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 <shawn.lin@xxxxxxxxxxxxxx>
---
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 | 7 +++++--
drivers/mmc/core/slot-gpio.c | 9 +++++++--
2 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 64b03d6..d281cbf 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_delay_ms;
int ret;
bool cd_cap_invert, cd_gpio_invert = false;
bool ro_cap_invert, ro_gpio_invert = false;
@@ -230,11 +230,14 @@ 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-delay-ms", &cd_delay_ms))
+ cd_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_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..2ef41be 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_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_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_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;
@@ -239,6 +242,8 @@ int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio,
* @debounce: debounce time in microseconds
* @gpio_invert: will return whether the GPIO line is inverted or not, set
* to NULL to ignore
+ * @cd_delay_ms: delay time in ms before detecting card after card insert
+ * event
*
* Use this function in place of mmc_gpio_request_cd() to use the GPIO
* descriptor API. Note that it must be called prior to mmc_add_host()
@@ -261,7 +266,7 @@ 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_delay_ms = debounce;
}
if (gpio_invert)
--
1.9.1
--
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