- 根目录:
- drivers
- leds
- leds-lp5521.c
/*
* LP5521 LED chip driver.
*
* Copyright (C) 2010 Nokia Corporation
* Copyright (C) 2012 Texas Instruments
*
* Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
* Milo(Woogyom) Kim <milo.kim@ti.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/of.h>
#include "leds-lp55xx-common.h"
#define LP5521_PROGRAM_LENGTH 32
#define LP5521_MAX_LEDS 3
#define LP5521_CMD_DIRECT 0x3F
/* Registers */
#define LP5521_REG_ENABLE 0x00
#define LP5521_REG_OP_MODE 0x01
#define LP5521_REG_R_PWM 0x02
#define LP5521_REG_G_PWM 0x03
#define LP5521_REG_B_PWM 0x04
#define LP5521_REG_R_CURRENT 0x05
#define LP5521_REG_G_CURRENT 0x06
#define LP5521_REG_B_CURRENT 0x07
#define LP5521_REG_CONFIG 0x08
#define LP5521_REG_STATUS 0x0C
#define LP5521_REG_RESET 0x0D
#define LP5521_REG_R_PROG_MEM 0x10
#define LP5521_REG_G_PROG_MEM 0x30
#define LP5521_REG_B_PROG_MEM 0x50
/* Base register to set LED current */
#define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
/* Base register to set the brightness */
#define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM
/* Bits in ENABLE register */
#define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
#define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
#define LP5521_EXEC_RUN 0x2A
#define LP5521_ENABLE_DEFAULT \
(LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
#define LP5521_ENABLE_RUN_PROGRAM \
(LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
/* CONFIG register */
#define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
#define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
#define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
#define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
#define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
#define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
#define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
#define LP5521_CLK_INT 0x01 /* Internal clock */
#define LP5521_DEFAULT_CFG \
(LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
/* Status */
#define LP5521_EXT_CLK_USED 0x08
/* default R channel current register value */
#define LP5521_REG_R_CURR_DEFAULT 0xAF
/* Reset register value */
#define LP5521_RESET 0xFF
/* Program Memory Operations */
#define LP5521_MODE_R_M 0x30 /* Operation Mode Register */
#define LP5521_MODE_G_M 0x0C
#define LP5521_MODE_B_M 0x03
#define LP5521_LOAD_R 0x10
#define LP5521_LOAD_G 0x04
#define LP5521_LOAD_B 0x01
#define LP5521_R_IS_LOADING(mode) \
((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
#define LP5521_G_IS_LOADING(mode) \
((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
#define LP5521_B_IS_LOADING(mode) \
((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
#define LP5521_EXEC_R_M 0x30 /* Enable Register */
#define LP5521_EXEC_G_M 0x0C
#define LP5521_EXEC_B_M 0x03
#define LP5521_EXEC_M 0x3F
#define LP5521_RUN_R 0x20
#define LP5521_RUN_G 0x08
#define LP5521_RUN_B 0x02
static inline void lp5521_wait_opmode_done(void)
{
/* operation mode change needs to be longer than 153 us */
usleep_range(200, 300);
}
static inline void lp5521_wait_enable_done(void)
{
/* it takes more 488 us to update ENABLE register */
usleep_range(500, 600);
}
static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
{
led->led_current = led_current;
lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
led_current);
}
static void lp5521_load_engine(struct lp55xx_chip *chip)
{
enum lp55xx_engine_index idx = chip->engine_idx;
u8 mask[] = {
[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
};
u8 val[] = {
[LP55XX_ENGINE_1] = LP5521_LOAD_R,
[LP55XX_ENGINE_2] = LP5521_LOAD_G,
[LP55XX_ENGINE_3] = LP5521_LOAD_B,
};
lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
lp5521_wait_opmode_done();
}
static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
{
lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
lp5521_wait_opmode_done();
}
static void lp5521_stop_engine(struct lp55xx_chip *chip)
{
enum lp55xx_engine_index idx = chip->engine_idx;
u8 mask[] = {
[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
};
lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
lp5521_wait_opmode_done();
}
static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
{
int ret;
u8 mode;
u8 exec;
/* stop engine */
if (!start) {
lp5521_stop_engine(chip);
lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
lp5521_wait_opmode_done();
return;
}
/*
* To run the engine,
