Commit Graph

13 Commits

Author SHA1 Message Date
Marc Kleine-Budde e39428d53d i2c-imx: do not allow interruptions when waiting for I2C to complete
The i2c_imx_trx_complete() function is using
wait_event_interruptible_timeout() to wait for the I2C controller to
signal that it has completed an I2C bus operation. If the process that
causes the I2C operation receives a signal, the wait will be
interrupted, returning an error. It is better to let the I2C operation
finished before handling the signal (i.e. returning into userspace).

It is safe to use wait_event_timeout() instead, because the timeout
will allow the process to exit if the I2C bus hangs. It's also better
to allow the I2C operation to finish, because unacknowledged I2C
operations can cause the I2C bus to hang.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-10-18 01:29:04 +01:00
Arnaud Patard da9c99fc32 i2c-imx: fix error handling
- Return -ETIMEDOUT on bus busy error
- Fix timeout test "time_after(jiffies, orig_jiffies + HZ / 1000)" :
  By default, HZ=100 on arm. This means that this test has no chances to
  work and may result in a dead loop. Set timeout to 500ms.
- Don't try to send a new message if we failed to transmit
  previous one. This was preventing to recover from error on my system

Signed-off-by: Arnaud Patard <apatard@mandriva.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-04-20 01:16:57 +01:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Uwe Kleine-König 96eb7164e3 i2c/imx: don't add probe function to the driver struct
Having a pointer to the probe function is unnecessary when using
platform_driver_probe and yields a section mismatch warning after
removing the white list entry "*driver" for
{ .data$, .data.rel$ } -> { .init.* } mismatches in modpost.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-03-07 22:02:16 +00:00
Uwe Kleine-König 4927fbf11d i2c: imx: call ioremap only after request_mem_region
accordingly adapt order of release_mem_region and release_mem_region on
remove.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: Richard Zhao <linuxzsc@gmail.com>
Cc: Darius Augulis <augulis.darius@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: linux-i2c@vger.kernel.org
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-01-24 15:25:57 +00:00
Valentin Longchamp a1ee06b729 i2c: mxc: let time to generate stop bit
After generating the stop bit by changing MSTA from 1 to 0,
the i2c_imx->stopped was immediatly set to 1. The second test
on i2c_imx->stopped then is correct and the controller never
waits if the bus is busy. This patch corrects this.

On mx31moboard, stop bit was not generated on single write transfers.
This was kept unnoticed as other transfers are made afterwards that
help the write recipient to resynchronize.

Thanks to Philippe and Michael for the debugging.

Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>
Signed-off by: Philippe Rétornaz <philippe.retornaz@epfl.ch>
Reported-by: Michael Bonani <michael.bonani@epfl.ch>
Acked-by; Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-01-24 15:25:56 +00:00
Richard Zhao db3a3d4ef7 i2c: imx: disable clock when it's possible to save power.
Enable clock before START, disable it after STOP.

Signed-off-by: Richard Zhao <linuxzsc@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-11-02 23:28:47 +00:00
Richard Zhao a4094a76e6 i2c: imx: only imx1 needs disable delay
check cpu_is_mx1() when disable delay.

Signed-off-by: Richard Zhao <linuxzsc@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-11-02 23:28:47 +00:00
Richard Zhao 43309f3b52 i2c: imx: check busy bit when START/STOP
The controller can't do anything else before it actually generates START/STOP.
So we check busy bit to make sure START/STOP is successfully finished.

If we don't check busy bit, START/STOP may fail on some fast CPUs.

Signed-off-by: Richard Zhao <linuxzsc@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-11-02 23:28:46 +00:00
Wolfram Sang 5d3f33318a [PATCH] i2c-imx: make bus available early
As I2C is used by PMICs also, make the busses available early via
subsys_initcall().

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-09-19 23:36:56 +01:00
Wolfram Sang 65de394df2 i2c: imx: Make disable_delay a per-device variable
'disable_delay' was static which is wrong as it is calculated using the per-device
bus speed. This patch turns 'disable_delay' into a per-device variable.

Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Darius Augulis <augulis.darius@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-04-07 10:23:34 +01:00
Darius Augulis 309c18d2cd i2c: imx: Add missing request_mem_region in probe()
Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
[ben-linux@fluff.org: fix minor patch fault in remove]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-04-07 10:18:33 +01:00
Darius Augulis aa11e38ce6 i2c: iMX/MXC support
Implementation of I2C Adapter/Algorithm Driver for I2C Bus integrated
in Freescale's i.MX/MXC processors.

Signed-off-by: Darius Augulis <augulis.darius@gmail.com>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-04-07 10:18:32 +01:00