Impact: restructure the VFS layout of per CPU trace buffers

The per cpu trace files are all in a single directory:
/debug/tracing/per_cpu. In case of a large number of cpu, the
content of this directory becomes messy so we create now one
directory per cpu inside /debug/tracing/per_cpu which contain
each their own trace_pipe and trace files.

Ie:

 /debug/tracing$ ls -R per_cpu
 per_cpu:
 cpu0  cpu1

 per_cpu/cpu0:
 trace  trace_pipe

 per_cpu/cpu1:
 trace  trace_pipe
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge branch 'tip/tracing/ftrace' of ssh://master.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace

Peter Zijlstra warned that TPPROTO and TPARGS might become something
other than a simple copy of itself. To prevent this from having
side effects in the TRACE_FORMAT macro in tracepoint.h, we add a
PARAMS() macro to be defined as just a wrapper.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

There's been a bit confusion to whether DEFINE/DECLARE_TRACE_FMT should
be a DEFINE or a DECLARE. Ingo Molnar suggested simply calling it
TRACE_FORMAT.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

Now that several per-cpu files can be read or spliced at the
same, we want the read/splice callbacks for tracing files to be
reentrants.

Until now, a single global mutex (trace_types_lock) serialized
the access to tracing_read_pipe(), tracing_splice_read_pipe(),
and the seq helpers.

Ie: it means that if a user tries to read trace_pipe0 and
trace_pipe1 at the same time, the access to the function
tracing_read_pipe() is contended and one reader must wait for
the other to finish its read call.

The trace_type_lock mutex is mostly here to serialize the access
to the global current tracer (current_trace), which can be
changed concurrently. Although the iter struct keeps a private
pointer to this tracer, its callbacks can be changed by another
function.

The method used here is to not keep anymore private reference to
the tracer inside the iterator but to make a copy of it inside
the iterator. Then it checks on subsequents read calls if the
tracer has changed. This is not costly because the current
tracer is not expected to be changed often, so we use a branch
prediction for that.

Moreover, we add a private mutex to the iterator (there is one
iterator per file descriptor) to serialize the accesses in case
of multiple consumers per file descriptor (which would be a
silly idea from the user). Note that this is not to protect the
ring buffer, since the ring buffer already serializes the
readers accesses. This is to prevent from traces weirdness in
case of concurrent consumers. But these mutexes can be dropped
anyway, that would not result in any crash. Just tell me what
you think about it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: split up tracing output per cpu

Currently, on the tracing debugfs directory, three files are
available to the user to let him extracting the trace output:

- trace is an iterator through the ring-buffer. It's a reader
  but not a consumer It doesn't block when no more traces are
  available.

- trace pretty similar to the former, except that it adds more
  informations such as prempt count, irq flag, ...

- trace_pipe is a reader and a consumer, it will also block
  waiting for traces if necessary (heh, yes it's a pipe).

The traces coming from different cpus are curretly mixed up
inside these files. Sometimes it messes up the informations,
sometimes it's useful, depending on what does the tracer
capture.

The tracing_cpumask file is useful to filter the output and
select only the traces captured a custom defined set of cpus.
But still it is not enough powerful to extract at the same time
one trace buffer per cpu.

So this patch creates a new directory: /debug/tracing/per_cpu/.

Inside this directory, you will now find one trace_pipe file and
one trace file per cpu.

Which means if you have two cpus, you will have:

 trace0
 trace1
 trace_pipe0
 trace_pipe1

And of course, reading these files will have the same effect
than with the usual tracing files, except that you will only see
the traces from the given cpu.

The original all-in-one cpu trace file are still available on
their original place.

Until now, only one consumer was allowed on trace_pipe to avoid
racy consuming on the ring-buffer. Now the approach changed a
bit, you can have only one consumer per cpu.

Which means you are allowed to read concurrently trace_pipe0 and
trace_pipe1 But you can't have two readers on trace_pipe0 or
trace_pipe1.

