diff options
| author | Neil Armstrong <narmstrong@baylibre.com> | 2019-07-29 15:02:17 +0200 |
|---|---|---|
| committer | Kevin Hilman <khilman@baylibre.com> | 2019-08-05 22:39:55 +0200 |
| commit | 3a760d986568b67d1f8411dab64608075817b90d (patch) | |
| tree | 7fd9d7521c34e98ed9b2c4b8e5ca24debd9afd9e /drivers/soc | |
| parent | Linus 5.3-rc1 (diff) | |
| download | linux-3a760d986568b67d1f8411dab64608075817b90d.tar.xz linux-3a760d986568b67d1f8411dab64608075817b90d.zip | |
soc: amlogic: meson-clk-measure: protect measure with a mutex
In order to protect clock measuring when multiple process asks for
a measure, protect the main measure function with mutexes.
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Diffstat (limited to 'drivers/soc')
| -rw-r--r-- | drivers/soc/amlogic/meson-clk-measure.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/soc/amlogic/meson-clk-measure.c b/drivers/soc/amlogic/meson-clk-measure.c index 19d4cbc93a17..c470e24f1dfa 100644 --- a/drivers/soc/amlogic/meson-clk-measure.c +++ b/drivers/soc/amlogic/meson-clk-measure.c @@ -11,6 +11,8 @@ #include <linux/debugfs.h> #include <linux/regmap.h> +static DEFINE_MUTEX(measure_lock); + #define MSR_CLK_DUTY 0x0 #define MSR_CLK_REG0 0x4 #define MSR_CLK_REG1 0x8 @@ -360,6 +362,10 @@ static int meson_measure_id(struct meson_msr_id *clk_msr_id, unsigned int val; int ret; + ret = mutex_lock_interruptible(&measure_lock); + if (ret) + return ret; + regmap_write(priv->regmap, MSR_CLK_REG0, 0); /* Set measurement duration */ @@ -377,8 +383,10 @@ static int meson_measure_id(struct meson_msr_id *clk_msr_id, ret = regmap_read_poll_timeout(priv->regmap, MSR_CLK_REG0, val, !(val & MSR_BUSY), 10, 10000); - if (ret) + if (ret) { + mutex_unlock(&measure_lock); return ret; + } /* Disable */ regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_ENABLE, 0); @@ -386,6 +394,8 @@ static int meson_measure_id(struct meson_msr_id *clk_msr_id, /* Get the value in multiple of gate time counts */ regmap_read(priv->regmap, MSR_CLK_REG2, &val); + mutex_unlock(&measure_lock); + if (val >= MSR_VAL_MASK) return -EINVAL; |