regulator: pbias: Handle extended drain IO when changing omap36 PBIAS

The OMAP36 and DM37 TRM state to disable extneded drain IO before
changing the PBIAS.  This patch does this before pmic writes if
the CONFIG_MMC_OMAP36XX_PINS flag is set and the cpu family is
omap36xx

Signed-off-by: Adam Ford <aford173@gmail.com>

diff --git a/drivers/power/regulator/pbias_regulator.c b/drivers/power/regulator/pbias_regulator.c
index 366f97b38b72266dc297b1437615ef1202263f16..4ed3c94e03115e06286a1bb7f41186bdebfba605 100644 (file)
--- a/drivers/power/regulator/pbias_regulator.c
+++ b/drivers/power/regulator/pbias_regulator.c
@@ -14,6 +14,11 @@
 #include <linux/bitops.h>
 #include <linux/ioport.h>
 #include <dm/read.h>
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+#include <asm/arch/sys_proto.h>
+#include <asm/io.h>
+#include <asm/arch/mux.h>
+#endif
 
 struct pbias_reg_info {
        u32 enable;
@@ -223,8 +228,11 @@ static int pbias_regulator_get_value(struct udevice *dev)
 static int pbias_regulator_set_value(struct udevice *dev, int uV)
 {
        const struct pbias_reg_info *p = dev_get_priv(dev);
-       int rc;
+       int rc, ret;
        u32 reg;
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       u32 wkup_ctrl = readl(OMAP34XX_CTRL_WKUP_CTRL);
+#endif
 
        rc = pmic_read(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
        if (rc)
@@ -240,7 +248,23 @@ static int pbias_regulator_set_value(struct udevice *dev, int uV)
        debug("Setting %s voltage to %s\n", p->name,
              (reg & p->vmode) ? "3.0v" : "1.8v");
 
-       return pmic_write(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       if (get_cpu_family() == CPU_OMAP36XX) {
+               /* Disable extended drain IO before changing PBIAS */
+               wkup_ctrl &= ~OMAP34XX_CTRL_WKUP_CTRL_GPIO_IO_PWRDNZ;
+               writel(wkup_ctrl, OMAP34XX_CTRL_WKUP_CTRL);
+       }
+#endif
+       ret = pmic_write(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       if (get_cpu_family() == CPU_OMAP36XX) {
+               /* Enable extended drain IO after changing PBIAS */
+               writel(wkup_ctrl |
+                               OMAP34XX_CTRL_WKUP_CTRL_GPIO_IO_PWRDNZ,
+                               OMAP34XX_CTRL_WKUP_CTRL);
+       }
+#endif
+       return ret;
 }
 
 static int pbias_regulator_get_enable(struct udevice *dev)
@@ -264,9 +288,20 @@ static int pbias_regulator_set_enable(struct udevice *dev, bool enable)
        const struct pbias_reg_info *p = dev_get_priv(dev);
        int rc;
        u32 reg;
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       u32 wkup_ctrl = readl(OMAP34XX_CTRL_WKUP_CTRL);
+#endif
 
        debug("Turning %s %s\n", enable ? "on" : "off", p->name);
 
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       if (get_cpu_family() == CPU_OMAP36XX) {
+               /* Disable extended drain IO before changing PBIAS */
+               wkup_ctrl &= ~OMAP34XX_CTRL_WKUP_CTRL_GPIO_IO_PWRDNZ;
+               writel(wkup_ctrl, OMAP34XX_CTRL_WKUP_CTRL);
+       }
+#endif
+
        rc = pmic_read(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
        if (rc)
                return rc;
@@ -278,6 +313,16 @@ static int pbias_regulator_set_enable(struct udevice *dev, bool enable)
                reg |= p->disable_val;
 
        rc = pmic_write(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+
+#ifdef CONFIG_MMC_OMAP36XX_PINS
+       if (get_cpu_family() == CPU_OMAP36XX) {
+               /* Enable extended drain IO after changing PBIAS */
+               writel(wkup_ctrl |
+                               OMAP34XX_CTRL_WKUP_CTRL_GPIO_IO_PWRDNZ,
+                               OMAP34XX_CTRL_WKUP_CTRL);
+       }
+#endif
+
        if (rc)
                return rc;