linux.git/drivers/usb/gadget/printer.c, branch master

usb: gadget: Gadget directory cleanup - group legacy gadgets

2014-07-16T17:14:05+00:00

The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the legacy gadgets (i.e. those not using configfs)
into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz 
Signed-off-by: Felipe Balbi

Merge tag 'usb-for-v3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

2014-03-08T00:47:36+00:00

Felipe writes:

usb: patches for v3.15

another substantial pull request with new features all over
the place.

dwc3 got a bit closer towards hibernation support with after
a few patches re-factoring code to be reused for hibernation.
Also in dwc3 two new workarounds for known silicon bugs have
been implemented, some randconfig build errors have been fixed,
and it was taught about the new generic phy layer.

MUSB on AM335x now supports isochronous transfers thanks to
George Cherian's work.

The atmel_usba driver got two crash fixes: one when no endpoint
was specified in DeviceTree data and another when stopping the UDC
in DEBUG builds.

Function FS got a much needed fix to ffs_epfile_io() which was
copying too much data to userspace in some cases.

The printer gadget got a fix for a possible deadlock and plugged
a memory leak.

Ethernet drivers now use NAPI for RX which gives improved throughput.

Other than that, the usual miscelaneous fixes, cleanups, and
the like.

Signed-of-by: Felipe Balbi

usb: gadget: printer: using gadget_is_otg to check otg support at runtime

2014-02-20T15:17:22+00:00

We need to use gadget_is_otg to check if the gadget is really
otg support at runtime, other composite gadget drivers have already
followed this method.

Signed-off-by: Peter Chen 
Signed-off-by: Felipe Balbi

usb: gadget: printer: fix memory leak

2014-02-18T16:52:54+00:00

When read data from g_printer, we see a Segmentation fault. eg:

Unable to handle kernel paging request at virtual address bf048000 pgd
= cf038000 [bf048000] *pgd=8e8cf811, *pte=00000000, *ppte=00000000
Internal error: Oops: 7 [#1] PREEMPT ARM Modules linked in: bluetooth
rfcomm g_printer
CPU: 0    Not tainted  (3.4.43-WR5.0.1.9_standard #1)
PC is at __copy_to_user_std+0x310/0x3a8 LR is at 0x4c808010
pc : []    lr : [<4c808010>]    psr: 20000013
sp : cf883ea8  ip : 80801018  fp : cf883f24
r10: bf04706c  r9 : 18a21205  r8 : 21953888
r7 : 201588aa  r6 : 5109aa16  r5 : 0705aaa2  r4 : 5140aa8a
r3 : 0000004c  r2 : 00000fdc  r1 : bf048000  r0 : bef5fc3c
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c5387d  Table: 8f038019  DAC: 00000015 Process
g_printer_test. (pid: 661, stack limit = 0xcf8822e8)
Stack: (0xcf883ea8 to 0xcf884000)
3ea0:                   bf047068 00001fff bef5ecb9 cf882000 00001fff bef5ecb9
3ec0: 00001fff 00000000 cf2e8724 bf044d3c 80000013 80000013 00000001
bf04706c
3ee0: cf883f24 cf883ef0 c012e5ac c0324388 c007c8ac c0046298 00008180
cf29b900
3f00: 00002000 bef5ecb8 cf883f68 00000003 cf882000 cf29b900 cf883f54
cf883f28
3f20: c012ea08 bf044b0c c000eb88 00000000 cf883f7c 00000000 00000000
00002000
3f40: bef5ecb8 00000003 cf883fa4 cf883f58 c012eae8 c012e960 00000001
bef60cb8
3f60: 000000a8 c000eb88 00000000 00000000 cf883fa4 00000000 c014329c
00000000
3f80: 000000d4 41af63f0 00000003 c000eb88 cf882000 00000000 00000000
cf883fa8
3fa0: c000e920 c012eaa4 00000000 000000d4 00000003 bef5ecb8 00002000
bef5ecb8
3fc0: 00000000 000000d4 41af63f0 00000003 b6f534c0 00000000 419f9000
00000000
3fe0: 00000000 bef5ecac 000086d9 41a986bc 60000010 00000003 0109608a
0088828a
Code: f5d1f07c e8b100f0 e1a03c2e e2522020 (e8b15300) ---[ end trace
97e2618e250e3377 ]--- Segmentation fault

The root cause is the dev->rx_buffers list has been broken.
When we call printer_read(), the following call tree is triggered:

printer_read()
	|
	+---setup_rx_reqs(req)
	|	|
	|	+---usb_ep_queue(req)
	|	|	|
	|	|	+---...
	|	|		|
	|	|		+---rx_complete(req).
	|	|
	|	+---add the req to dev->rx_reqs_active
	|
	+---while(!list_empty(&dev->rx_buffers)))

The route happens when we don't use DMA or fail to start DMA in USB
driver. We can see: in the case, in rx_complete() it will add the req
to dev->rx_buffers. meanwhile we see that we will also add the req to
dev->rx_reqs_active after usb_ep_queue() return, so this adding will
break the dev->rx_buffers out.

After, when we call list_empty() to check dev->rx_buffers in while(),
due to can't check correctly dev->rx_buffers, so the Segmentation fault
occurs when copy_to_user() is called.

