V4L/DVB (11617): cx18: Set up to wait for a one-shot response before sending a firmware cmd
When sending an outgoing firmware command, prepare to wait before we raise the
interrupt, so we don't miss the wake_up() on the acknowledgment. When waiting
for the acknowledgement, there is no need to loop around schedule(), as there
will only be one interrupt, and hence one wake_up(), issued.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/cx18/cx18-mailbox.c b/drivers/media/video/cx18/cx18-mailbox.c
index 2a4d435..df7d61d 100644
--- a/drivers/media/video/cx18/cx18-mailbox.c
+++ b/drivers/media/video/cx18/cx18-mailbox.c
@@ -478,9 +478,10 @@
u32 __iomem *xpu_state;
wait_queue_head_t *waitq;
struct mutex *mb_lock;
- long int timeout, ret;
+ unsigned long int t0, timeout, ret;
int i;
char argstr[MAX_MB_ARGUMENTS*11+1];
+ DEFINE_WAIT(w);
if (info == NULL) {
CX18_WARN("unknown cmd %x\n", cmd);
@@ -562,25 +563,49 @@
CX18_DEBUG_HI_IRQ("sending interrupt SW1: %x to send %s\n",
irq, info->name);
+
+ /* So we don't miss the wakeup, prepare to wait before notifying fw */
+ prepare_to_wait(waitq, &w, TASK_UNINTERRUPTIBLE);
cx18_write_reg_expect(cx, irq, SW1_INT_SET, irq, irq);
- ret = wait_event_timeout(
- *waitq,
- cx18_readl(cx, &mb->ack) == cx18_readl(cx, &mb->request),
- timeout);
+ t0 = jiffies;
+ ack = cx18_readl(cx, &mb->ack);
+ if (ack != req) {
+ schedule_timeout(timeout);
+ ret = jiffies - t0;
+ ack = cx18_readl(cx, &mb->ack);
+ } else {
+ ret = jiffies - t0;
+ }
- if (ret == 0) {
- /* Timed out */
+ finish_wait(waitq, &w);
+
+ if (req != ack) {
mutex_unlock(mb_lock);
- CX18_DEBUG_WARN("sending %s timed out waiting %d msecs for RPU "
- "acknowledgement\n",
- info->name, jiffies_to_msecs(timeout));
+ if (ret >= timeout) {
+ /* Timed out */
+ CX18_DEBUG_WARN("sending %s timed out waiting %d msecs "
+ "for RPU acknowledgement\n",
+ info->name, jiffies_to_msecs(ret));
+ } else {
+ CX18_DEBUG_WARN("woken up before mailbox ack was ready "
+ "after submitting %s to RPU. only "
+ "waited %d msecs on req %u but awakened"
+ " with unmatched ack %u\n",
+ info->name,
+ jiffies_to_msecs(ret),
+ req, ack);
+ }
return -EINVAL;
}
- if (ret != timeout)
+ if (ret >= timeout)
+ CX18_DEBUG_WARN("failed to be awakened upon RPU acknowledgment "
+ "sending %s; timed out waiting %d msecs\n",
+ info->name, jiffies_to_msecs(ret));
+ else
CX18_DEBUG_HI_API("waited %u msecs for %s to be acked\n",
- jiffies_to_msecs(timeout-ret), info->name);
+ jiffies_to_msecs(ret), info->name);
/* Collect data returned by the XPU */
for (i = 0; i < MAX_MB_ARGUMENTS; i++)