Re: [PATCH v9 07/15] leds: lp50xx: Add the LP50XX family of the RGB LED driver

[Dan Murphy]

Jacek

On 9/25/19 4:27 PM, Jacek Anaszewski wrote:
> Dan,
>
> On 9/25/19 7:46 PM, Dan Murphy wrote:

<big_snip>

> > +
> > +static int lp50xx_brightness_set(struct led_classdev *cdev,
> > +			     enum led_brightness brightness)
> > +{
> > +	struct lp50xx_led *led = container_of(cdev, struct lp50xx_led, led_dev);
> > +	const struct lp50xx_chip_info *led_chip = led->priv->chip_info;
> > +	struct led_mc_color_entry *color_data;
> > +	u8 led_offset, reg_val, reg_color_offset;
> > +	int ret = 0;
> > +
> > +	mutex_lock(&led->priv->lock);
> > +
> > +	if (led->ctrl_bank_enabled)
> > +		reg_val = led_chip->bank_brt_reg;
> > +	else
> > +		reg_val = led_chip->led_brightness0_reg +
> > +			  led->led_number;
> > +
> > +	ret = regmap_write(led->priv->regmap, reg_val, brightness);
> > +	if (ret) {
> > +		dev_err(&led->priv->client->dev,
> > +			"Cannot write brightness value %d\n", ret);
> > +		goto out;
> > +	}
> > +
> > +	list_for_each_entry(color_data, &led->mc_cdev.color_list, list) {
> > +		if (color_data->led_color_id == LED_COLOR_ID_RED)
> > +			reg_color_offset = 0;
> > +		else if (color_data->led_color_id == LED_COLOR_ID_GREEN)
> > +			reg_color_offset = 1;
> > +		else if (color_data->led_color_id == LED_COLOR_ID_BLUE)
> > +			reg_color_offset = 2;
> > +		else
> > +			continue;
> This else case is quite erroneous. Sheer continue is just ignoring
> serious problem. I'd log the problem and return -EINVAL.
Ack.
> Also, you could have a macro for mapping color_id to offset.
If the code needed to do this more then once I could justify a macro. 
But this is the only instance of this check.
> > +
> > +		if (led->ctrl_bank_enabled) {
> > +			reg_val = led_chip->bank_mix_reg + reg_color_offset;
> > +		} else {
> > +			led_offset = (led->led_number * 3)  + reg_color_offset;
> > +			reg_val = led_chip->mix_out0_reg + led_offset;
> > +		}
> > +
> > +		ret = regmap_write(led->priv->regmap, reg_val,
> > +				   color_data->intensity);
> > +		if (ret) {
> > +			dev_err(&led->priv->client->dev,
> > +				"Cannot write intensity value %d\n", ret);
> > +			goto out;
> > +		}
> > +	}
> > +out:
> > +	mutex_unlock(&led->priv->lock);
> > +	return ret;
> > +}
> > +
> > +static enum led_brightness lp50xx_brightness_get(struct led_classdev *cdev)
> > +{
> > +	struct lp50xx_led *led = container_of(cdev, struct lp50xx_led, led_dev);
> > +	const struct lp50xx_chip_info *led_chip = led->priv->chip_info;
> > +	unsigned int brt_val;
> > +	u8 reg_val;
> > +	int ret;
> > +
> > +	mutex_lock(&led->priv->lock);
> > +
> > +	if (led->ctrl_bank_enabled)
> > +		reg_val = led_chip->bank_brt_reg;
> > +	else
> > +		reg_val = led_chip->led_brightness0_reg + led->led_number;
> > +
> > +	ret = regmap_read(led->priv->regmap, reg_val, &brt_val);
> > +
> > +	mutex_unlock(&led->priv->lock);
> > +
> > +	return brt_val;
> > +}
> > +
> > +static int lp50xx_set_banks(struct lp50xx *priv, u32 led_banks[])
> > +{
> > +	u8 led_config_lo, led_config_hi;
> > +	u32 bank_enable_mask = 0;
> > +	int ret;
> > +	int i;
> > +
> > +	for (i = 0; i < priv->chip_info->num_leds; i++)
> > +		bank_enable_mask |= (1 << led_banks[i]);
> > +
> > +	led_config_lo = (u8)(bank_enable_mask & 0xff);
> > +	led_config_hi = (u8)(bank_enable_mask >> 8) & 0xff;
> > +
> > +	ret = regmap_write(priv->regmap, LP50XX_LED_CFG0, led_config_lo);
> > +	if (ret)
> > +		return ret;
> > +
> > +	if (led_config_hi)
> Now I think that less questionable would be writing led_config_hi always
> for devices that have CFG1 register. IOW write led_config_hi also
> when it equals 0.

