linux_dsm_epyc7002/drivers/leds/leds-lm355x.c
Johan Hovold 0d25376c32 leds: lm355x: fix attribute-creation race
Use the attribute groups of the led-class to create the indicator-LED
attributes during probe in order to avoid racing with userspace.

Note that the comment about the pattern attribute only being for LM3554
was incorrect and did not match the code (the original leds-lm3556
driver had the attribute before LM3554 support was added).

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-06-25 15:10:54 -07:00

572 lines
14 KiB
C

/*
* Simple driver for Texas Instruments LM355x LED Flash driver chip
* Copyright (C) 2012 Texas Instruments
*
* 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.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/fs.h>
#include <linux/regmap.h>
#include <linux/workqueue.h>
#include <linux/platform_data/leds-lm355x.h>
enum lm355x_type {
CHIP_LM3554 = 0,
CHIP_LM3556,
};
enum lm355x_regs {
REG_FLAG = 0,
REG_TORCH_CFG,
REG_TORCH_CTRL,
REG_STROBE_CFG,
REG_FLASH_CTRL,
REG_INDI_CFG,
REG_INDI_CTRL,
REG_OPMODE,
REG_MAX,
};
/* operation mode */
enum lm355x_mode {
MODE_SHDN = 0,
MODE_INDIC,
MODE_TORCH,
MODE_FLASH
};
/* register map info. */
struct lm355x_reg_data {
u8 regno;
u8 mask;
u8 shift;
};
struct lm355x_chip_data {
struct device *dev;
enum lm355x_type type;
struct led_classdev cdev_flash;
struct led_classdev cdev_torch;
struct led_classdev cdev_indicator;
struct work_struct work_flash;
struct work_struct work_torch;
struct work_struct work_indicator;
u8 br_flash;
u8 br_torch;
u8 br_indicator;
struct lm355x_platform_data *pdata;
struct regmap *regmap;
struct mutex lock;
unsigned int last_flag;
struct lm355x_reg_data *regs;
};
/* specific indicator function for lm3556 */
enum lm3556_indic_pulse_time {
PULSE_TIME_0_MS = 0,
PULSE_TIME_32_MS,
PULSE_TIME_64_MS,
PULSE_TIME_92_MS,
PULSE_TIME_128_MS,
PULSE_TIME_160_MS,
PULSE_TIME_196_MS,
PULSE_TIME_224_MS,
PULSE_TIME_256_MS,
PULSE_TIME_288_MS,
PULSE_TIME_320_MS,
PULSE_TIME_352_MS,
PULSE_TIME_384_MS,
PULSE_TIME_416_MS,
PULSE_TIME_448_MS,
PULSE_TIME_480_MS,
};
enum lm3556_indic_n_blank {
INDIC_N_BLANK_0 = 0,
INDIC_N_BLANK_1,
INDIC_N_BLANK_2,
INDIC_N_BLANK_3,
INDIC_N_BLANK_4,
INDIC_N_BLANK_5,
INDIC_N_BLANK_6,
INDIC_N_BLANK_7,
INDIC_N_BLANK_8,
INDIC_N_BLANK_9,
INDIC_N_BLANK_10,
INDIC_N_BLANK_11,
INDIC_N_BLANK_12,
INDIC_N_BLANK_13,
INDIC_N_BLANK_14,
INDIC_N_BLANK_15,
};
enum lm3556_indic_period {
INDIC_PERIOD_0 = 0,
INDIC_PERIOD_1,
INDIC_PERIOD_2,
INDIC_PERIOD_3,
INDIC_PERIOD_4,
INDIC_PERIOD_5,
INDIC_PERIOD_6,
INDIC_PERIOD_7,
};
#define INDIC_PATTERN_SIZE 4
struct indicator {
u8 blinking;
u8 period_cnt;
};
/* indicator pattern data only for lm3556 */
static struct indicator indicator_pattern[INDIC_PATTERN_SIZE] = {
[0] = {(INDIC_N_BLANK_1 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_1},
[1] = {(INDIC_N_BLANK_15 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_2},
[2] = {(INDIC_N_BLANK_10 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_4},
[3] = {(INDIC_N_BLANK_5 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_7},
};
static struct lm355x_reg_data lm3554_regs[REG_MAX] = {
[REG_FLAG] = {0xD0, 0xBF, 0},
[REG_TORCH_CFG] = {0xE0, 0x80, 7},
[REG_TORCH_CTRL] = {0xA0, 0x38, 3},
[REG_STROBE_CFG] = {0xE0, 0x04, 2},
[REG_FLASH_CTRL] = {0xB0, 0x78, 3},
