linux/drivers/leds/leds-lp8501.c
Uwe Kleine-König ed5c2f5fd1 i2c: Make remove callback return void
The value returned by an i2c driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/*
Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5
Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860
Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b
Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes
Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power
Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-16 12:46:26 +02:00

405 lines
9.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* TI LP8501 9 channel LED Driver
*
* Copyright (C) 2013 Texas Instruments
*
* Author: Milo(Woogyom) Kim <milo.kim@ti.com>
*/
#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/of.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include "leds-lp55xx-common.h"
#define LP8501_PROGRAM_LENGTH 32
#define LP8501_MAX_LEDS 9
/* Registers */
#define LP8501_REG_ENABLE 0x00
#define LP8501_ENABLE BIT(6)
#define LP8501_EXEC_M 0x3F
#define LP8501_EXEC_ENG1_M 0x30
#define LP8501_EXEC_ENG2_M 0x0C
#define LP8501_EXEC_ENG3_M 0x03
#define LP8501_RUN_ENG1 0x20
#define LP8501_RUN_ENG2 0x08
#define LP8501_RUN_ENG3 0x02
#define LP8501_REG_OP_MODE 0x01
#define LP8501_MODE_ENG1_M 0x30
#define LP8501_MODE_ENG2_M 0x0C
#define LP8501_MODE_ENG3_M 0x03
#define LP8501_LOAD_ENG1 0x10
#define LP8501_LOAD_ENG2 0x04
#define LP8501_LOAD_ENG3 0x01
#define LP8501_REG_PWR_CONFIG 0x05
#define LP8501_PWR_CONFIG_M 0x03
#define LP8501_REG_LED_PWM_BASE 0x16
#define LP8501_REG_LED_CURRENT_BASE 0x26
#define LP8501_REG_CONFIG 0x36
#define LP8501_PWM_PSAVE BIT(7)
#define LP8501_AUTO_INC BIT(6)
#define LP8501_PWR_SAVE BIT(5)
#define LP8501_CP_AUTO 0x18
#define LP8501_INT_CLK BIT(0)
#define LP8501_DEFAULT_CFG \
(LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO)
#define LP8501_REG_RESET 0x3D
#define LP8501_RESET 0xFF
#define LP8501_REG_PROG_PAGE_SEL 0x4F
#define LP8501_PAGE_ENG1 0
#define LP8501_PAGE_ENG2 1
#define LP8501_PAGE_ENG3 2
#define LP8501_REG_PROG_MEM 0x50
#define LP8501_ENG1_IS_LOADING(mode) \
((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1)
#define LP8501_ENG2_IS_LOADING(mode) \
((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2)
#define LP8501_ENG3_IS_LOADING(mode) \
((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3)
static inline void lp8501_wait_opmode_done(void)
{
usleep_range(1000, 2000);
}
static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current)
{
led->led_current = led_current;
lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr,
led_current);
}
static int lp8501_post_init_device(struct lp55xx_chip *chip)
{
int ret;
u8 val = LP8501_DEFAULT_CFG;
ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE);
if (ret)
return ret;
/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
usleep_range(1000, 2000);
if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT)
val |= LP8501_INT_CLK;
ret = lp55xx_write(chip, LP8501_REG_CONFIG, val);
if (ret)
return ret;
/* Power selection for each output */
return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG,
LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel);
}
static void lp8501_load_engine(struct lp55xx_chip *chip)
{
enum lp55xx_engine_index idx = chip->engine_idx;
static const u8 mask[] = {
[LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M,
[LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M,
[LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M,
};
static const u8 val[] = {
[LP55XX_ENGINE_1] = LP8501_LOAD_ENG1,
[LP55XX_ENGINE_2] = LP8501_LOAD_ENG2,
[LP55XX_ENGINE_3] = LP8501_LOAD_ENG3,
};
static const u8 page_sel[] = {
[LP55XX_ENGINE_1] = LP8501_PAGE_ENG1,
[LP55XX_ENGINE_2] = LP8501_PAGE_ENG2,
[LP55XX_ENGINE_3] = LP8501_PAGE_ENG3,
};
lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]);
lp8501_wait_opmode_done();
lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]);
}
static void lp8501_stop_engine(struct lp55xx_chip *chip)
{
lp55xx_write(chip, LP8501_REG_OP_MODE, 0);
lp8501_wait_opmode_done();
}
static void lp8501_turn_off_channels(struct lp55xx_chip *chip)
{
int i;
for (i = 0; i < LP8501_MAX_LEDS; i++)
lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0);
}
static void lp8501_run_engine(struct lp55xx_chip *chip, bool start)
