HID: nvidia-shield: Support LED functionality for Thunderstrike

Expose the 2017 SHIELD controller (Thunderstrike) LED through the kernel
LED API.

Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-nvidia-shield.c b/drivers/hid/hid-nvidia-shield.c
index d7521c9c8c1e441458a20e56ba9b9ba9c773c759..85700cec5eac6cf5396186161f5bedb160892534 100644 (file)
--- a/drivers/hid/hid-nvidia-shield.c
+++ b/drivers/hid/hid-nvidia-shield.c
@@ -8,6 +8,7 @@
 #include <linux/hid.h>
 #include <linux/input-event-codes.h>
 #include <linux/input.h>
+#include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/workqueue.h>
@@ -35,6 +36,7 @@ enum {
        THUNDERSTRIKE_FW_VERSION_UPDATE = 0,
        THUNDERSTRIKE_BOARD_INFO_UPDATE,
        THUNDERSTRIKE_HAPTICS_UPDATE,
+       THUNDERSTRIKE_LED_UPDATE,
 };
 
 enum {
@@ -45,12 +47,19 @@ enum {
 
 enum {
        THUNDERSTRIKE_HOSTCMD_ID_FW_VERSION = 1,
+       THUNDERSTRIKE_HOSTCMD_ID_LED = 6,
        THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO = 16,
        THUNDERSTRIKE_HOSTCMD_ID_USB_INIT = 53,
        THUNDERSTRIKE_HOSTCMD_ID_HAPTICS = 57,
        THUNDERSTRIKE_HOSTCMD_ID_BLUETOOTH_INIT = 58,
 };
 
+enum thunderstrike_led_state {
+       THUNDERSTRIKE_LED_OFF = 1,
+       THUNDERSTRIKE_LED_ON = 8,
+} __packed;
+static_assert(sizeof(enum thunderstrike_led_state) == 1);
+
 struct thunderstrike_hostcmd_board_info {
        __le16 revision;
        __le16 serial[7];
@@ -70,6 +79,7 @@ struct thunderstrike_hostcmd_resp_report {
                struct thunderstrike_hostcmd_board_info board_info;
                struct thunderstrike_hostcmd_haptics motors;
                __le16 fw_version;
+               enum thunderstrike_led_state led_state;
                u8 payload[30];
        };
 } __packed;
@@ -81,10 +91,16 @@ struct thunderstrike_hostcmd_req_report {
        u8 cmd_id;
        u8 reserved_at_10;
 
-       struct {
-               u8 update;
-               struct thunderstrike_hostcmd_haptics motors;
-       } haptics;
+       union {
+               struct {
+                       u8 update;
+                       enum thunderstrike_led_state state;
+               } led;
+               struct {
+                       u8 update;
+                       struct thunderstrike_hostcmd_haptics motors;
+               } haptics;
+       };
        u8 reserved_at_30[27];
 } __packed;
 static_assert(sizeof(struct thunderstrike_hostcmd_req_report) ==
@@ -108,12 +124,15 @@ struct thunderstrike {
 
        /* Sub-devices */
        struct input_dev *haptics_dev;
+       struct led_classdev led_dev;
 
        /* Resources */
        void *req_report_dmabuf;
        unsigned long update_flags;
        struct thunderstrike_hostcmd_haptics haptics_val;
        spinlock_t haptics_update_lock;
+       u8 led_state : 1;
+       enum thunderstrike_led_state led_value;
        struct work_struct hostcmd_req_work;
 };
 
@@ -221,6 +240,13 @@ static void thunderstrike_hostcmd_req_work_handler(struct work_struct *work)
                thunderstrike_send_hostcmd_request(ts);
        }
 
+       if (test_and_clear_bit(THUNDERSTRIKE_LED_UPDATE, &ts->update_flags)) {
+               thunderstrike_hostcmd_req_report_init(report, THUNDERSTRIKE_HOSTCMD_ID_LED);
+               report->led.update = 1;
+               report->led.state = ts->led_value;
+               thunderstrike_send_hostcmd_request(ts);
+       }
+
        if (test_and_clear_bit(THUNDERSTRIKE_BOARD_INFO_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO);
@@ -292,6 +318,40 @@ static int thunderstrike_play_effect(struct input_dev *idev, void *data,
        return thunderstrike_update_haptics(ts, &motors);
 }
 
