From: Linus Walleij <linus.walleij@linaro.org>
Date: Tue, 11 Aug 2015 09:56:40 +0000 (+0200)
Subject: iio: percolate error if event fd fails
X-Git-Url: http://git.efficios.com/?a=commitdiff_plain;h=3f9059b71791cf0e57a4879594f0066237976943;p=deliverable%2Flinux.git

iio: percolate error if event fd fails

This makes the error from iio_event_getfd() percolate up
to userspace properly so we can know for sure there is no
events on this device (-ENODEV returned). Before this patch
we would bail out looking for the unsupported events on the
erroneous (negative) file descriptor.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index b3fcc2c449d8..b347524d1b6d 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1153,6 +1153,8 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 	if (cmd == IIO_GET_EVENT_FD_IOCTL) {
 		fd = iio_event_getfd(indio_dev);
+		if (fd < 0)
+			return fd;
 		if (copy_to_user(ip, &fd, sizeof(fd)))
 			return -EFAULT;
 		return 0;