kernel: split patches folder up into backport, pending and hack folders

[openwrt/openwrt.git] / target / linux / generic / pending-3.18 / 092-01-spi-Check-to-see-if-the-device-is-processing-a-messa.patch

diff --git a/target/linux/generic/pending-3.18/092-01-spi-Check-to-see-if-the-device-is-processing-a-messa.patch b/target/linux/generic/pending-3.18/092-01-spi-Check-to-see-if-the-device-is-processing-a-messa.patch
new file mode 100644 (file)
index 0000000..fa3ab6a
--- /dev/null
+++ b/target/linux/generic/pending-3.18/092-01-spi-Check-to-see-if-the-device-is-processing-a-messa.patch
@@ -0,0 +1,47 @@
+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);