- 根目录:
- drivers
- leds
- leds-lp5521.c
/*
* LP5521 LED chip driver.
*
* Copyright (C) 2010 Nokia Corporation
*
* Contact: Samu Onkalo <samu.p.onkalo@nokia.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/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/ctype.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/leds.h>
#include <linux/leds-lp5521.h>
#include <linux/workqueue.h>
#include <linux/slab.h>
#define LP5521_PROGRAM_LENGTH 32 /* in bytes */
#define LP5521_MAX_LEDS 3 /* Maximum number of LEDs */
#define LP5521_MAX_ENGINES 3 /* Maximum number of engines */
#define LP5521_ENG_MASK_BASE 0x30 /* 00110000 */
#define LP5521_ENG_STATUS_MASK 0x07 /* 00000111 */
#define LP5521_CMD_LOAD 0x15 /* 00010101 */
#define LP5521_CMD_RUN 0x2a /* 00101010 */
#define LP5521_CMD_DIRECT 0x3f /* 00111111 */
#define LP5521_CMD_DISABLED 0x00 /* 00000000 */
/* 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_R_CHANNEL_PC 0x09
#define LP5521_REG_G_CHANNEL_PC 0x0A
#define LP5521_REG_B_CHANNEL_PC 0x0B
#define LP5521_REG_STATUS 0x0C
#define LP5521_REG_RESET 0x0D
#define LP5521_REG_GPO 0x0E
#define LP5521_REG_R_PROG_MEM 0x10
#define LP5521_REG_G_PROG_MEM 0x30
#define LP5521_REG_B_PROG_MEM 0x50
#define LP5521_PROG_MEM_BASE LP5521_REG_R_PROG_MEM
#define LP5521_PROG_MEM_SIZE 0x20
/* 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)
/* Status */
#define LP5521_EXT_CLK_USED 0x08
/* default R channel current register value */
#define LP5521_REG_R_CURR_DEFAULT 0xAF
/* Pattern Mode */
#define PATTERN_OFF 0
struct lp5521_engine {
int id;
u8 mode;
u8 prog_page;
u8 engine_mask;
};
struct lp5521_led {
int id;
u8 chan_nr;
u8 led_current;
u8 max_current;
struct led_classdev cdev;
struct work_struct brightness_work;
u8 brightness;
};
struct lp5521_chip {
struct lp5521_platform_data *pdata;
struct mutex lock; /* Serialize control */
struct i2c_client *client;
struct lp5521_engine engines[LP5521_MAX_ENGINES];
struct lp5521_led leds[LP5521_MAX_LEDS];
u8 num_channels;
u8 num_leds;
};
static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
{
return container_of(cdev, struct lp5521_led, cdev);
}
static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
{
return container_of(engine, struct lp5521_chip,
engines[engine->id - 1]);
}
static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
{
return container_of(led, struct lp5521_chip,
leds[led->id]);
}
static void lp5521_led_brightness_work(struct work_struct *work);
static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
{
return i2c_smbus_write_byte_data(client, reg, value);
}
static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
{
s32 ret;
ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0)
return -EIO;
*buf = ret;
return 0;
}
static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
{
struct lp5521_chip *chip = engine_to_lp5521(engine);
struct i2c_client *client = chip->client;
int ret;
u8 engine_state;
/* Only transition between RUN and DIRECT mode are handled here */
if (mode == LP5521_CMD_LOAD)
return 0;
if (mode == LP5521_CMD_DISABLED)
mode = LP5521_CMD_DIRECT;
ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
if (ret < 0)
return ret;
/* set mode only for this engine */
engine_state &= ~(engine->engine_mask);
mode &= engine->engine_mask;
engine_state |= mode;
return lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
}
static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
{
struct lp5521_chip *chip = engine_to_lp5521(eng);
struct i2c_client *client = chip->client;
int ret;
int addr;
u8 mode;
/* move current engine to direct mode and remember the state */
ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
if (ret)
return ret;
/* Mode change requires min 500 us delay. 1 - 2 ms with margin */
usleep_range(1000, 2000);
ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
if (ret)
return ret;
/* For loading, all the engines to load mode */
lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
/* Mode change requires min 500 us delay. 1 - 2 ms with margin */
usleep_range(1000, 2000);
lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
/* Mode change requires min 500 us delay. 1 - 2 ms with margin */
usleep_range(1000, 2000);
addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
i2c_smbus_write_i2c_block_data(client,
addr,
LP5521_PROG_MEM_SIZE,
pattern);
return lp5521_write(client, LP5521_REG_OP_MODE, mode);
}
static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
{
return lp5521_write(chip->client,
LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
curr);
}
static void lp5521_init_engine(struct lp5521_chip *chip)
{
int i;
for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
chip->engines[i].id = i + 1;
chip->engines[i].engine_mask = LP5521_ENG_MASK_BASE >> (i * 2);
chip->engines[i].prog_page = i;
}
}
static int lp5521_configure(struct i2c_client *client)
{
struct lp5521_chip *chip = i2c_get_clientdata(client);
int ret;
u8 cfg;
lp5521_init_engine(chip);
/* Set all PWMs to direct control mode */
ret = lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
cfg = chip->pdata->update_config ?
