This patch removes unnecessary braces in single statement blocks at the
same time as replaces the if statement with a ternary conditional.
Tested by compilation only.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds parens to sizeof operator uses.
Tested by compilation only.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a blank line after declarations.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch changes comments conforming coding style.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes an useless else branch after a break, reducing one
indent block.
Tested by compilation only.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes prohibited spaces before open parenthesis and open
brackets.
It also removes an assignment inside condition and unnecessary braces in
single statement block.
Tested by compilation only.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds spaces around operators.
Tested by compilation only.
Caught by checkpatch.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes useless initializations.
Tested by compilation only.
Caught by cppcheck.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch moves the constants to right.
Tested by compilation only.
Caught by coccinelle:
scripts/coccinelle/misc/compare_const_fl.cocci
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes an infinite 'for' loop and makes use of the already
existing 'restart' tag instead, reducing one leading tab.
The comments and code were corrected conforming file coding style.
Tested by compilation only.
Caught by checkpatch:
WARNING: Too many leading tabs - consider code refactoring
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch replaces the "exception" bitflag in the ehci_qh structure
with a more explicit "unlink_reason" bitmask. This is for use in the
following patch, where we will need to have a good idea of the
reason for unlinking a QH, not just "something exceptional happened".
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Michael Reutman <mreutman@epiqsolutions.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB stack uses error code -ENOSPC to indicate that the periodic
schedule is too full, with insufficient bandwidth to accommodate a new
allocation. It uses -EFBIG to indicate that an isochronous transfer
could not be linked into the schedule because it would exceed the
number of isochronous packets the host controller driver can handle
(generally because the new transfer would extend too far into the
future).
ehci-hcd uses the wrong error code at one point. This patch fixes it,
along with a misleading comment and debugging message.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit c3ee9b76aa (EHCI: improved logic for isochronous scheduling)
introduced the idea of using ehci->last_iso_frame as the origin (or
base) for the circular calculations involved in modifying the
isochronous schedule. However, the new code it added used
ehci->last_iso_frame before the value was properly initialized. This
patch rectifies the mistake by moving the initialization lines earlier
in iso_stream_schedule().
This fixes Bugzilla #72891.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: c3ee9b76aa
Reported-by: Joe Bryant <tenminjoe@yahoo.com>
Tested-by: Joe Bryant <tenminjoe@yahoo.com>
Tested-by: Martin Long <martin@longhome.co.uk>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes several sparse errors in ehci-hcd introduced by
commit 3d091a6f70 (USB: EHCI: AMD periodic frame list table quirk).
Although the problem fixed by that commit affects only little-endian
systems, the source code has to use types appropriate for big-endian
too.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes a type mismatch in ehci-hcd caused by commit
b35c5009bb (USB: EHCI: create per-TT bandwidth tables). The c_maskp
parameter in check_intr_schedule() was changed to point to unsigned
int rather than __hc32, but the prototype declaration wasn't adjusted
accordingly.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch changes the initial delay before the startup of a newly
scheduled isochronous stream. Currently the stream doesn't start
for at least 5 ms (40 microframes). This value is just an estimate;
it has no real justification.
Instead, we can start the stream as soon as possible after the
scheduling computations are complete. Essentially this requires
nothing more than reading the frame counter after the stream is
scheduled, instead of before.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch continues the scheduling changes in ehci-hcd by adding a
table to store the bandwidth allocation below each TT. This will
speed up the scheduling code, as it will no longer need to read
through the entire schedule to compute the bandwidth currently in use.
Properly speaking, the FS/LS budget calculations should be done in
terms of full-speed bytes per microframe, as described in the USB-2
spec. However the driver currently uses microseconds per microframe,
and the scheduling code isn't robust enough at this point to change
over. For the time being, we leave the calculations as they are.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch significantly changes the scheduling code in ehci-hcd.
Instead of calculating the current bandwidth utilization by trudging
through the schedule and adding up the times used by the existing
transfers, we will now maintain a table holding the time used for each
of 64 microframes. This will drastically speed up the bandwidth
computations.
In addition, it eliminates a theoretical bug. An isochronous endpoint
may have bandwidth reserved even at times when it has no transfers
listed in the schedule. The table will keep track of the reserved
bandwidth, whereas adding up entries in the schedule would miss it.
As a corollary, we can keep bandwidth reserved for endpoints even
when they aren't in active use. Eventually the bandwidth will be
reserved when a new alternate setting is installed; for now the
endpoint's reservation takes place when its first URB is submitted.
A drawback of this approach is that transfers with an interval larger
than 64 microframes will have to be charged for bandwidth as though
the interval was 64. In practice this shouldn't matter much;
transfers with longer intervals tend to be rather short anyway (things
like hubs or HID devices).
Another minor drawback is that we will keep track of two different
period and phase values: the actual ones and the ones used for
bandwidth allocation (which are limited to 64). This adds only a
small amount of overhead: 3 bytes for each endpoint.
The patch also adds a new debugfs file named "bandwidth" to display
the information stored in the new table.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch begins the process of unifying the scheduling parameters
that ehci-hcd uses for interrupt and isochronous transfers. It
creates an ehci_per_sched structure, which will be stored in both
ehci_qh and ehci_iso_stream structures, and will contain the common
scheduling information needed for both.
Initially we merely create the new structure and move some existing
fields into it. Later patches will add more fields and utilize these
structures in improved scheduling algorithms.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ehci-hcd is inconsistent in the sentinel values it uses to indicate
that no frame number has been assigned for a periodic transfer. Some
places it uses NO_FRAME (defined as 65535), other places it uses -1,
and elsewhere it uses 9999.
This patch defines a value for NO_FRAME which can fit in a 16-bit
signed integer, and changes the code to use it everywhere.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The scheduling code in ehci-hcd contains an error. For full-speed
isochronous-OUT transfers, the EHCI spec forbids scheduling
Start-Split transactions in H-microframe 7, but the driver allows it
anyway. This patch adds a check to prevent it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although the bandwidth statistics maintained by ehci-hcd show up only
in the /sys/kernel/debug/usb/devices file, they ought to be calculated
correctly. The calculation for full-speed isochronous endpoints is
wrong; it mistakenly yields bytes per microframe instead of bytes per
frame. The "interval" value, which is in frames, should not be
converted to microframes.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gustavo A. R. Silva
Felipe Balbi
Geyslan G. Bem
Alan Stern