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authorVadim Pasternak <vadimp@nvidia.com>2022-07-11 10:45:57 +0200
committerHans de Goede <hdegoede@redhat.com>2022-07-14 22:34:42 +0200
commit7964f8fc52b1b1c646615423fb4e1b6d8d685822 (patch)
treedf1eff74a6ccc4bfe1e7bae05e13aa812d4f40c9 /drivers/platform
parentplatform/x86: mlx-platform: Add COME board revision register (diff)
downloadlinux-7964f8fc52b1b1c646615423fb4e1b6d8d685822.tar.xz
linux-7964f8fc52b1b1c646615423fb4e1b6d8d685822.zip
platform/mellanox: mlxreg-io: Add locking for io operations
Add lock to protect user read/write access to the registers. Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20220711084559.62447-8-vadimp@nvidia.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Diffstat (limited to 'drivers/platform')
-rw-r--r--drivers/platform/mellanox/mlxreg-io.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/platform/mellanox/mlxreg-io.c b/drivers/platform/mellanox/mlxreg-io.c
index 2c2686d5c2fc..ddc08abf398c 100644
--- a/drivers/platform/mellanox/mlxreg-io.c
+++ b/drivers/platform/mellanox/mlxreg-io.c
@@ -31,6 +31,7 @@
* @group: sysfs attribute group;
* @groups: list of sysfs attribute group for hwmon registration;
* @regsize: size of a register value;
+ * @io_lock: user access locking;
*/
struct mlxreg_io_priv_data {
struct platform_device *pdev;
@@ -41,6 +42,7 @@ struct mlxreg_io_priv_data {
struct attribute_group group;
const struct attribute_group *groups[2];
int regsize;
+ struct mutex io_lock; /* Protects user access. */
};
static int
@@ -116,14 +118,19 @@ mlxreg_io_attr_show(struct device *dev, struct device_attribute *attr,
u32 regval = 0;
int ret;
+ mutex_lock(&priv->io_lock);
+
ret = mlxreg_io_get_reg(priv->pdata->regmap, data, 0, true,
priv->regsize, &regval);
if (ret)
goto access_error;
+ mutex_unlock(&priv->io_lock);
+
return sprintf(buf, "%u\n", regval);
access_error:
+ mutex_unlock(&priv->io_lock);
return ret;
}
@@ -145,6 +152,8 @@ mlxreg_io_attr_store(struct device *dev, struct device_attribute *attr,
if (ret)
return ret;
+ mutex_lock(&priv->io_lock);
+
ret = mlxreg_io_get_reg(priv->pdata->regmap, data, input_val, false,
priv->regsize, &regval);
if (ret)
@@ -154,9 +163,12 @@ mlxreg_io_attr_store(struct device *dev, struct device_attribute *attr,
if (ret)
goto access_error;
+ mutex_unlock(&priv->io_lock);
+
return len;
access_error:
+ mutex_unlock(&priv->io_lock);
dev_err(&priv->pdev->dev, "Bus access error\n");
return ret;
}
@@ -246,16 +258,27 @@ static int mlxreg_io_probe(struct platform_device *pdev)
return PTR_ERR(priv->hwmon);
}
+ mutex_init(&priv->io_lock);
dev_set_drvdata(&pdev->dev, priv);
return 0;
}
+static int mlxreg_io_remove(struct platform_device *pdev)
+{
+ struct mlxreg_io_priv_data *priv = dev_get_drvdata(&pdev->dev);
+
+ mutex_destroy(&priv->io_lock);
+
+ return 0;
+}
+
static struct platform_driver mlxreg_io_driver = {
.driver = {
.name = "mlxreg-io",
},
.probe = mlxreg_io_probe,
+ .remove = mlxreg_io_remove,
};
module_platform_driver(mlxreg_io_driver);