hwmon: (max6639) Set reasonable default PWM frequency
This patch initializes register CONFIG3 to a reasonable default PWM frequency
of 25kHz, to prevent audible sound in fan.
Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index 40fd878..f20d997 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -64,9 +64,12 @@
#define MAX6639_GCONFIG_POR 0x40
#define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
#define MAX6639_GCONFIG_CH2_LOCAL 0x10
+#define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
#define MAX6639_FAN_CONFIG1_PWM 0x80
+#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
+
static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
#define FAN_FROM_REG(val, div, rpm_range) ((val) == 0 ? -1 : \
@@ -430,7 +433,7 @@
int rpm_range = 1; /* default: 4000 RPM */
int err = 0;
- /* Reset chip to default values */
+ /* Reset chip to default values, see below for GCONFIG setup */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_POR);
if (err)
@@ -472,6 +475,16 @@
if (err)
goto exit;
+ /*
+ * /THERM full speed enable,
+ * PWM frequency 25kHz, see also GCONFIG below
+ */
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_CONFIG3(i),
+ MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
+ if (err)
+ goto exit;
+
/* Max. temp. 80C/90C/100C */
data->temp_therm[i] = 80;
data->temp_alert[i] = 90;
@@ -500,7 +513,8 @@
}
/* Start monitoring */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
- MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL);
+ MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
+ MAX6639_GCONFIG_PWM_FREQ_HI);
exit:
return err;
}