{
int ret;
u8 mode;
u8 exec;
/* stop engine */
if (!start) {
lp8501_stop_engine(chip);
lp8501_turn_off_channels(chip);
return;
}
/*
* To run the engine,
* operation mode and enable register should updated at the same time
*/
ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode);
if (ret)
return;
ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec);
if (ret)
return;
/* change operation mode to RUN only when each engine is loading */
if (LP8501_ENG1_IS_LOADING(mode)) {
mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1;
exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1;
}
if (LP8501_ENG2_IS_LOADING(mode)) {
mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2;
exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2;
}
if (LP8501_ENG3_IS_LOADING(mode)) {
mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3;
exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3;
}
lp55xx_write(chip, LP8501_REG_OP_MODE, mode);
lp8501_wait_opmode_done();
lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec);
}
static int lp8501_update_program_memory(struct lp55xx_chip *chip,
const u8 *data, size_t size)
{
u8 pattern[LP8501_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 < LP8501_PROGRAM_LENGTH; i++)
lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0);
i = 0;
while ((offset < size - 1) && (i < LP8501_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, LP8501_REG_PROG_MEM + i, pattern[i]);
return 0;
err:
dev_err(&chip->cl->dev, "wrong pattern format\n");
return -EINVAL;
}
static void lp8501_firmware_loaded(struct lp55xx_chip *chip)
{
const struct firmware *fw = chip->fw;
if (fw->size > LP8501_PROGRAM_LENGTH) {
dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
fw->size);
return;
}
/*
* Program memory sequence
* 1) set engine mode to "LOAD"
* 2) write firmware data into program memory
*/
lp8501_load_engine(chip);
lp8501_update_program_memory(chip, fw->data, fw->size);
}
static int lp8501_led_brightness(struct lp55xx_led *led)
{
struct lp55xx_chip *chip = led->chip;
int ret;
mutex_lock(&chip->lock);
ret = lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + led->chan_nr,
led->brightness);
mutex_unlock(&chip->lock);
return ret;
}
/* Chip specific configurations */
static struct lp55xx_device_config lp8501_cfg = {
.reset = {
.addr = LP8501_REG_RESET,
.val = LP8501_RESET,
},
.enable = {
.addr = LP8501_REG_ENABLE,
.val = LP8501_ENABLE,
},
.max_channel = LP8501_MAX_LEDS,
.post_init_device = lp8501_post_init_device,
.brightness_fn = lp8501_led_brightness,
.set_led_current = lp8501_set_led_current,
.firmware_cb = lp8501_firmware_loaded,
.run_engine = lp8501_run_engine,
};
static int lp8501_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 = dev_get_platdata(&client->dev);
struct device_node *np = dev_of_node(&client->dev);
chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->cfg = &lp8501_cfg;
if (!pdata) {
if (np) {
pdata = lp55xx_of_populate_pdata(&client->dev, np,
chip);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
} else {
dev_err(&client->dev, "no platform data\n");
return -EINVAL;
}
}
led = devm_kcalloc(&client->dev,
pdata->num_channels, sizeof(*led), GFP_KERNEL);
if (!led)
return -ENOMEM;
chip->cl = client;
chip->pdata = pdata;
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_out;
ret = lp55xx_register_sysfs(chip);
if (ret) {
dev_err(&client->dev, "registering sysfs failed\n");
goto err_out;
}
return 0;
err_out:
lp55xx_deinit_device(chip);
err_init:
return ret;
}
static void lp8501_remove(struct i2c_client *client)
{
struct lp55xx_led *led = i2c_get_clientdata(client);
struct lp55xx_chip *chip = led->chip;
lp8501_stop_engine(chip);
lp55xx_unregister_sysfs(chip);
lp55xx_deinit_device(chip);
}
static const struct i2c_device_id lp8501_id[] = {
{ "lp8501", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lp8501_id);
#ifdef CONFIG_OF
static const struct of_device_id of_lp8501_leds_match[] = {
{ .compatible = "ti,lp8501", },
{},
};
MODULE_DEVICE_TABLE(of, of_lp8501_leds_match);
#endif
static struct i2c_driver lp8501_driver = {
.driver = {
.name = "lp8501",
.of_match_table = of_match_ptr(of_lp8501_leds_match),
},
.probe = lp8501_probe,
.remove = lp8501_remove,
.id_table = lp8501_id,
};
module_i2c_driver(lp8501_driver);
MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");