The implementation makes use of the new fan control virtual registers
exposed by the pmbus core. It mixes use of the default implementations
with some overrides via the read/write handlers to handle FAN_COMMAND_1
on the MAX31785, whose definition breaks the value range into various
control bands dependent on RPM or PWM mode.
Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx>
---
Documentation/hwmon/max31785 | 4 ++
drivers/hwmon/pmbus/max31785.c | 104 ++++++++++++++++++++++++++++++++++++++++-
2 files changed, 107 insertions(+), 1 deletion(-)
diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785
index 45fb6093dec2..e9edbf11948f 100644
--- a/Documentation/hwmon/max31785
+++ b/Documentation/hwmon/max31785
@@ -32,6 +32,7 @@ Sysfs attributes
fan[1-4]_alarm Fan alarm.
fan[1-4]_fault Fan fault.
fan[1-4]_input Fan RPM.
+fan[1-4]_target Fan input target
in[1-6]_crit Critical maximum output voltage
in[1-6]_crit_alarm Output voltage critical high alarm
@@ -44,6 +45,9 @@ in[1-6]_max_alarm Output voltage high alarm
in[1-6]_min Minimum output voltage
in[1-6]_min_alarm Output voltage low alarm
+pwm[1-4] Fan target duty cycle (0..255)
+pwm[1-4]_enable 0: full-speed, 1: manual control, 2: automatic
+
temp[1-11]_crit Critical high temperature
temp[1-11]_crit_alarm Chip temperature critical high alarm
temp[1-11]_input Measured temperature
diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c
index 9313849d5160..0d97ddf67079 100644
--- a/drivers/hwmon/pmbus/max31785.c
+++ b/drivers/hwmon/pmbus/max31785.c
@@ -20,8 +20,102 @@ enum max31785_regs {
#define MAX31785_NR_PAGES 23
+static int max31785_get_pwm(struct i2c_client *client, int page)
+{
+ int config;
+ int command;
+
+ config = pmbus_read_byte_data(client, page, PMBUS_FAN_CONFIG_12);
+ if (config < 0)
+ return config;
+
+ command = pmbus_read_word_data(client, page, PMBUS_FAN_COMMAND_1);
+ if (command < 0)
+ return command;
+
+ if (!(config & PB_FAN_1_RPM)) {
+ if (command >= 0x8000)
+ return 0;
+ else if (command >= 0x2711)
+ return 0x2710;
+
+ return command;
+ }
+
+ return 0;
+}
+
+static int max31785_get_pwm_mode(struct i2c_client *client, int page)
+{
+ int config;
+ int command;
+
+ config = pmbus_read_byte_data(client, page, PMBUS_FAN_CONFIG_12);
+ if (config < 0)
+ return config;
+
+ command = pmbus_read_word_data(client, page, PMBUS_FAN_COMMAND_1);
+ if (command < 0)
+ return command;
+
+ if (!(config & PB_FAN_1_RPM)) {
+ if (command >= 0x8000)
+ return 2;
+ else if (command >= 0x2711)
+ return 0;
+
+ return 1;
+ }
+
+ return (command >= 0x8000) ? 2 : 1;
+}
+
+static int max31785_read_word_data(struct i2c_client *client, int page,
+ int reg)
+{
+ int rv;
+
+ switch (reg) {
+ case PMBUS_VIRT_PWM_1:
+ rv = max31785_get_pwm(client, page);
+ if (rv < 0)
+ return rv;
+
+ rv *= 255;
+ rv /= 100;
+ break;
+ case PMBUS_VIRT_PWM_ENABLE_1:
+ rv = max31785_get_pwm_mode(client, page);
+ break;