Following the same logic, if there is one reader on the common
trace_pipe, you can not have at the same time another reader on
trace_pipe0 or in trace_pipe1. Because in trace_pipe is already
a consumer in all cpu buffers in essence.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge branch 'tip/tracing/ftrace' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace

Impact: remove old debug/tracing API

/debug/tracing/latency_trace is an old legacy format we kept from
the old latency tracer. Remove the file for now. If there's any
useful bit missing then we'll propagate any useful output bits into
the /debug/tracing/trace output.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: fix CPU hotplug lockup

bts_hotcpu_handler() is called with irqs disabled, so using mutex_lock()
is a no-no.

All the BTS codepaths here are atomic (they do not schedule), so using
a spinlock is the right solution.

Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

This patch adds the directory /debug/tracing/events/ that will contain
all the registered trace points.

 # ls /debug/tracing/events/
sched_kthread_stop      sched_process_fork  sched_switch
sched_kthread_stop_ret  sched_process_free  sched_wait_task
sched_migrate_task      sched_process_wait  sched_wakeup
sched_process_exit      sched_signal_send   sched_wakeup_new

 # ls /debug/tracing/events/sched_switch/
enable

 # cat /debug/tracing/events/sched_switch/enable
1

 # cat /debug/tracing/set_event
sched_switch
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

This patch changes the trace/sched.h to use the DECLARE_TRACE_FMT
such that they are automatically registered with the event tracer.

And it also adds the tracing sched headers to kernel/trace/events.c
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

This patch creates the event tracing infrastructure of ftrace.
It will create the files:

 /debug/tracing/available_events
 /debug/tracing/set_event

The available_events will list the trace points that have been
registered with the event tracer.

set_events will allow the user to enable or disable an event hook.

example:

 # echo sched_wakeup > /debug/tracing/set_event

Will enable the sched_wakeup event (if it is registered).

 # echo "!sched_wakeup" >> /debug/tracing/set_event

Will disable the sched_wakeup event (and only that event).

 # echo > /debug/tracing/set_event

Will disable all events (notice the '>')

 # cat /debug/tracing/available_events > /debug/tracing/set_event

Will enable all registered event hooks.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

This patch creates a DEFINE_TRACE_FMT to map to DECLARE_TRACE.
This allows for the developers to place format strings and
args in with their tracepoint declaration. A tracer may now
override the DEFINE_TRACE_FMT macro and use it to record
a default format.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>

* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
  proc: fix PG_locked reporting in /proc/kpageflags

* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  Add i2c_board_info for RiscPC PCF8583
  i2c: Make sure i2c_algo_bit_data.timeout is HZ-independent
  i2c-dev: Clarify the unit of ioctl I2C_TIMEOUT
  i2c: Timeouts reach -1
  i2c: Fix misplaced parentheses

Merge branch 'firedtv-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6

* 'firedtv-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firedtv: dvb_frontend_info for FireDTV S2, fix "frequency limits undefined" error
  firedtv: massive refactoring
  firedtv: rename files, variables, functions from firesat to firedtv
  firedtv: Use DEFINE_SPINLOCK
  firedtv: fix registration - adapter number could only be zero
  firedtv: use length_field() of PMT as length
  firedtv: fix returned struct for ca_info
  firedtv: cleanups and minor fixes
  ieee1394: remove superfluous assertions
  ieee1394: inherit ud vendor_id from node vendor_id
  ieee1394: add hpsb_node_read() and hpsb_node_lock()
  ieee1394: use correct barrier types between accesses of nodeid and generation
  firesat: copyrights, rename to firedtv, API conversions, fix remote control input
  firesat: avc resend
  firesat: update isochronous interface, add CI support
  firesat: add DVB-S support for DVB-S2 devices
  firesat: fix DVB-S2 device recognition
  DVB: add firesat driver

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Fix deadlock in ext4_write_begin() and ext4_da_write_begin()
  ext4: Add fallback for find_group_flex

Add the necessary i2c_board_info structure to fix the lack of PCF8583
RTC on RiscPC.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>

i2c_algo_bit_data.timeout is supposed to be in jiffies, so drivers
should use set this value in terms of HZ.

