pinctrl: rockchip: add drive-strength control for rk3288
From: Heiko Stuebner <heiko@...> Date: Sat, 19 Jul 2014 19:27:29 +0200
Commit-Message
The rk3288 is the first Rockchip soc handling the drive strength on a per-pin basis, while the older ones can set the drive-strength only for specific pin-groups. Therefore limit setting the drive-strength to this soc for now. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
drivers/pinctrl/pinctrl-rockchip.c | 112 +++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+)
Statistics
- 112 lines added
- 0 lines removed
Changes
---------------------- drivers/pinctrl/pinctrl-rockchip.c ----------------------
index 58c4647..c15f7f9 100644
@@ -573,6 +573,98 @@ static void rk3288_calc_pull_reg_and_bit(struct rockchip_pin_bank *bank,
}
}
+#define RK3288_DRV_PMU_OFFSET 0x70
+#define RK3288_DRV_GRF_OFFSET 0x1c0
+#define RK3288_DRV_BITS_PER_PIN 2
+#define RK3288_DRV_PINS_PER_REG 8
+#define RK3288_DRV_BANK_STRIDE 16
+static int rk3288_drv_list[] = { 2, 4, 8, 12 };
+
+static void rk3288_calc_drv_reg_and_bit(struct rockchip_pin_bank *bank,
+ int pin_num, struct regmap **regmap,
+ int *reg, u8 *bit)
+{
+ struct rockchip_pinctrl *info = bank->drvdata;
+
+ /* The first 24 pins of the first bank are located in PMU */
+ if (bank->bank_num == 0) {
+ *regmap = info->regmap_pmu;
+ *reg = RK3288_DRV_PMU_OFFSET;
+
+ *reg += ((pin_num / RK3288_DRV_PINS_PER_REG) * 4);
+ *bit = pin_num % RK3288_DRV_PINS_PER_REG;
+ *bit *= RK3288_DRV_BITS_PER_PIN;
+ } else {
+ *regmap = info->regmap_base;
+ *reg = RK3288_DRV_GRF_OFFSET;
+
+ /* correct the offset, as we're starting with the 2nd bank */
+ *reg -= 0x10;
+ *reg += bank->bank_num * RK3288_DRV_BANK_STRIDE;
+ *reg += ((pin_num / RK3288_DRV_PINS_PER_REG) * 4);
+
+ *bit = (pin_num % RK3288_DRV_PINS_PER_REG);
+ *bit *= RK3288_DRV_BITS_PER_PIN;
+ }
+}
+
+static int rk3288_get_drive(struct rockchip_pin_bank *bank, int pin_num)
+{
+ struct regmap *regmap;
+ int reg, ret;
+ u32 data;
+ u8 bit;
+
+ rk3288_calc_drv_reg_and_bit(bank, pin_num, ®map, ®, &bit);
+
+ ret = regmap_read(regmap, reg, &data);
+ if (ret)
+ return ret;
+
+ data >>= bit;
+ data &= (1 << RK3288_DRV_BITS_PER_PIN) - 1;
+
+ return rk3288_drv_list[data];
+}
+
+static int rk3288_set_drive(struct rockchip_pin_bank *bank, int pin_num,
+ int strength)
+{
+ struct rockchip_pinctrl *info = bank->drvdata;
+ struct regmap *regmap;
+ unsigned long flags;
+ int reg, ret, i;
+ u32 data;
+ u8 bit;
+
+ rk3288_calc_drv_reg_and_bit(bank, pin_num, ®map, ®, &bit);
+
+ ret = -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(rk3288_drv_list); i++) {
+ if (rk3288_drv_list[i] == strength) {
+ ret = i;
+ break;
+ }
+ }
+
+ if (ret < 0) {
+ dev_err(info->dev, "unsupported driver strength %d\n",
+ strength);
+ return ret;
+ }
+
+ spin_lock_irqsave(&bank->slock, flags);
+
+ /* enable the write to the equivalent lower bits */
+ data = ((1 << RK3288_DRV_BITS_PER_PIN) - 1) << (bit + 16);
+ data |= (ret << bit);
+
+ ret = regmap_write(regmap, reg, data);
+ spin_unlock_irqrestore(&bank->slock, flags);
+
+ return ret;
+}
+
static int rockchip_get_pull(struct rockchip_pin_bank *bank, int pin_num)
{
struct rockchip_pinctrl *info = bank->drvdata;
@@ -888,6 +980,15 @@ static int rockchip_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
if (rc)
return rc;
break;
+ case PIN_CONFIG_DRIVE_STRENGTH:
+ /* rk3288 is the first with per-pin drive-strength */
+ if (info->ctrl->type != RK3288)
+ return -ENOTSUPP;
+
+ rc = rk3288_set_drive(bank, pin - bank->pin_base, arg);
+ if (rc < 0)
+ return rc;
+ break;
default:
return -ENOTSUPP;
break;
@@ -937,6 +1038,17 @@ static int rockchip_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
arg = rc ? 1 : 0;
break;
+ case PIN_CONFIG_DRIVE_STRENGTH:
+ /* rk3288 is the first with per-pin drive-strength */
+ if (info->ctrl->type != RK3288)
+ return -ENOTSUPP;
+
+ rc = rk3288_get_drive(bank, pin - bank->pin_base);
+ if (rc < 0)
+ return rc;
+
+ arg = rc;
+ break;
default:
return -ENOTSUPP;
break;