ARM: arch-shmobile: support SDHI card detection on mackerel, using a GPIO

On sh7372 the card-detection pin of SDHI0 can also produce interrupts,
when configured as GPIO. Use this feature to power down SDHI0, when no
card is plugged in.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/arm/mach-shmobile/board-mackerel.c

@@ -39,6 +39,7 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/physmap.h>
+#include <linux/pm_runtime.h>
 #include <linux/smsc911x.h>
 #include <linux/sh_intc.h>
 #include <linux/tca6416_keypad.h>
@@ -913,6 +914,17 @@ static int slot_cn7_get_cd(struct platform_device *pdev)
 }
 
 /* SDHI0 */
+static irqreturn_t mackerel_sdhi0_gpio_cd(int irq, void *arg)
+{
+	struct device *dev = arg;
+	struct sh_mobile_sdhi_info *info = dev->platform_data;
+	struct tmio_mmc_data *pdata = info->pdata;
+
+	tmio_mmc_cd_wakeup(pdata);
+
+	return IRQ_HANDLED;
+}
+
 static struct sh_mobile_sdhi_info sdhi0_info = {
 	.dma_slave_tx	= SHDMA_SLAVE_SDHI0_TX,
 	.dma_slave_rx	= SHDMA_SLAVE_SDHI0_RX,
@@ -1296,6 +1308,7 @@ static void __init mackerel_init(void)
 {
 	u32 srcr4;
 	struct clk *clk;
+	int ret;
 
 	sh7372_pinmux_init();
 
@@ -1401,6 +1414,13 @@ static void __init mackerel_init(void)
 	gpio_request(GPIO_FN_SDHID0_1, NULL);
 	gpio_request(GPIO_FN_SDHID0_0, NULL);
 
+	ret = request_irq(evt2irq(0x3340), mackerel_sdhi0_gpio_cd,
+			  IRQF_TRIGGER_FALLING, "sdhi0 cd", &sdhi0_device.dev);
+	if (!ret)
+		sdhi0_info.tmio_flags |= TMIO_MMC_HAS_COLD_CD;
+	else
+		pr_err("Cannot get IRQ #%d: %d\n", evt2irq(0x3340), ret);
+
 #if !defined(CONFIG_MMC_SH_MMCIF) && !defined(CONFIG_MMC_SH_MMCIF_MODULE)
 	/* enable SDHI1 */
 	gpio_request(GPIO_FN_SDHICMD1, NULL);