* operation mode and enable register should updated at the same time
*/
ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
if (ret)
return;
ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
if (ret)
return;
/* change operation mode to RUN only when each engine is loading */
if (LP5521_R_IS_LOADING(mode)) {
mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
}
if (LP5521_G_IS_LOADING(mode)) {
mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
}
if (LP5521_B_IS_LOADING(mode)) {
mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
}
lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
lp5521_wait_opmode_done();
lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
lp5521_wait_enable_done();
}
static int lp5521_update_program_memory(struct lp55xx_chip *chip,
const u8 *data, size_t size)
{
enum lp55xx_engine_index idx = chip->engine_idx;
u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
u8 addr[] = {
[LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
[LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
[LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
};
unsigned cmd;
char c[3];
int nrchars;
int ret;
int offset = 0;
int i = 0;
while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
/* separate sscanfs because length is working only for %s */
ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
if (ret != 1)
goto err;
ret = sscanf(c, "%2x", &cmd);
if (ret != 1)
goto err;
pattern[i] = (u8)cmd;
offset += nrchars;
i++;
}
/* Each instruction is 16bit long. Check that length is even */
if (i % 2)
goto err;
for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
if (ret)
return -EINVAL;
}
return size;
err:
dev_err(&chip->cl->dev, "wrong pattern format\n");
return -EINVAL;
}
static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
{
const struct firmware *fw = chip->fw;
if (fw->size > LP5521_PROGRAM_LENGTH) {
dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
fw->size);
return;
}
/*
* Program momery sequence
* 1) set engine mode to "LOAD"
* 2) write firmware data into program memory
*/
lp5521_load_engine(chip);
lp5521_update_program_memory(chip, fw->data, fw->size);
}
static int lp5521_post_init_device(struct lp55xx_chip *chip)
{
int ret;
u8 val;
/*
* Make sure that the chip is reset by reading back the r channel
* current reg. This is dummy read is required on some platforms -
* otherwise further access to the R G B channels in the
* LP5521_REG_ENABLE register will not have any effect - strange!
*/
ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
if (ret) {
dev_err(&chip->cl->dev, "error in resetting chip\n");
return ret;
}
if (val != LP5521_REG_R_CURR_DEFAULT) {
dev_err(&chip->cl->dev,
"unexpected data in register (expected 0x%x got 0x%x)\n",
LP5521_REG_R_CURR_DEFAULT, val);
ret = -EINVAL;
return ret;
}
usleep_range(10000, 20000);
/* Set all PWMs to direct control mode */
ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
/* Update configuration for the clock setting */
val = LP5521_DEFAULT_CFG;
if (!lp55xx_is_extclk_used(chip))
val |= LP5521_CLK_INT;
ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
if (ret)
return ret;
/* Initialize all channels PWM to zero -> leds off */
lp55xx_write(chip, LP5521_REG_R_PWM, 0);
lp55xx_write(chip, LP5521_REG_G_PWM, 0);
lp55xx_write(chip, LP5521_REG_B_PWM, 0);
/* Set engines are set to run state when OP_MODE enables engines */
ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
if (ret)
return ret;
lp5521_wait_enable_done();
return 0;
}
static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
{
struct lp55xx_platform_data *pdata = chip->pdata;
int ret;
u8 status;
ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
if (ret < 0)
return ret;
if (pdata->clock_mode != LP55XX_CLOCK_EXT)
return 0;
/* Check that ext clock is really in use if requested */
if ((status & LP5521_EXT_CLK_USED) == 0)
return -EIO;
return 0;
}
static void lp5521_led_brightness_work(struct work_struct *work)
{
struct lp55xx_led *led = container_of(work, struct lp55xx_led,
brightness_work);
struct lp55xx_chip *chip = led->chip;
mutex_lock(&chip->lock);
lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
led->brightness);
mutex_unlock(&chip->lock);
}
static ssize_t show_engine_mode(struct device *dev,
struct device_attribute *attr,
char *buf, int nr)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
switch (mode) {
case LP55XX_ENGINE_RUN:
return sprintf(buf, "run\n");
case LP55XX_ENGINE_LOAD:
return sprintf(buf, "load\n");
