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From: Joshua Henderson <joshua.henderson@microchip.com>
To: <linux-kernel@vger.kernel.org>
Cc: Cristian Birsan <cristian.birsan@microchip.com>,
	Joshua Henderson <joshua.henderson@microchip.com>,
	Felipe Balbi <balbi@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	<linux-usb@vger.kernel.org>
Subject: [PATCH v4 1/2] usb: musb: Fix DMA for host mode
Date: Fri, 19 Feb 2016 09:41:32 -0700	[thread overview]
Message-ID: <1455900093-15577-1-git-send-email-joshua.henderson@microchip.com> (raw)

From: Cristian Birsan <cristian.birsan@microchip.com>

Commit ac33cdb16681 ("usb: musb: Remove ifdefs for musb_host_rx in
musb_host.c part5") introduces a problem setting DMA host mode.

This commit fixes the done condition that advances the musb schedule.
Without this patch the the msub_advance_schedule() is called immediately
after receiving an endpoint RX interrupt without waiting for the DMA
transfer to complete. As a consequence when the dma complete interrupt
arrives the in_qh member of hw_ep is already null an the musb_host_rx()
exits on !urb error case.

Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Joshua Henderson <joshua.henderson@microchip.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
---
Changes since v3:
	- Fix formatting to 2 lines.
Changes since v2:
	- Put function call in if condition.
Changes since v1:
	- Don't add unecessary new variable. Just correct done.
---
 drivers/usb/musb/musb_host.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 795a45b..75c89b4 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -2003,10 +2003,8 @@ void musb_host_rx(struct musb *musb, u8 epnum)
 				qh->offset,
 				urb->transfer_buffer_length);
 
-			done = musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh,
-							      urb, xfer_len,
-							      iso_err);
-			if (done)
+			if (musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh, urb,
+							   xfer_len, iso_err))
 				goto finish;
 			else
 				dev_err(musb->controller, "error: rx_dma failed\n");
-- 
1.7.9.5

             reply	other threads:[~2016-02-19 16:41 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-19 16:41 Joshua Henderson [this message]
2016-02-19 17:54 ` [PATCH v4 1/2] usb: musb: Fix DMA for host mode Sergei Shtylyov

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