Ack. I will have to modify the check to only write this for LP5030/36 
as those are the only 2 that have the CFG1 register.

> > +		ret = regmap_write(priv->regmap, LP5036_LED_CFG1,
> > +				   led_config_hi);
> > +
> > +	return ret;
> > +}
> > +
> > +static int lp50xx_reset(struct lp50xx *priv)
> > +{
> > +	if (priv->enable_gpio)
> > +		return gpiod_direction_output(priv->enable_gpio, 1);
> > +	else
> > +		return regmap_write(priv->regmap, priv->chip_info->reset_reg,
> > +				    LP50XX_SW_RESET);
> > +}
> > +
> > +static int lp50xx_enable_disable(struct lp50xx *priv, u8 enable_disable)
> > +{
> > +	return regmap_write(priv->regmap, LP50XX_DEV_CFG0, enable_disable);
> > +}
> > +
> > +static int lp50xx_probe_dt(struct lp50xx *priv)
> > +{
> > +	u32 led_banks[LP5036_MAX_LED_MODULES];
> > +	struct fwnode_handle *child = NULL;
> > +	struct fwnode_handle *led_node = NULL;
> > +	struct led_init_data init_data;
> > +	struct lp50xx_led *led;
> > +	int num_colors;
> > +	u32 color_id;
> > +	int led_number;
> > +	size_t i = 0;
> > +	int ret;
> > +
> > +	priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
> > +						   "enable", GPIOD_OUT_LOW);
> > +	if (IS_ERR(priv->enable_gpio)) {
> > +		ret = PTR_ERR(priv->enable_gpio);
> > +		dev_err(&priv->client->dev, "Failed to get enable gpio: %d\n",
> > +			ret);
> > +		return ret;
> > +	}
> > +
> > +	priv->regulator = devm_regulator_get(&priv->client->dev, "vled");
> > +	if (IS_ERR(priv->regulator))
> > +		priv->regulator = NULL;
> > +
> > +	device_for_each_child_node(&priv->client->dev, child) {
> > +		led = &priv->leds[i];
> > +		if (fwnode_property_present(child, "ti,led-bank")) {
> > +			ret = fwnode_property_read_u32_array(child,
> > +							     "ti,led-bank",
> > +							     NULL, 0);
> > +			ret = fwnode_property_read_u32_array(child,
> > +							     "ti,led-bank",
> > +							     led_banks,
> > +							     ret);
> > +
> > +			priv->num_of_banked_leds = ARRAY_SIZE(led_banks);
> > +
> > +			ret = lp50xx_set_banks(priv, led_banks);
> > +			if (ret) {
> > +				dev_err(&priv->client->dev,
> > +					"Cannot setup banked LEDs\n");
> > +				fwnode_handle_put(child);
> > +				goto child_out;
> > +			}
> > +			led->ctrl_bank_enabled = 1;
> > +
> > +		} else {
> > +			ret = fwnode_property_read_u32(child, "reg",
> > +					       &led_number);
> Not checking ret val?
Yes it is after the else case. But I should probably check return for 
the led-bank
> > +
> > +			led->led_number = led_number;
> > +		}
> > +		if (ret) {
> > +			dev_err(&priv->client->dev,
> > +				"led sourcing property missing\n");
> > +			fwnode_handle_put(child);
> > +			goto child_out;
> > +		}
> > +

Dan

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