hwmon: (pmbus) Enable PEC if the controller supports it

PMBus controllers optionally support PEC. Configure the driver
to use it if available to improve operational security.

Suggested-by: Michael Jones <mike@proclivis.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 3981981..ba59eae 100644 (file)
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -1751,6 +1751,11 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
                }
        }
 
+       /* Enable PEC if the controller supports it */
+       ret = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY);
+       if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK))
+               client->flags |= I2C_CLIENT_PEC;
+
        pmbus_clear_faults(client);
 
        if (info->identify) {