[PATCH v3 2/4] mfd: cros_ec: add EC_PWM function definitions

From: Brian Norris
Date: Fri Jun 17 2016 - 15:59:42 EST


The EC_CMD_PWM_{GET,SET}_DUTY commands allow us to control a PWM that is
attached to the EC, rather than the main host SoC. The API provides
functionality-based (e.g., keyboard light, backlight) or index-based
addressing of the PWM(s). Duty cycles are represented by a 16-bit value,
where 0 maps to 0% duty cycle and U16_MAX maps to 100%. The period
cannot be controlled.

This command set is more generic than, e.g.,
EC_CMD_PWM_{GET,SET}_KEYBOARD_BACKLIGHT and could possibly used to
replace it on future products.

Let's update the command header to include the definitions.

Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
---
v3:
* convert from 65535 to 0xffff

v2:
* no changes
---
include/linux/mfd/cros_ec_commands.h | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index 13b630c10d4c..7e7a8d4b4551 100644
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -949,6 +949,37 @@ struct ec_params_pwm_set_fan_duty {
uint32_t percent;
} __packed;

+#define EC_CMD_PWM_SET_DUTY 0x25
+/* 16 bit duty cycle, 0xffff = 100% */
+#define EC_PWM_MAX_DUTY 0xffff
+
+enum ec_pwm_type {
+ /* All types, indexed by board-specific enum pwm_channel */
+ EC_PWM_TYPE_GENERIC = 0,
+ /* Keyboard backlight */
+ EC_PWM_TYPE_KB_LIGHT,
+ /* Display backlight */
+ EC_PWM_TYPE_DISPLAY_LIGHT,
+ EC_PWM_TYPE_COUNT,
+};
+
+struct ec_params_pwm_set_duty {
+ uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */
+ uint8_t pwm_type; /* ec_pwm_type */
+ uint8_t index; /* Type-specific index, or 0 if unique */
+} __packed;
+
+#define EC_CMD_PWM_GET_DUTY 0x26
+
+struct ec_params_pwm_get_duty {
+ uint8_t pwm_type; /* ec_pwm_type */
+ uint8_t index; /* Type-specific index, or 0 if unique */
+} __packed;
+
+struct ec_response_pwm_get_duty {
+ uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */
+} __packed;
+
/*****************************************************************************/
/*
* Lightbar commands. This looks worse than it is. Since we only use one HOST
--
2.8.0.rc3.226.g39d4020