1 files changed, 312 insertions, 0 deletions
diff --git a/drivers/hid/hid-cougar.c b/drivers/hid/hid-cougar.c
new file mode 100644
index 000000000000..ad2e87de7dc5
--- /dev/null
+++ b/drivers/hid/hid-cougar.c
@@ -0,0 +1,312 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  HID driver for Cougar 500k Gaming Keyboard
+ *
+ *  Copyright (c) 2018 Daniel M. Lambea <dmlambea@gmail.com>
+ */
+
+#include <linux/hid.h>
+#include <linux/module.h>
+
+#include "hid-ids.h"
+
+MODULE_AUTHOR("Daniel M. Lambea <dmlambea@gmail.com>");
+MODULE_DESCRIPTION("Cougar 500k Gaming Keyboard");
+MODULE_LICENSE("GPL");
+MODULE_INFO(key_mappings, "G1-G6 are mapped to F13-F18");
+
+static int cougar_g6_is_space = 1;
+module_param_named(g6_is_space, cougar_g6_is_space, int, 0600);
+MODULE_PARM_DESC(g6_is_space,
+	"If set, G6 programmable key sends SPACE instead of F18 (0=off, 1=on) (default=1)");
+
+
+#define COUGAR_VENDOR_USAGE	0xff00ff00
+
+#define COUGAR_FIELD_CODE	1
+#define COUGAR_FIELD_ACTION	2
+
+#define COUGAR_KEY_G1		0x83
+#define COUGAR_KEY_G2		0x84
+#define COUGAR_KEY_G3		0x85
+#define COUGAR_KEY_G4		0x86
+#define COUGAR_KEY_G5		0x87
+#define COUGAR_KEY_G6		0x78
+#define COUGAR_KEY_FN		0x0d
+#define COUGAR_KEY_MR		0x6f
+#define COUGAR_KEY_M1		0x80
+#define COUGAR_KEY_M2		0x81
+#define COUGAR_KEY_M3		0x82
+#define COUGAR_KEY_LEDS		0x67
+#define COUGAR_KEY_LOCK		0x6e
+
+
+/* Default key mappings. The special key COUGAR_KEY_G6 is defined first
+ * because it is more frequent to use the spacebar rather than any other
+ * special keys. Depending on the value of the parameter 'g6_is_space',
+ * the mapping will be updated in the probe function.
+ */
+static unsigned char cougar_mapping[][2] = {
+	{ COUGAR_KEY_G6,   KEY_SPACE },
+	{ COUGAR_KEY_G1,   KEY_F13 },
+	{ COUGAR_KEY_G2,   KEY_F14 },
+	{ COUGAR_KEY_G3,   KEY_F15 },
+	{ COUGAR_KEY_G4,   KEY_F16 },
+	{ COUGAR_KEY_G5,   KEY_F17 },
+	{ COUGAR_KEY_LOCK, KEY_SCREENLOCK },
+/* The following keys are handled by the hardware itself, so no special
+ * treatment is required:
+	{ COUGAR_KEY_FN, KEY_RESERVED },
+	{ COUGAR_KEY_MR, KEY_RESERVED },
+	{ COUGAR_KEY_M1, KEY_RESERVED },
+	{ COUGAR_KEY_M2, KEY_RESERVED },
+	{ COUGAR_KEY_M3, KEY_RESERVED },
+	{ COUGAR_KEY_LEDS, KEY_RESERVED },
+*/
+	{ 0, 0 },
+};
+
+struct cougar_shared {
+	struct list_head list;
+	struct kref kref;
+	bool enabled;
+	struct hid_device *dev;
+	struct input_dev *input;
+};
+
+struct cougar {
+	bool special_intf;
+	struct cougar_shared *shared;
+};
+
+static LIST_HEAD(cougar_udev_list);
+static DEFINE_MUTEX(cougar_udev_list_lock);
+
+static void cougar_fix_g6_mapping(struct hid_device *hdev)
+{
+	int i;
+
+	for (i = 0; cougar_mapping[i][0]; i++) {
+		if (cougar_mapping[i][0] == COUGAR_KEY_G6) {
+			cougar_mapping[i][1] =
+				cougar_g6_is_space ? KEY_SPACE : KEY_F18;
+			hid_info(hdev, "G6 mapped to %s\n",
+				 cougar_g6_is_space ? "space" : "F18");
+			return;
+		}
+	}
+	hid_warn(hdev, "no mapping defined for G6/spacebar");
+}
+
+/*
+ * Constant-friendly rdesc fixup for mouse interface
+ */
+static __u8 *cougar_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+				 unsigned int *rsize)
+{
+	if (rdesc[2] == 0x09 && rdesc[3] == 0x02 &&
+	    (rdesc[115] | rdesc[116] << 8) >= HID_MAX_USAGES) {
+		hid_info(hdev,
+			"usage count exceeds max: fixing up report descriptor\n");
+		rdesc[115] = ((HID_MAX_USAGES-1) & 0xff);
+		rdesc[116] = ((HID_MAX_USAGES-1) >> 8);
+	}
+	return rdesc;
+}
+
+static struct cougar_shared *cougar_get_shared_data(struct hid_device *hdev)
+{
+	struct cougar_shared *shared;
+
+	/* Try to find an already-probed interface from the same device */
+	list_for_each_entry(shared, &cougar_udev_list, list) {
+		if (hid_compare_device_paths(hdev, shared->dev, '/')) {
+			kref_get(&shared->kref);
+			return shared;
+		}
+	}
+	return NULL;
+}
+
+static void cougar_release_shared_data(struct kref *kref)
+{
+	struct cougar_shared *shared = container_of(kref,
+						    struct cougar_shared, kref);
+
+	mutex_lock(&cougar_udev_list_lock);
+	list_del(&shared->list);
+	mutex_unlock(&cougar_udev_list_lock);
+
+	kfree(shared);
+}
+
+static void cougar_remove_shared_data(void *resource)
+{
+	struct cougar *cougar = resource;
+
+	if (cougar->shared) {
+		kref_put(&cougar->shared->kref, cougar_release_shared_data);
+		cougar->shared = NULL;
+	}
+}
+
+/*
+ * Bind the device group's shared data to this cougar struct.
