linux/drivers/leds/leds-lp55xx-common.c
Merlijn Wajer 9e87a8da74 leds: lp55xx: initialise output direction from dts
Commit a5d3d1adc9 ("leds: lp55xx: Initialize enable GPIO direction to
output") attempts to fix this, but the fix did not work since at least
for the Nokia N900 the value needs to be set to HIGH, per the device
tree. So rather than hardcoding the value to a potentially invalid value
for some devices, let's set direction in lp55xx_init_device.

Fixes: a5d3d1adc9 ("leds: lp55xx: Initialize enable GPIO direction to output")
Fixes: 92a81562e6 ("leds: lp55xx: Add multicolor framework support to lp55xx")
Fixes: ac219bf3c9 ("leds: lp55xx: Convert to use GPIO descriptors")
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2022-01-12 19:43:15 +01:00

713 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* LP5521/LP5523/LP55231/LP5562 Common Driver
*
* Copyright 2012 Texas Instruments
*
* Author: Milo(Woogyom) Kim <milo.kim@ti.com>
*
* Derived from leds-lp5521.c, leds-lp5523.c
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
#include "leds-lp55xx-common.h"
/* External clock rate */
#define LP55XX_CLK_32K 32768
static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
{
return container_of(cdev, struct lp55xx_led, cdev);
}
static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
{
return cdev_to_lp55xx_led(dev_get_drvdata(dev));
}
static struct lp55xx_led *mcled_cdev_to_led(struct led_classdev_mc *mc_cdev)
{
return container_of(mc_cdev, struct lp55xx_led, mc_cdev);
}
static void lp55xx_reset_device(struct lp55xx_chip *chip)
{
struct lp55xx_device_config *cfg = chip->cfg;
u8 addr = cfg->reset.addr;
u8 val = cfg->reset.val;
/* no error checking here because no ACK from the device after reset */
lp55xx_write(chip, addr, val);
}
static int lp55xx_detect_device(struct lp55xx_chip *chip)
{
struct lp55xx_device_config *cfg = chip->cfg;
u8 addr = cfg->enable.addr;
u8 val = cfg->enable.val;
int ret;
ret = lp55xx_write(chip, addr, val);
if (ret)
return ret;
usleep_range(1000, 2000);
ret = lp55xx_read(chip, addr, &val);
if (ret)
return ret;
if (val != cfg->enable.val)
return -ENODEV;
return 0;
}
static int lp55xx_post_init_device(struct lp55xx_chip *chip)
{
struct lp55xx_device_config *cfg = chip->cfg;
if (!cfg->post_init_device)
return 0;
return cfg->post_init_device(chip);
}
static ssize_t led_current_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct lp55xx_led *led = dev_to_lp55xx_led(dev);
return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);
}
static ssize_t led_current_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct lp55xx_led *led = dev_to_lp55xx_led(dev);
struct lp55xx_chip *chip = led->chip;
unsigned long curr;
if (kstrtoul(buf, 0, &curr))
return -EINVAL;
if (curr > led->max_current)
return -EINVAL;
if (!chip->cfg->set_led_current)
return len;
mutex_lock(&chip->lock);
chip->cfg->set_led_current(led, (u8)curr);
mutex_unlock(&chip->lock);
return len;
}
static ssize_t max_current_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct lp55xx_led *led = dev_to_lp55xx_led(dev);
return scnprintf(buf, PAGE_SIZE, "%d\n", led->max_current);
}
static DEVICE_ATTR_RW(led_current);
static DEVICE_ATTR_RO(max_current);
static struct attribute *lp55xx_led_attrs[] = {
&dev_attr_led_current.attr,
&dev_attr_max_current.attr,
NULL,
};
ATTRIBUTE_GROUPS(lp55xx_led);
static int lp55xx_set_mc_brightness(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct led_classdev_mc *mc_dev = lcdev_to_mccdev(cdev);
struct lp55xx_led *led = mcled_cdev_to_led(mc_dev);
struct lp55xx_device_config *cfg = led->chip->cfg;
led_mc_calc_color_components(&led->mc_cdev, brightness);
return cfg->multicolor_brightness_fn(led);
}
static int lp55xx_set_brightness(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
struct lp55xx_device_config *cfg = led->chip->cfg;
led->brightness = (u8)brightness;
return cfg->brightness_fn(led);
}
static int lp55xx_init_led(struct lp55xx_led *led,
struct lp55xx_chip *chip, int chan)
{
