openwrtv3/target/linux/mxs/patches-3.14/130-mxs-mmc-fix-card-detect.patch

67 lines
2.2 KiB
Diff
Raw Normal View History

From 91769986a724f63db52f3c78c79ac84a5b7045bf Mon Sep 17 00:00:00 2001
From: Daniel Willmann <daniel@totalueberwachung.de>
Date: Sat, 19 Apr 2014 23:59:18 +0200
Subject: [PATCH] mmc: mxs: fix card detection function for broken card detect
Return -ENOSYS in get_cd if broken-cd is specified in the device tree.
Commit a91fe279ae75 (mmc: mxs: use standard flag for broken card
detection) sets MMC_CAP_NEEDS_POLL when broken-cd is specified. This
driver sets this flag unconditionally as it does not support a card
detect interrupt. Instead, broken-cd means that there is no card detect
signal connected.
The mmc core checks the get_cd function return value to determine if a
card is present. Only for a non-zero return value it will attempt to
initialize the card. So retuning -ENOSYS will allow the card to be
initialized.
For comparison, mmc_gpio_get_cd in slot-gpio.c also returns -ENOSYS if
the card detect GPIO is not valid.
Signed-off-by: Daniel Willmann <daniel@totalueberwachung.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
---
drivers/mmc/host/mxs-mmc.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/drivers/mmc/host/mxs-mmc.c
+++ b/drivers/mmc/host/mxs-mmc.c
@@ -70,6 +70,7 @@ struct mxs_mmc_host {
unsigned char bus_width;
spinlock_t lock;
int sdio_irq_en;
+ bool broken_cd;
};
static int mxs_mmc_get_cd(struct mmc_host *mmc)
@@ -78,6 +79,9 @@ static int mxs_mmc_get_cd(struct mmc_hos
struct mxs_ssp *ssp = &host->ssp;
int present, ret;
+ if (host->broken_cd)
+ return -ENOSYS;
+
ret = mmc_gpio_get_cd(mmc);
if (ret >= 0)
return ret;
@@ -568,6 +572,7 @@ static int mxs_mmc_probe(struct platform
{
const struct of_device_id *of_id =
of_match_device(mxs_mmc_dt_ids, &pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
struct mxs_mmc_host *host;
struct mmc_host *mmc;
struct resource *iores;
@@ -634,6 +639,8 @@ static int mxs_mmc_probe(struct platform
mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL;
+ host->broken_cd = of_property_read_bool(np, "broken-cd");
+
mmc->f_min = 400000;
mmc->f_max = 288000000;