[PATCH v5 1/4] bt hidp: Move hid_add_device() call to after hidp_session() has started.

From: Alan Ott
Date: Tue Jan 18 2011 - 03:06:05 EST


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@xxxxxxxxxxx>
---
net/bluetooth/hidp/core.c | 28 ++++++++++++++++++++--------
net/bluetooth/hidp/hidp.h | 3 +++
2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 29544c2..67cc4bc 100644
--- 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 8d934a1..2cc35dc 100644
--- 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)
--
1.7.0.4


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/