HID: bt: Add support for hidraw HIDIOCGFEATURE and HIDIOCSFEATURE

This patch adds support or getting and setting feature reports for bluetooth
HID devices from HIDRAW.

Signed-off-by: Alan Ott <alan@signal11.us>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

2 files changed, 117 insertions, 4 deletions

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 5383e6c7d09d..6df8ea1c6341 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -36,6 +36,7 @@
 #include <linux/file.h>
 #include <linux/init.h>
 #include <linux/wait.h>
+#include <linux/mutex.h>
 #include <net/sock.h>
 
 #include <linux/input.h>
@@ -313,6 +314,86 @@ static int hidp_send_report(struct hidp_session *session, struct hid_report *rep
         return hidp_queue_report(session, buf, rsize);
 }
 
+static int hidp_get_raw_report(struct hid_device *hid,
+                unsigned char report_number,
+                unsigned char *data, size_t count,
+                unsigned char report_type)
+{
+        struct hidp_session *session = hid->driver_data;
+        struct sk_buff *skb;
+        size_t len;
+        int numbered_reports = hid->report_enum[report_type].numbered;
+
+        switch (report_type) {
+        case HID_FEATURE_REPORT:
+                report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_FEATURE;
+                break;
+        case HID_INPUT_REPORT:
+                report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_INPUT;
+                break;
+        case HID_OUTPUT_REPORT:
+                report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_OUPUT;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        if (mutex_lock_interruptible(&session->report_mutex))
+                return -ERESTARTSYS;
+
+        /* Set up our wait, and send the report request to the device. */
+        session->waiting_report_type = report_type & HIDP_DATA_RTYPE_MASK;
+        session->waiting_report_number = numbered_reports ? report_number : -1;
+        set_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+        data[0] = report_number;
+        if (hidp_send_ctrl_message(hid->driver_data, report_type, data, 1))
+                goto err_eio;
+
+        /* Wait for the return of the report. The returned report
+           gets put in session->report_return.  */
+        while (test_bit(HIDP_WAITING_FOR_RETURN, &session->flags)) {
+                int res;
+
+                res = wait_event_interruptible_timeout(session->report_queue,
+                        !test_bit(HIDP_WAITING_FOR_RETURN, &session->flags),
+                        5*HZ);
+                if (res == 0) {
+                        /* timeout */
+                        goto err_eio;
+                }
+                if (res < 0) {
+                        /* signal */
+                        goto err_restartsys;
+                }
+        }
+
+        skb = session->report_return;
+        if (skb) {
+                len = skb->len < count ? skb->len : count;
+                memcpy(data, skb->data, len);
+
+                kfree_skb(skb);
+                session->report_return = NULL;
+        } else {
+                /* Device returned a HANDSHAKE, indicating  protocol error. */
+                len = -EIO;
+        }
+
+        clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+        mutex_unlock(&session->report_mutex);
+
+        return len;
+
+err_restartsys:
+        clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+        mutex_unlock(&session->report_mutex);
+        return -ERESTARTSYS;
+err_eio:
+        clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+        mutex_unlock(&session->report_mutex);
+        return -EIO;
+}
+
 static int hidp_output_raw_report(struct hid_device *hid, unsigned char *data, size_t count,
                 unsigned char report_type)
 {
@@ -409,6 +490,10 @@ static void hidp_process_handshake(struct hidp_session *session,
         case HIDP_HSHK_ERR_INVALID_REPORT_ID:
         case HIDP_HSHK_ERR_UNSUPPORTED_REQUEST:
         case HIDP_HSHK_ERR_INVALID_PARAMETER:
+                if (test_bit(HIDP_WAITING_FOR_RETURN, &session->flags)) {
+                        clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+                        wake_up_interruptible(&session->report_queue);
+                }
                 /* FIXME: Call into SET_ GET_ handlers here */
                 break;
 
@@ -451,9 +536,11 @@ static void hidp_process_hid_control(struct hidp_session *session,
         }
 }
 
