[RFC PATCH 1/4] pinctrl: rockchip: remove unnecessary locking

John Keeping
2017-03-13T18:38:10Z

regmap_update_bits does its own locking and everything else accessed
here is a local variable so there is no need to lock around it.

I originally wrote this on to of v4.4 which doesn't have the split
registers for drive strength, where some additional locking might be
necessary. But I don't think it can be "slock" given that the following
patches will convert that to a raw spinlock and regmap uses a normal
spinlock internally.

Signed-off-by: John Keeping <john@metanate.com>
---
drivers/pinctrl/pinctrl-rockchip.c | 20 +-------------------
1 file changed, 1 insertion(+), 19 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c
index a838c8bb3129..1defe83a5c4d 100644
--- a/drivers/pinctrl/pinctrl-rockchip.c
+++ b/drivers/pinctrl/pinctrl-rockchip.c
@@ -649,7 +649,6 @@ static int rockchip_set_mux(struct rockchip_pin_bank *bank, int pin, int mux)
int iomux_num = (pin / 8);
struct regmap *regmap;
int reg, ret, mask, mux_type;
- unsigned long flags;
u8 bit;
u32 data, rmask;

@@ -698,15 +697,11 @@ static int rockchip_set_mux(struct rockchip_pin_bank *bank, int pin, int mux)
if (ctrl->iomux_recalc && (mux_type & IOMUX_RECALCED))
ctrl->iomux_recalc(bank->bank_num, pin, &reg, &bit, &mask);

- spin_lock_irqsave(&bank->slock, flags);
-
data = (mask << (bit + 16));
rmask = data | (data >> 16);
data |= (mux & mask) << bit;
ret = regmap_update_bits(regmap, reg, rmask, data);

- spin_unlock_irqrestore(&bank->slock, flags);
-
return ret;
}

@@ -1132,7 +1127,6 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
struct rockchip_pinctrl *info = bank->drvdata;
struct rockchip_pin_ctrl *ctrl = info->ctrl;
struct regmap *regmap;
- unsigned long flags;
int reg, ret, i;
u32 data, rmask, rmask_bits, temp;
u8 bit;
@@ -1160,8 +1154,6 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
return ret;
}

- spin_lock_irqsave(&bank->slock, flags);
-
switch (drv_type) {
case DRV_TYPE_IO_1V8_3V0_AUTO:
case DRV_TYPE_IO_3V3_ONLY:
@@ -1182,17 +1174,14 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
rmask = BIT(15) | BIT(31);
data |= BIT(31);
ret = regmap_update_bits(regmap, reg, rmask, data);
- if (ret) {
- spin_unlock_irqrestore(&bank->slock, flags);
+ if (ret)
return ret;
- }

rmask = 0x3 | (0x3 << 16);
temp |= (0x3 << 16);
reg += 0x4;
ret = regmap_update_bits(regmap, reg, rmask, temp);

- spin_unlock_irqrestore(&bank->slock, flags);
return ret;
case 18 ... 21:
/* setting fully enclosed in the second register */
@@ -1200,7 +1189,6 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
bit -= 16;
break;
default:
- spin_unlock_irqrestore(&bank->slock, flags);
dev_err(info->dev, "unsupported bit: %d for pinctrl drive type: %d\n",
bit, drv_type);
return -EINVAL;
@@ -1212,7 +1200,6 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
rmask_bits = RK3288_DRV_BITS_PER_PIN;
break;
default:
- spin_unlock_irqrestore(&bank->slock, flags);
dev_err(info->dev, "unsupported pinctrl drive type: %d\n",
drv_type);
return -EINVAL;
@@ -1224,7 +1211,6 @@ static int rockchip_set_drive_perpin(struct rockchip_pin_bank *bank,
data |= (ret << bit);

ret = regmap_update_bits(regmap, reg, rmask, data);
- spin_unlock_irqrestore(&bank->slock, flags);

return ret;
}
@@ -1336,16 +1322,12 @@ static int rockchip_set_pull(struct rockchip_pin_bank *bank,
return ret;
}

- spin_lock_irqsave(&bank->slock, flags);
-
/* enable the write to the equivalent lower bits */
data = ((1 << RK3188_PULL_BITS_PER_PIN) - 1) << (bit + 16);
rmask = data | (data >> 16);
data |= (ret << bit);

ret = regmap_update_bits(regmap, reg, rmask, data);
-
- spin_unlock_irqrestore(&bank->slock, flags);
break;
default:
dev_err(info->dev, "unsupported pinctrl type\n");
--
2.12.0.377.gf910686b23.dirty