Ultimately I think this field should be discarded in favor of
i2c_adapter.timeout, but that's left for a future patch.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Lennert Buytenhek <kernel@wantstofly.org>
Acked-by: Len Sorensen <lsorense@csclub.uwaterloo.ca>

The unit in which user-space can set the bus timeout value is jiffies
for historical reasons (back when HZ was always 100.) This is however
not good because user-space doesn't know how long a jiffy lasts. The
timeout value should instead be set in a fixed time unit. Given the
original value of HZ, this unit should be 10 ms, for compatibility.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>

With a postfix decrement these timeouts reach -1 rather than 0, but
after the loop it is tested whether they have become 0.

As pointed out by Jean Delvare, the condition we are waiting for should
also be tested before the timeout. With the current order, you could
exit with a timeout error while the job is actually done.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Fix misplaced parentheses.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Expr always evaluates to zero.

Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

Remove unnecessary CONFIG guards around type declarations and macro
definitions.
Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: markus.t.metzger@gmail.com
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Fix an invalid memory reference problem when cpu hotplug support is
disabled and the hw-branch-tracer is set as current tracer.

Initializing the tracer calls bts_trace_init() which has already
been freed at this time.
Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

I found that the function fdtv_frontend_init in the file firedtv-fe.c was
missing a case for FIREDTV_DVB_S2 which resulted in "frequency limits
undefined" errors in syslog.
Signed-off-by: Beat Michel Liechti <bml303@gmail.com>

Change by Stefan R: combine it with case case FIREDTV_DVB_S as
originally suggested by Beat Michel.  This enables FE_CAN_FEC_AUTO also
for FireDTV-S2 devices which is possible as long as only DVB-S channels
are used.  FE_CAN_FEC_AUTO would be wrong for DVB-S2 channels, but those
cannot be used yet since the driver is not yet converted to S2API.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Combination of the following changes:

Mon, 23 Feb 2009 14:21:10 +0100 (CET)
firedtv: reinstate debug logging option

    Henrik Kurelid tells me that FCP debug logging (which I removed during
    cleanups) is still useful when working on driver issues together with
    end users.  So bring it back in an updated form with only 60% of the
    original code footprint.

    Logging can be enabled with
    # echo -1 > /sys/module/firedtv/parameters/debug

    1 instead of -1 enables only FCP header logging,
    2 instead of -1 enables only hexdumps of the entire FCP frames.
    0 switches logging off again.

Fri, 20 Feb 2009 20:54:27 +0100 (CET)
firedtv: build fix for INPUT=m and DVB_FIREDTV=y

Thu, 19 Feb 2009 20:40:39 +0100
firedtv: use msecs_to_jiffies

    Pointed out by Mauro Carvalho Chehab.

Sun Feb 15 20:50:46 CET 2009
firedtv: some more housekeeping

    Fix an old checkpatch warning and a new compiler warning.

Sun Feb 15 15:33:17 CET 2009
firedtv: rename a file once more

    At the moment, about a third of avc.c is specific to FireDTVs rather
    than generic AV/C code.  Rename it to firedtv-avc.c.

Sun Feb 15 15:33:17 CET 2009
firedtv: dvb demux: more compact channels backing store

    Replace struct firedtv_channel { bool active; int pid; } channel[16];
    by unsigned long channel_active; u16 channel_pid[16];.

Sun Feb 15 15:33:17 CET 2009
firedtv: dvb demux: some simplifications

    c->active was unnecessarily cleared twice.

    Also, by marking the channel inactive before the for loop,
    the loop becomes identical with fdtv_channel_collect().