[REG_INDI_CFG] = {0xE0, 0x08, 3},
[REG_INDI_CTRL] = {0xA0, 0xC0, 6},
[REG_OPMODE] = {0xA0, 0x03, 0},
};
static struct lm355x_reg_data lm3556_regs[REG_MAX] = {
[REG_FLAG] = {0x0B, 0xFF, 0},
[REG_TORCH_CFG] = {0x0A, 0x10, 4},
[REG_TORCH_CTRL] = {0x09, 0x70, 4},
[REG_STROBE_CFG] = {0x0A, 0x20, 5},
[REG_FLASH_CTRL] = {0x09, 0x0F, 0},
[REG_INDI_CFG] = {0xFF, 0xFF, 0},
[REG_INDI_CTRL] = {0x09, 0x70, 4},
[REG_OPMODE] = {0x0A, 0x03, 0},
};
static char lm355x_name[][I2C_NAME_SIZE] = {
[CHIP_LM3554] = LM3554_NAME,
[CHIP_LM3556] = LM3556_NAME,
};
/* chip initialize */
static int lm355x_chip_init(struct lm355x_chip_data *chip)
{
int ret;
unsigned int reg_val;
struct lm355x_platform_data *pdata = chip->pdata;
/* input and output pins configuration */
switch (chip->type) {
case CHIP_LM3554:
reg_val = pdata->pin_tx2 | pdata->ntc_pin;
ret = regmap_update_bits(chip->regmap, 0xE0, 0x28, reg_val);
if (ret < 0)
goto out;
reg_val = pdata->pass_mode;
ret = regmap_update_bits(chip->regmap, 0xA0, 0x04, reg_val);
if (ret < 0)
goto out;
break;
case CHIP_LM3556:
reg_val = pdata->pin_tx2 | pdata->ntc_pin | pdata->pass_mode;
ret = regmap_update_bits(chip->regmap, 0x0A, 0xC4, reg_val);
if (ret < 0)
goto out;
break;
default:
return -ENODATA;
}
return ret;
out:
dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
return ret;
}
/* chip control */
static void lm355x_control(struct lm355x_chip_data *chip,
u8 brightness, enum lm355x_mode opmode)
{
int ret;
unsigned int reg_val;
struct lm355x_platform_data *pdata = chip->pdata;
struct lm355x_reg_data *preg = chip->regs;
ret = regmap_read(chip->regmap, preg[REG_FLAG].regno, &chip->last_flag);
if (ret < 0)
goto out;
if (chip->last_flag & preg[REG_FLAG].mask)
dev_info(chip->dev, "%s Last FLAG is 0x%x\n",
lm355x_name[chip->type],
chip->last_flag & preg[REG_FLAG].mask);
/* brightness 0 means shutdown */
if (!brightness)
opmode = MODE_SHDN;
switch (opmode) {
case MODE_TORCH:
ret =
regmap_update_bits(chip->regmap, preg[REG_TORCH_CTRL].regno,
preg[REG_TORCH_CTRL].mask,
(brightness - 1)
<< preg[REG_TORCH_CTRL].shift);
if (ret < 0)
goto out;
if (pdata->pin_tx1 != LM355x_PIN_TORCH_DISABLE) {
ret =
regmap_update_bits(chip->regmap,
preg[REG_TORCH_CFG].regno,
preg[REG_TORCH_CFG].mask,
0x01 <<
preg[REG_TORCH_CFG].shift);
if (ret < 0)
goto out;
opmode = MODE_SHDN;
dev_info(chip->dev,
"torch brt is set - ext. torch pin mode\n");
}
break;
case MODE_FLASH:
ret =
regmap_update_bits(chip->regmap, preg[REG_FLASH_CTRL].regno,
preg[REG_FLASH_CTRL].mask,
(brightness - 1)
<< preg[REG_FLASH_CTRL].shift);
if (ret < 0)
goto out;
if (pdata->pin_strobe != LM355x_PIN_STROBE_DISABLE) {
if (chip->type == CHIP_LM3554)
reg_val = 0x00;
else
reg_val = 0x01;
ret =
regmap_update_bits(chip->regmap,
preg[REG_STROBE_CFG].regno,
preg[REG_STROBE_CFG].mask,
reg_val <<
preg[REG_STROBE_CFG].shift);
if (ret < 0)
goto out;
opmode = MODE_SHDN;
dev_info(chip->dev,
"flash brt is set - ext. strobe pin mode\n");
}
break;
case MODE_INDIC:
ret =
regmap_update_bits(chip->regmap, preg[REG_INDI_CTRL].regno,
preg[REG_INDI_CTRL].mask,
(brightness - 1)
<< preg[REG_INDI_CTRL].shift);
if (ret < 0)
goto out;
if (pdata->pin_tx2 != LM355x_PIN_TX_DISABLE) {
ret =
regmap_update_bits(chip->regmap,
preg[REG_INDI_CFG].regno,
preg[REG_INDI_CFG].mask,
0x01 <<
preg[REG_INDI_CFG].shift);
if (ret < 0)
