hwmon: (amc6821) Add support for pwm1_mode attribute

AMC6821 supports configuring if a fan is DC or PWM controlled.
Add support for the pwm1_mode attribute to make it runtime configurable.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/Documentation/hwmon/amc6821.rst b/Documentation/hwmon/amc6821.rst
index 96e604c5ea8eaf0b97385f0744e687ee80f99232..dbd544cd1160e8fa542a505f00499838d5796e97 100644 (file)
--- a/Documentation/hwmon/amc6821.rst
+++ b/Documentation/hwmon/amc6821.rst
@@ -58,6 +58,7 @@ pwm1_enable           rw      regulator mode, 1=open loop, 2=fan controlled
                                remote-sensor temperature,
                                4=fan controlled by target rpm set with
                                fan1_target attribute.
+pwm1_mode              rw      Fan duty control mode (0=DC, 1=PWM)
 pwm1_auto_channels_temp ro     1 if pwm_enable==2, 3 if pwm_enable==3
 pwm1_auto_point1_pwm   ro      Hardwired to 0, shared for both
                                temperature channels.

diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
index 8beaea9ecbabaf98eca2e1b6d73f727a27cda94d..ec94392fcb658ff98d9e7033e0e31bfca3d37cea 100644 (file)
--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -312,6 +312,12 @@ static int amc6821_pwm_read(struct device *dev, u32 attr, long *val)
                        break;
                }
                return 0;
+       case hwmon_pwm_mode:
+               err = regmap_read(regmap, AMC6821_REG_CONF2, &regval);
+               if (err)
+                       return err;
+               *val = !!(regval & AMC6821_CONF2_TACH_MODE);
+               return 0;
        case hwmon_pwm_auto_channels_temp:
                err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
                if (err)
@@ -367,6 +373,13 @@ static int amc6821_pwm_write(struct device *dev, u32 attr, long val)
                return regmap_update_bits(regmap, AMC6821_REG_CONF1,
                                          AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
                                          mode);
+       case hwmon_pwm_mode:
+               if (val < 0 || val > 1)
+                       return -EINVAL;
+               return regmap_update_bits(regmap, AMC6821_REG_CONF2,
+                                         AMC6821_CONF2_TACH_MODE,
+                                         val ? AMC6821_CONF2_TACH_MODE : 0);
+               break;
        case hwmon_pwm_input:
                if (val < 0 || val > 255)
                        return -EINVAL;
@@ -748,6 +761,7 @@ static umode_t amc6821_is_visible(const void *data,
                }
        case hwmon_pwm:
                switch (attr) {
+               case hwmon_pwm_mode:
                case hwmon_pwm_enable:
                case hwmon_pwm_input:
                        return 0644;
@@ -774,7 +788,7 @@ static const struct hwmon_channel_info * const amc6821_info[] = {
                           HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX |
                           HWMON_F_TARGET | HWMON_F_PULSES | HWMON_F_FAULT),
        HWMON_CHANNEL_INFO(pwm,
-                          HWMON_PWM_INPUT | HWMON_PWM_ENABLE |
+                          HWMON_PWM_INPUT | HWMON_PWM_ENABLE | HWMON_PWM_MODE |
                           HWMON_PWM_AUTO_CHANNELS_TEMP),
        NULL
 };