Sun Feb 15 15:33:17 CET 2009
firedtv: dvb demux: remove a bogus loop

    This loop is unnecessary because
      - only active channel[].pid's will be sent to the device,
      - when a channel is activated, its pid is set to dvbdmxfeed->pid.

    Perhaps the original code was there because it was initially not fully
    covered by the fdtv->demux_mutex.

Sun Feb 15 15:33:17 CET 2009
firedtv: dvb demux: fix mutex protection

    fdtv_start_feed() accessed the channel list unsafely.
    Fully serialize it with itself and fdtv_stop_feed().

Sun Feb 15 15:33:17 CET 2009
firedtv: dvb demux: fix missing braces

    Original code was:
            ...
            case DMX_TS_PES_OTHER:
                    //Dirty fix to keep firesat->channel pid-list up to date
                    for(k=0;k<16;k++){
                            if(firesat->channel[k].active == 0)
                                    firesat->channel[k].pid =
                                            dvbdmxfeed->pid;
                                    break;
                    }
                    channel = firesat_channel_allocate(firesat);
                    break;
            default:
            ...

    Looks bogus in several respects. For now let's just add braces to the if
    because that seems to be what the author meant.

Sun Feb 15 15:33:17 CET 2009
firedtv: allow build without input subsystem

    !CONFIG_INPUT is very unlikely on systems on which firedtv is of
    interest.  But we can easily support it.

Sun Feb 15 15:33:17 CET 2009
firedtv: replace EXTRA_CFLAGS by ccflags

    The former are deprecated.
    The latter can depend on Kconfig variables.

Sun Feb 15 15:33:17 CET 2009
firedtv: concentrate ieee1394 dependencies

    Move the entire interface with drivers/ieee1394 to firedtv-1394.c.
    Move 1394-independent module initialization code to firedtv-dvb.c.

    This prepares interfacing with drivers/firewire.

Sun Feb 15 15:33:17 CET 2009
firedtv: amend Kconfig menu prompt

Sun Feb 15 15:33:17 CET 2009
firedtv: remove kernel version compatibility macro

Sun Feb 15 15:33:17 CET 2009
firedtv: combine header files

    avc.h and firedtv-*.h are small and currently not shared with other
    drivers, hence concatenate them all into firedtv.h.

Sun Feb 15 15:33:17 CET 2009
firedtv: misc style touch-ups

    Standardize on lower-case hexadecimal constants.  Adjust whitespace.
    Omit unnecessary pointer type casts and an unnecessary list head
    initialization.  Use dev_printk.

Wed Feb 11 21:21:04 CET 2009
firedtv: avc, ci: remove unused constants

Wed Feb 11 21:21:04 CET 2009
firedtv: avc: remove bitfields from read descriptor response operands

    Don't use bitfields in struct types of on-the-wire data.

Wed Feb 11 21:21:04 CET 2009
firedtv: avc: remove bitfields from DSD command operands

    Don't use bitfields in struct types of on-the-wire data.

Wed Feb 11 21:21:04 CET 2009
firedtv: avc: header file cleanup

    Remove unused constants and declarations.
    Move privately used constants into .c files.

Wed Feb 11 21:21:04 CET 2009
firedtv: avc: remove bitfields from FCP frame types

    Don't use bitfields in struct types of on-the-wire data.

    Also move many privately used constants from avc.h to avc.c
    and remove some unused constants.

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: avc: fix offset in avc_tuner_get_ts

    The parentheses were wrong.  It didn't matter though because this code
    only writes a 0 into an area which is already initialized to 0.

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: avc: reduce stack usage, remove two typedefs

    It is safe to share a memory buffer for command frame and response frame
    because the response data come in after the command frame was last used.

    Even less stack would be required if only the actual required frame size
    instead of the entire FCP register size was allocated.