: (LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
ret |= lp5521_write(client, LP5521_REG_CONFIG, cfg);
/* Initialize all channels PWM to zero -> leds off */
ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
/* Set engines are set to run state when OP_MODE enables engines */
ret |= lp5521_write(client, LP5521_REG_ENABLE,
LP5521_ENABLE_RUN_PROGRAM);
/* enable takes 500us. 1 - 2 ms leaves some margin */
usleep_range(1000, 2000);
return ret;
}
static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
{
int ret;
u8 status;
ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
if (ret < 0)
return ret;
/* Check that ext clock is really in use if requested */
if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
if ((status & LP5521_EXT_CLK_USED) == 0)
return -EIO;
return 0;
}
static void lp5521_set_brightness(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct lp5521_led *led = cdev_to_led(cdev);
led->brightness = (u8)brightness;
schedule_work(&led->brightness_work);
}
static void lp5521_led_brightness_work(struct work_struct *work)
{
struct lp5521_led *led = container_of(work,
struct lp5521_led,
brightness_work);
struct lp5521_chip *chip = led_to_lp5521(led);
struct i2c_client *client = chip->client;
mutex_lock(&chip->lock);
lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
led->brightness);
mutex_unlock(&chip->lock);
}
/* Detect the chip by setting its ENABLE register and reading it back. */
static int lp5521_detect(struct i2c_client *client)
{
int ret;
u8 buf;
ret = lp5521_write(client, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
if (ret)
return ret;
/* enable takes 500us. 1 - 2 ms leaves some margin */
usleep_range(1000, 2000);
ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
if (ret)
return ret;
if (buf != LP5521_ENABLE_DEFAULT)
return -ENODEV;
return 0;
}
/* Set engine mode and create appropriate sysfs attributes, if required. */
static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
{
int ret = 0;
/* if in that mode already do nothing, except for run */
if (mode == engine->mode && mode != LP5521_CMD_RUN)
return 0;
if (mode == LP5521_CMD_RUN) {
ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
} else if (mode == LP5521_CMD_LOAD) {
lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
} else if (mode == LP5521_CMD_DISABLED) {
lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
}
engine->mode = mode;
return ret;
}
static int lp5521_do_store_load(struct lp5521_engine *engine,
const char *buf, size_t len)
{
struct lp5521_chip *chip = engine_to_lp5521(engine);
struct i2c_client *client = chip->client;
int ret, nrchars, offset = 0, i = 0;
char c[3];
unsigned cmd;
u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
/* separate sscanfs because length is working only for %s */
ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
if (ret != 2)
goto fail;
ret = sscanf(c, "%2x", &cmd);
if (ret != 1)
goto fail;
pattern[i] = (u8)cmd;
offset += nrchars;
i++;
}
/* Each instruction is 16bit long. Check that length is even */
if (i % 2)
goto fail;
mutex_lock(&chip->lock);
if (engine->mode == LP5521_CMD_LOAD)
ret = lp5521_load_program(engine, pattern);
else
ret = -EINVAL;
mutex_unlock(&chip->lock);
if (ret) {
dev_err(&client->dev, "failed loading pattern\n");
return ret;
}
return len;
fail:
dev_err(&client->dev, "wrong pattern format\n");
return -EINVAL;
}
static ssize_t store_engine_load(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len, int nr)
{
struct i2c_client *client = to_i2c_client(dev);
struct lp5521_chip *chip = i2c_get_clientdata(client);
return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
}
#define store_load(nr) \
static ssize_t store_engine##nr##_load(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t len) \
{ \
return store_engine_load(dev, attr, buf, len, nr); \
}
store_load(1)
store_load(2)
store_load(3)
static ssize_t show_engine_mode(struct device *dev,
struct device_attribute *attr,
char *buf, int nr)
{
struct i2c_client *client = to_i2c_client(dev);
