Re: [PATCH v2 09/13] HID: playstation: add DualSense lightbar support

["Barnabás Pőcze" <pobrn@protonmail.com>]

2021. január 2., szombat 23:31 keltezéssel, Roderick Colenbrander írta:

> From: Roderick Colenbrander <roderick.colenbrander@sony.com>
>
> Expose the DualSense its RGB lightbar using the new multicolor LED
> framework.
>
> Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
> [...]
> +/* Register a DualSense/DualShock4 RGB lightbar represented by a multicolor LED. */
> +static int ps_lightbar_register(struct ps_device *ps_dev, struct led_classdev_mc *lightbar_mc_dev,
> +	int (*brightness_set)(struct led_classdev *, enum led_brightness))
> +{
> +	struct hid_device *hdev = ps_dev->hdev;
> +	struct mc_subled *mc_led_info;
> +	struct led_classdev *led_cdev;
> +	int ret;
> +
> +	mc_led_info = devm_kzalloc(&hdev->dev, 3*sizeof(*mc_led_info), GFP_KERNEL);

I believe `devm_kmalloc_array()` would be more appropriate. Have you looked at it?


> +	if (!mc_led_info)
> +		return -ENOMEM;
> +
> +	mc_led_info[0].color_index = LED_COLOR_ID_RED;
> +	mc_led_info[0].channel = 0;
> +	mc_led_info[1].color_index = LED_COLOR_ID_GREEN;
> +	mc_led_info[1].channel = 1;
> +	mc_led_info[2].color_index = LED_COLOR_ID_BLUE;
> +	mc_led_info[2].channel = 2;

Just a small note, as far as I'm aware, the `channel` member is not used by
multicolor LED functions, and it's not even used in this module as far as I see.


> +
> +	lightbar_mc_dev->subled_info = mc_led_info;
> +	lightbar_mc_dev->num_colors = 3;
> +
> +	led_cdev = &lightbar_mc_dev->led_cdev;
> +	led_cdev->name = devm_kasprintf(&hdev->dev, GFP_KERNEL, "playstation::%pMR::rgb",
> +			ps_dev->mac_address);
> +	led_cdev->brightness = 255;
> +	led_cdev->max_brightness = 255;
> +	led_cdev->brightness_set_blocking = brightness_set;
> +
> +	ret = devm_led_classdev_multicolor_register(&hdev->dev, lightbar_mc_dev);
> +	if (ret < 0) {
> +		hid_err(hdev, "Cannot register multicolor LED device\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static struct input_dev *ps_sensors_create(struct hid_device *hdev, int accel_range, int accel_res,
>  		int gyro_range, int gyro_res)
>  {
> @@ -601,6 +652,27 @@  static int dualsense_get_mac_address(struct dualsense *ds)
>  	return ret;
>  }
>
> +static int dualsense_lightbar_set_brightness(struct led_classdev *cdev,
> +	enum led_brightness brightness)
> +{
> +	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
> +	struct hid_device *hdev = to_hid_device(cdev->dev->parent);
> +	struct dualsense *ds = hid_get_drvdata(hdev);

I think the previous two lines could be replaced with

```
struct dualsense *ds = container_of(mc_cdev, struct dualsense, lightbar);
```


> +	unsigned long flags;
> +
> +	led_mc_calc_color_components(mc_cdev, brightness);
> +
> +	spin_lock_irqsave(&ds->base.lock, flags);
> +	ds->update_lightbar = true;
> +	ds->lightbar_red = mc_cdev->subled_info[0].brightness;
> +	ds->lightbar_green = mc_cdev->subled_info[1].brightness;
> +	ds->lightbar_blue = mc_cdev->subled_info[2].brightness;
> +	spin_unlock_irqrestore(&ds->base.lock, flags);
> +
> +	schedule_work(&ds->output_worker);
> +	return 0;
> +}
> +
>  static void dualsense_init_output_report(struct dualsense *ds, struct dualsense_output_report *rp,
>  		void *buf)
>  {
> @@ -682,6 +754,15 @@  static void dualsense_output_worker(struct work_struct *work)
>  		ds->update_rumble = false;
>  	}
>
> +	if (ds->update_lightbar) {
> +		common->valid_flag1 |= DS_OUTPUT_VALID_FLAG1_LIGHTBAR_CONTROL_ENABLE;
> +		common->lightbar_red = ds->lightbar_red;
> +		common->lightbar_green = ds->lightbar_green;
> +		common->lightbar_blue = ds->lightbar_blue;
> +
> +		ds->update_lightbar = false;
> +	}
> +
>  	spin_unlock_irqrestore(&ds->base.lock, flags);
>
>  	dualsense_send_output_report(ds, &report);
> @@ -861,6 +942,30 @@  static int dualsense_play_effect(struct input_dev *dev, void *data, struct ff_ef
>  	return 0;
>  }
> [...]
>  static struct ps_device *dualsense_create(struct hid_device *hdev)
>  {
>  	struct dualsense *ds;
> @@ -930,6 +1035,18 @@  static struct ps_device *dualsense_create(struct hid_device *hdev)
>  	if (ret < 0)
>  		goto err;
>
> +	/* The hardware may have control over the LEDs (e.g. in Bluetooth on startup).
> +	 * Reset the LEDs (lightbar, mute, player leds), so we can control them
> +	 * from software.
> +	 */
> +	ret = dualsense_reset_leds(ds);
> +	if (ret < 0)

I believe if `dualsense_reset_leds()` can only return 0 on success, or an errno,
then `if (ret)` would be better.


> +		goto err;
> +
> +	ret = ps_lightbar_register(ps_dev, &ds->lightbar, dualsense_lightbar_set_brightness);
> +	if (ret < 0)
> [...]

Same here.


Regards,
Barnabás Pőcze