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Subject[PATCH 07/20] phy: exynos-mipi-video: Use spin_lock to protct state->regmap rmw operations
Date
From: Axel Lin <axel.lin@ingics.com>

The state->regmap is initialized by devm_regmap_init_mmio().
So it's fine to use spin_lock rather than mutex to protct state->regmap rmw
operations.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
[Julia.Lawall@lip6.fr: Found an issue with the original patch w.r.t unbalanced
spin_lock call]
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
---
drivers/phy/phy-exynos-mipi-video.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/phy/phy-exynos-mipi-video.c b/drivers/phy/phy-exynos-mipi-video.c
index d196493..df7519a 100644
--- a/drivers/phy/phy-exynos-mipi-video.c
+++ b/drivers/phy/phy-exynos-mipi-video.c
@@ -43,7 +43,6 @@ struct exynos_mipi_video_phy {
} phys[EXYNOS_MIPI_PHYS_NUM];
spinlock_t slock;
void __iomem *regs;
- struct mutex mutex;
struct regmap *regmap;
};

@@ -59,8 +58,9 @@ static int __set_phy_state(struct exynos_mipi_video_phy *state,
else
reset = EXYNOS4_MIPI_PHY_SRESETN;

+ spin_lock(&state->slock);
+
if (!IS_ERR(state->regmap)) {
- mutex_lock(&state->mutex);
regmap_read(state->regmap, offset, &val);
if (on)
val |= reset;
@@ -72,11 +72,9 @@ static int __set_phy_state(struct exynos_mipi_video_phy *state,
else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
val &= ~EXYNOS4_MIPI_PHY_ENABLE;
regmap_write(state->regmap, offset, val);
- mutex_unlock(&state->mutex);
} else {
addr = state->regs + EXYNOS_MIPI_PHY_CONTROL(id / 2);

- spin_lock(&state->slock);
val = readl(addr);
if (on)
val |= reset;
@@ -90,9 +88,9 @@ static int __set_phy_state(struct exynos_mipi_video_phy *state,
val &= ~EXYNOS4_MIPI_PHY_ENABLE;

writel(val, addr);
- spin_unlock(&state->slock);
}

+ spin_unlock(&state->slock);
return 0;
}

@@ -158,7 +156,6 @@ static int exynos_mipi_video_phy_probe(struct platform_device *pdev)

dev_set_drvdata(dev, state);
spin_lock_init(&state->slock);
- mutex_init(&state->mutex);

for (i = 0; i < EXYNOS_MIPI_PHYS_NUM; i++) {
struct phy *phy = devm_phy_create(dev, NULL,
--
1.7.9.5


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