48 lines
1.5 KiB
Diff
48 lines
1.5 KiB
Diff
|
From: Mark Brown <broonie@kernel.org>
|
||
|
|
Date: Tue, 9 Dec 2014 19:46:56 +0000
|
||
|
|
Subject: [PATCH] spi: Check to see if the device is processing a message
|
||
|
|
before we idle
|
||
|
|
|
||
|
|
cur_msg is updated under the queue lock and holds the message we are
|
||
|
|
currently processing. Since currently we only ever do removals in the
|
||
|
|
pump kthread it doesn't matter in what order we do things but we want
|
||
|
|
to be able to push things out from the submitting thread so pull the
|
||
|
|
check to see if we're currently handling a message before we check to
|
||
|
|
see if the queue is idle.
|
||
|
|
|
||
|
|
Signed-off-by: Mark Brown <broonie@kernel.org>
|
||
|
|
---
|
||
|
|
|
||
|
|
--- a/drivers/spi/spi.c
|
||
|
|
+++ b/drivers/spi/spi.c
|
||
|
|
@@ -891,8 +891,16 @@ static void spi_pump_messages(struct kth
|
||
|
|
bool was_busy = false;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
- /* Lock queue and check for queue work */
|
||
|
|
+ /* Lock queue */
|
||
|
|
spin_lock_irqsave(&master->queue_lock, flags);
|
||
|
|
+
|
||
|
|
+ /* Make sure we are not already running a message */
|
||
|
|
+ if (master->cur_msg) {
|
||
|
|
+ spin_unlock_irqrestore(&master->queue_lock, flags);
|
||
|
|
+ return;
|
||
|
|
+ }
|
||
|
|
+
|
||
|
|
+ /* Check if the queue is idle */
|
||
|
|
if (list_empty(&master->queue) || !master->running) {
|
||
|
|
if (!master->busy) {
|
||
|
|
spin_unlock_irqrestore(&master->queue_lock, flags);
|
||
|
|
@@ -916,11 +924,6 @@ static void spi_pump_messages(struct kth
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
- /* Make sure we are not already running a message */
|
||
|
|
- if (master->cur_msg) {
|
||
|
|
- spin_unlock_irqrestore(&master->queue_lock, flags);
|
||
|
|
- return;
|
||
|
|
- }
|
||
|
|
/* Extract head of queue */
|
||
|
|
master->cur_msg =
|
||
|
|
list_first_entry(&master->queue, struct spi_message, queue);
|