case LP55XX_ENGINE_DISABLED:
default:
return sprintf(buf, "disabled\n");
}
}
show_mode(1)
show_mode(2)
show_mode(3)
static ssize_t store_engine_mode(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len, int nr)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
struct lp55xx_engine *engine = &chip->engines[nr - 1];
mutex_lock(&chip->lock);
chip->engine_idx = nr;
if (!strncmp(buf, "run", 3)) {
lp5521_run_engine(chip, true);
engine->mode = LP55XX_ENGINE_RUN;
} else if (!strncmp(buf, "load", 4)) {
lp5521_stop_engine(chip);
lp5521_load_engine(chip);
engine->mode = LP55XX_ENGINE_LOAD;
} else if (!strncmp(buf, "disabled", 8)) {
lp5521_stop_engine(chip);
engine->mode = LP55XX_ENGINE_DISABLED;
}
mutex_unlock(&chip->lock);
return len;
}
store_mode(1)
store_mode(2)
store_mode(3)
static ssize_t store_engine_load(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len, int nr)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
int ret;
mutex_lock(&chip->lock);
chip->engine_idx = nr;
lp5521_load_engine(chip);
ret = lp5521_update_program_memory(chip, buf, len);
mutex_unlock(&chip->lock);
return ret;
}
store_load(1)
store_load(2)
store_load(3)
static ssize_t lp5521_selftest(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
int ret;
mutex_lock(&chip->lock);
ret = lp5521_run_selftest(chip, buf);
mutex_unlock(&chip->lock);
return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
}
/* device attributes */
static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
static struct attribute *lp5521_attributes[] = {
&dev_attr_engine1_mode.attr,
&dev_attr_engine2_mode.attr,
&dev_attr_engine3_mode.attr,
&dev_attr_engine1_load.attr,
&dev_attr_engine2_load.attr,
&dev_attr_engine3_load.attr,
&dev_attr_selftest.attr,
NULL
};
static const struct attribute_group lp5521_group = {
.attrs = lp5521_attributes,
};
/* Chip specific configurations */
static struct lp55xx_device_config lp5521_cfg = {
.reset = {
.addr = LP5521_REG_RESET,
.val = LP5521_RESET,
},
.enable = {
.addr = LP5521_REG_ENABLE,
.val = LP5521_ENABLE_DEFAULT,
},
.max_channel = LP5521_MAX_LEDS,
.post_init_device = lp5521_post_init_device,
.brightness_work_fn = lp5521_led_brightness_work,
.set_led_current = lp5521_set_led_current,
.firmware_cb = lp5521_firmware_loaded,
.run_engine = lp5521_run_engine,
.dev_attr_group = &lp5521_group,
};
static int lp5521_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct lp55xx_chip *chip;
struct lp55xx_led *led;
struct lp55xx_platform_data *pdata;
struct device_node *np = client->dev.of_node;
if (!dev_get_platdata(&client->dev)) {
if (np) {
ret = lp55xx_of_populate_pdata(&client->dev, np);
if (ret < 0)
return ret;
} else {
dev_err(&client->dev, "no platform data\n");
return -EINVAL;
}
}
pdata = dev_get_platdata(&client->dev);
chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
led = devm_kzalloc(&client->dev,
sizeof(*led) * pdata->num_channels, GFP_KERNEL);
if (!led)
return -ENOMEM;
chip->cl = client;
chip->pdata = pdata;
chip->cfg = &lp5521_cfg;
mutex_init(&chip->lock);
i2c_set_clientdata(client, led);
ret = lp55xx_init_device(chip);
if (ret)
goto err_init;
dev_info(&client->dev, "%s programmable led chip found\n", id->name);
ret = lp55xx_register_leds(led, chip);
if (ret)
goto err_register_leds;
ret = lp55xx_register_sysfs(chip);
if (ret) {
dev_err(&client->dev, "registering sysfs failed\n");
goto err_register_sysfs;
}
return 0;
err_register_sysfs:
lp55xx_unregister_leds(led, chip);
err_register_leds:
lp55xx_deinit_device(chip);
err_init:
return ret;
}
static int lp5521_remove(struct i2c_client *client)
{
struct lp55xx_led *led = i2c_get_clientdata(client);
struct lp55xx_chip *chip = led->chip;
lp5521_stop_all_engines(chip);
lp55xx_unregister_sysfs(chip);
lp55xx_unregister_leds(led, chip);
lp55xx_deinit_device(chip);
return 0;
}
static const struct i2c_device_id lp5521_id[] = {
{ "lp5521", 0 }, /* Three channel chip */
{ }
};
MODULE_DEVICE_TABLE(i2c, lp5521_id);
#ifdef CONFIG_OF
static const struct of_device_id of_lp5521_leds_match[] = {
{ .compatible = "national,lp5521", },
{},
};
MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
#endif
static struct i2c_driver lp5521_driver = {
.driver = {
.name = "lp5521",
.of_match_table = of_match_ptr(of_lp5521_leds_match),
},
.probe = lp5521_probe,
.remove = lp5521_remove,
.id_table = lp5521_id,
};
module_i2c_driver(lp5521_driver);
MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5521 LED engine");
MODULE_LICENSE("GPL v2");