struct lp55xx_platform_data *pdata = chip->pdata;
struct lp55xx_device_config *cfg = chip->cfg;
struct device *dev = &chip->cl->dev;
int max_channel = cfg->max_channel;
struct mc_subled *mc_led_info;
struct led_classdev *led_cdev;
char name[32];
int i, j = 0;
int ret;
if (chan >= max_channel) {
dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
return -EINVAL;
}
if (pdata->led_config[chan].led_current == 0)
return 0;
if (pdata->led_config[chan].name) {
led->cdev.name = pdata->led_config[chan].name;
} else {
snprintf(name, sizeof(name), "%s:channel%d",
pdata->label ? : chip->cl->name, chan);
led->cdev.name = name;
}
if (pdata->led_config[chan].num_colors > 1) {
mc_led_info = devm_kcalloc(dev,
pdata->led_config[chan].num_colors,
sizeof(*mc_led_info), GFP_KERNEL);
if (!mc_led_info)
return -ENOMEM;
led_cdev = &led->mc_cdev.led_cdev;
led_cdev->name = led->cdev.name;
led_cdev->brightness_set_blocking = lp55xx_set_mc_brightness;
led->mc_cdev.num_colors = pdata->led_config[chan].num_colors;
for (i = 0; i < led->mc_cdev.num_colors; i++) {
mc_led_info[i].color_index =
pdata->led_config[chan].color_id[i];
mc_led_info[i].channel =
pdata->led_config[chan].output_num[i];
j++;
}
led->mc_cdev.subled_info = mc_led_info;
} else {
led->cdev.brightness_set_blocking = lp55xx_set_brightness;
}
led->cdev.groups = lp55xx_led_groups;
led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
led->led_current = pdata->led_config[chan].led_current;
led->max_current = pdata->led_config[chan].max_current;
led->chan_nr = pdata->led_config[chan].chan_nr;
if (led->chan_nr >= max_channel) {
dev_err(dev, "Use channel numbers between 0 and %d\n",
max_channel - 1);
return -EINVAL;
}
if (pdata->led_config[chan].num_colors > 1)
ret = devm_led_classdev_multicolor_register(dev, &led->mc_cdev);
else
ret = devm_led_classdev_register(dev, &led->cdev);
if (ret) {
dev_err(dev, "led register err: %d\n", ret);
return ret;
}
return 0;
}
static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
{
struct lp55xx_chip *chip = context;
struct device *dev = &chip->cl->dev;
enum lp55xx_engine_index idx = chip->engine_idx;
if (!fw) {
dev_err(dev, "firmware request failed\n");
return;
}
/* handling firmware data is chip dependent */
mutex_lock(&chip->lock);
chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
chip->fw = fw;
if (chip->cfg->firmware_cb)
chip->cfg->firmware_cb(chip);
mutex_unlock(&chip->lock);
/* firmware should be released for other channel use */
release_firmware(chip->fw);
chip->fw = NULL;
}
static int lp55xx_request_firmware(struct lp55xx_chip *chip)
{
const char *name = chip->cl->name;
struct device *dev = &chip->cl->dev;
return request_firmware_nowait(THIS_MODULE, false, name, dev,
GFP_KERNEL, chip, lp55xx_firmware_loaded);
}
static ssize_t select_engine_show(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;
return sprintf(buf, "%d\n", chip->engine_idx);
}
static ssize_t select_engine_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
unsigned long val;
int ret;
if (kstrtoul(buf, 0, &val))
return -EINVAL;
/* select the engine to be run */
switch (val) {
case LP55XX_ENGINE_1:
case LP55XX_ENGINE_2:
case LP55XX_ENGINE_3:
mutex_lock(&chip->lock);
chip->engine_idx = val;
ret = lp55xx_request_firmware(chip);
mutex_unlock(&chip->lock);
break;
default:
dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
return -EINVAL;
}
if (ret) {
dev_err(dev, "request firmware err: %d\n", ret);
return ret;
}
return len;
}
static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
{
if (chip->cfg->run_engine)
chip->cfg->run_engine(chip, start);
}
static ssize_t run_engine_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
struct lp55xx_chip *chip = led->chip;
unsigned long val;
if (kstrtoul(buf, 0, &val))
return -EINVAL;
/* run or stop the selected engine */
if (val <= 0) {
lp55xx_run_engine(chip, false);
return len;
}
mutex_lock(&chip->lock);
lp55xx_run_engine(chip, true);
mutex_unlock(&chip->lock);
return len;
}
static DEVICE_ATTR_RW(select_engine);
