[PATCH v3 4/7] drivers: leds: Add the iEi WT61P803 PUZZLE LED driver

Pavel Machek pavel at ucw.cz
Wed Sep 30 15:48:00 EDT 2020


Hi!

> +static int iei_wt61p803_puzzle_led_brightness_set_blocking(struct led_classdev *cdev,
> +		enum led_brightness brightness)
> +{
> +	struct iei_wt61p803_puzzle_led *priv = cdev_to_iei_wt61p803_puzzle_led(cdev);
> +	unsigned char *resp_buf = priv->response_buffer;
> +	unsigned char led_power_cmd[5] = {
> +		IEI_WT61P803_PUZZLE_CMD_HEADER_START,
> +		IEI_WT61P803_PUZZLE_CMD_LED,
> +		IEI_WT61P803_PUZZLE_CMD_LED_POWER,
> +		(char)IEI_LED_OFF
> +	};
> +	size_t reply_size;
> +
> +	mutex_lock(&priv->lock);
> +	if (brightness == LED_OFF) {
> +		led_power_cmd[3] = (char)IEI_LED_OFF;
> +		priv->led_power_state = LED_OFF;
> +	} else {
> +		led_power_cmd[3] = (char)IEI_LED_ON;
> +		priv->led_power_state = LED_ON;
> +	}
> +	mutex_unlock(&priv->lock);
> +
> +	return iei_wt61p803_puzzle_write_command(priv->mcu, led_power_cmd,
> +			sizeof(led_power_cmd), resp_buf, &reply_size);
> +}

Is the mutex needed? If so, should it include the
iei_wt61p803_puzzle_write_command()? Does
iei_wt61p803_puzzle_write_command() have internal locking to prevent
two messages from being mingled?

Best regards,
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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