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-rw-r--r--Documentation/hwmon/max66501
-rw-r--r--drivers/hwmon/max6650.c108
2 files changed, 68 insertions, 41 deletions
diff --git a/Documentation/hwmon/max6650 b/Documentation/hwmon/max6650
index 58d9644a2bde..dff1d296a48b 100644
--- a/Documentation/hwmon/max6650
+++ b/Documentation/hwmon/max6650
@@ -34,6 +34,7 @@ fan3_input ro "
fan4_input ro "
fan1_target rw desired fan speed in RPM (closed loop mode only)
pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop
+ 3=off
pwm1 rw relative speed (0-255), 255=max. speed.
Used in open loop mode only.
fan1_div rw sets the speed range the inputs can handle. Legal
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
index c87517aee83a..a993b44ed538 100644
--- a/drivers/hwmon/max6650.c
+++ b/drivers/hwmon/max6650.c
@@ -185,6 +185,30 @@ static struct max6650_data *max6650_update_device(struct device *dev)
return data;
}
+/*
+ * Change the operating mode of the chip (if needed).
+ * mode is one of the MAX6650_CFG_MODE_* values.
+ */
+static int max6650_set_operating_mode(struct max6650_data *data, u8 mode)
+{
+ int result;
+ u8 config = data->config;
+
+ if (mode == (config & MAX6650_CFG_MODE_MASK))
+ return 0;
+
+ config = (config & ~MAX6650_CFG_MODE_MASK) | mode;
+
+ result = i2c_smbus_write_byte_data(data->client, MAX6650_REG_CONFIG,
+ config);
+ if (result < 0)
+ return result;
+
+ data->config = config;
+
+ return 0;
+}
+
static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
char *buf)
{
@@ -266,18 +290,12 @@ static ssize_t get_target(struct device *dev, struct device_attribute *devattr,
return sprintf(buf, "%d\n", rpm);
}
-static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
- const char *buf, size_t count)
+static int max6650_set_target(struct max6650_data *data, unsigned long rpm)
{
- struct max6650_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
int kscale, ktach;
- unsigned long rpm;
- int err;
- err = kstrtoul(buf, 10, &rpm);
- if (err)
- return err;
+ if (rpm == 0)
+ return max6650_set_operating_mode(data, MAX6650_CFG_MODE_OFF);
rpm = clamp_val(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
@@ -288,8 +306,6 @@ static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
* KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
*/
- mutex_lock(&data->update_lock);
-
kscale = DIV_FROM_REG(data->config);
ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
if (ktach < 0)
@@ -298,10 +314,30 @@ static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
ktach = 255;
data->speed = ktach;
- i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed);
+ return i2c_smbus_write_byte_data(data->client, MAX6650_REG_SPEED,
+ data->speed);
+}
+
+static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ struct max6650_data *data = dev_get_drvdata(dev);
+ unsigned long rpm;
+ int err;
+
+ err = kstrtoul(buf, 10, &rpm);
+ if (err)
+ return err;
+
+ mutex_lock(&data->update_lock);
+
+ err = max6650_set_target(data, rpm);
mutex_unlock(&data->update_lock);
+ if (err < 0)
+ return err;
+
return count;
}
@@ -355,12 +391,11 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
data->dac = 180 - (180 * pwm)/255;
else
data->dac = 76 - (76 * pwm)/255;
-
- i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
+ err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
mutex_unlock(&data->update_lock);
- return count;
+ return err < 0 ? err : count;
}
/*
@@ -369,14 +404,14 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
* 0 = Fan always on
* 1 = Open loop, Voltage is set according to speed, not regulated.
* 2 = Closed loop, RPM for all fans regulated by fan1 tachometer
+ * 3 = Fan off
*/
-
static ssize_t get_enable(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct max6650_data *data = max6650_update_device(dev);
int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
- int sysfs_modes[4] = {0, 1, 2, 1};
+ int sysfs_modes[4] = {0, 3, 2, 1};
return sprintf(buf, "%d\n", sysfs_modes[mode]);
}
@@ -385,25 +420,25 @@ static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
struct max6650_data *data = dev_get_drvdata(dev);
- struct i2c_client *client = data->client;
- int max6650_modes[3] = {0, 3, 2};
unsigned long mode;
int err;
+ const u8 max6650_modes[] = {
+ MAX6650_CFG_MODE_ON,
+ MAX6650_CFG_MODE_OPEN_LOOP,
+ MAX6650_CFG_MODE_CLOSED_LOOP,
+ MAX6650_CFG_MODE_OFF,
+ };
err = kstrtoul(buf, 10, &mode);
if (err)
return err;
- if (mode > 2)
+ if (mode >= ARRAY_SIZE(max6650_modes))
return -EINVAL;
mutex_lock(&data->update_lock);
- data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
- data->config = (data->config & ~MAX6650_CFG_MODE_MASK)
- | (max6650_modes[mode] << 4);
-
- i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config);
+ max6650_set_operating_mode(data, max6650_modes[mode]);
mutex_unlock(&data->update_lock);
@@ -582,6 +617,7 @@ static int max6650_init_client(struct max6650_data *data,
int err = -EIO;
u32 voltage;
u32 prescale;
+ u32 target_rpm;
if (of_property_read_u32(dev->of_node, "maxim,fan-microvolt",
&voltage))
@@ -642,22 +678,6 @@ static int max6650_init_client(struct max6650_data *data,
(config & MAX6650_CFG_V12) ? 12 : 5,
1 << (config & MAX6650_CFG_PRESCALER_MASK));
- /*
- * If mode is set to "full off", we change it to "open loop" and
- * set DAC to 255, which has the same effect. We do this because
- * there's no "full off" mode defined in hwmon specifications.
- */
-
- if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) {
- dev_dbg(dev, "Change mode to open loop, full off.\n");
- config = (config & ~MAX6650_CFG_MODE_MASK)
- | MAX6650_CFG_MODE_OPEN_LOOP;
- if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) {
- dev_err(dev, "DAC write error, aborting.\n");
- return err;
- }
- }
-
if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) {
dev_err(dev, "Config write error, aborting.\n");
return err;
@@ -666,6 +686,12 @@ static int max6650_init_client(struct max6650_data *data,
data->config = config;
data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
+ if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm",
+ &target_rpm)) {
+ max6650_set_target(data, target_rpm);
+ max6650_set_operating_mode(data, MAX6650_CFG_MODE_CLOSED_LOOP);
+ }
+
return 0;
}