linux/drivers/leds/leds-tlc591xx.c
Yang Yingliang ee522bcf02 leds: tlc591xx: fix return value check in tlc591xx_probe()
After device_get_match_data(), tlc591xx is not checked, add
check for it and also check np after dev_of_node.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-05-10 11:58:54 +02:00

243 lines
5.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2014 Belkin Inc.
* Copyright 2015 Andrew Lunn <andrew@lunn.ch>
*/
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#define TLC591XX_MAX_LEDS 16
#define TLC591XX_MAX_BRIGHTNESS 256
#define TLC591XX_REG_MODE1 0x00
#define MODE1_RESPON_ADDR_MASK 0xF0
#define MODE1_NORMAL_MODE (0 << 4)
#define MODE1_SPEED_MODE (1 << 4)
#define TLC591XX_REG_MODE2 0x01
#define MODE2_DIM (0 << 5)
#define MODE2_BLINK (1 << 5)
#define MODE2_OCH_STOP (0 << 3)
#define MODE2_OCH_ACK (1 << 3)
#define TLC591XX_REG_PWM(x) (0x02 + (x))
#define TLC591XX_REG_GRPPWM 0x12
#define TLC591XX_REG_GRPFREQ 0x13
/* LED Driver Output State, determine the source that drives LED outputs */
#define LEDOUT_OFF 0x0 /* Output LOW */
#define LEDOUT_ON 0x1 /* Output HI-Z */
#define LEDOUT_DIM 0x2 /* Dimming */
#define LEDOUT_BLINK 0x3 /* Blinking */
#define LEDOUT_MASK 0x3
#define ldev_to_led(c) container_of(c, struct tlc591xx_led, ldev)
struct tlc591xx_led {
bool active;
unsigned int led_no;
struct led_classdev ldev;
struct tlc591xx_priv *priv;
};
struct tlc591xx_priv {
struct tlc591xx_led leds[TLC591XX_MAX_LEDS];
struct regmap *regmap;
unsigned int reg_ledout_offset;
};
struct tlc591xx {
unsigned int max_leds;
unsigned int reg_ledout_offset;
};
static const struct tlc591xx tlc59116 = {
.max_leds = 16,
.reg_ledout_offset = 0x14,
};
static const struct tlc591xx tlc59108 = {
.max_leds = 8,
.reg_ledout_offset = 0x0c,
};
static int
tlc591xx_set_mode(struct regmap *regmap, u8 mode)
{
int err;
u8 val;
err = regmap_write(regmap, TLC591XX_REG_MODE1, MODE1_NORMAL_MODE);
if (err)
return err;
val = MODE2_OCH_STOP | mode;
return regmap_write(regmap, TLC591XX_REG_MODE2, val);
}
static int
tlc591xx_set_ledout(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
u8 val)
{
unsigned int i = (led->led_no % 4) * 2;
unsigned int mask = LEDOUT_MASK << i;
unsigned int addr = priv->reg_ledout_offset + (led->led_no >> 2);
val = val << i;
return regmap_update_bits(priv->regmap, addr, mask, val);
}
static int
tlc591xx_set_pwm(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
u8 brightness)
{
u8 pwm = TLC591XX_REG_PWM(led->led_no);
return regmap_write(priv->regmap, pwm, brightness);
}
static int
tlc591xx_brightness_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct tlc591xx_led *led = ldev_to_led(led_cdev);
struct tlc591xx_priv *priv = led->priv;
int err;
switch ((int)brightness) {
case 0:
err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF);
break;
case TLC591XX_MAX_BRIGHTNESS:
err = tlc591xx_set_ledout(priv, led, LEDOUT_ON);
break;
default:
err = tlc591xx_set_ledout(priv, led, LEDOUT_DIM);
if (!err)
err = tlc591xx_set_pwm(priv, led, brightness);
}
return err;
}
static const struct regmap_config tlc591xx_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0x1e,
};
static const struct of_device_id of_tlc591xx_leds_match[] = {
{ .compatible = "ti,tlc59116",
.data = &tlc59116 },
{ .compatible = "ti,tlc59108",
.data = &tlc59108 },
{},
};
MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match);
static int
tlc591xx_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device_node *np, *child;
struct device *dev = &client->dev;
const struct tlc591xx *tlc591xx;
struct tlc591xx_priv *priv;
int err, count, reg;
np = dev_of_node(dev);
if (!np)
return -ENODEV;
tlc591xx = device_get_match_data(dev);
if (!tlc591xx)
return -ENODEV;
count = of_get_available_child_count(np);
if (!count || count > tlc591xx->max_leds)
return -EINVAL;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap);
if (IS_ERR(priv->regmap)) {
err = PTR_ERR(priv->regmap);
dev_err(dev, "Failed to allocate register map: %d\n", err);
return err;
}
priv->reg_ledout_offset = tlc591xx->reg_ledout_offset;
i2c_set_clientdata(client, priv);
err = tlc591xx_set_mode(priv->regmap, MODE2_DIM);
if (err < 0)
return err;
for_each_available_child_of_node(np, child) {
struct tlc591xx_led *led;
struct led_init_data init_data = {};
init_data.fwnode = of_fwnode_handle(child);
err = of_property_read_u32(child, "reg", &reg);
if (err) {
of_node_put(child);
return err;
}
if (reg < 0 || reg >= tlc591xx->max_leds ||
priv->leds[reg].active) {
of_node_put(child);
return -EINVAL;
}
led = &priv->leds[reg];
led->active = true;
led->priv = priv;
led->led_no = reg;
led->ldev.brightness_set_blocking = tlc591xx_brightness_set;
led->ldev.max_brightness = TLC591XX_MAX_BRIGHTNESS;
err = devm_led_classdev_register_ext(dev, &led->ldev,
&init_data);
if (err < 0) {
of_node_put(child);
return dev_err_probe(dev, err,
"couldn't register LED %s\n",
led->ldev.name);
}
}
return 0;
}
static const struct i2c_device_id tlc591xx_id[] = {
{ "tlc59116" },
{ "tlc59108" },
{},
};
MODULE_DEVICE_TABLE(i2c, tlc591xx_id);
static struct i2c_driver tlc591xx_driver = {
.driver = {
.name = "tlc591xx",
.of_match_table = of_match_ptr(of_tlc591xx_leds_match),
},
.probe = tlc591xx_probe,
.id_table = tlc591xx_id,
};
module_i2c_driver(tlc591xx_driver);
MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TLC591XX LED driver");