    Also, rename the defined types AVCCmdFrm and AVCRspFrm to
    struct avc_command_frame and struct avc_response_frame.
    TODO:  Remove the bitfields in these types.

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: cmp: move code to avc

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: iso: move code to firedtv-1394

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: iso: remove unnecessary struct type definitions

Sun, 18 Jan 2009 16:30:00 +0100 (CET)
firedtv: iso: style changes and fixlets

    Add cleanup after failure in setup_iso_channel.
    Replace printk() by dv_err().
    Decrease indentation level in rawiso_activity_cb().
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Combination of the following changes:

Sat, 17 Jan 2009 14:47:34 +0100
firedtv: rename variables and functions from firesat to firedtv
Signed-off-by: Rambaldi <Rambaldi@xs4all.nl>

    Additional changes by Stefan Richter:

    Renamed struct firedtv *firedtv to struct firedtv *fdtv and
    firedtv_foo_bar() to fdtv_foo_bar() for brevity.

Sat, 17 Jan 2009 13:07:44 +0100
firedtv: rename files from firesat to firedtv
Signed-off-by: Rambaldi <Rambaldi@xs4all.nl>

    Additional changes by Stefan Richter:

    Name the directory "firewire" instead of "firedtv".
    Standardize on "-" instead of "_" in file names, because that's what
    drivers/firewire/ and drivers/media/dvb/dvb-usb/ use too.
    Build fix.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

SPIN_LOCK_UNLOCKED is deprecated.  The following makes the change suggested
in Documentation/spinlocks.txt
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

There was a bug causing the initialization to fail if adapter number was
greater than zero. The adapter was however registered which caused the driver
to oops the second time initialization was tried.
Signed-off-by: Henrik Kurelid <henrik@kurelid.se>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Parsed and used the length_field() of the PMT message instead of using
the length field of the message struct, which does not seem to be filled
correctly by e.g. MythTV.
Signed-off-by: Henrik Kurelid <henrik@kurelid.se>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

The SystemId of the ca_info message was filled with garbage.
It now returns what the card returns.
Signed-off-by: Henrik Kurelid <henrik@kurelid.se>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Combination of the following changes:

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: increase FCP frame length for DVB-S2 tune QSPK

    The last three bytes didn't go out to the wire.
    Effect of the fix not yet tested.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: replace mdelay by msleep

    These functions can sleep (and in fact sleep for the duration of a whole
    FCP transaction).  Hence msleep is more appropriate here.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: trivial reorganization in avc_api

    Reduce nesting level by factoring code out of avc_tuner_dsd() into
    helper functions.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: trivial cleanups in avc_api

    Use dev_err(), no CamelCase function names, adjust comment style, put
    #if 0 around unused code and add FIXME comments, standardize on
    lower-case hexadecimal constants, use ALIGN() for some frame length
    calculations, make a local function static...

    The code which writes FCP command frames and reads FCP response frames
    is not yet brought into canonical kernel coding style because this
    involves changes of typedefs (on-the-wire bitfields).

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: don't retry oPCR updates endlessly

    In the theoretical case that the target node wasn't handling the lock
    transactions as expected or there was continued interference by other
    initiating nodes, these functions wouldn't return for ages.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: remove bitfield typedefs from cmp, fix for big endian CPUs

    Use macros/ inline functions/ standard byte order accessors to read and
    write oPCR register values (big endian bitfields, on-the-wire data).
    The new code may not be the ultimate optimum, but it doesn't occur in a
    hot path.

    This fixes the CMP code for big endian CPUs.  So far I tested it only on
    a little endian CPU though.

    For now, include <asm/byteorder.h> instead of <linux/byteorder.h>
    because drivers/ieee1394/*.h also include the former.  I will fix this
    in drivers/ieee1394 and firedtv later.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: trivial cleanups in cmp

    Reduce nesting level by means of early exit and goto.
    Remove obsolete includes, use dev_err(), no CamelCase function names...

