HID: hid, make parsing event driven

Next step for complete hid bus, this patch includes:
- call parser either from probe or from hid-core if there is no probe.
- add ll_driver structure and centralize some stuff there (open, close...)
- split and merge usb_hid_configure and hid_probe into several functions
  to allow hooks/fixes between them
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-core.c

@@ -648,6 +648,9 @@ int hid_parse_report(struct hid_device *device, __u8 *start,
 		hid_parser_reserved
 	};
 
+	if (device->driver->report_fixup)
+		device->driver->report_fixup(device, start, size);
+
 	device->rdesc = kmalloc(size, GFP_KERNEL);
 	if (device->rdesc == NULL)
 		return -ENOMEM;
@@ -1152,15 +1155,20 @@ static int hid_device_probe(struct device *dev)
 	int ret = 0;
 
 	if (!hdev->driver) {
-		if (hdrv->probe) {
-			ret = -ENODEV;
+		id = hid_match_id(hdev, hdrv->id_table);
+		if (id == NULL)
+			return -ENODEV;
 
-			id = hid_match_id(hdev, hdrv->id_table);
-			if (id)
-				ret = hdrv->probe(hdev, id);
+		hdev->driver = hdrv;
+		if (hdrv->probe) {
+			ret = hdrv->probe(hdev, id);
+		} else { /* default probe */
+			ret = hid_parse(hdev);
+			if (!ret)
+				ret = hid_hw_start(hdev);
 		}
-		if (!ret)
-			hdev->driver = hdrv;
+		if (ret)
+			hdev->driver = NULL;
 	}
 	return ret;
 }
@@ -1173,6 +1181,8 @@ static int hid_device_remove(struct device *dev)
 	if (hdrv) {
 		if (hdrv->remove)
 			hdrv->remove(hdev);
+		else /* default remove */
+			hid_hw_stop(hdev);
 		hdev->driver = NULL;
 	}
 

drivers/hid/hid-input.c

@@ -390,6 +390,15 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 	if (ret)
 		goto mapped;
 
+	if (device->driver->input_mapping) {
+		int ret = device->driver->input_mapping(device, hidinput, field,
+				usage, &bit, &max);
+		if (ret > 0)
+			goto mapped;
+		if (ret < 0)
+			goto ignore;
+	}
+
 	switch (usage->hid & HID_USAGE_PAGE) {
 
 		case HID_UP_UNDEFINED:
@@ -755,6 +764,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 	}
 
 mapped:
+	if (device->driver->input_mapped && device->driver->input_mapped(device,
+				hidinput, field, usage, &bit, &max) < 0)
+		goto ignore;
+
 	if (device->quirks & HID_QUIRK_MIGHTYMOUSE) {
 		if (usage->hid == HID_GD_Z)
 			map_rel(REL_HWHEEL);
@@ -961,14 +974,14 @@ static int hidinput_open(struct input_dev *dev)
 {
 	struct hid_device *hid = input_get_drvdata(dev);
 
-	return hid->hid_open(hid);
+	return hid->ll_driver->open(hid);
 }
 
 static void hidinput_close(struct input_dev *dev)
 {
 	struct hid_device *hid = input_get_drvdata(dev);
 
-	hid->hid_close(hid);
+	hid->ll_driver->close(hid);
 }
 
 /*
@@ -1019,7 +1032,8 @@ int hidinput_connect(struct hid_device *hid)
 				}
 
 				input_set_drvdata(input_dev, hid);
-				input_dev->event = hid->hidinput_input_event;
+				input_dev->event =
+					hid->ll_driver->hidinput_input_event;
 				input_dev->open = hidinput_open;
 				input_dev->close = hidinput_close;
 				input_dev->setkeycode = hidinput_setkeycode;

drivers/hid/hidraw.c

@@ -181,7 +181,7 @@ static int hidraw_open(struct inode *inode, struct file *file)
 
 	dev = hidraw_table[minor];
 	if (!dev->open++)
-		dev->hid->hid_open(dev->hid);
+		dev->hid->ll_driver->open(dev->hid);
 
 out_unlock:
 	spin_unlock(&minors_lock);
@@ -207,7 +207,7 @@ static int hidraw_release(struct inode * inode, struct file * file)
 	dev = hidraw_table[minor];
 	if (!dev->open--) {
 		if (list->hidraw->exist)
-			dev->hid->hid_close(dev->hid);
+			dev->hid->ll_driver->close(dev->hid);
 		else
 			kfree(list->hidraw);
 	}
@@ -367,7 +367,7 @@ void hidraw_disconnect(struct hid_device *hid)
 	device_destroy(hidraw_class, MKDEV(hidraw_major, hidraw->minor));
 
 	if (hidraw->open) {
-		hid->hid_close(hid);
+		hid->ll_driver->close(hid);
 		wake_up_interruptible(&hidraw->wait);
 	} else {
 		kfree(hidraw);

