[07/10] staging: most: usb: replace code to calculate array index

Message ID 1590570387-27069-8-git-send-email-christian.gromm@microchip.com
State New
Headers show
Series
  • [01/10] staging: most: usb: change order of function parameters
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Commit Message

Christian Gromm May 27, 2020, 9:06 a.m.
This patch removes the expression that makes use of a priori knowledge
about channel numbers to calculate an array index.
The expression 'peer = 1 - channel' utilizes the fact that an USB interface
that operates on the asynchronous data of the Network only has two
endpoints. Hence, channel being 0 or 1. The replacement is more simple and
less confusing when reading the code.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 drivers/staging/most/usb/usb.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

Patch

diff --git a/drivers/staging/most/usb/usb.c b/drivers/staging/most/usb/usb.c
index 03318de..468aabf 100644
--- a/drivers/staging/most/usb/usb.c
+++ b/drivers/staging/most/usb/usb.c
@@ -729,6 +729,8 @@  static void wq_clear_halt(struct work_struct *wq_obj)
 	struct most_dev *mdev = clear_work->mdev;
 	unsigned int channel = clear_work->channel;
 	int pipe = clear_work->pipe;
+	int snd_pipe;
+	int peer;
 
 	mutex_lock(&mdev->io_mutex);
 	most_stop_enqueue(&mdev->iface, channel);
@@ -746,9 +748,12 @@  static void wq_clear_halt(struct work_struct *wq_obj)
 	 */
 	if (mdev->conf[channel].data_type == MOST_CH_ASYNC &&
 	    mdev->conf[channel].direction == MOST_CH_RX) {
-		int peer = 1 - channel;
-		int snd_pipe = usb_sndbulkpipe(mdev->usb_device,
-					       mdev->ep_address[peer]);
+		if (channel == 0)
+			peer = 1;
+		else
+			peer = 0;
+		snd_pipe = usb_sndbulkpipe(mdev->usb_device,
+					   mdev->ep_address[peer]);
 		usb_clear_halt(mdev->usb_device, snd_pipe);
 	}
 	mdev->is_channel_healthy[channel] = true;