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: trivial cleanups in firesat-ci

    Whitespace, variable names, comment style...

    Also, use dvb_generic_open() and dvb_generic_release() directly as
    our hooks in struct file_operations because firedtv's wrappers merely
    called these generic functions.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: remove CA debug code

    This looks like it is not necessary to have available for endusers who
    cannot patch kernels for bug reporting and tests of fixes.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: remove AV/C debug code

    This looks like it is not necessary to have available for endusers who
    cannot patch kernels for bug reporting and tests of fixes.

Sun, 2 Nov 2008 13:45:00 +0100 (CET)
firedtv: remove various debug code

    Most of this was already commented out.  And that which wasn't is not
    relevant in normal use.

Mon, 29 Sep 2008 19:22:48 +0200 (CEST)
firedtv: register input device as child of a FireWire device

    Instead of one virtual input device which exists for the whole lifetime
    of the driver and receives events from all connected FireDTVs, register
    one input device for each firedtv device.  These input devices will show
    up as children of the respective firedtv devices in the sysfs hierarchy.

    However, the implementation falls short because of a bug in userspace:
    Udev's path_id script gets stuck with 100% CPU utilization, maybe
    because of an assumption about the maximum ieee1394 device hierarchy
    depth.

    To avoid this bug, we use the fw-host device instead of the proper
    unit_directory device as parent of the input device.

    There is hope that the port to the new firewire stack won't be inhibited
    by this userspace bug because there are no fw-host devices there.

Mon, 29 Sep 2008 19:21:52 +0200 (CEST)
firedtv: fix string comparison and a few sparse warnings

    Sparse found a bug:
    	while ((kv_buf + kv_len - 1) == '\0')
    should have been
    	while (kv_buf[kv_len - 1] == '\0')
    We fix it by a better implementation without a temporary copy.

    Also fix sparse warnings of 0 instead of NULL and signedness mismatches.

Mon, 29 Sep 2008 19:21:20 +0200 (CEST)
firedtv: remove unused struct members

    and redefine an int as a bool.

Mon, 29 Sep 2008 19:20:36 +0200 (CEST)
firedtv: fix initialization of dvb_frontend.ops

    There was a NULL pointer reference if no dvb_frontend_info was found.

    Also, don't directly assign struct typed values to struct typed
    variables.  Instead write out assignments to individual strcut members.
    This reduces module size by about 1 kB.

Mon, 29 Sep 2008 19:19:41 +0200 (CEST)
firedtv: remove unused dual subunit code from initialization

    No FireDTVs with more than one subunit exists, hence simplify the
    initialization for the special case of one subunit.  The driver was able
    to check for more than one subunit but was broken for more than two
    subunits.

    While we are at it, add several missing cleanups after failure, and
    include a few dynamically allocated structures diretly into struct
    firesat instead of allocating them separately.

Mon, 29 Sep 2008 19:19:08 +0200 (CEST)
firedtv: add vendor_id and version to driver match table

    Now that nodemgr was enhanced to match against the root directory's
    vendor ID if there isn't one in the unit directory, use this to
    prevent firedtv to be bound to wrong devices by accident.

    Also add the AV/C software version ID to the match flags for
    completeness; specifier ID and software only make sense as a pair.

Mon, 29 Sep 2008 19:18:30 +0200 (CEST)
firedtv: use hpsb_node_read(), _write(), _lock()

    because they are simpler and treat the node generation more correctly.
    While we are at it, clean up and simplify surrounding code.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

hpsb_read, hpsb_write, hpsb_lock are sleeping functions which nobody is
in danger to use in atomic context.  Besides, in_interrupt does not
cover all types of atomic context.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

While Module_Vendor_ID in the configuration ROM's root directory is
mandatory, there often aren't vendor IDs in unit directories.  This
affects the new firedtv driver which is meant to be auto-loaded and
matched only for vendor-specific devices.