static DEVICE_ATTR_WO(run_engine);
static struct attribute *lp55xx_engine_attributes[] = {
&dev_attr_select_engine.attr,
&dev_attr_run_engine.attr,
NULL,
};
static const struct attribute_group lp55xx_engine_attr_group = {
.attrs = lp55xx_engine_attributes,
};
int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
{
return i2c_smbus_write_byte_data(chip->cl, reg, val);
}
EXPORT_SYMBOL_GPL(lp55xx_write);
int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
{
s32 ret;
ret = i2c_smbus_read_byte_data(chip->cl, reg);
if (ret < 0)
return ret;
*val = ret;
return 0;
}
EXPORT_SYMBOL_GPL(lp55xx_read);
int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
{
int ret;
u8 tmp;
ret = lp55xx_read(chip, reg, &tmp);
if (ret)
return ret;
tmp &= ~mask;
tmp |= val & mask;
return lp55xx_write(chip, reg, tmp);
}
EXPORT_SYMBOL_GPL(lp55xx_update_bits);
bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
{
struct clk *clk;
int err;
clk = devm_clk_get(&chip->cl->dev, "32k_clk");
if (IS_ERR(clk))
goto use_internal_clk;
err = clk_prepare_enable(clk);
if (err)
goto use_internal_clk;
if (clk_get_rate(clk) != LP55XX_CLK_32K) {
clk_disable_unprepare(clk);
goto use_internal_clk;
}
dev_info(&chip->cl->dev, "%dHz external clock used\n", LP55XX_CLK_32K);
chip->clk = clk;
return true;
use_internal_clk:
dev_info(&chip->cl->dev, "internal clock used\n");
return false;
}
EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
int lp55xx_init_device(struct lp55xx_chip *chip)
{
struct lp55xx_platform_data *pdata;
struct lp55xx_device_config *cfg;
struct device *dev = &chip->cl->dev;
int ret = 0;
WARN_ON(!chip);
pdata = chip->pdata;
cfg = chip->cfg;
if (!pdata || !cfg)
return -EINVAL;
if (pdata->enable_gpiod) {
gpiod_direction_output(pdata->enable_gpiod, 0);
gpiod_set_consumer_name(pdata->enable_gpiod, "LP55xx enable");
gpiod_set_value(pdata->enable_gpiod, 0);
usleep_range(1000, 2000); /* Keep enable down at least 1ms */
gpiod_set_value(pdata->enable_gpiod, 1);
usleep_range(1000, 2000); /* 500us abs min. */
}
lp55xx_reset_device(chip);
/*
* Exact value is not available. 10 - 20ms
* appears to be enough for reset.
*/
usleep_range(10000, 20000);
ret = lp55xx_detect_device(chip);
if (ret) {
dev_err(dev, "device detection err: %d\n", ret);
goto err;
}
/* chip specific initialization */
ret = lp55xx_post_init_device(chip);
if (ret) {
dev_err(dev, "post init device err: %d\n", ret);
goto err_post_init;
}
return 0;
err_post_init:
lp55xx_deinit_device(chip);
err:
return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_init_device);
void lp55xx_deinit_device(struct lp55xx_chip *chip)
{
struct lp55xx_platform_data *pdata = chip->pdata;
if (chip->clk)
clk_disable_unprepare(chip->clk);
if (pdata->enable_gpiod)
gpiod_set_value(pdata->enable_gpiod, 0);
}
EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
{
struct lp55xx_platform_data *pdata = chip->pdata;
struct lp55xx_device_config *cfg = chip->cfg;
int num_channels = pdata->num_channels;
struct lp55xx_led *each;
u8 led_current;
int ret;
int i;
if (!cfg->brightness_fn) {
dev_err(&chip->cl->dev, "empty brightness configuration\n");
return -EINVAL;
}
for (i = 0; i < num_channels; i++) {
/* do not initialize channels that are not connected */
if (pdata->led_config[i].led_current == 0)
continue;
led_current = pdata->led_config[i].led_current;
each = led + i;
ret = lp55xx_init_led(each, chip, i);
if (ret)
goto err_init_led;
chip->num_leds++;
each->chip = chip;
/* setting led current at each channel */
if (cfg->set_led_current)
cfg->set_led_current(each, led_current);
}
return 0;
err_init_led:
return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_register_leds);
int lp55xx_register_sysfs(struct lp55xx_chip *chip)
{
struct device *dev = &chip->cl->dev;
struct lp55xx_device_config *cfg = chip->cfg;
int ret;
if (!cfg->run_engine || !cfg->firmware_cb)
goto dev_specific_attrs;
ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
if (ret)
return ret;
dev_specific_attrs:
return cfg->dev_attr_group ?
sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
}
EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
{
struct device *dev = &chip->cl->dev;
struct lp55xx_device_config *cfg = chip->cfg;
if (cfg->dev_attr_group)
sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
}
EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
static int lp55xx_parse_common_child(struct device_node *np,
struct lp55xx_led_config *cfg,
int led_number, int *chan_nr)
{
int ret;
of_property_read_string(np, "chan-name",
&cfg[led_number].name);
of_property_read_u8(np, "led-cur",
&cfg[led_number].led_current);
of_property_read_u8(np, "max-cur",
&cfg[led_number].max_current);
ret = of_property_read_u32(np, "reg", chan_nr);
if (ret)
return ret;
if (*chan_nr < 0 || *chan_nr > cfg->max_channel)
return -EINVAL;
return 0;
}
static int lp55xx_parse_multi_led_child(struct device_node *child,
struct lp55xx_led_config *cfg,
int child_number, int color_number)
{
int chan_nr, color_id, ret;
ret = lp55xx_parse_common_child(child, cfg, child_number, &chan_nr);
if (ret)
return ret;
ret = of_property_read_u32(child, "color", &color_id);
if (ret)
return ret;
cfg[child_number].color_id[color_number] = color_id;
cfg[child_number].output_num[color_number] = chan_nr;
return 0;
}
static int lp55xx_parse_multi_led(struct device_node *np,
struct lp55xx_led_config *cfg,
int child_number)
{
struct device_node *child;
int num_colors = 0, ret;
for_each_available_child_of_node(np, child) {
ret = lp55xx_parse_multi_led_child(child, cfg, child_number,
num_colors);
if (ret) {
of_node_put(child);
return ret;
}
num_colors++;
}
cfg[child_number].num_colors = num_colors;
return 0;
}
static int lp55xx_parse_logical_led(struct device_node *np,
struct lp55xx_led_config *cfg,
int child_number)
{
int led_color, ret;
int chan_nr = 0;
cfg[child_number].default_trigger =
of_get_property(np, "linux,default-trigger", NULL);
ret = of_property_read_u32(np, "color", &led_color);
if (ret)
return ret;
if (led_color == LED_COLOR_ID_RGB)
return lp55xx_parse_multi_led(np, cfg, child_number);
ret = lp55xx_parse_common_child(np, cfg, child_number, &chan_nr);
if (ret < 0)
return ret;
cfg[child_number].chan_nr = chan_nr;
return ret;
}
struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
struct device_node *np,
struct lp55xx_chip *chip)
{
struct device_node *child;
struct lp55xx_platform_data *pdata;
struct lp55xx_led_config *cfg;
int num_channels;
int i = 0;
int ret;
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return ERR_PTR(-ENOMEM);
num_channels = of_get_available_child_count(np);
if (num_channels == 0) {
dev_err(dev, "no LED channels\n");
return ERR_PTR(-EINVAL);
}
cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return ERR_PTR(-ENOMEM);
pdata->led_config = &cfg[0];
pdata->num_channels = num_channels;
cfg->max_channel = chip->cfg->max_channel;
for_each_available_child_of_node(np, child) {
ret = lp55xx_parse_logical_led(child, cfg, i);
if (ret) {
of_node_put(child);
return ERR_PTR(-EINVAL);
}
i++;
}
of_property_read_string(np, "label", &pdata->label);
of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
pdata->enable_gpiod = devm_gpiod_get_optional(dev, "enable",
GPIOD_ASIS);
if (IS_ERR(pdata->enable_gpiod))
return ERR_CAST(pdata->enable_gpiod);
/* LP8501 specific */
of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
return pdata;
}
EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP55xx Common Driver");
MODULE_LICENSE("GPL");