[ CCing Gary Stein ]
On Mon, 11 Mar 2019, Chris Boyle wrote:
> The Logitech G940 has 8 illuminated buttons on the base of the throttle.
> Make these available as LED class devices.
>
> Each button has two LEDs (green and red). Turning both on gives amber, and
> userland can do that if amber is wanted (so no need to abstract it here).
>
> Signed-off-by: Chris Boyle <chris@xxxxxxxxxx>
> ---
> drivers/hid/hid-lg.c | 100 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 100 insertions(+)
>
> diff --git a/drivers/hid/hid-lg.c b/drivers/hid/hid-lg.c
> index d822cd98d677..968140c1f78d 100644
> --- a/drivers/hid/hid-lg.c
> +++ b/drivers/hid/hid-lg.c
> @@ -870,6 +870,60 @@ static int lg_raw_event(struct hid_device *hdev, struct hid_report *report,
> return 0;
> }
>
> +#define g940_validate_leds() hid_validate_values(hdev, HID_FEATURE_REPORT, \
> + 3, 0, 15)
> +
> +struct g940_led {
> + struct led_classdev cdev;
> + unsigned int index;
> +};
> +
> +static int lg_g940_led_set(struct led_classdev *cdev, enum led_brightness value)
> +{
> + struct g940_led *led = container_of(cdev, struct g940_led, cdev);
> + struct device *dev = cdev->dev->parent;
> + struct hid_device *hdev = to_hid_device(dev);
> + struct hid_report *report;
> +
> + if (cdev->flags & LED_UNREGISTERING) {
> + /* hdev is invalid and the device will turn off LEDs anyway */
> + return -ENODEV;
> + }
> +
> + report = g940_validate_leds();
> +
> + if (!report) {
> + hid_err(hdev, "LED feature report invalid");
> + return -ENODEV;
> + }
> + report->field[0]->value[led->index] = value ? 1 : 0;
> + hid_hw_request(hdev, report, HID_REQ_SET_REPORT);
> + return 0;
> +}
> +
> +static enum led_brightness lg_g940_led_get(struct led_classdev *cdev)
> +{
> + struct g940_led *led = container_of(cdev, struct g940_led, cdev);
> + struct device *dev = cdev->dev->parent;
> + struct hid_device *hdev = to_hid_device(dev);
> + struct hid_report *report;
> +
> + if (cdev->flags & LED_UNREGISTERING) {
> + /* hdev is invalid and the device will turn off LEDs anyway */
> + return LED_OFF;
> + }
> +
> + report = g940_validate_leds();
> +
> + if (!report) {
> + hid_err(hdev, "LED feature report invalid");
> + return LED_OFF;
> + }
> + hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
> + hid_hw_wait(hdev);
> + return report->field[0]->value[led->index] ? LED_ON : LED_OFF;
> +}
> +
> static int lg_probe(struct hid_device *hdev, const struct hid_device_id *id)
> {
> struct usb_interface *iface = to_usb_interface(hdev->dev.parent);
> @@ -943,6 +997,52 @@ static int lg_probe(struct hid_device *hdev, const struct hid_device_id *id)
> kfree(buf);
> }
>
> + if (hdev->product == USB_DEVICE_ID_LOGITECH_FLIGHT_SYSTEM_G940) {
> + struct hid_report *report;
> + struct g940_led *leds;
> + unsigned int i;
> +
> + report = g940_validate_leds();
> + if (!report) {
> + ret = -ENODEV;
> + goto err_free;
> + }
> + leds = devm_kcalloc(&hdev->dev, 16, sizeof(struct g940_led),
> + GFP_KERNEL);
> + if (!leds) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
> + /* P1-8 red followed by P1-8 green (set both on for amber) */
> + for (i = 0; i < 16; i++) {
> + leds[i].index = i;
> + leds[i].cdev.name =
> + devm_kasprintf(&hdev->dev, GFP_KERNEL,
> + "g940:%s:P%u",
> + i > 7 ? "green" : "red",
> + (i % 8) + 1);
> + if (!leds[i].cdev.name) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
> + leds[i].cdev.max_brightness = LED_ON;
> + leds[i].cdev.flags = LED_HW_PLUGGABLE;
> + leds[i].cdev.brightness_get = lg_g940_led_get;
> + leds[i].cdev.brightness_set_blocking = lg_g940_led_set;
> + devm_led_classdev_register(&hdev->dev, &leds[i].cdev);
> + /* switch greens on */
> + report->field[0]->value[i] = i > 7 ? 1 : 0;
> + }
> +
> + /* With no LED I/O, the device would do a pretty startup
> + * animation from all red to all green when plugged in.
> + * Unfortunately the initial reads during led_classdev_register
> + * freeze the animation at all red. We could defer such reads,
> + * but it's a lot simpler to just set all green now.
> + */
> + hid_hw_request(hdev, report, HID_REQ_SET_REPORT);
> + }
> +
> if (drv_data->quirks & LG_FF)
> ret = lgff_init(hdev);
> else if (drv_data->quirks & LG_FF2)
> --
> 2.17.1
>
>
> --
> Chris Boyle
> https://chris.boyle.name/
>
--
Jiri Kosina
SUSE Labs
