Patch "mmc: mmc_spi: Add Card Detect comments and fix CD GPIO case" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

mmc: mmc_spi: Add Card Detect comments and fix CD GPIO case

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
mmc-mmc_spi-add-card-detect-comments-and-fix-cd-gpio-case.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Magnus Damm <[email protected]>
Date: Tue, 16 Feb 2016 13:06:41 +0900
Subject: mmc: mmc_spi: Add Card Detect comments and fix CD GPIO case

From: Magnus Damm <[email protected]>

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.

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

@@ -1436,6 +1436,12 @@ 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);
 	}
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/mmc-mmc_spi-add-card-detect-comments-and-fix-cd-gpio-case.patch