pinctrl: rockchip: Special treatment for RK3288 gpio0 pins' drive strength

RK3288 pmu_gpio0 drive strength setting have no higher 16 writing
corresponding bits, need to read before write the register.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>

diff --git a/drivers/pinctrl/rockchip/pinctrl-rk3288.c b/drivers/pinctrl/rockchip/pinctrl-rk3288.c
index 6ae9f1c..d1b9aeb 100644 (file)
--- a/drivers/pinctrl/rockchip/pinctrl-rk3288.c
+++ b/drivers/pinctrl/rockchip/pinctrl-rk3288.c
@@ -143,8 +143,15 @@ static int rk3288_set_drive(struct rockchip_pin_bank *bank,
                return ret;
        }
 
-       /* enable the write to the equivalent lower bits */
-       data = ((1 << ROCKCHIP_DRV_BITS_PER_PIN) - 1) << (bit + 16);
+       /* bank0 is special, there are no higher 16 bit writing bits. */
+       if (bank->bank_num == 0) {
+               regmap_read(regmap, reg, &data);
+               data &= ~(((1 << ROCKCHIP_DRV_BITS_PER_PIN) - 1) << bit);
+       } else {
+               /* enable the write to the equivalent lower bits */
+               data = ((1 << ROCKCHIP_DRV_BITS_PER_PIN) - 1) << (bit + 16);
+       }
+
        data |= (ret << bit);
        ret = regmap_write(regmap, reg, data);
        return ret;