[PATCH 4.5 190/238] mmc: mmc_spi: Add Card Detect comments and fix CD GPIO case

From: Greg Kroah-Hartman
Date: Sun Apr 10 2016 - 14:53:16 EST


4.5-stable review patch. If anyone has any objections, please let me know.

------------------

From: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>

commit bcdc9f260bdce09913db1464be9817170d51044a upstream.

This patch fixes the MMC SPI driver from doing polling card detect when a
CD GPIO that supports interrupts is specified using the gpios DT property.

Without this patch the DT node below results in the following output:

spi_gpio: spi-gpio { /* SD2 @ CN12 */
compatible = "spi-gpio";
#address-cells = <1>;
#size-cells = <0>;
gpio-sck = <&gpio6 16 GPIO_ACTIVE_HIGH>;
gpio-mosi = <&gpio6 17 GPIO_ACTIVE_HIGH>;
gpio-miso = <&gpio6 18 GPIO_ACTIVE_HIGH>;
num-chipselects = <1>;
cs-gpios = <&gpio6 21 GPIO_ACTIVE_LOW>;
status = "okay";

spi@0 {
compatible = "mmc-spi-slot";
reg = <0>;
voltage-ranges = <3200 3400>;
spi-max-frequency = <25000000>;
gpios = <&gpio6 22 GPIO_ACTIVE_LOW>; /* CD */
};
};

# dmesg | grep mmc
mmc_spi spi32766.0: SD/MMC host mmc0, no WP, no poweroff, cd polling
mmc0: host does not support reading read-only switch, assuming write-enable
mmc0: new SDHC card on SPI
mmcblk0: mmc0:0000 SU04G 3.69 GiB
mmcblk0: p1

With this patch applied the "cd polling" portion above disappears.

Signed-off-by: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/mmc_spi.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -1442,6 +1442,12 @@ static int mmc_spi_probe(struct spi_devi
host->pdata->cd_debounce);
if (status != 0)
goto fail_add_host;
+
+ /* The platform has a CD GPIO signal that may support
+ * interrupts, so let mmc_gpiod_request_cd_irq() decide
+ * if polling is needed or not.
+ */
+ mmc->caps &= ~MMC_CAP_NEEDS_POLL;
mmc_gpiod_request_cd_irq(mmc);
}