openwrtv4/target/linux/generic/pending-3.18/092-01-spi-Check-to-see-if-the-device-is-processing-a-messa.patch
John Crispin 74d00a8c38 kernel: split patches folder up into backport, pending and hack folders
* properly format/comment all patches
* merge debloat patches
* merge Kconfig patches
* merge swconfig patches
* merge hotplug patches
* drop 200-fix_localversion.patch - upstream
* drop 222-arm_zimage_none.patch - unused
* drop 252-mv_cesa_depends.patch - no longer required
* drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused
* drop 661-fq_codel_keep_dropped_stats.patch - outdated
* drop 702-phy_add_aneg_done_function.patch - upstream
* drop 840-rtc7301.patch - unused
* drop 841-rtc_pt7c4338.patch - upstream
* drop 921-use_preinit_as_init.patch - unused
* drop spio-gpio-old and gpio-mmc - unused

Signed-off-by: John Crispin <john@phrozen.org>
2017-08-05 08:46:36 +02:00

47 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);