Documentation: leds: update LP55xx family devices

Update changed platform data information.
 Add leds-lp55xx.txt which includes the firmware interface description.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
This commit is contained in:
Milo(Woogyom) Kim 2013-02-05 20:22:48 +09:00 committed by Bryan Wu
parent 109b833071
commit c0285f8ca8
4 changed files with 132 additions and 78 deletions

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@ -6,5 +6,7 @@ leds-lp5521.txt
- notes on how to use the leds-lp5521 driver.
leds-lp5523.txt
- notes on how to use the leds-lp5523 driver.
leds-lp55xx.txt
- description about lp55xx common driver.
leds-lm3556.txt
- notes on how to use the leds-lm3556 driver.

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@ -17,19 +17,8 @@ lp5521:channelx, where x is 0 .. 2
All three channels can be also controlled using the engine micro programs.
More details of the instructions can be found from the public data sheet.
Control interface for the engines:
x is 1 .. 3
enginex_mode : disabled, load, run
enginex_load : store program (visible only in engine load mode)
Example (start to blink the channel 2 led):
cd /sys/class/leds/lp5521:channel2/device
echo "load" > engine3_mode
echo "037f4d0003ff6000" > engine3_load
echo "run" > engine3_mode
stop the engine:
echo "disabled" > engine3_mode
LP5521 has the internal program memory for running various LED patterns.
For the details, please refer to 'firmware' section in leds-lp55xx.txt
sysfs contains a selftest entry.
The test communicates with the chip and checks that
@ -47,7 +36,7 @@ The name of each channel can be configurable.
If the name field is not defined, the default name will be set to 'xxxx:channelN'
(XXXX : pdata->label or i2c client name, N : channel number)
static struct lp5521_led_config lp5521_led_config[] = {
static struct lp55xx_led_config lp5521_led_config[] = {
{
.name = "red",
.chan_nr = 0,
@ -81,10 +70,10 @@ static void lp5521_enable(bool state)
/* Control of chip enable signal */
}
static struct lp5521_platform_data lp5521_platform_data = {
static struct lp55xx_platform_data lp5521_platform_data = {
.led_config = lp5521_led_config,
.num_channels = ARRAY_SIZE(lp5521_led_config),
.clock_mode = LP5521_CLOCK_EXT,
.clock_mode = LP55XX_CLOCK_EXT,
.setup_resources = lp5521_setup,
.release_resources = lp5521_release,
.enable = lp5521_enable,
@ -105,47 +94,9 @@ example of update_config :
LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT | \
LP5521_CLK_INT)
static struct lp5521_platform_data lp5521_pdata = {
static struct lp55xx_platform_data lp5521_pdata = {
.led_config = lp5521_led_config,
.num_channels = ARRAY_SIZE(lp5521_led_config),
.clock_mode = LP5521_CLOCK_INT,
.clock_mode = LP55XX_CLOCK_INT,
.update_config = LP5521_CONFIGS,
};
LED patterns : LP5521 has autonomous operation without external control.
Pattern data can be defined in the platform data.
example of led pattern data :
/* RGB(50,5,0) 500ms on, 500ms off, infinite loop */
static u8 pattern_red[] = {
0x40, 0x32, 0x60, 0x00, 0x40, 0x00, 0x60, 0x00,
};
static u8 pattern_green[] = {
0x40, 0x05, 0x60, 0x00, 0x40, 0x00, 0x60, 0x00,
};
static struct lp5521_led_pattern board_led_patterns[] = {
{
.r = pattern_red,
.g = pattern_green,
.size_r = ARRAY_SIZE(pattern_red),
.size_g = ARRAY_SIZE(pattern_green),
},
};
static struct lp5521_platform_data lp5521_platform_data = {
.led_config = lp5521_led_config,
.num_channels = ARRAY_SIZE(lp5521_led_config),
.clock_mode = LP5521_CLOCK_EXT,
.patterns = board_led_patterns,
.num_patterns = ARRAY_SIZE(board_led_patterns),
};
Then predefined led pattern(s) can be executed via the sysfs.
To start the pattern #1,
# echo 1 > /sys/bus/i2c/devices/xxxx/led_pattern
(xxxx : i2c bus & slave address)
To end the pattern,
# echo 0 > /sys/bus/i2c/devices/xxxx/led_pattern

