From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Shawn Lin Subject: [PATCH v4 2/2] mmc: core: Add tunable delay before detecting card after card is inserted Date: Tue, 24 Apr 2018 08:42:57 +0800 Message-Id: <1524530577-183915-2-git-send-email-shawn.lin@rock-chips.com> In-Reply-To: <1524530577-183915-1-git-send-email-shawn.lin@rock-chips.com> References: <1524530577-183915-1-git-send-email-shawn.lin@rock-chips.com> To: Ulf Hansson Cc: Rob Herring , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, Shawn Lin List-ID: 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 --- Changes in v4: None Changes in v3: - rename to cd_debounce_delay_ms Changes in v2: - doesn't introduce new agrument for mmc_gpiod_request_cd and drop the change for host drivers 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 64b03d6..da08a17 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 31f7dbb..5655935 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) -- 1.9.1