From e9256e142f597edf90c68cec22db4c4aebaa27de Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Sat, 6 May 2017 11:43:05 +0200 Subject: [PATCH] mmc: pwrseq_simple: Parse DTS for the power-off-delay-us property If the optional power-off-delay-us property is found, insert the corresponding delay after asserting the GPIO during power off. This enables a graceful shutdown sequence for some devices. Cc: linux-mmc@vger.kernel.org Signed-off-by: Ulf Hansson Acked-by: Arnd Bergmann --- drivers/mmc/core/pwrseq_simple.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/mmc/core/pwrseq_simple.c b/drivers/mmc/core/pwrseq_simple.c index 1304160de168..13ef162cf066 100644 --- a/drivers/mmc/core/pwrseq_simple.c +++ b/drivers/mmc/core/pwrseq_simple.c @@ -27,6 +27,7 @@ struct mmc_pwrseq_simple { struct mmc_pwrseq pwrseq; bool clk_enabled; u32 post_power_on_delay_ms; + u32 power_off_delay_us; struct clk *ext_clk; struct gpio_descs *reset_gpios; }; @@ -78,6 +79,10 @@ static void mmc_pwrseq_simple_power_off(struct mmc_host *host) mmc_pwrseq_simple_set_gpios_value(pwrseq, 1); + if (pwrseq->power_off_delay_us) + usleep_range(pwrseq->power_off_delay_us, + 2 * pwrseq->power_off_delay_us); + if (!IS_ERR(pwrseq->ext_clk) && pwrseq->clk_enabled) { clk_disable_unprepare(pwrseq->ext_clk); pwrseq->clk_enabled = false; @@ -119,6 +124,8 @@ static int mmc_pwrseq_simple_probe(struct platform_device *pdev) device_property_read_u32(dev, "post-power-on-delay-ms", &pwrseq->post_power_on_delay_ms); + device_property_read_u32(dev, "power-off-delay-us", + &pwrseq->power_off_delay_us); pwrseq->pwrseq.dev = dev; pwrseq->pwrseq.ops = &mmc_pwrseq_simple_ops; -- 2.30.2