leds-lp55xx: support firmware interface
This patch provides additional device attributes which enable
loading the firmware. ('select_engine' and 'run_engine')
To run a LED pattern, two parts of driver should be enabled.
Common features : lp55xx-common
===============================
Firmware interface for loading LED patterns
Chip specific features : leds-lp5521, leds-lp5523
=================================================
Register addresses for loading firmware data
Register addresses for running selected engine
Pattern programming sequence
============================
LP55xx chips have three program engines.
To load and run a LED pattern, the programming sequence is as follows.
(1) Select an engine number (1/2/3)
(2) Set engine mode to load
(3) Write pattern data into selected area
(4) Set engine mode to run
This sequence is almost same as the firmware interface.
(1) Select an engine number : 'select_engine' dev attribute
(2) Mode change to load : 'loading' of firmware class
(3) Write pattern data into selected area : 'data' of firmware class
(4) Mode change to run : 'run_engine' dev attribute
(1) and (4) are device specific features which provide callback functions
(2) and (3) are common features.
For example,
echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
echo 1 > /sys/class/firmware/lp5521/loading
echo "4000600040FF6000" > /sys/class/firmware/lp5521/data
echo 0 > /sys/class/firmware/lp5521/loading
echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
As soon as 'loading' is set to 0, registered callback is called.
Inside the callback, the selected engine is loaded and memory is updated.
To run programmed pattern, 'run_engine' attribute should be enabled.
Device specific data structure
==============================
o Firmware callback
load selected engine and update program memory
o Run engine
change the engine mode
o 'engine_idx' and firmware data, 'fw'
Those are used in the driver internally with callback functions
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
diff --git a/drivers/leds/leds-lp55xx-common.h b/drivers/leds/leds-lp55xx-common.h
index d0be837..8473abf 100644
--- a/drivers/leds/leds-lp55xx-common.h
+++ b/drivers/leds/leds-lp55xx-common.h
@@ -15,6 +15,13 @@
#ifndef _LEDS_LP55XX_COMMON_H
#define _LEDS_LP55XX_COMMON_H
+enum lp55xx_engine_index {
+ LP55XX_ENGINE_INVALID,
+ LP55XX_ENGINE_1,
+ LP55XX_ENGINE_2,
+ LP55XX_ENGINE_3,
+};
+
struct lp55xx_led;
struct lp55xx_chip;
@@ -36,6 +43,8 @@
* @post_init_device : Chip specific initialization code
* @brightness_work_fn : Brightness work function
* @set_led_current : LED current set function
+ * @firmware_cb : Call function when the firmware is loaded
+ * @run_engine : Run internal engine for pattern
*/
struct lp55xx_device_config {
const struct lp55xx_reg reset;
@@ -50,6 +59,12 @@
/* current setting function */
void (*set_led_current) (struct lp55xx_led *led, u8 led_current);
+
+ /* access program memory when the firmware is loaded */
+ void (*firmware_cb)(struct lp55xx_chip *chip);
+
+ /* used for running firmware LED patterns */
+ void (*run_engine) (struct lp55xx_chip *chip, bool start);
};
/*
@@ -59,6 +74,8 @@
* @lock : Lock for user-space interface
* @num_leds : Number of registered LEDs
* @cfg : Device specific configuration data
+ * @engine_idx : Selected engine number
+ * @fw : Firmware data for running a LED pattern
*/
struct lp55xx_chip {
struct i2c_client *cl;
@@ -66,6 +83,8 @@
struct mutex lock; /* lock for user-space interface */
int num_leds;
struct lp55xx_device_config *cfg;
+ enum lp55xx_engine_index engine_idx;
+ const struct firmware *fw;
};
/*