goto out;
opmode = MODE_SHDN;
}
break;
case MODE_SHDN:
break;
default:
return;
}
/* operation mode control */
ret = regmap_update_bits(chip->regmap, preg[REG_OPMODE].regno,
preg[REG_OPMODE].mask,
opmode << preg[REG_OPMODE].shift);
if (ret < 0)
goto out;
return;
out:
dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
return;
}
/* torch */
static void lm355x_deferred_torch_brightness_set(struct work_struct *work)
{
struct lm355x_chip_data *chip =
container_of(work, struct lm355x_chip_data, work_torch);
mutex_lock(&chip->lock);
lm355x_control(chip, chip->br_torch, MODE_TORCH);
mutex_unlock(&chip->lock);
}
static void lm355x_torch_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct lm355x_chip_data *chip =
container_of(cdev, struct lm355x_chip_data, cdev_torch);
chip->br_torch = brightness;
schedule_work(&chip->work_torch);
}
/* flash */
static void lm355x_deferred_strobe_brightness_set(struct work_struct *work)
{
struct lm355x_chip_data *chip =
container_of(work, struct lm355x_chip_data, work_flash);
mutex_lock(&chip->lock);
lm355x_control(chip, chip->br_flash, MODE_FLASH);
mutex_unlock(&chip->lock);
}
static void lm355x_strobe_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct lm355x_chip_data *chip =
container_of(cdev, struct lm355x_chip_data, cdev_flash);
chip->br_flash = brightness;
schedule_work(&chip->work_flash);
}
/* indicator */
static void lm355x_deferred_indicator_brightness_set(struct work_struct *work)
{
struct lm355x_chip_data *chip =
container_of(work, struct lm355x_chip_data, work_indicator);
mutex_lock(&chip->lock);
lm355x_control(chip, chip->br_indicator, MODE_INDIC);
mutex_unlock(&chip->lock);
}
static void lm355x_indicator_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct lm355x_chip_data *chip =
container_of(cdev, struct lm355x_chip_data, cdev_indicator);
chip->br_indicator = brightness;
schedule_work(&chip->work_indicator);
}
/* indicator pattern only for lm3556*/
static ssize_t lm3556_indicator_pattern_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
ssize_t ret;
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct lm355x_chip_data *chip =
container_of(led_cdev, struct lm355x_chip_data, cdev_indicator);
unsigned int state;
ret = kstrtouint(buf, 10, &state);
if (ret)
goto out;
if (state > INDIC_PATTERN_SIZE - 1)
state = INDIC_PATTERN_SIZE - 1;
ret = regmap_write(chip->regmap, 0x04,
indicator_pattern[state].blinking);
if (ret < 0)
goto out;
ret = regmap_write(chip->regmap, 0x05,
indicator_pattern[state].period_cnt);
if (ret < 0)
goto out;
return size;
out:
dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
return ret;
}
static DEVICE_ATTR(pattern, S_IWUSR, NULL, lm3556_indicator_pattern_store);
static struct attribute *lm355x_indicator_attrs[] = {
&dev_attr_pattern.attr,
NULL
};
ATTRIBUTE_GROUPS(lm355x_indicator);
static const struct regmap_config lm355x_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0xFF,
};
/* module initialize */
static int lm355x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct lm355x_platform_data *pdata = dev_get_platdata(&client->dev);
struct lm355x_chip_data *chip;
int err;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "i2c functionality check fail.\n");
return -EOPNOTSUPP;
}
if (pdata == NULL) {
dev_err(&client->dev, "needs Platform Data.\n");
return -ENODATA;
