[PATCH 2/2] Misc, phantom, fix poll

[Jiri Slaby]

Return ERR even if there are pending data, but hw is not running. Do not
decrement count in poll, do it in ioctl, where data are actually read.

Signed-off-by: Jiri Slaby <jirislaby@xxxxxxxxx>
---
 drivers/misc/phantom.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/phantom.c b/drivers/misc/phantom.c
index 5447a60..71d1c84 100644
--- a/drivers/misc/phantom.c
+++ b/drivers/misc/phantom.c
@@ -169,6 +169,7 @@ static long phantom_ioctl(struct file *file, unsigned int cmd,
 		for (i = 0; i < m; i++)
 			if (rs.mask & BIT(i))
 				rs.values[i] = ioread32(dev->iaddr + i);
+		atomic_set(&dev->counter, 0);
 		spin_unlock_irqrestore(&dev->regs_lock, flags);
 
 		if (copy_to_user(argp, &rs, sizeof(rs)))
@@ -254,11 +255,12 @@ static unsigned int phantom_poll(struct file *file, poll_table *wait)
 
 	pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
 	poll_wait(file, &dev->wait, wait);
-	if (atomic_read(&dev->counter)) {
+
+	if (!(dev->status & PHB_RUNNING))
+		mask = POLLERR;
+	else if (atomic_read(&dev->counter))
 		mask = POLLIN | POLLRDNORM;
-		atomic_dec(&dev->counter);
-	} else if ((dev->status & PHB_RUNNING) == 0)
-		mask = POLLIN | POLLRDNORM | POLLERR;
+
 	pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
 
 	return mask;
-- 
1.5.4.1

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