-static void hidp_process_data(struct hidp_session *session, struct sk_buff *skb,
+/* Returns true if the passed-in skb should be freed by the caller. */
+static int hidp_process_data(struct hidp_session *session, struct sk_buff *skb,
                                 unsigned char param)
 {
+        int done_with_skb = 1;
         BT_DBG("session %p skb %p len %d param 0x%02x", session, skb, skb->len, param);
 
         switch (param) {
@@ -465,7 +552,6 @@ static void hidp_process_data(struct hidp_session *session, struct sk_buff *skb,
 
                 if (session->hid)
                         hid_input_report(session->hid, HID_INPUT_REPORT, skb->data, skb->len, 0);
-
                 break;
 
         case HIDP_DATA_RTYPE_OTHER:
@@ -477,12 +563,27 @@ static void hidp_process_data(struct hidp_session *session, struct sk_buff *skb,
                 __hidp_send_ctrl_message(session,
                         HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
         }
+
+        if (test_bit(HIDP_WAITING_FOR_RETURN, &session->flags) &&
+                                param == session->waiting_report_type) {
+                if (session->waiting_report_number < 0 ||
+                    session->waiting_report_number == skb->data[0]) {
+                        /* hidp_get_raw_report() is waiting on this report. */
+                        session->report_return = skb;
+                        done_with_skb = 0;
+                        clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
+                        wake_up_interruptible(&session->report_queue);
+                }
+        }
+
+        return done_with_skb;
 }
 
 static void hidp_recv_ctrl_frame(struct hidp_session *session,
                                         struct sk_buff *skb)
 {
         unsigned char hdr, type, param;
+        int free_skb = 1;
 
         BT_DBG("session %p skb %p len %d", session, skb, skb->len);
 
@@ -502,7 +603,7 @@ static void hidp_recv_ctrl_frame(struct hidp_session *session,
                 break;
 
         case HIDP_TRANS_DATA:
-                hidp_process_data(session, skb, param);
+                free_skb = hidp_process_data(session, skb, param);
                 break;
 
         default:
@@ -511,7 +612,8 @@ static void hidp_recv_ctrl_frame(struct hidp_session *session,
                 break;
         }
 
-        kfree_skb(skb);
+        if (free_skb)
+                kfree_skb(skb);
 }
 
 static void hidp_recv_intr_frame(struct hidp_session *session,
@@ -845,6 +947,7 @@ static int hidp_setup_hid(struct hidp_session *session,
         hid->dev.parent = hidp_get_device(session);
         hid->ll_driver = &hidp_hid_driver;
 
+        hid->hid_get_raw_report = hidp_get_raw_report;
         hid->hid_output_raw_report = hidp_output_raw_report;
 
         return 0;
@@ -897,6 +1000,8 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
         skb_queue_head_init(&session->ctrl_transmit);
         skb_queue_head_init(&session->intr_transmit);
 
+        mutex_init(&session->report_mutex);
+        init_waitqueue_head(&session->report_queue);
         init_waitqueue_head(&session->startup_queue);
         session->waiting_for_startup = 1;
         session->flags   = req->flags & (1 << HIDP_BLUETOOTH_VENDOR_ID);
diff --git a/net/bluetooth/hidp/hidp.h b/net/bluetooth/hidp/hidp.h
index 92e093e61f27..13de5fa03480 100644
--- a/net/bluetooth/hidp/hidp.h
+++ b/net/bluetooth/hidp/hidp.h
@@ -80,6 +80,7 @@
 #define HIDP_VIRTUAL_CABLE_UNPLUG       0
 #define HIDP_BOOT_PROTOCOL_MODE         1
 #define HIDP_BLUETOOTH_VENDOR_ID        9
+#define HIDP_WAITING_FOR_RETURN         10
 #define HIDP_WAITING_FOR_SEND_ACK       11
 
 struct hidp_connadd_req {
@@ -155,6 +156,13 @@ struct hidp_session {
         struct sk_buff_head ctrl_transmit;
         struct sk_buff_head intr_transmit;
 
+        /* Used in hidp_get_raw_report() */
+        int waiting_report_type; /* HIDP_DATA_RTYPE_* */
+        int waiting_report_number; /* -1 for not numbered */
+        struct mutex report_mutex;
+        struct sk_buff *report_return;
+        wait_queue_head_t report_queue;
+
         /* Used in hidp_output_raw_report() */
         int output_report_success; /* boolean */