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linux/drivers/leds/leds-lp5521.c
Christian Marangi 4137d94fd8 leds: leds-lp55xx: Convert mutex lock/unlock to guard API 
Convert any entry of mutex lock/unlock to guard API and simplify code.
With the use of guard API, handling for selttest functions can be
greatly simplified.

Suggested-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Link: https://lore.kernel.org/r/20240626221520.2846-3-ansuelsmth@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
2024-07-11 12:46:25 +01:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* 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>
*/
#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.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_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_MASK 0x18 /* Charge pump mode */
#define LP5521_CP_MODE_SHIFT 3
#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)
/* 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
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_run_engine(struct lp55xx_chip *chip, bool start)
{
int ret;
/* stop engine */
if (!start) {
lp55xx_stop_engine(chip);
lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
lp5521_wait_opmode_done();
return;
}
ret = lp55xx_run_engine_common(chip);
if (!ret)
lp5521_wait_enable_done();
}
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);
if (ret)
return ret;
/* Update configuration for the clock setting */
val = LP5521_DEFAULT_CFG;
if (!lp55xx_is_extclk_used(chip))
val |= LP5521_CLK_INT;
val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;
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 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;
guard(mutex)(&chip->lock);
ret = lp5521_run_selftest(chip, buf);
return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
}
/* device attributes */
LP55XX_DEV_ATTR_ENGINE_MODE(1);
LP55XX_DEV_ATTR_ENGINE_MODE(2);
LP55XX_DEV_ATTR_ENGINE_MODE(3);
LP55XX_DEV_ATTR_ENGINE_LOAD(1);
LP55XX_DEV_ATTR_ENGINE_LOAD(2);
LP55XX_DEV_ATTR_ENGINE_LOAD(3);
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 = {
.reg_op_mode = {
.addr = LP5521_REG_OP_MODE,
},
.reg_exec = {
.addr = LP5521_REG_ENABLE,
},
.reset = {
.addr = LP5521_REG_RESET,
.val = LP5521_RESET,
},
.enable = {
.addr = LP5521_REG_ENABLE,
.val = LP5521_ENABLE_DEFAULT,
},
.prog_mem_base = {
.addr = LP5521_REG_R_PROG_MEM,
},
.reg_led_pwm_base = {
.addr = LP5521_REG_LED_PWM_BASE,
},
.reg_led_current_base = {
.addr = LP5521_REG_LED_CURRENT_BASE,
},
.max_channel = LP5521_MAX_LEDS,
.post_init_device = lp5521_post_init_device,
.brightness_fn = lp55xx_led_brightness,
.multicolor_brightness_fn = lp55xx_multicolor_brightness,
.set_led_current = lp55xx_set_led_current,
.firmware_cb = lp55xx_firmware_loaded_cb,
.run_engine = lp5521_run_engine,
.dev_attr_group = &lp5521_group,
};
static const struct i2c_device_id lp5521_id[] = {
{ "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */
{ }
};
MODULE_DEVICE_TABLE(i2c, lp5521_id);
static const struct of_device_id of_lp5521_leds_match[] = {
{ .compatible = "national,lp5521", .data = &lp5521_cfg, },
{},
};
MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
static struct i2c_driver lp5521_driver = {
.driver = {
.name = "lp5521",
.of_match_table = of_lp5521_leds_match,
},
.probe = lp55xx_probe,
.remove = lp55xx_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");
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