Commit 6d71ba21 authored by Pavan Savoy's avatar Pavan Savoy Committed by Greg Kroah-Hartman
Browse files

drivers:misc: ti-st: fix hci-ll on wake_ind collision 



Where file-transfer stops/pauses in between, is
result of a HCI-LL anamoly in ST LL driver.
ST LL did not copy the contents of WaitQ into the TxQ, when a WAKEUP_IND
collision happened.
Make also sure, that the copying mechanism is safe, by wrapping it around
spin locks inside st_int_recv().
This was easily reproduced when the sleep timeout was reduced to 100ms
for HCI-LL.

Signed-off-by: default avatarPavan Savoy <pavan_savoy@ti.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent ef04d121

drivers/misc/ti-st/st_core.c

+15 −0
Original line number Diff line number Diff line
@@ -236,6 +236,7 @@ void st_int_recv(void *disc_data, 
	int len = 0, type = 0;

	unsigned char *plen;

	struct st_data_s *st_gdata = (struct st_data_s *)disc_data;

	unsigned long flags;



	ptr = (char *)data;

	/* tty_receive sent null ? */
@@ -248,6 +249,7 @@ void st_int_recv(void *disc_data, 
		   "rx_count %ld", count, st_gdata->rx_state,

		   st_gdata->rx_count);



	spin_lock_irqsave(&st_gdata->lock, flags);

	/* Decode received bytes here */

	while (count) {

		if (st_gdata->rx_count) {
@@ -308,13 +310,25 @@ void st_int_recv(void *disc_data, 
			 * sleep state received --

			 */

			st_ll_sleep_state(st_gdata, *ptr);

			/* if WAKEUP_IND collides copy from waitq to txq

			 * and assume chip awake

			 */

			spin_unlock_irqrestore(&st_gdata->lock, flags);

			if (st_ll_getstate(st_gdata) == ST_LL_AWAKE)

				st_wakeup_ack(st_gdata, LL_WAKE_UP_ACK);

			spin_lock_irqsave(&st_gdata->lock, flags);



			ptr++;

			count--;

			continue;

		case LL_WAKE_UP_ACK:

			pr_debug("PM packet");



			spin_unlock_irqrestore(&st_gdata->lock, flags);

			/* wake up ack received */

			st_wakeup_ack(st_gdata, *ptr);

			spin_lock_irqsave(&st_gdata->lock, flags);



			ptr++;

			count--;

			continue;
@@ -337,6 +351,7 @@ void st_int_recv(void *disc_data, 
		ptr++;

		count--;

	}

	spin_unlock_irqrestore(&st_gdata->lock, flags);

	pr_debug("done %s", __func__);

	return;

}

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