rockchip: Convert the PMU IOMUX registers into an array

This is easier to deal with when using generic code since it allows us to
use a register index instead of naming each register.

Adjust it, adding an enum to improve readability.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/arm/include/asm/arch-rockchip/pmu_rk3288.h

@@ -46,14 +46,18 @@ struct rk3288_pmu {
 	u32 gpio_op;
 
 	u32 gpio0_sel18;	/* 0x80 */
-	u32 gpio0a_iomux;
-	u32 gpio0b_iomux;
-	u32 gpio0c_iomux;
-	u32 gpio0d_iomux;
+	u32 gpio0_iomux[4];	/* a, b, c, d */
 	u32 sys_reg[4];
 };
 check_member(rk3288_pmu, sys_reg[3], 0x00a0);
 
+enum {
+	PMU_GPIO0_A	= 0,
+	PMU_GPIO0_B,
+	PMU_GPIO0_C,
+	PMU_GPIO0_D,
+};
+
 /* PMU_GPIO0_B_IOMUX */
 enum {
 	GPIO0_B7_SHIFT		= 14,

drivers/pinctrl/rockchip/pinctrl_rk3288.c

@@ -56,10 +56,10 @@ static void pinctrl_rk3288_i2c_config(struct rk3288_grf *grf,
 {
 	switch (i2c_id) {
 	case PERIPH_ID_I2C0:
-		clrsetbits_le32(&pmu->gpio0b_iomux,
+		clrsetbits_le32(&pmu->gpio0_iomux[PMU_GPIO0_B],
 				GPIO0_B7_MASK << GPIO0_B7_SHIFT,
 				GPIO0_B7_I2C0PMU_SDA << GPIO0_B7_SHIFT);
-		clrsetbits_le32(&pmu->gpio0b_iomux,
+		clrsetbits_le32(&pmu->gpio0_iomux[PMU_GPIO0_C],
 				GPIO0_C0_MASK << GPIO0_C0_SHIFT,
 				GPIO0_C0_I2C0PMU_SCL << GPIO0_C0_SHIFT);
 		break;