HID: hid-lg4ff: Add support for G27 LEDs

This patch adds supports for controlling the LED 'tachometer' on
the G27 wheel, via the LED subsystem.

The 5 LEDs are arranged from right (1=grn, 2=grn, 3=yel, 4=yel, 5=red)
and 'mirrored' to the left (10 LEDs in total).

Signed-off-by: Simon Wood <simon@mungewell.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-lg4ff.c b/drivers/hid/hid-lg4ff.c
index 32c173fcb7f8e12b48efd0db4773d12709b9b5a5..1e942a0140384e9f2cca6145ce334a14883a1520 100644 (file)
--- a/drivers/hid/hid-lg4ff.c
+++ b/drivers/hid/hid-lg4ff.c
@@ -55,7 +55,10 @@ struct lg4ff_device_entry {
        __u16 range;
        __u16 min_range;
        __u16 max_range;
-       __u8  leds;
+#ifdef CONFIG_LEDS_CLASS
+       __u8  led_state;
+       struct led_classdev *led[5];
+#endif
        struct list_head list;
        void (*set_range)(struct hid_device *hid, u16 range);
 };
@@ -335,6 +338,88 @@ static ssize_t lg4ff_range_store(struct device *dev, struct device_attribute *at
        return count;
 }
 
+#ifdef CONFIG_LEDS_CLASS
+static void lg4ff_set_leds(struct hid_device *hid, __u8 leds)
+{
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+
+       report->field[0]->value[0] = 0xf8;
+       report->field[0]->value[1] = 0x12;
+       report->field[0]->value[2] = leds;
+       report->field[0]->value[3] = 0x00;
+       report->field[0]->value[4] = 0x00;
+       report->field[0]->value[5] = 0x00;
+       report->field[0]->value[6] = 0x00;
+       usbhid_submit_report(hid, report, USB_DIR_OUT);
+}
+
+static void lg4ff_led_set_brightness(struct led_classdev *led_cdev,
+                       enum led_brightness value)
+{
+       struct device *dev = led_cdev->dev->parent;
+       struct hid_device *hid = container_of(dev, struct hid_device, dev);
+       struct lg_drv_data *drv_data = (struct lg_drv_data *)hid_get_drvdata(hid);
+       struct lg4ff_device_entry *entry;
+       int i, state = 0;
+
+       if (!drv_data) {
+               hid_err(hid, "Device data not found.");
+               return;
+       }
+
+       entry = (struct lg4ff_device_entry *)drv_data->device_props;
+
+       if (!entry) {
+               hid_err(hid, "Device properties not found.");
+               return;
+       }
+
+       for (i = 0; i < 5; i++) {
+               if (led_cdev != entry->led[i])
+                       continue;
+               state = (entry->led_state >> i) & 1;
+               if (value == LED_OFF && state) {
+                       entry->led_state &= ~(1 << i);
+                       lg4ff_set_leds(hid, entry->led_state);
+               } else if (value != LED_OFF && !state) {
+                       entry->led_state |= 1 << i;
+                       lg4ff_set_leds(hid, entry->led_state);
+               }
+               break;
+       }
+}
+
+static enum led_brightness lg4ff_led_get_brightness(struct led_classdev *led_cdev)
+{
+       struct device *dev = led_cdev->dev->parent;
+       struct hid_device *hid = container_of(dev, struct hid_device, dev);
+       struct lg_drv_data *drv_data = (struct lg_drv_data *)hid_get_drvdata(hid);
+       struct lg4ff_device_entry *entry;
+       int i, value = 0;
+
+       if (!drv_data) {
+               hid_err(hid, "Device data not found.");
+               return LED_OFF;
+       }
+
+       entry = (struct lg4ff_device_entry *)drv_data->device_props;
+
+       if (!entry) {
+               hid_err(hid, "Device properties not found.");
+               return LED_OFF;
+       }
+
+       for (i = 0; i < 5; i++)
+               if (led_cdev == entry->led[i]) {
+                       value = (entry->led_state >> i) & 1;
+                       break;
+               }
+
+       return value ? LED_FULL : LED_OFF;
+}
+#endif
+
 int lg4ff_init(struct hid_device *hid)
 {
        struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
@@ -453,6 +538,58 @@ int lg4ff_init(struct hid_device *hid)
        if (entry->set_range != NULL)
                entry->set_range(hid, entry->range);
 
+#ifdef CONFIG_LEDS_CLASS
+       /* register led subsystem - G27 only */
+       entry->led_state = 0;
+       for (j = 0; j < 5; j++)
+               entry->led[j] = NULL;
+
+       if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G27_WHEEL) {
+               struct led_classdev *led;
+               size_t name_sz;
+               char *name;
+
+               lg4ff_set_leds(hid, 0);
+
+               name_sz = strlen(dev_name(&hid->dev)) + 8;
+
+               for (j = 0; j < 5; j++) {
+                       led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
+                       if (!led) {
+                               hid_err(hid, "can't allocate memory for LED %d\n", j);
+                               goto err;
+                       }
+
+                       name = (void *)(&led[1]);
+                       snprintf(name, name_sz, "%s::RPM%d", dev_name(&hid->dev), j+1);
+                       led->name = name;
+                       led->brightness = 0;
+                       led->max_brightness = 1;
+                       led->brightness_get = lg4ff_led_get_brightness;
+                       led->brightness_set = lg4ff_led_set_brightness;
+
+                       entry->led[j] = led;
+                       error = led_classdev_register(&hid->dev, led);
+
+                       if (error) {
+                               hid_err(hid, "failed to register LED %d. Aborting.\n", j);
+err:
+                               /* Deregister LEDs (if any) */
+                               for (j = 0; j < 5; j++) {
+                                       led = entry->led[j];
+                                       entry->led[j] = NULL;
+                                       if (!led)
+                                               continue;
+                                       led_classdev_unregister(led);
+                                       kfree(led);
+                               }
+                               goto out;       /* Let the driver continue without LEDs */
+                       }
+               }
+       }
+#endif
+
+out:
        hid_info(hid, "Force feedback for Logitech Speed Force Wireless by Simon Wood <simon@mungewell.org>\n");
        return 0;
 }
@@ -474,6 +611,25 @@ int lg4ff_deinit(struct hid_device *hid)
                hid_err(hid, "Error while deinitializing device, no device properties data.\n");
                return -1;
        }
+
+#ifdef CONFIG_LEDS_CLASS
+       {
+               int j;
+               struct led_classdev *led;
+
+               /* Deregister LEDs (if any) */
+               for (j = 0; j < 5; j++) {
+
+                       led = entry->led[j];
+                       entry->led[j] = NULL;
+                       if (!led)
+                               continue;
+                       led_classdev_unregister(led);
+                       kfree(led);
+               }
+       }
+#endif
+
        /* Deallocate memory */
        kfree(entry);