+ * If no shared data exists for this group, create and initialize it.
+ */
+static int cougar_bind_shared_data(struct hid_device *hdev, struct cougar *cougar)
+{
+	struct cougar_shared *shared;
+	int error = 0;
+
+	mutex_lock(&cougar_udev_list_lock);
+
+	shared = cougar_get_shared_data(hdev);
+	if (!shared) {
+		shared = kzalloc(sizeof(*shared), GFP_KERNEL);
+		if (!shared) {
+			error = -ENOMEM;
+			goto out;
+		}
+
+		kref_init(&shared->kref);
+		shared->dev = hdev;
+		list_add_tail(&shared->list, &cougar_udev_list);
+	}
+
+	cougar->shared = shared;
+
+	error = devm_add_action(&hdev->dev, cougar_remove_shared_data, cougar);
+	if (error) {
+		mutex_unlock(&cougar_udev_list_lock);
+		cougar_remove_shared_data(cougar);
+		return error;
+	}
+
+out:
+	mutex_unlock(&cougar_udev_list_lock);
+	return error;
+}
+
+static int cougar_probe(struct hid_device *hdev,
+			const struct hid_device_id *id)
+{
+	struct cougar *cougar;
+	struct hid_input *next, *hidinput = NULL;
+	unsigned int connect_mask;
+	int error;
+
+	cougar = devm_kzalloc(&hdev->dev, sizeof(*cougar), GFP_KERNEL);
+	if (!cougar)
+		return -ENOMEM;
+	hid_set_drvdata(hdev, cougar);
+
+	error = hid_parse(hdev);
+	if (error) {
+		hid_err(hdev, "parse failed\n");
+		goto fail;
+	}
+
+	if (hdev->collection->usage == COUGAR_VENDOR_USAGE) {
+		cougar->special_intf = true;
+		connect_mask = HID_CONNECT_HIDRAW;
+	} else
+		connect_mask = HID_CONNECT_DEFAULT;
+
+	error = hid_hw_start(hdev, connect_mask);
+	if (error) {
+		hid_err(hdev, "hw start failed\n");
+		goto fail;
+	}
+
+	error = cougar_bind_shared_data(hdev, cougar);
+	if (error)
+		goto fail_stop_and_cleanup;
+
+	/* The custom vendor interface will use the hid_input registered
+	 * for the keyboard interface, in order to send translated key codes
+	 * to it.
+	 */
+	if (hdev->collection->usage == HID_GD_KEYBOARD) {
+		cougar_fix_g6_mapping(hdev);
+		list_for_each_entry_safe(hidinput, next, &hdev->inputs, list) {
+			if (hidinput->registered && hidinput->input != NULL) {
+				cougar->shared->input = hidinput->input;
+				cougar->shared->enabled = true;
+				break;
+			}
+		}
+	} else if (hdev->collection->usage == COUGAR_VENDOR_USAGE) {
+		error = hid_hw_open(hdev);
+		if (error)
+			goto fail_stop_and_cleanup;
+	}
+	return 0;
+
+fail_stop_and_cleanup:
+	hid_hw_stop(hdev);
+fail:
+	hid_set_drvdata(hdev, NULL);
+	return error;
+}
+
+/*
+ * Convert events from vendor intf to input key events
+ */
+static int cougar_raw_event(struct hid_device *hdev, struct hid_report *report,
+			    u8 *data, int size)
+{
+	struct cougar *cougar;
+	unsigned char code, action;
+	int i;
+
+	cougar = hid_get_drvdata(hdev);
+	if (!cougar->special_intf || !cougar->shared ||
+	    !cougar->shared->input || !cougar->shared->enabled)
+		return 0;
+
+	code = data[COUGAR_FIELD_CODE];
+	action = data[COUGAR_FIELD_ACTION];
+	for (i = 0; cougar_mapping[i][0]; i++) {
+		if (code == cougar_mapping[i][0]) {
+			input_event(cougar->shared->input, EV_KEY,
+				    cougar_mapping[i][1], action);
+			input_sync(cougar->shared->input);
+			return 0;
+		}
+	}
+	hid_warn(hdev, "unmapped special key code %x: ignoring\n", code);
+	return 0;
+}
+
+static void cougar_remove(struct hid_device *hdev)
+{
+	struct cougar *cougar = hid_get_drvdata(hdev);
+
+	if (cougar) {
+		/* Stop the vendor intf to process more events */
+		if (cougar->shared)
+			cougar->shared->enabled = false;
+		if (cougar->special_intf)
+			hid_hw_close(hdev);
+	}
+	hid_hw_stop(hdev);
+}
+
+static struct hid_device_id cougar_id_table[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_SOLID_YEAR,
+			 USB_DEVICE_ID_COUGAR_500K_GAMING_KEYBOARD) },
+	{}
+};
+MODULE_DEVICE_TABLE(hid, cougar_id_table);
+
+static struct hid_driver cougar_driver = {
+	.name			= "cougar",
+	.id_table		= cougar_id_table,
+	.report_fixup		= cougar_report_fixup,
+	.probe			= cougar_probe,
+	.remove			= cougar_remove,
+	.raw_event		= cougar_raw_event,
+};
+
+module_hid_driver(cougar_driver);