include/linux/hid.h

@@ -419,6 +419,7 @@ struct hid_control_fifo {
 #define HID_CLAIMED_HIDRAW	4
 
 #define HID_STAT_ADDED		1
+#define HID_STAT_PARSED		2
 
 #define HID_CTRL_RUNNING	1
 #define HID_OUT_RUNNING		2
@@ -435,6 +436,7 @@ struct hid_input {
 };
 
 struct hid_driver;
+struct hid_ll_driver;
 
 struct hid_device {							/* device report descriptor */
 	__u8 *rdesc;
@@ -452,6 +454,7 @@ struct hid_device {							/* device report descriptor */
 
 	struct device dev;						/* device */
 	struct hid_driver *driver;
+	struct hid_ll_driver *ll_driver;
 
 	unsigned int status;						/* see STAT flags above */
 	unsigned claimed;						/* Claimed by hidinput, hiddev? */
@@ -471,11 +474,6 @@ struct hid_device {							/* device report descriptor */
 
 	__s32 delayed_value;						/* For A4 Tech mice hwheel quirk */
 
-	/* device-specific function pointers */
-	int (*hidinput_input_event) (struct input_dev *, unsigned int, unsigned int, int);
-	int (*hid_open) (struct hid_device *);
-	void (*hid_close) (struct hid_device *);
-
 	/* hiddev event handler */
 	void (*hiddev_hid_event) (struct hid_device *, struct hid_field *field,
 				  struct hid_usage *, __s32);
@@ -561,9 +559,22 @@ struct hid_usage_id {
  * @raw_event: if report in report_table, this hook is called (NULL means nop)
  * @usage_table: on which events to call event (NULL means all)
  * @event: if usage in usage_table, this hook is called (NULL means nop)
+ * @report_fixup: called before report descriptor parsing (NULL means nop)
+ * @input_mapping: invoked on input registering before mapping an usage
+ * @input_mapped: invoked on input registering after mapping an usage
  *
  * raw_event and event should return 0 on no action performed, 1 when no
  * further processing should be done and negative on error
+ *
+ * input_mapping shall return a negative value to completely ignore this usage
+ * (e.g. doubled or invalid usage), zero to continue with parsing of this
+ * usage by generic code (no special handling needed) or positive to skip
+ * generic parsing (needed special handling which was done in the hook already)
+ * input_mapped shall return negative to inform the layer that this usage
+ * should not be considered for further processing or zero to notify that
+ * no processing was performed and should be done in a generic manner
+ * Both these functions may be NULL which means the same behavior as returning
+ * zero from them.
  */
 struct hid_driver {
 	char *name;
@@ -578,10 +589,43 @@ struct hid_driver {
 	const struct hid_usage_id *usage_table;
 	int (*event)(struct hid_device *hdev, struct hid_field *field,
 			struct hid_usage *usage, __s32 value);
+
+	void (*report_fixup)(struct hid_device *hdev, __u8 *buf,
+			unsigned int size);
+
+	int (*input_mapping)(struct hid_device *hdev,
+			struct hid_input *hidinput, struct hid_field *field,
+			struct hid_usage *usage, unsigned long **bit, int *max);
+	int (*input_mapped)(struct hid_device *hdev,
+			struct hid_input *hidinput, struct hid_field *field,
+			struct hid_usage *usage, unsigned long **bit, int *max);
 /* private: */
 	struct device_driver driver;
 };
 
+/**
+ * hid_ll_driver - low level driver callbacks
+ * @start: called on probe to start the device
+ * @stop: called on remove
+ * @open: called by input layer on open
+ * @close: called by input layer on close
+ * @hidinput_input_event: event input event (e.g. ff or leds)
+ * @parse: this method is called only once to parse the device data,
+ *	   shouldn't allocate anything to not leak memory
+ */
+struct hid_ll_driver {
+	int (*start)(struct hid_device *hdev);
+	void (*stop)(struct hid_device *hdev);
+
+	int (*open)(struct hid_device *hdev);
+	void (*close)(struct hid_device *hdev);
+
+	int (*hidinput_input_event) (struct input_dev *idev, unsigned int type,
+			unsigned int code, int value);
+
+	int (*parse)(struct hid_device *hdev);
+};
+
 /* Applications from HID Usage Tables 4/8/99 Version 1.1 */
 /* We ignore a few input applications that are not widely used */
 #define IS_INPUT_APPLICATION(a) (((a >= 0x00010000) && (a <= 0x00010008)) || (a == 0x00010080) || (a == 0x000c0001) || (a == 0x000d0002))
@@ -618,6 +662,56 @@ void hid_output_report(struct hid_report *report, __u8 *data);
 struct hid_device *hid_allocate_device(void);
 int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size);
 
