Merge branch 'for-5.5/whiskers' into for-linus

- robustification of tablet mode support in google-whiskers
  driver (Dmitry Torokhov)

Author: Jiri Kosina

drivers/hid/hid-google-hammer.c

@@ -35,6 +35,7 @@ struct cbas_ec {
 	struct device *dev;	/* The platform device (EC) */
 	struct input_dev *input;
 	bool base_present;
+	bool base_folded;
 	struct notifier_block notifier;
 };
 
@@ -208,7 +209,14 @@ static int __cbas_ec_probe(struct platform_device *pdev)
 		return error;
 	}
 
-	input_report_switch(input, SW_TABLET_MODE, !cbas_ec.base_present);
+	if (!cbas_ec.base_present)
+		cbas_ec.base_folded = false;
+
+	dev_dbg(&pdev->dev, "%s: base: %d, folded: %d\n", __func__,
+		cbas_ec.base_present, cbas_ec.base_folded);
+
+	input_report_switch(input, SW_TABLET_MODE,
+			    !cbas_ec.base_present || cbas_ec.base_folded);
 
 	cbas_ec_set_input(input);
 
@@ -322,10 +330,9 @@ static int hammer_kbd_brightness_set_blocking(struct led_classdev *cdev,
 static int hammer_register_leds(struct hid_device *hdev)
 {
 	struct hammer_kbd_leds *kbd_backlight;
+	int error;
 
-	kbd_backlight = devm_kzalloc(&hdev->dev,
-				     sizeof(*kbd_backlight),
-				     GFP_KERNEL);
+	kbd_backlight = kzalloc(sizeof(*kbd_backlight), GFP_KERNEL);
 	if (!kbd_backlight)
 		return -ENOMEM;
 
@@ -339,12 +346,31 @@ static int hammer_register_leds(struct hid_device *hdev)
 	/* Set backlight to 0% initially. */
 	hammer_kbd_brightness_set_blocking(&kbd_backlight->cdev, 0);
 
-	return devm_led_classdev_register(&hdev->dev, &kbd_backlight->cdev);
+	error = led_classdev_register(&hdev->dev, &kbd_backlight->cdev);
+	if (error)
+		goto err_free_mem;
+
+	hid_set_drvdata(hdev, kbd_backlight);
+	return 0;
+
+err_free_mem:
+	kfree(kbd_backlight);
+	return error;
+}
+
+static void hammer_unregister_leds(struct hid_device *hdev)
+{
+	struct hammer_kbd_leds *kbd_backlight = hid_get_drvdata(hdev);
+
+	if (kbd_backlight) {
+		led_classdev_unregister(&kbd_backlight->cdev);
+		kfree(kbd_backlight);
+	}
 }
 
 #define HID_UP_GOOGLEVENDOR	0xffd10000
 #define HID_VD_KBD_FOLDED	0x00000019
-#define WHISKERS_KBD_FOLDED	(HID_UP_GOOGLEVENDOR | HID_VD_KBD_FOLDED)
+#define HID_USAGE_KBD_FOLDED	(HID_UP_GOOGLEVENDOR | HID_VD_KBD_FOLDED)
 
 /* HID usage for keyboard backlight (Alphanumeric display brightness) */
 #define HID_AD_BRIGHTNESS	0x00140046
@@ -354,8 +380,7 @@ static int hammer_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 				struct hid_usage *usage,
 				unsigned long **bit, int *max)
 {
-	if (hdev->product == USB_DEVICE_ID_GOOGLE_WHISKERS &&
-	    usage->hid == WHISKERS_KBD_FOLDED) {
+	if (usage->hid == HID_USAGE_KBD_FOLDED) {
 		/*
 		 * We do not want to have this usage mapped as it will get
 		 * mixed in with "base attached" signal and delivered over
@@ -372,19 +397,19 @@ static int hammer_event(struct hid_device *hid, struct hid_field *field,
 {
 	unsigned long flags;
 
-	if (hid->product == USB_DEVICE_ID_GOOGLE_WHISKERS &&
-	    usage->hid == WHISKERS_KBD_FOLDED) {
+	if (usage->hid == HID_USAGE_KBD_FOLDED) {
 		spin_lock_irqsave(&cbas_ec_lock, flags);
 
-		hid_dbg(hid, "%s: base: %d, folded: %d\n", __func__,
-			cbas_ec.base_present, value);
-
 		/*
-		 * We should not get event if base is detached, but in case
-		 * we happen to service HID and EC notifications out of order
-		 * let's still check the "base present" flag.
+		 * If we are getting events from Whiskers that means that it
+		 * is attached to the lid.
 		 */
-		if (cbas_ec.input && cbas_ec.base_present) {
+		cbas_ec.base_present = true;
+		cbas_ec.base_folded = value;
+		hid_dbg(hid, "%s: base: %d, folded: %d\n", __func__,
+			cbas_ec.base_present, cbas_ec.base_folded);
+
+		if (cbas_ec.input) {
 			input_report_switch(cbas_ec.input,
 					    SW_TABLET_MODE, value);
 			input_sync(cbas_ec.input);
@@ -397,55 +422,46 @@ static int hammer_event(struct hid_device *hid, struct hid_field *field,
 	return 0;
 }
 