+static enum led_brightness
+thunderstrike_led_get_brightness(struct led_classdev *led)
+{
+       struct hid_device *hdev = to_hid_device(led->dev->parent);
+       struct shield_device *shield_dev = hid_get_drvdata(hdev);
+       struct thunderstrike *ts;
+
+       ts = container_of(shield_dev, struct thunderstrike, base);
+
+       return ts->led_state;
+}
+
+static void thunderstrike_led_set_brightness(struct led_classdev *led,
+                                           enum led_brightness value)
+{
+       struct hid_device *hdev = to_hid_device(led->dev->parent);
+       struct shield_device *shield_dev = hid_get_drvdata(hdev);
+       struct thunderstrike *ts;
+
+       ts = container_of(shield_dev, struct thunderstrike, base);
+
+       switch (value) {
+       case LED_OFF:
+               ts->led_value = THUNDERSTRIKE_LED_OFF;
+               break;
+       default:
+               ts->led_value = THUNDERSTRIKE_LED_ON;
+               break;
+       }
+
+       set_bit(THUNDERSTRIKE_LED_UPDATE, &ts->update_flags);
+       schedule_work(&ts->hostcmd_req_work);
+}
+
 static void
 thunderstrike_parse_fw_version_payload(struct shield_device *shield_dev,
                                       __le16 fw_version)
@@ -338,6 +398,24 @@ thunderstrike_parse_haptics_payload(struct shield_device *shield_dev,
                haptics->motor_left, haptics->motor_right);
 }
 
+static void
+thunderstrike_parse_led_payload(struct shield_device *shield_dev,
+                               enum thunderstrike_led_state led_state)
+{
+       struct thunderstrike *ts = container_of(shield_dev, struct thunderstrike, base);
+
+       switch (led_state) {
+       case THUNDERSTRIKE_LED_OFF:
+               ts->led_state = 0;
+               break;
+       case THUNDERSTRIKE_LED_ON:
+               ts->led_state = 1;
+               break;
+       }
+
+       hid_dbg(shield_dev->hdev, "Thunderstrike led HOSTCMD response, 0x%02X\n", led_state);
+}
+
 static int thunderstrike_parse_report(struct shield_device *shield_dev,
                                      struct hid_report *report, u8 *data,
                                      int size)
@@ -364,6 +442,9 @@ static int thunderstrike_parse_report(struct shield_device *shield_dev,
                        thunderstrike_parse_fw_version_payload(
                                shield_dev, hostcmd_resp_report->fw_version);
                        break;
+               case THUNDERSTRIKE_HOSTCMD_ID_LED:
+                       thunderstrike_parse_led_payload(shield_dev, hostcmd_resp_report->led_state);
+                       break;
                case THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO:
                        thunderstrike_parse_board_info_payload(
                                shield_dev, &hostcmd_resp_report->board_info);
@@ -395,10 +476,24 @@ static int thunderstrike_parse_report(struct shield_device *shield_dev,
        return 0;
 }
 
+static inline int thunderstrike_led_create(struct thunderstrike *ts)
+{
+       struct led_classdev *led = &ts->led_dev;
+
+       led->name = "thunderstrike:blue:led";
+       led->max_brightness = 1;
+       led->flags = LED_CORE_SUSPENDRESUME;
+       led->brightness_get = &thunderstrike_led_get_brightness;
+       led->brightness_set = &thunderstrike_led_set_brightness;
+
+       return led_classdev_register(&ts->base.hdev->dev, led);
+}
+
 static struct shield_device *thunderstrike_create(struct hid_device *hdev)
 {
        struct shield_device *shield_dev;
        struct thunderstrike *ts;
+       int ret;
 
        ts = devm_kzalloc(&hdev->dev, sizeof(*ts), GFP_KERNEL);
        if (!ts)
@@ -418,12 +513,22 @@ static struct shield_device *thunderstrike_create(struct hid_device *hdev)
 
        hid_set_drvdata(hdev, shield_dev);
 
+       ret = thunderstrike_led_create(ts);
+       if (ret) {
+               hid_err(hdev, "Failed to create Thunderstrike LED instance\n");
+               return ERR_PTR(ret);
+       }
+
        ts->haptics_dev = shield_haptics_create(shield_dev, thunderstrike_play_effect);
        if (IS_ERR(ts->haptics_dev))
-               return ERR_CAST(ts->haptics_dev);
+               goto err;
 
        hid_info(hdev, "Registered Thunderstrike controller\n");
        return shield_dev;
+
+err:
+       led_classdev_unregister(&ts->led_dev);
+       return ERR_CAST(ts->haptics_dev);
 }
 
 static int android_input_mapping(struct hid_device *hdev, struct hid_input *hi,
@@ -599,6 +704,7 @@ static void shield_remove(struct hid_device *hdev)
        ts = container_of(dev, struct thunderstrike, base);
 
        hid_hw_close(hdev);
+       led_classdev_unregister(&ts->led_dev);
        if (ts->haptics_dev)
                input_unregister_device(ts->haptics_dev);
        cancel_work_sync(&ts->hostcmd_req_work);