diff options
| author | Armin Wolf <W_Armin@gmx.de> | 2023-09-07 07:26:36 +0200 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2023-10-27 07:27:24 -0700 |
| commit | 7da8a635436029957c5350da3acf51d78ed64071 (patch) | |
| tree | 9f9e04c8bce95fb0bcdecee07a5464e1326a4b50 /drivers/hwmon/sch5627.c | |
| parent | 7f0b28e0653f36b51542d25dd54ed312c397ecfc (diff) | |
| download | lwn-7da8a635436029957c5350da3acf51d78ed64071.tar.gz lwn-7da8a635436029957c5350da3acf51d78ed64071.zip | |
hwmon: (sch5627) Disallow write access if virtual registers are locked
When the lock bit inside SCH5627_REG_CTRL is set, then the virtual
registers become read-only until the next power cycle.
Disallow write access to those registers in such a case.
Tested on a Fujitsu Esprimo P720.
Fixes: aa9f833dfc12 ("hwmon: (sch5627) Add pwmX_auto_channels_temp support")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20230907052639.16491-3-W_Armin@gmx.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/sch5627.c')
| -rw-r--r-- | drivers/hwmon/sch5627.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/hwmon/sch5627.c b/drivers/hwmon/sch5627.c index 0eefb8c0aef2..bf408e35e2c3 100644 --- a/drivers/hwmon/sch5627.c +++ b/drivers/hwmon/sch5627.c @@ -34,6 +34,7 @@ #define SCH5627_REG_CTRL 0x40 #define SCH5627_CTRL_START BIT(0) +#define SCH5627_CTRL_LOCK BIT(1) #define SCH5627_CTRL_VBAT BIT(4) #define SCH5627_NO_TEMPS 8 @@ -231,6 +232,14 @@ static int reg_to_rpm(u16 reg) static umode_t sch5627_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr, int channel) { + const struct sch5627_data *data = drvdata; + + /* Once the lock bit is set, the virtual registers become read-only + * until the next power cycle. + */ + if (data->control & SCH5627_CTRL_LOCK) + return 0444; + if (type == hwmon_pwm && attr == hwmon_pwm_auto_channels_temp) return 0644; |