HID: bt: Move hid_add_device() call to after hidp_session() has started.

Move the call to hid_add_device() (which calls a device's probe() function)
to after the kernel_thread() call which starts the hidp_session() thread.
This ensures the Bluetooth receive socket is fully running by the time a
device's probe() function is called. This way, a device can communicate
(send and receive) with the Bluetooth device from its probe() function.

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 29544c21f4b52b33a34b87a8621d6150cd9b2455..67cc4bc82c6878d888307b3466c530b3dc6428d9 100644 (file)
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -563,6 +563,8 @@ static int hidp_session(void *arg)
        init_waitqueue_entry(&intr_wait, current);
        add_wait_queue(sk_sleep(ctrl_sk), &ctrl_wait);
        add_wait_queue(sk_sleep(intr_sk), &intr_wait);
+       session->waiting_for_startup = 0;
+       wake_up_interruptible(&session->startup_queue);
        while (!atomic_read(&session->terminate)) {
                set_current_state(TASK_INTERRUPTIBLE);
 
@@ -754,6 +756,8 @@ static struct hid_ll_driver hidp_hid_driver = {
        .hidinput_input_event = hidp_hidinput_event,
 };
 
+/* This function sets up the hid device. It does not add it
+   to the HID system. That is done in hidp_add_connection(). */
 static int hidp_setup_hid(struct hidp_session *session,
                                struct hidp_connadd_req *req)
 {
@@ -795,16 +799,8 @@ static int hidp_setup_hid(struct hidp_session *session,
 
        hid->hid_output_raw_report = hidp_output_raw_report;
 
-       err = hid_add_device(hid);
-       if (err < 0)
-               goto failed;
-
        return 0;
 
-failed:
-       hid_destroy_device(hid);
-       session->hid = NULL;
-
 fault:
        kfree(session->rd_data);
        session->rd_data = NULL;
@@ -853,6 +849,8 @@ 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);
 
+       init_waitqueue_head(&session->startup_queue);
+       session->waiting_for_startup = 1;
        session->flags   = req->flags & (1 << HIDP_BLUETOOTH_VENDOR_ID);
        session->idle_to = req->idle_to;
 
@@ -875,6 +873,14 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
        err = kernel_thread(hidp_session, session, CLONE_KERNEL);
        if (err < 0)
                goto unlink;
+       while (session->waiting_for_startup) {
+               wait_event_interruptible(session->startup_queue,
+                       !session->waiting_for_startup);
+       }
+
+       err = hid_add_device(session->hid);
+       if (err < 0)
+               goto err_add_device;
 
        if (session->input) {
                hidp_send_ctrl_message(session,
@@ -888,6 +894,12 @@ int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock,
        up_write(&hidp_session_sem);
        return 0;
 
+err_add_device:
+       hid_destroy_device(session->hid);
+       session->hid = NULL;
+       atomic_inc(&session->terminate);
+       hidp_schedule(session);
+
 unlink:
        hidp_del_timer(session);
 

diff --git a/net/bluetooth/hidp/hidp.h b/net/bluetooth/hidp/hidp.h
index 8d934a19da0a422c395ca93d400e53203a4c8627..2cc35dc8fa03c600e6d0fe6ac4320ab50a060436 100644 (file)
--- a/net/bluetooth/hidp/hidp.h
+++ b/net/bluetooth/hidp/hidp.h
@@ -157,6 +157,9 @@ struct hidp_session {
        /* Report descriptor */
        __u8 *rd_data;
        uint rd_size;
+
+       wait_queue_head_t startup_queue;
+       int waiting_for_startup;
 };
 
 static inline void hidp_schedule(struct hidp_session *session)