From bfd694d5e21c2f0d344db6afeaf993bb0f299545 Mon Sep 17 00:00:00 2001 From: Shawn Lin Date: Tue, 24 Apr 2018 08:42:57 +0800 Subject: [PATCH] mmc: core: Add tunable delay before detecting card after card is inserted Allow to use tunable delay before detecting card after card is inserted, which either comes from firmware node, or comes from debounce value passed on to mmc_gpiod_request_cd(). If the platform doesn't support debounce, then we fall back to use the debounce period as the delay, otherwise, it behaves the same as before that a HW debounce(if set) plus a 200ms hardcode delay before detecting the card. Signed-off-by: Shawn Lin Reviewed-by: Linus Walleij Signed-off-by: Ulf Hansson --- drivers/mmc/core/host.c | 9 +++++++-- drivers/mmc/core/slot-gpio.c | 7 +++++-- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 64b03d6eaf18..da08a17fbf6c 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -179,7 +179,7 @@ static void mmc_retune_timer(struct timer_list *t) int mmc_of_parse(struct mmc_host *host) { struct device *dev = host->parent; - u32 bus_width, drv_type; + u32 bus_width, drv_type, cd_debounce_delay_ms; int ret; bool cd_cap_invert, cd_gpio_invert = false; bool ro_cap_invert, ro_gpio_invert = false; @@ -230,11 +230,16 @@ int mmc_of_parse(struct mmc_host *host) } else { cd_cap_invert = device_property_read_bool(dev, "cd-inverted"); + if (device_property_read_u32(dev, "cd-debounce-delay-ms", + &cd_debounce_delay_ms)) + cd_debounce_delay_ms = 200; + if (device_property_read_bool(dev, "broken-cd")) host->caps |= MMC_CAP_NEEDS_POLL; ret = mmc_gpiod_request_cd(host, "cd", 0, true, - 0, &cd_gpio_invert); + cd_debounce_delay_ms, + &cd_gpio_invert); if (!ret) dev_info(host->parent, "Got CD GPIO\n"); else if (ret != -ENOENT && ret != -ENOSYS) diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c index 31f7dbb15668..56559351d2e1 100644 --- a/drivers/mmc/core/slot-gpio.c +++ b/drivers/mmc/core/slot-gpio.c @@ -28,15 +28,17 @@ struct mmc_gpio { irqreturn_t (*cd_gpio_isr)(int irq, void *dev_id); char *ro_label; char cd_label[0]; + u32 cd_debounce_delay_ms; }; static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id) { /* Schedule a card detection after a debounce timeout */ struct mmc_host *host = dev_id; + struct mmc_gpio *ctx = host->slot.handler_priv; host->trigger_card_event = true; - mmc_detect_change(host, msecs_to_jiffies(200)); + mmc_detect_change(host, msecs_to_jiffies(ctx->cd_debounce_delay_ms)); return IRQ_HANDLED; } @@ -49,6 +51,7 @@ int mmc_gpio_alloc(struct mmc_host *host) if (ctx) { ctx->ro_label = ctx->cd_label + len; + ctx->cd_debounce_delay_ms = 200; snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent)); snprintf(ctx->ro_label, len, "%s ro", dev_name(host->parent)); host->slot.handler_priv = ctx; @@ -261,7 +264,7 @@ int mmc_gpiod_request_cd(struct mmc_host *host, const char *con_id, if (debounce) { ret = gpiod_set_debounce(desc, debounce); if (ret < 0) - return ret; + ctx->cd_debounce_delay_ms = debounce; } if (gpio_invert)