[PATCH] staging: dwc2: Make dwc2_hw_params.host_channels large enough

Matthijs Kooijman matthijs at stdin.nl
Tue Oct 1 21:42:52 UTC 2013

The hardware offers a 4-bit register containing the number of host
channels. However, the values of these register mean 1-16 host channels,
not 0-15. Since the dwc2_hw_params struct stores the actual number of
host channels supported instead of the raw register value, it should be
5 bits wide instead of 4.

Before this commit, hardware with 16 host channels would overflow the
field, making it appear as 0 channels.

This bug was introduced in commit 9badec2 (staging: dwc2: interpret all
hwcfg and related register at init time).

Reported-by: Dinh Nguyen <dinh.linux at gmail.com>
Signed-off-by: Matthijs Kooijman <matthijs at stdin.nl>
 drivers/staging/dwc2/core.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/dwc2/core.h b/drivers/staging/dwc2/core.h
index f7ba34b..fab718d 100644
--- a/drivers/staging/dwc2/core.h
+++ b/drivers/staging/dwc2/core.h
@@ -294,7 +294,7 @@ struct dwc2_hw_params {
 	unsigned dev_token_q_depth:5;
 	unsigned max_transfer_size:26;
 	unsigned max_packet_count:11;
-	unsigned host_channels:4;
+	unsigned host_channels:5;
 	unsigned hs_phy_type:2;
 	unsigned fs_phy_type:2;
 	unsigned i2c_enable:1;

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