+/**
+ * hid_parse - parse HW reports
+ *
+ * @hdev: hid device
+ *
+ * Call this from probe after you set up the device (if needed). Your
+ * report_fixup will be called (if non-NULL) after reading raw report from
+ * device before passing it to hid layer for real parsing.
+ */
+static inline int __must_check hid_parse(struct hid_device *hdev)
+{
+	int ret;
+
+	if (hdev->status & HID_STAT_PARSED)
+		return 0;
+
+	ret = hdev->ll_driver->parse(hdev);
+	if (!ret)
+		hdev->status |= HID_STAT_PARSED;
+
+	return ret;
+}
+
+/**
+ * hid_hw_start - start underlaying HW
+ *
+ * @hdev: hid device
+ *
+ * Call this in probe function *after* hid_parse. This will setup HW buffers
+ * and start the device (if not deffered to device open). hid_hw_stop must be
+ * called if this was successfull.
+ */
+static inline int __must_check hid_hw_start(struct hid_device *hdev)
+{
+	return hdev->ll_driver->start(hdev);
+}
+
+/**
+ * hid_hw_stop - stop underlaying HW
+ *
+ * @hdev: hid device
+ *
+ * This is usually called from remove function or from probe when something
+ * failed and hid_hw_start was called already.
+ */
+static inline void hid_hw_stop(struct hid_device *hdev)
+{
+	hdev->ll_driver->stop(hdev);
+}
+
 void hid_report_raw_event(struct hid_device *hid, int type, u8 *data, int size,
 		int interrupt);
 

net/bluetooth/hidp/core.c

@@ -623,9 +623,15 @@ static struct device *hidp_get_device(struct hidp_session *session)
 static int hidp_setup_input(struct hidp_session *session,
 				struct hidp_connadd_req *req)
 {
-	struct input_dev *input = session->input;
+	struct input_dev *input;
 	int i;
 
+	input = input_allocate_device();
+	if (!input)
+		return -ENOMEM;
+
+	session->input = input;
+
 	input_set_drvdata(input, session);
 
 	input->name = "Bluetooth HID Boot Protocol Device";
@@ -698,55 +704,117 @@ static void hidp_setup_quirks(struct hid_device *hid)
 			hid->quirks = hidp_blacklist[n].quirks;
 }
 
+static int hidp_parse(struct hid_device *hid)
+{
+	struct hidp_session *session = hid->driver_data;
+	struct hidp_connadd_req *req = session->req;
+	unsigned char *buf;
+	int ret;
+
+	buf = kmalloc(req->rd_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, req->rd_data, req->rd_size)) {
+		kfree(buf);
+		return -EFAULT;
+	}
+
+	ret = hid_parse_report(session->hid, buf, req->rd_size);
+
+	kfree(buf);
+
+	if (ret)
+		return ret;
+
+	session->req = NULL;
+
+	hidp_setup_quirks(hid);
+	return 0;
+}
+
+static int hidp_start(struct hid_device *hid)
+{
+	struct hidp_session *session = hid->driver_data;
+	struct hid_report *report;
+
+	list_for_each_entry(report, &hid->report_enum[HID_INPUT_REPORT].
+			report_list, list)
+		hidp_send_report(session, report);
+
+	list_for_each_entry(report, &hid->report_enum[HID_FEATURE_REPORT].
+			report_list, list)
+		hidp_send_report(session, report);
+
+	if (hidinput_connect(hid) == 0)
+		hid->claimed |= HID_CLAIMED_INPUT;
+
+	return 0;
+}
+
+static void hidp_stop(struct hid_device *hid)
+{
+	struct hidp_session *session = hid->driver_data;
+
+	skb_queue_purge(&session->ctrl_transmit);
+	skb_queue_purge(&session->intr_transmit);
+
+	if (hid->claimed & HID_CLAIMED_INPUT)
+		hidinput_disconnect(hid);
+	hid->claimed = 0;
+}
+
+static struct hid_ll_driver hidp_hid_driver = {
+	.parse = hidp_parse,
+	.start = hidp_start,
+	.stop = hidp_stop,
+	.open  = hidp_open,
+	.close = hidp_close,
+	.hidinput_input_event = hidp_hidinput_event,
+};
+
 static int hidp_setup_hid(struct hidp_session *session,
 				struct hidp_connadd_req *req)
 {
-	struct hid_device *hid = session->hid;
-	struct hid_report *report;
+	struct hid_device *hid;
 	bdaddr_t src, dst;
 	int ret;
 
-	baswap(&src, &bt_sk(session->ctrl_sock->sk)->src);
-	baswap(&dst, &bt_sk(session->ctrl_sock->sk)->dst);
+	hid = hid_allocate_device();
+	if (IS_ERR(hid)) {
+		ret = PTR_ERR(session->hid);
+		goto err;
+	}
 
