hwmon: (core) Add basic pwm attribute support to new API

Add basic pwm attribute support (no auto attributes) to new API.

Reviewed-by: Jonathan Cameron <[e-mail]>
Signed-off-by: Guenter Roeck <[e-mail]>

Documentation/hwmon/hwmon-kernel-api.txt

···
   * hwmon_energy	Energy sensor
   * hwmon_humidity	Humidity sensor
   * hwmon_fan		Fan speed sensor
+  * hwmon_pwm		PWM control
 
 * config: Pointer to a 0-terminated list of configuration values for each
   sensor of the given type. Each value is a combination of bit values
···
 HWMON_E_xxxx	Energy attributes, for use with hwmon_energy.
 HWMON_H_xxxx	Humidity attributes, for use with hwmon_humidity.
 HWMON_F_xxxx	Fan speed attributes, for use with hwmon_fan.
+HWMON_PWM_xxxx	PWM control attributes, for use with hwmon_pwm.
 
 Driver callback functions
 -------------------------

drivers/hwmon/hwmon.c

···
 	[hwmon_fan_fault] = "fan%d_fault",
 };
 
+static const char * const hwmon_pwm_attr_templates[] = {
+	[hwmon_pwm_input] = "pwm%d",
+	[hwmon_pwm_enable] = "pwm%d_enable",
+	[hwmon_pwm_mode] = "pwm%d_mode",
+	[hwmon_pwm_freq] = "pwm%d_freq",
+};
+
 static const char * const *__templates[] = {
 	[hwmon_chip] = hwmon_chip_attr_templates,
 	[hwmon_temp] = hwmon_temp_attr_templates,
···
 	[hwmon_energy] = hwmon_energy_attr_templates,
 	[hwmon_humidity] = hwmon_humidity_attr_templates,
 	[hwmon_fan] = hwmon_fan_attr_templates,
+	[hwmon_pwm] = hwmon_pwm_attr_templates,
 };
 
 static const int __templates_size[] = {
···
 	[hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
 	[hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
 	[hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
+	[hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
 };
 
 static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)

include/linux/hwmon.h

···
 	hwmon_energy,
 	hwmon_humidity,
 	hwmon_fan,
+	hwmon_pwm,
 };
 
 enum hwmon_chip_attributes {
···
 #define HWMON_F_MIN_ALARM		BIT(hwmon_fan_min_alarm)
 #define HWMON_F_MAX_ALARM		BIT(hwmon_fan_max_alarm)
 #define HWMON_F_FAULT			BIT(hwmon_fan_fault)
+
+enum hwmon_pwm_attributes {
+	hwmon_pwm_input,
+	hwmon_pwm_enable,
+	hwmon_pwm_mode,
+	hwmon_pwm_freq,
+};
+
+#define HWMON_PWM_INPUT			BIT(hwmon_pwm_input)
+#define HWMON_PWM_ENABLE		BIT(hwmon_pwm_enable)
+#define HWMON_PWM_MODE			BIT(hwmon_pwm_mode)
+#define HWMON_PWM_FREQ			BIT(hwmon_pwm_freq)
 
 /**
  * struct hwmon_ops - hwmon device operations