gpu: host1x: mipi: Registers are 32 bits wide

On 64-bit platforms an unsigned long would be 64 bit and cause
unnecessary casting when being passed to writel() or returned from
readl(). Make register values 32 bits wide to avoid that.

Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/gpu/host1x/mipi.c b/drivers/gpu/host1x/mipi.c
index 9882ea1..a3e215a 100644
--- a/drivers/gpu/host1x/mipi.c
+++ b/drivers/gpu/host1x/mipi.c
@@ -90,16 +90,16 @@
 	unsigned long pads;
 };
 
-static inline unsigned long tegra_mipi_readl(struct tegra_mipi *mipi,
-					     unsigned long reg)
+static inline u32 tegra_mipi_readl(struct tegra_mipi *mipi,
+				   unsigned long offset)
 {
-	return readl(mipi->regs + (reg << 2));
+	return readl(mipi->regs + (offset << 2));
 }
 
-static inline void tegra_mipi_writel(struct tegra_mipi *mipi,
-				     unsigned long value, unsigned long reg)
+static inline void tegra_mipi_writel(struct tegra_mipi *mipi, u32 value,
+				     unsigned long offset)
 {
-	writel(value, mipi->regs + (reg << 2));
+	writel(value, mipi->regs + (offset << 2));
 }
 
 struct tegra_mipi_device *tegra_mipi_request(struct device *device)
@@ -161,7 +161,7 @@
 static int tegra_mipi_wait(struct tegra_mipi *mipi)
 {
 	unsigned long timeout = jiffies + msecs_to_jiffies(250);
-	unsigned long value;
+	u32 value;
 
 	while (time_before(jiffies, timeout)) {
 		value = tegra_mipi_readl(mipi, MIPI_CAL_STATUS);
@@ -177,8 +177,8 @@
 
 int tegra_mipi_calibrate(struct tegra_mipi_device *device)
 {
-	unsigned long value;
 	unsigned int i;
+	u32 value;
 	int err;
 
 	err = clk_enable(device->mipi->clk);