+	session->hid = hid;
+	session->req = req;
 	hid->driver_data = session;
 
-	hid->country = req->country;
+	baswap(&src, &bt_sk(session->ctrl_sock->sk)->src);
+	baswap(&dst, &bt_sk(session->ctrl_sock->sk)->dst);
 
 	hid->bus     = BUS_BLUETOOTH;
 	hid->vendor  = req->vendor;
 	hid->product = req->product;
 	hid->version = req->version;
+	hid->country = req->country;
 
 	strncpy(hid->name, req->name, 128);
 	strncpy(hid->phys, batostr(&src), 64);
 	strncpy(hid->uniq, batostr(&dst), 64);
 
 	hid->dev.parent = hidp_get_device(session);
-
-	hid->hid_open  = hidp_open;
-	hid->hid_close = hidp_close;
-
-	hid->hidinput_input_event = hidp_hidinput_event;
-
-	hidp_setup_quirks(hid);
-
-	list_for_each_entry(report, &hid->report_enum[HID_INPUT_REPORT].report_list, list)
-		hidp_send_report(session, report);
-
-	list_for_each_entry(report, &hid->report_enum[HID_FEATURE_REPORT].report_list, list)
-		hidp_send_report(session, report);
-
-	if (hidinput_connect(hid) == 0)
-		hid->claimed |= HID_CLAIMED_INPUT;
+	hid->ll_driver = &hidp_hid_driver;
 
 	ret = hid_add_device(hid);
-	if (ret) {
-		if (hid->claimed & HID_CLAIMED_INPUT)
-			hidinput_disconnect(hid);
-		skb_queue_purge(&session->intr_transmit);
-	}
+	if (ret)
+		goto err_hid;
 
+	return 0;
+err_hid:
+	hid_destroy_device(hid);
+	session->hid = NULL;
+err:
 	return ret;
 }
 
@@ -767,46 +835,6 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
 
 	BT_DBG("rd_data %p rd_size %d", req->rd_data, req->rd_size);
 
-	if (req->rd_size > 0) {
-		unsigned char *buf = kmalloc(req->rd_size, GFP_KERNEL);
-
-		if (!buf) {
-			kfree(session);
-			return -ENOMEM;
-		}
-
-		if (copy_from_user(buf, req->rd_data, req->rd_size)) {
-			kfree(buf);
-			kfree(session);
-			return -EFAULT;
-		}
-
-		session->hid = hid_allocate_device();
-		if (IS_ERR(session->hid)) {
-			kfree(buf);
-			kfree(session);
-			return PTR_ERR(session->hid);
-		}
-
-		err = hid_parse_report(session->hid, buf, req->rd_size);
-
-		kfree(buf);
-
-		if (err) {
-			hid_destroy_device(session->hid);
-			kfree(session);
-			return -EINVAL;
-		}
-	}
-
-	if (!session->hid) {
-		session->input = input_allocate_device();
-		if (!session->input) {
-			kfree(session);
-			return -ENOMEM;
-		}
-	}
-
 	down_write(&hidp_session_sem);
 
 	s = __hidp_get_session(&bt_sk(ctrl_sock->sk)->dst);
@@ -834,16 +862,16 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
 	session->flags   = req->flags & (1 << HIDP_BLUETOOTH_VENDOR_ID);
 	session->idle_to = req->idle_to;
 
-	if (session->input) {
-		err = hidp_setup_input(session, req);
-		if (err < 0)
-			goto failed;
-	}
-
-	if (session->hid) {
+	if (req->rd_size > 0) {
 		err = hidp_setup_hid(session, req);
 		if (err)
-			goto failed;
+			goto err_skb;
+	}
+
+	if (!session->hid) {
+		err = hidp_setup_input(session, req);
+		if (err < 0)
+			goto err_skb;
 	}
 
 	__hidp_link_session(session);
@@ -871,16 +899,15 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
 
 	__hidp_unlink_session(session);
 
-	if (session->input) {
+	if (session->input)
 		input_unregister_device(session->input);
-		session->input = NULL; /* don't try to free it here */
-	}
-
-failed:
-	up_write(&hidp_session_sem);
-
 	if (session->hid)
 		hid_destroy_device(session->hid);
+err_skb:
+	skb_queue_purge(&session->ctrl_transmit);
+	skb_queue_purge(&session->intr_transmit);
+failed:
+	up_write(&hidp_session_sem);
 
 	input_free_device(session->input);
 	kfree(session);

net/bluetooth/hidp/hidp.h

@@ -151,6 +151,8 @@ struct hidp_session {
 
 	struct sk_buff_head ctrl_transmit;
 	struct sk_buff_head intr_transmit;
+
+	struct hidp_connadd_req *req;
 };
 
 static inline void hidp_schedule(struct hidp_session *session)