struct lp5521_chip *chip = i2c_get_clientdata(client);
switch (chip->engines[nr - 1].mode) {
case LP5521_CMD_RUN:
return sprintf(buf, "run\n");
case LP5521_CMD_LOAD:
return sprintf(buf, "load\n");
case LP5521_CMD_DISABLED:
return sprintf(buf, "disabled\n");
default:
return sprintf(buf, "disabled\n");
}
}
#define show_mode(nr) \
static ssize_t show_engine##nr##_mode(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
return show_engine_mode(dev, attr, buf, nr); \
}
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 i2c_client *client = to_i2c_client(dev);
struct lp5521_chip *chip = i2c_get_clientdata(client);
struct lp5521_engine *engine = &chip->engines[nr - 1];
mutex_lock(&chip->lock);
if (!strncmp(buf, "run", 3))
lp5521_set_mode(engine, LP5521_CMD_RUN);
else if (!strncmp(buf, "load", 4))
lp5521_set_mode(engine, LP5521_CMD_LOAD);
else if (!strncmp(buf, "disabled", 8))
lp5521_set_mode(engine, LP5521_CMD_DISABLED);
mutex_unlock(&chip->lock);
return len;
}
#define store_mode(nr) \
static ssize_t store_engine##nr##_mode(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t len) \
{ \
return store_engine_mode(dev, attr, buf, len, nr); \
}
store_mode(1)
store_mode(2)
store_mode(3)
static ssize_t show_max_current(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct lp5521_led *led = cdev_to_led(led_cdev);
return sprintf(buf, "%d\n", led->max_current);
}
static ssize_t show_current(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct lp5521_led *led = cdev_to_led(led_cdev);
return sprintf(buf, "%d\n", led->led_current);
}
static ssize_t store_current(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct lp5521_led *led = cdev_to_led(led_cdev);
struct lp5521_chip *chip = led_to_lp5521(led);
ssize_t ret;
unsigned long curr;
if (kstrtoul(buf, 0, &curr))
return -EINVAL;
if (curr > led->max_current)
return -EINVAL;
mutex_lock(&chip->lock);
ret = lp5521_set_led_current(chip, led->id, curr);
mutex_unlock(&chip->lock);
if (ret < 0)
return ret;
led->led_current = (u8)curr;
return len;
}
static ssize_t lp5521_selftest(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct lp5521_chip *chip = i2c_get_clientdata(client);
int ret;
mutex_lock(&chip->lock);
ret = lp5521_run_selftest(chip, buf);
mutex_unlock(&chip->lock);
return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
}
static void lp5521_clear_program_memory(struct i2c_client *cl)
{
int i;
u8 rgb_mem[] = {
LP5521_REG_R_PROG_MEM,
LP5521_REG_G_PROG_MEM,
LP5521_REG_B_PROG_MEM,
};
for (i = 0; i < ARRAY_SIZE(rgb_mem); i++) {
lp5521_write(cl, rgb_mem[i], 0);
lp5521_write(cl, rgb_mem[i] + 1, 0);
}
}
static void lp5521_write_program_memory(struct i2c_client *cl,
u8 base, u8 *rgb, int size)
{
int i;
if (!rgb || size <= 0)
return;
for (i = 0; i < size; i++)
lp5521_write(cl, base + i, *(rgb + i));
lp5521_write(cl, base + i, 0);
lp5521_write(cl, base + i + 1, 0);
}
static inline struct lp5521_led_pattern *lp5521_get_pattern
(struct lp5521_chip *chip, u8 offset)
{
struct lp5521_led_pattern *ptn;
ptn = chip->pdata->patterns + (offset - 1);
return ptn;
}
static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip)
{
struct lp5521_led_pattern *ptn;
struct i2c_client *cl = chip->client;
int num_patterns = chip->pdata->num_patterns;
if (mode > num_patterns || !(chip->pdata->patterns))
return;
if (mode == PATTERN_OFF) {
lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
usleep_range(1000, 2000);
lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
} else {
ptn = lp5521_get_pattern(chip, mode);
if (!ptn)
return;
lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
usleep_range(1000, 2000);
lp5521_clear_program_memory(cl);
lp5521_write_program_memory(cl, LP5521_REG_R_PROG_MEM,
ptn->r, ptn->size_r);
lp5521_write_program_memory(cl, LP5521_REG_G_PROG_MEM,
ptn->g, ptn->size_g);
lp5521_write_program_memory(cl, LP5521_REG_B_PROG_MEM,
ptn->b, ptn->size_b);
lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_RUN);
usleep_range(1000, 2000);
lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
}
}
static ssize_t store_led_pattern(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct lp5521_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
unsigned long val;
int ret;
ret = strict_strtoul(buf, 16, &val);
if (ret)
return ret;
lp5521_run_led_pattern(val, chip);
return len;
}
/* led class device attributes */
static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
static struct attribute *lp5521_led_attributes[] = {
&dev_attr_led_current.attr,
&dev_attr_max_current.attr,
NULL,
};
static struct attribute_group lp5521_led_attribute_group = {
.attrs = lp5521_led_attributes
};
/* device attributes */
static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
show_engine1_mode, store_engine1_mode);
static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
show_engine2_mode, store_engine2_mode);
static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
show_engine3_mode, store_engine3_mode);
static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
static DEVICE_ATTR(led_pattern, S_IWUSR, NULL, store_led_pattern);
static struct attribute *lp5521_attributes[] = {
&dev_attr_engine1_mode.attr,
&dev_attr_engine2_mode.attr,
&dev_attr_engine3_mode.attr,
&dev_attr_selftest.attr,
&dev_attr_engine1_load.attr,
&dev_attr_engine2_load.attr,
&dev_attr_engine3_load.attr,
&dev_attr_led_pattern.attr,
NULL
};
static const struct attribute_group lp5521_group = {
.attrs = lp5521_attributes,
};
static int lp5521_register_sysfs(struct i2c_client *client)
{
struct device *dev = &client->dev;
return sysfs_create_group(&dev->kobj, &lp5521_group);
}
static void lp5521_unregister_sysfs(struct i2c_client *client)
{
struct lp5521_chip *chip = i2c_get_clientdata(client);
struct device *dev = &client->dev;
int i;
sysfs_remove_group(&dev->kobj, &lp5521_group);
for (i = 0; i < chip->num_leds; i++)
sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
&lp5521_led_attribute_group);
}
static int __devinit lp5521_init_led(struct lp5521_led *led,
struct i2c_client *client,
int chan, struct lp5521_platform_data *pdata)
{
struct device *dev = &client->dev;
char name[32];
int res;
if (chan >= LP5521_MAX_LEDS)
return -EINVAL;
if (pdata->led_config[chan].led_current == 0)
return 0;
led->led_current = pdata->led_config[chan].led_current;
led->max_current = pdata->led_config[chan].max_current;
led->chan_nr = pdata->led_config[chan].chan_nr;
if (led->chan_nr >= LP5521_MAX_LEDS) {
dev_err(dev, "Use channel numbers between 0 and %d\n",
LP5521_MAX_LEDS - 1);
return -EINVAL;
}
led->cdev.brightness_set = lp5521_set_brightness;
if (pdata->led_config[chan].name) {
led->cdev.name = pdata->led_config[chan].name;
} else {
snprintf(name, sizeof(name), "%s:channel%d",
pdata->label ?: client->name, chan);
led->cdev.name = name;
}
res = led_classdev_register(dev, &led->cdev);
if (res < 0) {
dev_err(dev, "couldn't register led on channel %d\n", chan);
return res;
}
res = sysfs_create_group(&led->cdev.dev->kobj,
&lp5521_led_attribute_group);
if (res < 0) {
dev_err(dev, "couldn't register current attribute\n");
led_classdev_unregister(&led->cdev);
return res;
}
return 0;
}
static int __devinit lp5521_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct lp5521_chip *chip;
struct lp5521_platform_data *pdata;
int ret, i, led;
u8 buf;
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
i2c_set_clientdata(client, chip);
chip->client = client;
pdata = client->dev.platform_data;
if (!pdata) {
dev_err(&client->dev, "no platform data\n");
ret = -EINVAL;
goto fail1;
}
mutex_init(&chip->lock);
chip->pdata = pdata;
if (pdata->setup_resources) {
ret = pdata->setup_resources();
if (ret < 0)
goto fail1;
}
if (pdata->enable) {
pdata->enable(0);
usleep_range(1000, 2000); /* Keep enable down at least 1ms */
pdata->enable(1);
usleep_range(1000, 2000); /* 500us abs min. */
}
lp5521_write(client, LP5521_REG_RESET, 0xff);
usleep_range(10000, 20000); /*
* Exact value is not available. 10 - 20ms
* appears to be enough for reset.
