* patch "usb: gadget: composite: Test get_alt() presence instead of set_alt()" added to usb-linus
@ 2017-01-03 13:41 gregkh
0 siblings, 0 replies; only message in thread
From: gregkh @ 2017-01-03 13:41 UTC (permalink / raw)
To: k.opasiak, felipe.balbi, stable
This is a note to let you know that I've just added the patch titled
usb: gadget: composite: Test get_alt() presence instead of set_alt()
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 7e4da3fcf7c9fe042f2f7cb7bf23861a899b4a8f Mon Sep 17 00:00:00 2001
From: Krzysztof Opasiak <k.opasiak@samsung.com>
Date: Tue, 20 Dec 2016 19:52:16 +0100
Subject: usb: gadget: composite: Test get_alt() presence instead of set_alt()
By convention (according to doc) if function does not provide
get_alt() callback composite framework should assume that it has only
altsetting 0 and should respond with error if host tries to set
other one.
After commit dd4dff8b035f ("USB: composite: Fix bug: should test
set_alt function pointer before use it")
we started checking set_alt() callback instead of get_alt().
This check is useless as we check if set_alt() is set inside
usb_add_function() and fail if it's NULL.
Let's fix this check and move comment about why we check the get
method instead of set a little bit closer to prevent future false
fixes.
Fixes: dd4dff8b035f ("USB: composite: Fix bug: should test set_alt function pointer before use it")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
---
drivers/usb/gadget/composite.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 41ab61f9b6e0..002822d98fda 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1694,9 +1694,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
value = min(w_length, (u16) 1);
break;
- /* function drivers must handle get/set altsetting; if there's
- * no get() method, we know only altsetting zero works.
- */
+ /* function drivers must handle get/set altsetting */
case USB_REQ_SET_INTERFACE:
if (ctrl->bRequestType != USB_RECIP_INTERFACE)
goto unknown;
@@ -1705,7 +1703,13 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
f = cdev->config->interface[intf];
if (!f)
break;
- if (w_value && !f->set_alt)
+
+ /*
+ * If there's no get_alt() method, we know only altsetting zero
+ * works. There is no need to check if set_alt() is not NULL
+ * as we check this in usb_add_function().
+ */
+ if (w_value && !f->get_alt)
break;
value = f->set_alt(f, w_index, w_value);
if (value == USB_GADGET_DELAYED_STATUS) {
--
2.11.0
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2017-01-03 13:41 patch "usb: gadget: composite: Test get_alt() presence instead of set_alt()" added to usb-linus gregkh
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