reset: sunxi: fix for 64-bit compilation

The Allwinner reset controller has 32-bit registers, so translating
the reset cell number into a register and bit offset should not use
any architecture dependent data size. Otherwise this breaks for 64-bit
architectures like arm64.
Fix this by making it clear that it's the hardware register width which
matters here in the calculation.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/reset/reset-sunxi.c

@@ -34,15 +34,16 @@ static int sunxi_reset_assert(struct reset_controller_dev *rcdev,
 	struct sunxi_reset_data *data = container_of(rcdev,
 						     struct sunxi_reset_data,
 						     rcdev);
-	int bank = id / BITS_PER_LONG;
-	int offset = id % BITS_PER_LONG;
+	int reg_width = sizeof(u32);
+	int bank = id / (reg_width * BITS_PER_BYTE);
+	int offset = id % (reg_width * BITS_PER_BYTE);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&data->lock, flags);
 
-	reg = readl(data->membase + (bank * 4));
-	writel(reg & ~BIT(offset), data->membase + (bank * 4));
+	reg = readl(data->membase + (bank * reg_width));
+	writel(reg & ~BIT(offset), data->membase + (bank * reg_width));
 
 	spin_unlock_irqrestore(&data->lock, flags);
 
@@ -55,15 +56,16 @@ static int sunxi_reset_deassert(struct reset_controller_dev *rcdev,
 	struct sunxi_reset_data *data = container_of(rcdev,
 						     struct sunxi_reset_data,
 						     rcdev);
-	int bank = id / BITS_PER_LONG;
-	int offset = id % BITS_PER_LONG;
+	int reg_width = sizeof(u32);
+	int bank = id / (reg_width * BITS_PER_BYTE);
+	int offset = id % (reg_width * BITS_PER_BYTE);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&data->lock, flags);
 
-	reg = readl(data->membase + (bank * 4));
-	writel(reg | BIT(offset), data->membase + (bank * 4));
+	reg = readl(data->membase + (bank * reg_width));
+	writel(reg | BIT(offset), data->membase + (bank * reg_width));
 
 	spin_unlock_irqrestore(&data->lock, flags);