*/
/*
* 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 = lp5521_read(client, LP5521_REG_R_CURRENT, &buf);
if (ret || buf != LP5521_REG_R_CURR_DEFAULT) {
dev_err(&client->dev, "error in resetting chip\n");
goto fail2;
}
usleep_range(10000, 20000);
ret = lp5521_detect(client);
if (ret) {
dev_err(&client->dev, "Chip not found\n");
goto fail2;
}
dev_info(&client->dev, "%s programmable led chip found\n", id->name);
ret = lp5521_configure(client);
if (ret < 0) {
dev_err(&client->dev, "error configuring chip\n");
goto fail2;
}
/* Initialize leds */
chip->num_channels = pdata->num_channels;
chip->num_leds = 0;
led = 0;
for (i = 0; i < pdata->num_channels; i++) {
/* Do not initialize channels that are not connected */
if (pdata->led_config[i].led_current == 0)
continue;
ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
if (ret) {
dev_err(&client->dev, "error initializing leds\n");
goto fail3;
}
chip->num_leds++;
chip->leds[led].id = led;
/* Set initial LED current */
lp5521_set_led_current(chip, led,
chip->leds[led].led_current);
INIT_WORK(&(chip->leds[led].brightness_work),
lp5521_led_brightness_work);
led++;
}
ret = lp5521_register_sysfs(client);
if (ret) {
dev_err(&client->dev, "registering sysfs failed\n");
goto fail3;
}
return ret;
fail3:
for (i = 0; i < chip->num_leds; i++) {
led_classdev_unregister(&chip->leds[i].cdev);
cancel_work_sync(&chip->leds[i].brightness_work);
}
fail2:
if (pdata->enable)
pdata->enable(0);
if (pdata->release_resources)
pdata->release_resources();
fail1:
kfree(chip);
return ret;
}
static int __devexit lp5521_remove(struct i2c_client *client)
{
struct lp5521_chip *chip = i2c_get_clientdata(client);
int i;
lp5521_run_led_pattern(PATTERN_OFF, chip);
lp5521_unregister_sysfs(client);
for (i = 0; i < chip->num_leds; i++) {
led_classdev_unregister(&chip->leds[i].cdev);
cancel_work_sync(&chip->leds[i].brightness_work);
}
if (chip->pdata->enable)
chip->pdata->enable(0);
if (chip->pdata->release_resources)
chip->pdata->release_resources();
kfree(chip);
return 0;
}
static const struct i2c_device_id lp5521_id[] = {
{ "lp5521", 0 }, /* Three channel chip */
{ }
};
MODULE_DEVICE_TABLE(i2c, lp5521_id);
static struct i2c_driver lp5521_driver = {
.driver = {
.name = "lp5521",
},
.probe = lp5521_probe,
.remove = __devexit_p(lp5521_remove),
.id_table = lp5521_id,
};
module_i2c_driver(lp5521_driver);
MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
MODULE_DESCRIPTION("LP5521 LED engine");
MODULE_LICENSE("GPL v2");