2016-09-26 21:31:07 +0200 |
commit | 721e0497172f0fa661eed2d63367cddf479f35e8 (patch) | |
tree | 4f7649316618c2eb0f91dc74b6e59f808417fb0d | |
parent | 4cbc6dbd52516363c61ad8f116355ad63fe9cdf2 (diff) | |
download | linux-721e0497172f0fa661eed2d63367cddf479f35e8.tar.gz linux-721e0497172f0fa661eed2d63367cddf479f35e8.tar.bz2 linux-721e0497172f0fa661eed2d63367cddf479f35e8.zip |
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 <hdegoede@redhat.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-rw-r--r-- | Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt | 2 | ||||
-rw-r--r-- | drivers/mmc/core/pwrseq_simple.c | 9 |
2 files changed, 11 insertions, 0 deletions
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 <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; |