]> git.openfabrics.org - ~shefty/rdma-dev.git/commitdiff
hwmon: (f75375s) Catch some attempts to write to r/o registers
authorNikolaus Schulz <mail@microschulz.de>
Tue, 28 Feb 2012 21:15:54 +0000 (16:15 -0500)
committerGuenter Roeck <guenter.roeck@ericsson.com>
Fri, 2 Mar 2012 20:02:23 +0000 (12:02 -0800)
It makes no sense to attempt to manually configure the fan in auto mode,
or set the duty cycle directly in closed loop mode.  The corresponding
registers are then read-only.  If the user tries it nonetheless, error out
with EINVAL instead of silently doing nothing.

Signed-off-by: Nikolaus Schulz <mail@microschulz.de>
[guenter.roeck@ericsson.com: Minor formatting cleanup]
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
drivers/hwmon/f75375s.c

index 9ab034a1b4c1ff059cdd5388760751d76261bd03..6aa5a9fad87930800649fd4e0d17087325539530 100644 (file)
@@ -279,6 +279,21 @@ static bool duty_mode_enabled(u8 pwm_enable)
        }
 }
 
+static bool auto_mode_enabled(u8 pwm_enable)
+{
+       switch (pwm_enable) {
+       case 0: /* Manual, duty mode (full speed) */
+       case 1: /* Manual, duty mode */
+       case 3: /* Manual, speed mode */
+               return false;
+       case 2: /* Auto, speed mode */
+       case 4: /* Auto, duty mode */
+               return true;
+       default:
+               BUG();
+       }
+}
+
 static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t count)
 {
@@ -312,6 +327,11 @@ static ssize_t set_fan_target(struct device *dev, struct device_attribute *attr,
        if (err < 0)
                return err;
 
+       if (auto_mode_enabled(data->pwm_enable[nr]))
+               return -EINVAL;
+       if (data->kind == f75387 && duty_mode_enabled(data->pwm_enable[nr]))
+               return -EINVAL;
+
        mutex_lock(&data->update_lock);
        data->fan_target[nr] = rpm_to_reg(val);
        f75375_write16(client, F75375_REG_FAN_EXP(nr), data->fan_target[nr]);
@@ -332,6 +352,10 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
        if (err < 0)
                return err;
 
+       if (auto_mode_enabled(data->pwm_enable[nr]) ||
+           !duty_mode_enabled(data->pwm_enable[nr]))
+               return -EINVAL;
+
        mutex_lock(&data->update_lock);
        data->pwm[nr] = SENSORS_LIMIT(val, 0, 255);
        f75375_write_pwm(client, nr);
@@ -793,6 +817,9 @@ static void f75375_init(struct i2c_client *client, struct f75375_data *data,
        set_pwm_enable_direct(client, 0, f75375s_pdata->pwm_enable[0]);
        set_pwm_enable_direct(client, 1, f75375s_pdata->pwm_enable[1]);
        for (nr = 0; nr < 2; nr++) {
+               if (auto_mode_enabled(f75375s_pdata->pwm_enable[nr]) ||
+                   !duty_mode_enabled(f75375s_pdata->pwm_enable[nr]))
+                       continue;
                data->pwm[nr] = SENSORS_LIMIT(f75375s_pdata->pwm[nr], 0, 255);
                f75375_write_pwm(client, nr);
        }