/*
* LP5521 LED chip driver.
*
*
*
*
* 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
/* Bits in 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 4 /* R out: 0 = CP, 1 = Vbat */
#define LP5521_CLK_SRC_EXT 0 /* Ext-clk source (CLK_32K) */
#define LP5521_CLK_INT 1 /* Internal clock */
#define LP5521_CLK_AUTO 2 /* Automatic clock selection */
/* Status */
#define LP5521_EXT_CLK_USED 0x08
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);
/* set mode only for this engine */
engine_state &= ~(engine->engine_mask);
mode &= engine->engine_mask;
engine_state |= mode;
ret |= lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
return ret;
}
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);
/* 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);
/* 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);
ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
return ret;
}
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;
lp5521_init_engine(chip);
/* Set all PWMs to direct control mode */
ret = lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
/* Enable auto-powersave, set charge pump to auto, red to battery */
ret |= lp5521_write(client, LP5521_REG_CONFIG,
LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
/* 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_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM |
LP5521_EXEC_RUN);
/* 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 && c