-static bool hammer_is_keyboard_interface(struct hid_device *hdev)
+static bool hammer_has_usage(struct hid_device *hdev, unsigned int report_type,
+			unsigned application, unsigned usage)
 {
-	struct hid_report_enum *re = &hdev->report_enum[HID_INPUT_REPORT];
-	struct hid_report *report;
-
-	list_for_each_entry(report, &re->report_list, list)
-		if (report->application == HID_GD_KEYBOARD)
-			return true;
-
-	return false;
-}
-
-static bool hammer_has_backlight_control(struct hid_device *hdev)
-{
-	struct hid_report_enum *re = &hdev->report_enum[HID_OUTPUT_REPORT];
+	struct hid_report_enum *re = &hdev->report_enum[report_type];
 	struct hid_report *report;
 	int i, j;
 
 	list_for_each_entry(report, &re->report_list, list) {
-		if (report->application != HID_GD_KEYBOARD)
+		if (report->application != application)
 			continue;
 
 		for (i = 0; i < report->maxfield; i++) {
 			struct hid_field *field = report->field[i];
 
 			for (j = 0; j < field->maxusage; j++)
-				if (field->usage[j].hid == HID_AD_BRIGHTNESS)
+				if (field->usage[j].hid == usage)
 					return true;
 		}
 	}
 
 	return false;
 }
 
+static bool hammer_has_folded_event(struct hid_device *hdev)
+{
+	return hammer_has_usage(hdev, HID_INPUT_REPORT,
+				HID_GD_KEYBOARD, HID_USAGE_KBD_FOLDED);
+}
+
+static bool hammer_has_backlight_control(struct hid_device *hdev)
+{
+	return hammer_has_usage(hdev, HID_OUTPUT_REPORT,
+				HID_GD_KEYBOARD, HID_AD_BRIGHTNESS);
+}
+
 static int hammer_probe(struct hid_device *hdev,
 			const struct hid_device_id *id)
 {
 	int error;
 
-	/*
-	 * We always want to poll for, and handle tablet mode events from
-	 * Whiskers, even when nobody has opened the input device. This also
-	 * prevents the hid core from dropping early tablet mode events from
-	 * the device.
-	 */
-	if (hdev->product == USB_DEVICE_ID_GOOGLE_WHISKERS &&
-			hammer_is_keyboard_interface(hdev))
-		hdev->quirks |= HID_QUIRK_ALWAYS_POLL;
-
 	error = hid_parse(hdev);
 	if (error)
 		return error;
@@ -454,6 +470,19 @@ static int hammer_probe(struct hid_device *hdev,
 	if (error)
 		return error;
 
+	/*
+	 * We always want to poll for, and handle tablet mode events from
+	 * devices that have folded usage, even when nobody has opened the input
+	 * device. This also prevents the hid core from dropping early tablet
+	 * mode events from the device.
+	 */
+	if (hammer_has_folded_event(hdev)) {
+		hdev->quirks |= HID_QUIRK_ALWAYS_POLL;
+		error = hid_hw_open(hdev);
+		if (error)
+			return error;
+	}
+
 	if (hammer_has_backlight_control(hdev)) {
 		error = hammer_register_leds(hdev);
 		if (error)
@@ -465,6 +494,36 @@ static int hammer_probe(struct hid_device *hdev,
 	return 0;
 }
 
+static void hammer_remove(struct hid_device *hdev)
+{
+	unsigned long flags;
+
+	if (hammer_has_folded_event(hdev)) {
+		hid_hw_close(hdev);
+
+		/*
+		 * If we are disconnecting then most likely Whiskers is
+		 * being removed. Even if it is not removed, without proper
+		 * keyboard we should not stay in clamshell mode.
+		 *
+		 * The reason for doing it here and not waiting for signal
+		 * from EC, is that on some devices there are high leakage
+		 * on Whiskers pins and we do not detect disconnect reliably,
+		 * resulting in devices being stuck in clamshell mode.
+		 */
+		spin_lock_irqsave(&cbas_ec_lock, flags);
+		if (cbas_ec.input && cbas_ec.base_present) {
+			input_report_switch(cbas_ec.input, SW_TABLET_MODE, 1);
+			input_sync(cbas_ec.input);
+		}
+		cbas_ec.base_present = false;
+		spin_unlock_irqrestore(&cbas_ec_lock, flags);
+	}
+
+	hammer_unregister_leds(hdev);
+
+	hid_hw_stop(hdev);
+}
 
 static const struct hid_device_id hammer_devices[] = {
 	{ HID_DEVICE(BUS_USB, HID_GROUP_GENERIC,
@@ -487,6 +546,7 @@ static struct hid_driver hammer_driver = {
 	.name = "hammer",
 	.id_table = hammer_devices,
 	.probe = hammer_probe,
+	.remove = hammer_remove,
 	.input_mapping = hammer_input_mapping,
 	.event = hammer_event,
 };