}
chip = devm_kzalloc(&client->dev,
sizeof(struct lm355x_chip_data), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = &client->dev;
chip->type = id->driver_data;
switch (id->driver_data) {
case CHIP_LM3554:
chip->regs = lm3554_regs;
break;
case CHIP_LM3556:
chip->regs = lm3556_regs;
break;
default:
return -ENOSYS;
}
chip->pdata = pdata;
chip->regmap = devm_regmap_init_i2c(client, &lm355x_regmap);
if (IS_ERR(chip->regmap)) {
err = PTR_ERR(chip->regmap);
dev_err(&client->dev,
"Failed to allocate register map: %d\n", err);
return err;
}
mutex_init(&chip->lock);
i2c_set_clientdata(client, chip);
err = lm355x_chip_init(chip);
if (err < 0)
goto err_out;
/* flash */
INIT_WORK(&chip->work_flash, lm355x_deferred_strobe_brightness_set);
chip->cdev_flash.name = "flash";
chip->cdev_flash.max_brightness = 16;
chip->cdev_flash.brightness_set = lm355x_strobe_brightness_set;
chip->cdev_flash.default_trigger = "flash";
err = led_classdev_register((struct device *)
&client->dev, &chip->cdev_flash);
if (err < 0)
goto err_out;
/* torch */
INIT_WORK(&chip->work_torch, lm355x_deferred_torch_brightness_set);
chip->cdev_torch.name = "torch";
chip->cdev_torch.max_brightness = 8;
chip->cdev_torch.brightness_set = lm355x_torch_brightness_set;
chip->cdev_torch.default_trigger = "torch";
err = led_classdev_register((struct device *)
&client->dev, &chip->cdev_torch);
if (err < 0)
goto err_create_torch_file;
/* indicator */
INIT_WORK(&chip->work_indicator,
lm355x_deferred_indicator_brightness_set);
chip->cdev_indicator.name = "indicator";
if (id->driver_data == CHIP_LM3554)
chip->cdev_indicator.max_brightness = 4;
else
chip->cdev_indicator.max_brightness = 8;
chip->cdev_indicator.brightness_set = lm355x_indicator_brightness_set;
/* indicator pattern control only for LM3556 */
if (id->driver_data == CHIP_LM3556)
chip->cdev_indicator.groups = lm355x_indicator_groups;
err = led_classdev_register((struct device *)
&client->dev, &chip->cdev_indicator);
if (err < 0)
goto err_create_indicator_file;
dev_info(&client->dev, "%s is initialized\n",
lm355x_name[id->driver_data]);
return 0;
err_create_indicator_file:
led_classdev_unregister(&chip->cdev_torch);
err_create_torch_file:
led_classdev_unregister(&chip->cdev_flash);
err_out:
return err;
}
static int lm355x_remove(struct i2c_client *client)
{
struct lm355x_chip_data *chip = i2c_get_clientdata(client);
struct lm355x_reg_data *preg = chip->regs;
regmap_write(chip->regmap, preg[REG_OPMODE].regno, 0);
led_classdev_unregister(&chip->cdev_indicator);
flush_work(&chip->work_indicator);
led_classdev_unregister(&chip->cdev_torch);
flush_work(&chip->work_torch);
led_classdev_unregister(&chip->cdev_flash);
flush_work(&chip->work_flash);
dev_info(&client->dev, "%s is removed\n", lm355x_name[chip->type]);
return 0;
}
static const struct i2c_device_id lm355x_id[] = {
{LM3554_NAME, CHIP_LM3554},
{LM3556_NAME, CHIP_LM3556},
{}
};
MODULE_DEVICE_TABLE(i2c, lm355x_id);
static struct i2c_driver lm355x_i2c_driver = {
.driver = {
.name = LM355x_NAME,
.owner = THIS_MODULE,
.pm = NULL,
},
.probe = lm355x_probe,
.remove = lm355x_remove,
.id_table = lm355x_id,
};
module_i2c_driver(lm355x_i2c_driver);
MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM355x");
MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
MODULE_LICENSE("GPL v2");