leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity
b548a34ba4
linux/drivers/leds/leds-lp5523.c
Linus Walleij 7542a04b15 leds: lp55xx: add support for Device Tree bindings 
This patch allows the lp5521 driver to be successfully probed and
initialised when Device Tree support is enabled.

Based on a patch by Gabriel Fernandez, rewritten in accordance
with review feedback.

Cc: Gabriel Fernandez <gabriel.fernandez@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-06-20 16:21:31 -07:00

527 lines
13 KiB
C
Raw Blame History

/*
* lp5523.c - LP5523 LED 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 "leds-lp55xx-common.h"
#define LP5523_PROGRAM_LENGTH 32
#define LP5523_MAX_LEDS 9
/* Registers */
#define LP5523_REG_ENABLE 0x00
#define LP5523_REG_OP_MODE 0x01
#define LP5523_REG_ENABLE_LEDS_MSB 0x04
#define LP5523_REG_ENABLE_LEDS_LSB 0x05
#define LP5523_REG_LED_PWM_BASE 0x16
#define LP5523_REG_LED_CURRENT_BASE 0x26
#define LP5523_REG_CONFIG 0x36
#define LP5523_REG_STATUS 0x3A
#define LP5523_REG_RESET 0x3D
#define LP5523_REG_LED_TEST_CTRL 0x41
#define LP5523_REG_LED_TEST_ADC 0x42
#define LP5523_REG_PROG_PAGE_SEL 0x4F
#define LP5523_REG_PROG_MEM 0x50
/* Bit description in registers */
#define LP5523_ENABLE 0x40
#define LP5523_AUTO_INC 0x40
#define LP5523_PWR_SAVE 0x20
#define LP5523_PWM_PWR_SAVE 0x04
#define LP5523_CP_AUTO 0x18
#define LP5523_AUTO_CLK 0x02
#define LP5523_EN_LEDTEST 0x80
#define LP5523_LEDTEST_DONE 0x80
#define LP5523_RESET 0xFF
#define LP5523_ADC_SHORTCIRC_LIM 80
#define LP5523_EXT_CLK_USED 0x08
/* Memory Page Selection */
#define LP5523_PAGE_ENG1 0
#define LP5523_PAGE_ENG2 1
#define LP5523_PAGE_ENG3 2
/* Program Memory Operations */
#define LP5523_MODE_ENG1_M 0x30 /* Operation Mode Register */
#define LP5523_MODE_ENG2_M 0x0C
#define LP5523_MODE_ENG3_M 0x03
#define LP5523_LOAD_ENG1 0x10
#define LP5523_LOAD_ENG2 0x04
#define LP5523_LOAD_ENG3 0x01
#define LP5523_ENG1_IS_LOADING(mode) \
((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
#define LP5523_ENG2_IS_LOADING(mode) \
((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
#define LP5523_ENG3_IS_LOADING(mode) \
((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
#define LP5523_EXEC_ENG1_M 0x30 /* Enable Register */
#define LP5523_EXEC_ENG2_M 0x0C
#define LP5523_EXEC_ENG3_M 0x03
#define LP5523_EXEC_M 0x3F
#define LP5523_RUN_ENG1 0x20
#define LP5523_RUN_ENG2 0x08
#define LP5523_RUN_ENG3 0x02
enum lp5523_chip_id {
LP5523,
LP55231,
};
static inline void lp5523_wait_opmode_done(void)
{
usleep_range(1000, 2000);
}
static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
{
led->led_current = led_current;
lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
led_current);
}
static int lp5523_post_init_device(struct lp55xx_chip *chip)
{
int ret;
ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
if (ret)
return ret;
/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
usleep_range(1000, 2000);
ret = lp55xx_write(chip, LP5523_REG_CONFIG,
LP5523_AUTO_INC | LP5523_PWR_SAVE |
LP5523_CP_AUTO | LP5523_AUTO_CLK |
LP5523_PWM_PWR_SAVE);
if (ret)
return ret;
/* turn on all leds */
ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
if (ret)
return ret;
return lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
}
static void lp5523_load_engine(struct lp55xx_chip *chip)
{
enum lp55xx_engine_index idx = chip->engine_idx;
u8 mask[] = {
[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
};
u8 val[] = {
[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
};
u8 page_sel[] = {
[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
};
lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
lp5523_wait_opmode_done();
lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
}
static void lp5523_stop_engine(struct lp55xx_chip *chip)
{
lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
lp5523_wait_opmode_done();
}
static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
{
int i;
for (i = 0; i < LP5523_MAX_LEDS; i++)
lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
}
static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
{
int ret;
u8 mode;
u8 exec;
/* stop engine */
if (!start) {
lp5523_stop_engine(chip);
lp5523_turn_off_channels(chip);
return;
}
/*
* To run the engine,
* operation mode and enable register should updated at the same time
*/
ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
if (ret)
return;
ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
if (ret)
return;
/* change operation mode to RUN only when each engine is loading */
if (LP5523_ENG1_IS_LOADING(mode)) {
mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
}
if (LP5523_ENG2_IS_LOADING(mode)) {
mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
}
if (LP5523_ENG3_IS_LOADING(mode)) {
mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
}
lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
lp5523_wait_opmode_done();
lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
}
static int lp5523_update_program_memory(struct lp55xx_chip *chip,
const u8 *data, size_t size)
{
u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
unsigned cmd;
char c[3];
int update_size;
int nrchars;
int offset = 0;
int ret;
int i;
/* clear program memory before updating */
for (i = 0; i < LP5523_PROGRAM_LENGTH; i++)
lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0);
i = 0;
while ((offset < size - 1) && (i < LP5523_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;
update_size = i;
for (i = 0; i < update_size; i++)
lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
return 0;
err:
dev_err(&chip->cl->dev, "wrong pattern format\n");
return -EINVAL;
}
static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
{
const struct firmware *fw = chip->fw;
if (fw->size > LP5523_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
*/
lp5523_load_engine(chip);
lp5523_update_program_memory(chip, fw->data, fw->size);
}
static ssize_t lp5523_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;
struct lp55xx_platform_data *pdata = chip->pdata;
int i, ret, pos = 0;
u8 status, adc, vdd;
mutex_lock(&chip->lock);
ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
if (ret < 0)
goto fail;
/* Check that ext clock is really in use if requested */
if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
if ((status & LP5523_EXT_CLK_USED) == 0)
goto fail;
}
/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
if (ret < 0)
goto fail;
if (!(status & LP5523_LEDTEST_DONE))
usleep_range(3000, 6000); /* Was not ready. Wait little bit */
ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
if (ret < 0)
goto fail;
vdd--; /* There may be some fluctuation in measurement */
for (i = 0; i < LP5523_MAX_LEDS; i++) {
/* Skip non-existing channels */
if (pdata->led_config[i].led_current == 0)
continue;
/* Set default current */
lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
pdata->led_config[i].led_current);
lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
/* let current stabilize 2 - 4ms before measurements start */
usleep_range(2000, 4000);
lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
LP5523_EN_LEDTEST | i);
/* ADC conversion time is 2.7 ms typically */
usleep_range(3000, 6000);
ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
if (ret < 0)
goto fail;
if (!(status & LP5523_LEDTEST_DONE))
usleep_range(3000, 6000);/* Was not ready. Wait. */
ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
if (ret < 0)
goto fail;
if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
pos += sprintf(buf + pos, "LED %d FAIL\n", i);
lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
/* Restore current */
lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
led->led_current);
led++;
}
if (pos == 0)
pos = sprintf(buf, "OK\n");
goto release_lock;
fail:
pos = sprintf(buf, "FAIL\n");
release_lock:
mutex_unlock(&chip->lock);
return pos;
}
static void lp5523_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, LP5523_REG_LED_PWM_BASE + led->chan_nr,
led->brightness);
mutex_unlock(&chip->lock);
}
static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
static struct attribute *lp5523_attributes[] = {
&dev_attr_selftest.attr,
NULL,
};
static const struct attribute_group lp5523_group = {
.attrs = lp5523_attributes,
};
/* Chip specific configurations */
static struct lp55xx_device_config lp5523_cfg = {
.reset = {
.addr = LP5523_REG_RESET,
.val = LP5523_RESET,
},
.enable = {
.addr = LP5523_REG_ENABLE,
.val = LP5523_ENABLE,
},
.max_channel = LP5523_MAX_LEDS,
.post_init_device = lp5523_post_init_device,
.brightness_work_fn = lp5523_led_brightness_work,
.set_led_current = lp5523_set_led_current,
.firmware_cb = lp5523_firmware_loaded,
.run_engine = lp5523_run_engine,
.dev_attr_group = &lp5523_group,
};
static int lp5523_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 (!client->dev.platform_data) {
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 = client->dev.platform_data;
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 = &lp5523_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 lp5523_remove(struct i2c_client *client)
{
struct lp55xx_led *led = i2c_get_clientdata(client);
struct lp55xx_chip *chip = led->chip;
lp5523_stop_engine(chip);
lp55xx_unregister_sysfs(chip);
lp55xx_unregister_leds(led, chip);
lp55xx_deinit_device(chip);
return 0;
}
static const struct i2c_device_id lp5523_id[] = {
{ "lp5523", LP5523 },
{ "lp55231", LP55231 },
{ "national,lp5523", 0 }, /* OF compatible */
{ }
};
MODULE_DEVICE_TABLE(i2c, lp5523_id);
static struct i2c_driver lp5523_driver = {
.driver = {
.name = "lp5523x",
},
.probe = lp5523_probe,
.remove = lp5523_remove,
.id_table = lp5523_id,
};
module_i2c_driver(lp5523_driver);
MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5523 LED engine");
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink