mfd: Adding twl6030 mmc card detect support for MMC1

Adding card detect callback function and card detect configuration
function for MMC1 Controller on OMAP4.

Card detect configuration function does initial configuration of the
MMC Control & PullUp-PullDown registers of Phoenix.

For MMC1 Controller, card detect interrupt source is
twl6030 which is non-gpio. The card detect call back function provides
card present/absent status by reading MMC Control register present
on twl6030.

Since OMAP4 doesn't use any GPIO line as used in OMAP3 for card detect,
the suspend/resume initialization which was done in omap_hsmmc_gpio_init
previously is moved to the probe thus making it generic for both OMAP3 &
OMAP4.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/drivers/mfd/twl6030-irq.c b/drivers/mfd/twl6030-irq.c
index 10bf228..2d3bb82 100644
--- a/drivers/mfd/twl6030-irq.c
+++ b/drivers/mfd/twl6030-irq.c
@@ -36,6 +36,7 @@
 #include <linux/irq.h>
 #include <linux/kthread.h>
 #include <linux/i2c/twl.h>
+#include <linux/platform_device.h>
 
 /*
  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
@@ -223,6 +224,78 @@ int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
 }
 EXPORT_SYMBOL(twl6030_interrupt_mask);
 
+int twl6030_mmc_card_detect_config(void)
+{
+	int ret;
+	u8 reg_val = 0;
+
+	/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
+	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
+						REG_INT_MSK_LINE_B);
+	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
+						REG_INT_MSK_STS_B);
+	/*
+	 * Intially Configuring MMC_CTRL for receving interrupts &
+	 * Card status on TWL6030 for MMC1
+	 */
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
+	if (ret < 0) {
+		pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
+		return ret;
+	}
+	reg_val &= ~VMMC_AUTO_OFF;
+	reg_val |= SW_FC;
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
+	if (ret < 0) {
+		pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
+		return ret;
+	}
+
+	/* Configuring PullUp-PullDown register */
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
+						TWL6030_CFG_INPUT_PUPD3);
+	if (ret < 0) {
+		pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
+									ret);
+		return ret;
+	}
+	reg_val &= ~(MMC_PU | MMC_PD);
+	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
+						TWL6030_CFG_INPUT_PUPD3);
+	if (ret < 0) {
+		pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
+									ret);
+		return ret;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
+
+int twl6030_mmc_card_detect(struct device *dev, int slot)
+{
+	int ret = -EIO;
+	u8 read_reg = 0;
+	struct platform_device *pdev = to_platform_device(dev);
+
+	if (pdev->id) {
+		/* TWL6030 provide's Card detect support for
+		 * only MMC1 controller.
+		 */
+		pr_err("Unkown MMC controller %d in %s\n", pdev->id, __func__);
+		return ret;
+	}
+	/*
+	 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
+	 * 0 - Card not present ,1 - Card present
+	 */
+	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
+						TWL6030_MMCCTRL);
+	if (ret >= 0)
+		ret = read_reg & STS_MMC;
+	return ret;
+}
+EXPORT_SYMBOL(twl6030_mmc_card_detect);
+
 int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 {