ARM: i.MX: iim: Add regulator support

The voltage for programming the fuses is external to the SoC and
on some boards this is controllable with a regulator, so add regulator
support to the iim driver.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 44 insertions, 16 deletions

diff --git a/arch/arm/mach-imx/iim.c b/arch/arm/mach-imx/iim.c
index 294f41c125..16ba678842 100644
--- a/arch/arm/mach-imx/iim.c
+++ b/arch/arm/mach-imx/iim.c
@@ -26,6 +26,8 @@
 #include <malloc.h>
 #include <of.h>
 #include <io.h>
+#include <regulator.h>
+#include <linux/err.h>
 
 #include <mach/iim.h>
 #include <mach/imx51-regs.h>
@@ -53,6 +55,7 @@ struct iim_priv {
 	int write_enable;
 	int sense_enable;
 	void (*supply)(int enable);
+	struct regulator *fuse_supply;
 };
 
 struct imx_iim_drvdata {
@@ -139,7 +142,7 @@ int imx_iim_read(unsigned int banknum, int offset, void *buf, int count)
 	return imx_iim_cdev_read(&bank->cdev, buf, count, offset, 0);
 }
 
-static int imx_iim_fuse_blow(struct iim_bank *bank, unsigned int row, u8 value)
+static int imx_iim_fuse_blow_one(struct iim_bank *bank, unsigned int row, u8 value)
 {
 	struct iim_priv *iim = bank->iim;
 	void __iomem *reg_base = iim->base;
@@ -195,30 +198,53 @@ out:
 	return ret;
 }
 
+static int imx_iim_fuse_blow(struct iim_bank *bank, unsigned offset, const void *buf,
+		unsigned size)
+{
+	struct iim_priv *iim = bank->iim;
+	int ret, i;
+
+	if (IS_ERR(iim->fuse_supply)) {
+		iim->fuse_supply = regulator_get(iim->dev.parent, "vdd-fuse");
+		dev_info(iim->dev.parent, "regul: %p\n", iim->fuse_supply);
+		if (IS_ERR(iim->fuse_supply))
+			return PTR_ERR(iim->fuse_supply);
+	}
+
+	ret = regulator_enable(iim->fuse_supply);
+	if (ret < 0)
+		return ret;
+
+	if (iim->supply)
+		iim->supply(1);
+
+	for (i = 0; i < size; i++) {
+		ret = imx_iim_fuse_blow_one(bank, offset + i, ((u8 *)buf)[i]);
+		if (ret < 0)
+			goto err_out;
+	}
+
+	if (iim->supply)
+		iim->supply(0);
+
+	ret = 0;
+
+err_out:
+	regulator_disable(iim->fuse_supply);
+
+	return ret;
+}
+
 static ssize_t imx_iim_cdev_write(struct cdev *cdev, const void *buf, size_t count,
 		loff_t offset, ulong flags)
 {
 	ulong size, i;
 	struct iim_bank *bank = container_of(cdev, struct iim_bank, cdev);
-	struct iim_priv *iim = bank->iim;
 
 	size = min((loff_t)count, 32 - offset);
 
 	if (IS_ENABLED(CONFIG_IMX_IIM_FUSE_BLOW) && bank->iim->write_enable) {
-		if (iim->supply)
-			iim->supply(1);
-
-		for (i = 0; i < size; i++) {
-			int ret;
-
-			ret = imx_iim_fuse_blow(bank, offset + i, ((u8 *)buf)[i]);
-			if (ret < 0)
-				return ret;
-		}
-
-		if (iim->supply)
-			iim->supply(0);
-
+		return imx_iim_fuse_blow(bank, offset, buf, size);
 	} else {
 		for (i = 0; i < size; i++)
 			((u8 *)bank->bankbase)[(offset+i)*4] = ((u8 *)buf)[i];
@@ -382,6 +408,8 @@ static int imx_iim_probe(struct device_d *dev)
 	if (ret)
 		return ret;
 
+	iim->fuse_supply = ERR_PTR(-ENODEV);
+
 	iim->base = dev_request_mem_region(dev, 0);
 	if (!iim->base)
 		return -EBUSY;