HID: bt: Wait for ACK on Sent Reports

Wait for an ACK from the device before returning from
hidp_output_raw_report(). This way, failures can be returned to the user
application. Also, it prevents ACK/NAK packets from an output packet from
being confused with ACK/NAK packets from an input request packet.

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

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 67cc4bc..5383e6c 100644 (file)
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -316,6 +316,9 @@ static int hidp_send_report(struct hidp_session *session, struct hid_report *rep
 static int hidp_output_raw_report(struct hid_device *hid, unsigned char *data, size_t count,
                unsigned char report_type)
 {
+       struct hidp_session *session = hid->driver_data;
+       int ret;
+
        switch (report_type) {
        case HID_FEATURE_REPORT:
                report_type = HIDP_TRANS_SET_REPORT | HIDP_DATA_RTYPE_FEATURE;
@@ -327,10 +330,47 @@ static int hidp_output_raw_report(struct hid_device *hid, unsigned char *data, s
                return -EINVAL;
        }
 
+       if (mutex_lock_interruptible(&session->report_mutex))
+               return -ERESTARTSYS;
+
+       /* Set up our wait, and send the report request to the device. */
+       set_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags);
        if (hidp_send_ctrl_message(hid->driver_data, report_type,
-                       data, count))
-               return -ENOMEM;
-       return count;
+                       data, count)) {
+               ret = -ENOMEM;
+               goto err;
+       }
+
+       /* Wait for the ACK from the device. */
+       while (test_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags)) {
+               int res;
+
+               res = wait_event_interruptible_timeout(session->report_queue,
+                       !test_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags),
+                       10*HZ);
+               if (res == 0) {
+                       /* timeout */
+                       ret = -EIO;
+                       goto err;
+               }
+               if (res < 0) {
+                       /* signal */
+                       ret = -ERESTARTSYS;
+                       goto err;
+               }
+       }
+
+       if (!session->output_report_success) {
+               ret = -EIO;
+               goto err;
+       }
+
+       ret = count;
+
+err:
+       clear_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags);
+       mutex_unlock(&session->report_mutex);
+       return ret;
 }
 
 static void hidp_idle_timeout(unsigned long arg)
@@ -357,10 +397,12 @@ static void hidp_process_handshake(struct hidp_session *session,
                                        unsigned char param)
 {
        BT_DBG("session %p param 0x%02x", session, param);
+       session->output_report_success = 0; /* default condition */
 
        switch (param) {
        case HIDP_HSHK_SUCCESSFUL:
                /* FIXME: Call into SET_ GET_ handlers here */
+               session->output_report_success = 1;
                break;
 
        case HIDP_HSHK_NOT_READY:
@@ -385,6 +427,12 @@ static void hidp_process_handshake(struct hidp_session *session,
                        HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
                break;
        }
+
+       /* Wake up the waiting thread. */
+       if (test_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags)) {
+               clear_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags);
+               wake_up_interruptible(&session->report_queue);
+       }
 }
 
 static void hidp_process_hid_control(struct hidp_session *session,

diff --git a/net/bluetooth/hidp/hidp.h b/net/bluetooth/hidp/hidp.h
index 2cc35dc..92e093e 100644 (file)
--- 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_SEND_ACK      11
 
 struct hidp_connadd_req {
        int   ctrl_sock;        // Connected control socket
@@ -154,6 +155,9 @@ struct hidp_session {
        struct sk_buff_head ctrl_transmit;
        struct sk_buff_head intr_transmit;
 
+       /* Used in hidp_output_raw_report() */
+       int output_report_success; /* boolean */
+
        /* Report descriptor */
        __u8 *rd_data;
        uint rd_size;