mmc: msm_sdcc: Add support for card detect, write protect gpios

Add support for SD card insertion/removal detection and
write protect switch detection using gpio numbers passed
through device tree.

Change-Id: I63aed72f38f912b33de4b8eaedf72e52bbaeb4a0
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>

Documentation/devicetree/bindings/mmc/msm_sdcc.txt

@@ -16,10 +16,8 @@ Required properties:
 Optional Properties:
 	- cell-index - defines slot ID.
 	- qcom,sdcc-bus-width - defines the bus I/O width that controller supports.
-	- qcom,sdcc-wp-gpio - defines write protect switch gpio.
-	- qcom,sdcc-wp-polarity - specifies the polarity of wp switch.
-	- qcom,sdcc-cd-gpio - defines card detect gpio number.
-	- qcom,sdcc-cd-polarity - specifies the polarity of cd gpio.
+	- wp-gpios - specify GPIO for write protect switch detection.
+	- cd-gpios - specify GPIO for card detection.
 	- qcom,sdcc-nonremovable - specifies whether the card in slot is
 				hot pluggable or hard wired.
 	- qcom,sdcc-disable_cmd23 - disable sending CMD23 to card when controller can't support it.

arch/arm/include/asm/mach/mmc.h

@@ -146,7 +146,7 @@ struct mmc_platform_data {
 	unsigned int uhs_caps2;
 	void (*sdio_lpm_gpio_setup)(struct device *, unsigned int);
         unsigned int status_irq;
-	unsigned int status_gpio;
+	int status_gpio;
 	/* Indicates the polarity of the GPIO line when card is inserted */
 	bool is_status_gpio_active_low;
         unsigned int sdiowakeup_irq;
@@ -158,7 +158,7 @@ struct mmc_platform_data {
 	unsigned int msmsdcc_fmax;
 	bool nonremovable;
 	unsigned int mpm_sdiowakeup_int;
-	unsigned int wpswitch_gpio;
+	int wpswitch_gpio;
 	bool is_wpswitch_active_low;
 	struct msm_mmc_slot_reg_data *vreg_data;
 	int is_sdio_al_client;

drivers/mmc/host/msm_sdcc.c

@@ -3165,7 +3165,7 @@ static int msmsdcc_get_ro(struct mmc_host *mmc)
 
 	if (host->plat->wpswitch) {
 		status = host->plat->wpswitch(mmc_dev(mmc));
-	} else if (host->plat->wpswitch_gpio) {
+	} else if (gpio_is_valid(host->plat->wpswitch_gpio)) {
 		status = gpio_request(host->plat->wpswitch_gpio,
 					"SD_WP_Switch");
 		if (status) {
@@ -3971,7 +3971,7 @@ msmsdcc_check_status(unsigned long data)
 	struct msmsdcc_host *host = (struct msmsdcc_host *)data;
 	unsigned int status;
 
-	if (host->plat->status || host->plat->status_gpio) {
+	if (host->plat->status || gpio_is_valid(host->plat->status_gpio)) {
 		if (host->plat->status)
 			status = host->plat->status(mmc_dev(host->mmc));
 		else
@@ -5008,6 +5008,25 @@ err:
 	return ret;
 }
 
+static void msmsdcc_dt_get_cd_wp_gpio(struct device *dev,
+		struct mmc_platform_data *pdata)
+{
+	enum of_gpio_flags flags = OF_GPIO_ACTIVE_LOW;
+	struct device_node *np = dev->of_node;
+
+	pdata->status_gpio = of_get_named_gpio_flags(np,
+			"cd-gpios", 0, &flags);
+	if (gpio_is_valid(pdata->status_gpio)) {
+		pdata->status_irq = gpio_to_irq(pdata->status_gpio);
+		pdata->is_status_gpio_active_low = flags & OF_GPIO_ACTIVE_LOW;
+	}
+
+	pdata->wpswitch_gpio = of_get_named_gpio_flags(np,
+			"wp-gpios", 0, &flags);
+	if (gpio_is_valid(pdata->wpswitch_gpio))
+		pdata->is_wpswitch_active_low = flags & OF_GPIO_ACTIVE_LOW;
+}
+
 static int msmsdcc_dt_parse_gpio_info(struct device *dev,
 		struct mmc_platform_data *pdata)
 {
@@ -5015,6 +5034,8 @@ static int msmsdcc_dt_parse_gpio_info(struct device *dev,
 	struct msm_mmc_pin_data *pin_data;
 	struct device_node *np = dev->of_node;
 
+	msmsdcc_dt_get_cd_wp_gpio(dev, pdata);
+
 	pin_data = devm_kzalloc(dev, sizeof(*pin_data), GFP_KERNEL);
 	if (!pin_data) {
 		dev_err(dev, "No memory for pin_data\n");
@@ -5656,7 +5677,12 @@ msmsdcc_probe(struct platform_device *pdev)
 	 * Setup card detect change
 	 */
 
-	if (plat->status || plat->status_gpio) {
+	if (!plat->status_gpio)
+		plat->status_gpio = -ENOENT;
+	if (!plat->wpswitch_gpio)
+		plat->wpswitch_gpio = -ENOENT;
+
+	if (plat->status || gpio_is_valid(plat->status_gpio)) {
 		if (plat->status)
 			host->oldstat = plat->status(mmc_dev(host->mmc));
 		else