We now always copy ne->vendor_id into ud->vendor_id before we scan a
unit directory (and fill in a possibly present vendor ID from there).
This way, the root directory's vendor ID is used as fallback in the
"uevent" environment for modprobe'ing per module alias when a node was
plugged in, and in the driver match routine when protocol drivers are
bound to unit directories.  It will however not be used as sysfs
attribute of a unit directory device.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

These will be used by the firedtv driver.  Like hpsb_node_write() they
are much better APIs for high-level drivers than hpsb_write() and its
siblings --- easier to use correctly and also terser.

Unlike hspb_node_write(), the two new functions will only be used by
one call site.  Hence make them static inline instead of exported
symbols.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

A compiler barrier (explicit on the read side, implicit on the write
side) is not quite enough for what has to be accomplished here.  Use
hardware memory barriers on systems which need them.

(Of course a full fix of generation handling would require much more
than this.  The ieee1394 core's bus generation counter had to be tied to
the controller's bus generation counter; cf. Kristian's stack.  It's
just that I have other current business with the code around these
barrier()s, so why not do at least this small fix.)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Combination of the following changes:

Tue, 26 Aug 2008 00:17:30 +0200 (CEST)
firedtv: fix remote control input

    and update the scancode-to-keycode mapping to a current model.  Per
    default, various media key keycodes are emitted which closely match what
    is printed on the remote.  Userland can modify the mapping by means of
    evdev ioctls.  (Not tested.)

    The old scancode-to-keycode mapping is left in the driver but cannot be
    modified by ioctls.  This preserves status quo for old remotes.

Tue, 26 Aug 2008 00:11:28 +0200 (CEST)
firedtv: replace tasklet by workqueue job

    Non-atomic context is a lot nicer to work with.

Sun, 24 Aug 2008 23:30:00 +0200 (CEST)
firedtv: move some code back to ieee1394 core

    Partially reverts "ieee1394: remove unused code" of Linux 2.6.25.

Sun, 24 Aug 2008 23:29:30 +0200 (CEST)
firedtv: replace semaphore by mutex

    firesat->avc_sem and ->demux_sem have been used exactly like a mutex.
    The only exception is the schedule_remotecontrol tasklet which did a
    down_trylock in atomic context.  This is not possible with
    mutex_trylock; however the whole remote control related code is
    non-functional anyway at the moment.  This should be fixed eventually,
    probably by turning the tasklet into a worqueue job.

    Convert everything else from semaphore to mutex.

    Also rewrite a few of the affected functions to unlock the mutex at a
    single exit point, instead of in several branches.

Sun, 24 Aug 2008 23:28:45 +0200 (CEST)
firedtv: some header cleanups

    Unify #ifndef/#define/#endif guards against multiple inclusion.
    Drop extern keyword from function declarations.
    Remove #include's into header files where struct declarations suffice.

    Remove unused ohci1394 interface and related unused ieee1394 interfaces.

    Add a few missing #include's and remove a few apparently obsolete ones.
    Sort them alphabetically.

Sun, 24 Aug 2008 23:27:45 +0200 (CEST)
firedtv: nicer registration message and some initialization fixes

    Print the correct name in dvb_register_adapter().

    While we are at it, replace two switch cascades by one for loop, remove
    a superfluous member of struct firesat and of two unused arguments of
    AVCIdentifySubunit(), and fix bogus kfree's in firesat_dvbdev_init().

Tue, 26 Aug 2008 14:24:17 +0200 (CEST)
firesat: rename to firedtv

    Suggested by Andreas Monitzer.  Besides DVB-S/-S2 receivers, the driver
    also supports DVB-C and DVB-T receivers, hence the previous project name
    is too narrow now.

    Not yet done:  Rename source directory, files, types, variables...

Sun, 24 Aug 2008 23:26:23 +0200 (CEST)
firesat: add missing copyright notes

    Reported by Andreas Monitzer and Christian Dolzer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>