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@ -27,25 +27,8 @@ c) Default
If both fields are NULL, 'lp5523' is used by default.
/sys/class/leds/lp5523:channelN (N: 0 ~ 8)
The chip provides 3 engines. Each engine can control channels without
interaction from the main CPU. Details of the micro engine code can be found
from the public data sheet. Leds can be muxed to different channels.
Control interface for the engines:
x is 1 .. 3
enginex_mode : disabled, load, run
enginex_load : microcode load (visible only in load mode)
enginex_leds : led mux control (visible only in load mode)
cd /sys/class/leds/lp5523:channel2/device
echo "load" > engine3_mode
echo "9d80400004ff05ff437f0000" > engine3_load
echo "111111111" > engine3_leds
echo "run" > engine3_mode
sysfs contains a selftest entry. It measures each channel
voltage level and checks if it looks reasonable. If the level is too high,
the led is missing; if the level is too low, there is a short circuit.
LP5523 has the internal program memory for running various LED patterns.
For the details, please refer to 'firmware' section in leds-lp55xx.txt
Selftest uses always the current from the platform data.
@ -58,7 +41,7 @@ Example platform data:
Note - chan_nr can have values between 0 and 8.
static struct lp5523_led_config lp5523_led_config[] = {
static struct lp55xx_led_config lp5523_led_config[] = {
{
.name = "D1",
.chan_nr = 0,
@ -88,10 +71,10 @@ static void lp5523_enable(bool state)
/* Control chip enable signal */
}
static struct lp5523_platform_data lp5523_platform_data = {
static struct lp55xx_platform_data lp5523_platform_data = {
.led_config = lp5523_led_config,
.num_channels = ARRAY_SIZE(lp5523_led_config),
.clock_mode = LP5523_CLOCK_EXT,
.clock_mode = LP55XX_CLOCK_EXT,
.setup_resources = lp5523_setup,
.release_resources = lp5523_release,
.enable = lp5523_enable,

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@ -0,0 +1,118 @@
LP5521/LP5523/LP55231 Common Driver
===================================
Authors: Milo(Woogyom) Kim <milo.kim@ti.com>
Description
-----------
LP5521, LP5523/55231 have common features as below.
Register access via the I2C
Device initialization/deinitialization
Create LED class devices for multiple output channels
Device attributes for user-space interface
Program memory for running LED patterns
The LP55xx common driver provides these features using exported functions.
lp55xx_init_device() / lp55xx_deinit_device()
lp55xx_register_leds() / lp55xx_unregister_leds()
lp55xx_regsister_sysfs() / lp55xx_unregister_sysfs()
( Driver Structure Data )
In lp55xx common driver, two different data structure is used.
o lp55xx_led
control multi output LED channels such as led current, channel index.
o lp55xx_chip
general chip control such like the I2C and platform data.
For example, LP5521 has maximum 3 LED channels.
LP5523/55231 has 9 output channels.
lp55xx_chip for LP5521 ... lp55xx_led #1
lp55xx_led #2
lp55xx_led #3
lp55xx_chip for LP5523 ... lp55xx_led #1
lp55xx_led #2
.
.
lp55xx_led #9
( Chip Dependent Code )
To support device specific configurations, special structure
'lpxx_device_config' is used.
Maximum number of channels
Reset command, chip enable command
Chip specific initialization
Brightness control register access
Setting LED output current
Program memory address access for running patterns
Additional device specific attributes
( Firmware Interface )
LP55xx family devices have the internal program memory for running
various LED patterns.
This pattern data is saved as a file in the user-land or
hex byte string is written into the memory through the I2C.
LP55xx common driver supports the firmware interface.
LP55xx chips have three program engines.
To load and run the pattern, the programming sequence is following.
(1) Select an engine number (1/2/3)
(2) Mode change to load
(3) Write pattern data into selected area
(4) Mode change to run
The LP55xx common driver provides simple interfaces as below.
select_engine : Select which engine is used for running program
run_engine : Start program which is loaded via the firmware interface
firmware : Load program data
For example, run blinking pattern in engine #1 of LP5521
echo 1 > /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
For example, run blinking pattern in engine #3 of LP55231
echo 3 > /sys/bus/i2c/devices/xxxx/select_engine
echo 1 > /sys/class/firmware/lp55231/loading
echo "9d0740ff7e0040007e00a0010000" > /sys/class/firmware/lp55231/data
echo 0 > /sys/class/firmware/lp55231/loading
echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
To start blinking patterns in engine #2 and #3 simultaneously,
for idx in 2 3
do
echo $idx > /sys/class/leds/red/device/select_engine
sleep 0.1
echo 1 > /sys/class/firmware/lp5521/loading
echo "4000600040FF6000" > /sys/class/firmware/lp5521/data
echo 0 > /sys/class/firmware/lp5521/loading
done
echo 1 > /sys/class/leds/red/device/run_engine
Here is another example for LP5523.
echo 2 > /sys/bus/i2c/devices/xxxx/select_engine
echo 1 > /sys/class/firmware/lp5523/loading
echo "9d80400004ff05ff437f0000" > /sys/class/firmware/lp5523/data
echo 0 > /sys/class/firmware/lp5523/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.
( 'run_engine' and 'firmware_cb' )
The sequence of running the program data is common.
But each device has own specific register addresses for commands.
To support this, 'run_engine' and 'firmware_cb' are configurable in each driver.
run_engine : Control the selected engine
firmware_cb : The callback function after loading the firmware is done.
Chip specific commands for loading and updating program memory.