Signed-off-by: wenlin.kang 
Signed-off-by: Felipe Balbi

usb: gadget: printer: fix possible deadlock

2014-02-18T16:52:54+00:00

The problem occurs in follow path.

printer_read()
	|
	+---setup_rx_reqs()
		|
		+---usb_ep_queue()
			|
			+---...
				|
				+---rx_complete()

Although it is clear from code, we can't get it normally.
only when we enable some spin_lock debug config option, we can find it.
eg:
BUG: spinlock lockup on CPU#0, g_printer_test_/584
 lock: bf05e158, .magic: dead4ead, .owner: g_printer_test_/584, .owner_cpu: 0
[] (unwind_backtrace+0x0/0x104) from [] (dump_stack+0x20/0x24)
[] (dump_stack+0x20/0x24) from [] (spin_dump+0x8c/0x94)
[] (spin_dump+0x8c/0x94) from [] (do_raw_spin_lock+0x128/0x154)
[] (do_raw_spin_lock+0x128/0x154) from [] (_raw_spin_lock_irqsave+0x64/0x70)
[] (_raw_spin_lock_irqsave+0x64/0x70) from [] (rx_complete+0x54/0x10c [g_printer])
[] (rx_complete+0x54/0x10c [g_printer]) from [] (musb_g_giveback+0x78/0x88)
[] (musb_g_giveback+0x78/0x88) from [] (rxstate+0xa0/0x10c)
[] (rxstate+0xa0/0x10c) from [] (musb_ep_restart+0x44/0x70)
[] (musb_ep_restart+0x44/0x70) from [] (musb_gadget_queue+0xe8/0xf8)
[] (musb_gadget_queue+0xe8/0xf8) from [] (setup_rx_reqs+0xa4/0x178 [g_printer])
[] (setup_rx_reqs+0xa4/0x178 [g_printer]) from [] (printer_read+0x9c/0x3f4 [g_printer])
[] (printer_read+0x9c/0x3f4 [g_printer]) from [] (vfs_read+0xb4/0x144)
[] (vfs_read+0xb4/0x144) from [] (sys_read+0x50/0x124)
[] (sys_read+0x50/0x124) from [] (ret_fast_syscall+0x0/0x3c)

The root cause is that we use the same lock two time in a path, so to avoid
the deadlock, we need to unlock in setup_rx_reqs(), and only unlock.

Signed-off-by: wenlin.kang 
Signed-off-by: Felipe Balbi

usb: gadget: fix error return code

2014-02-18T16:52:53+00:00

Set the return variable to an error code as done elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// 
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// 

Signed-off-by: Julia Lawall 
Signed-off-by: Felipe Balbi

new helper: file_inode(file)

2013-02-23T04:31:31+00:00

Signed-off-by: Al Viro

usb: gadget: always update HS/SS descriptors and create a copy of them

2012-10-31T13:09:44+00:00

HS and SS descriptors are staticaly created. They are updated during the
bind process with the endpoint address, string id or interface numbers.

After that, the descriptor chain is linked to struct usb_function which
is used by composite in order to serve the GET_DESCRIPTOR requests,
number of available configs and so on.

There is no need to assign the HS descriptor only if the UDC supports
HS speed because composite won't report those to the host if HS support
has not been reached. The same reasoning is valid for SS.

This patch makes sure each function updates HS/SS descriptors
unconditionally and uses the newly introduced helper function to create a
copy the descriptors for the speed which is supported by the UDC.

While at that, also rename f->descriptors to f->fs_descriptors in order
to make it more explicit what that means.

Cc: Laurent Pinchart 
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Felipe Balbi

usb: gadget: remove usb_gadget_controller_number()

2012-09-10T13:43:24+00:00

The bcdDevice field is defined as
|Device release number in binary-coded decimal
in the USB 2.0 specification. We use this field to distinguish the UDCs
from each other. In theory this could be used on the host side to apply
certain quirks if the "special" UDC in combination with this gadget is
used. This hasn't been done as far as I am aware. In practice it would
be better to fix the UDC driver before shipping since a later release
might not need this quirk anymore.

There are some driver in tree (on the host side) which use the bcdDevice
field to figure out special workarounds for a given firmware revision.
This seems to make sense. Therefore this patch converts all gadgets
(except a few) to use the kernel version instead a random 2 or 3 plus
the UDC number. The few that don't report kernel's version are:
- webcam
  This one reports always a version 0x10 so allow it to do so in future.
- nokia
  This one reports always 0x211. The comment says that this gadget works
  only if the UDC supports altsettings so I added a check for this.
- serial
  This one reports 0x2400 + UDC number. Since the gadget version is 2.4
  this could make sense. Therefore bcdDevice is 0x2400 here.

I also remove various gadget_is_ macros which are unused. The
remaining few macros should be moved to feature / bug bitfield.

Acked-by: Michal Nazarewicz 
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Felipe Balbi

usb: gadget: libcomposite: move composite.c into libcomposite

2012-09-10T13:13:03+00:00

This moves composite.c into libcomposite and updates all gadgets.
Finally!

Acked-by: Michal Nazarewicz 
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Felipe Balbi