Under certain rare conditions, I2C_STAT[13].RDR bit may be set
and the corresponding interrupt fire, even there is no data in
the receive FIFO, or the I2C data transfer is still ongoing.
These spurious RDR events must be ignored by the software.

This patch handles and ignores RDR spurious interrupts.

The below sequence is required in interrupt handler for
handling this errata:
1. If RDR is set to 1, clear RDR
2. Read I2C status register and check for BusBusy bit. If BusBusy
bit is set, skip remaining steps.
3. If BusBusy bit is not set, perform read operation on I2C status
register.
4. If RDR is set, clear the same. Check RDR again and clear if it sets
RDR bit again.
5. Perform I2C Data Read operation N number of times(where N is value
read from the register BUFSTAT-RXSTAT bit fields).

Note:
This errata is not applicable for omap2420 and omap4.
It is applicable for:
1. omap2430
2. omap34xx(including omap3630).
Signed-off-by: NManjunatha GK <manjugk@ti.com>
Cc: Hema Kalliguddi <hemahk@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Aaro Koskinen <Aaro.Koskinen@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The errata 1.153 workaround is busy waiting on XUDF bit in interrupt
context, which may lead to kernel hangs. The problem can be reproduced
by running the bus with wrong (too high) speed.
Signed-off-by: NAlexander Shishkin <virtuoso@slind.org>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This is to avoid insanely long lines and levels of indentation.
Signed-off-by: NAlexander Shishkin <virtuoso@slind.org>
Cc: Nishant Menon <nm@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

While waiting for completion of the i2c transfer, the
MPU could hit OFF mode and cause several msecs of
delay that made i2c transfers fail more often. The
extra delays and subsequent re-trys cause i2c clocks
to be active more often. This has also an negative
effect on power consumption.

Created a mechanism for passing and using the
constraint setting function in driver code. The used
mpu wake up latency constraints are now set individually
per bus, and they are calculated based on clock rate
and fifo size.

Thanks to Jarkko Nikula, Moiz Sonasath, Paul Walmsley,
and Nishanth Menon for tuning out the details of
this patch.

Updates by Kevin as requested by Tony:

- Remove omap_set_i2c_constraint_func() in favor of conditionally
  adding the flag in omap_i2c_add_bus() in order to keep all the OMAP
  conditional checking in a single location.
- Update set_mpu_wkup_lat prototypes to match OMAP PM layer so
  OMAP PM function can be used directly in pdata.

Cc: Moiz Sonasath <m-sonasath@ti.com>
Cc: Jarkko Nikula <jhnikula@gmail.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: NKalle Jokiniemi <kalle.jokiniemi@digia.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This patch is rebased version of earlier post to add I2C
driver support to OMAP4 platform. On OMAP4, all
I2C register address offsets are changed from OMAP1/2/3 I2C.
In order to not have #ifdef's at various places in code,
as well as to support multi-OMAP build, an array is created
to hold the register addresses with it's offset.

This patch was submitted, reviewed and acked on mailing list
already. For more details refer below link
http://www.mail-archive.com/linux-i2c@vger.kernel.org/msg02281.html

This updated verion has a depedancy on "Add support for 16-bit registers"
posted on linux-omap. Below is the patch-works link for the same

http://patchwork.kernel.org/patch/72295/Signed-off-by: NSyed Rafiuddin <rafiuddin.syed@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NKevin Hilman <khilman@deeprootsystems.com>
Reviewed-by: NPaul Walmsley <paul@pwsan.com>
Cc: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Commit d84d3ea3 added register shift to allow
also 16-bit register access. However, omap_i2c_unidle() is called before these
are set which causes the following OOPS:

    Unhandled fault: alignment exception (0x801) at 0xfa070009
    Internal error: : 801 [#1]
    last sysfs file:
    Modules linked in:
    CPU: 0    Not tainted  (2.6.34-rc2-00052-gae6be51e #3)
    PC is at omap_i2c_unidle+0x44/0x138
    LR is at trace_hardirqs_on_caller+0x158/0x18c
    pc : [<c01cd2c4>]    lr : [<c00743f8>]    psr: 20000013
    sp : cfc2bf10  ip : 00000009  fp : 00000000
    r10: 00000000  r9 : 00000000  r8 : c0378560
    r7 : c0378b88  r6 : c0378558  r5 : cfcadc00  r4 : cfcadc00
    r3 : 00000009  r2 : fa070000  r1 : 00000000  r0 : 00000000
    Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
    Control: 10c5387f  Table: 80004019  DAC: 00000017
    Process swapper (pid: 1, stack limit = 0xcfc2a2e8)
    Stack: (0xcfc2bf10 to 0xcfc2c000)
    bf00:                                     c0372cf8 c027225c 00000000 c0a69678
    bf20: cfc3e508 c0500898 c0378560 c0378560 c0500898 cfcac8c0 c04fc280 c017d4f4
    bf40: c0378560 c017c63c c0378560 c0378594 c0500898 cfcac8c0 c04fc280 c017c754
    bf60: 00000000 c017c6f4 c0500898 c017beac cfc16a5c cfc3fd94 c0023448 c0500898
    bf80: c0500898 c017b7d4 c032dc7f 00000093 cfc28d40 c0023448 00000000 c0500898
    bfa0: 00000000 00000000 00000000 c017ca48 c0023448 00000000 c001d274 00000000
    bfc0: 00000000 c002b344 00000031 00000000 00000000 00000192 00000000 c0023448
    bfe0: 00000000 00000000 00000000 c0008578 00000000 c002c304 ffdfffff ffffffff
    [<c01cd2c4>] (omap_i2c_unidle+0x44/0x138) from [<c027225c>] (omap_i2c_probe+0x1a4/0x398)
    [<c027225c>] (omap_i2c_probe+0x1a4/0x398) from [<c017d4f4>] (platform_drv_probe+0x18/0x1c)
    [<c017d4f4>] (platform_drv_probe+0x18/0x1c) from [<c017c63c>] (driver_probe_device+0xc0/0x178)
    [<c017c63c>] (driver_probe_device+0xc0/0x178) from [<c017c754>] (__driver_attach+0x60/0x84)
    [<c017c754>] (__driver_attach+0x60/0x84) from [<c017beac>] (bus_for_each_dev+0x44/0x74)
    [<c017beac>] (bus_for_each_dev+0x44/0x74) from [<c017b7d4>] (bus_add_driver+0x9c/0x218)
    [<c017b7d4>] (bus_add_driver+0x9c/0x218) from [<c017ca48>] (driver_register+0xa8/0x130)
    [<c017ca48>] (driver_register+0xa8/0x130) from [<c002b344>] (do_one_initcall+0x5c/0x1b8)
    [<c002b344>] (do_one_initcall+0x5c/0x1b8) from [<c0008578>] (kernel_init+0x90/0x144)
    [<c0008578>] (kernel_init+0x90/0x144) from [<c002c304>] (kernel_thread_exit+0x0/0x8)
    Code: e5942004 e3a0c009 e1a0331c e3a01000 (e18210b3)
    ---[ end trace 1b75b31a2719ed1c ]---

This patch moves register shift setting before any register accesses are done.
Signed-off-by: NMika Westerberg <ext-mika.1.westerberg@nokia.com>
Cc: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

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: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

A pointer to omap_i2c_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded.  Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.

An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: chandra shekhar <x0044955@ti.com>
Cc: Jason P Marini <jason.marini@gmail.com>
Cc: Syed Mohammed Khasim  <x0khasim@ti.com>
Cc: Jarkko Nikula <jarkko.nikula@nokia.com>
Cc: Juha Yrjola <juha.yrjola@solidboot.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The current i2c-omap driver is set up for 32-bit registers, which
corresponds to most OMAP devices.  However, OMAP730/850 based
devices use a 16-bit register size.

This change modifies the driver to perform a runtime CPU type check
to determine the register sizes, and uses a bit shift of either 1
or 2 bits to compute the proper register sizes for all registers.
Signed-off-by: NCory Maccarrone <darkstar6262@gmail.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Current OMAP3 I2C driver code does not follow the correct sequence for soft
reset. Due to this, lock up issues are reported during timeout/error cases.

This patch fixes above issue by disabling I2C controller as per OMAP3430 TRM
for soft reset. As per TRM, I2C controller needs to be disabled as a first
step during soft reset.

Here is correct soft reset sequence:
a. Ensure that the module is disabled
(clear the I2Ci.I2C_CON[15] I2C_EN bit to 0).
b. Set the I2Ci.I2C_SYSC[1] SRST bit to 1.
c. Enable the module by setting I2Ci.I2C_CON[15] I2C_EN bit to 1.
d. Check the I2Ci.I2C_SYSS[0] RDONE bit until it is set to 1 to
indicate the software reset is complete.

Tested on Zoom2, Zoom3, 3430SDP and 3630SDP
Signed-off-by: NManjunatha GK <manjugk@ti.com>
Signed-off-by: George, Harith<harith@ti.com>
Acked-by: Varadarajan, Charu Latha<charu@ti.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Commit ef871432... (i2c-omap: OMAP3: PM: (re)init for every transfer
to support off-mode) introduced a change which make the dev->iestate
contents be written to the OMAP_I2C_IE_REG every time omap_i2c_unidle
is called.  Previously, the state was only written if it wasn't equal
to zero.

In omap_i2c_probe, omap_i2c_unidle() is called prior to omap_i2c_init(),
in which case dev->iestate has not yet been initialized and will be set
to zero.  Having this value written to the registers causes deadlock
while booting.

As such, this change restores the original functionality.
Signed-off-by: NCory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Because of OMAP off-mode, powerdomain can go off when I2C is idle.
Save enough state, and do a re-init for each transfer.

Additional save/restore state added by Jagadeesh Bhaskar Pakaravoor
(SYSC_REG) and Aaro Koskinen (wakeup sources.)

Also, The OMAP3430 TRM states:

"During active mode (I2Ci.I2C_CON[15] I2C_EN bit is set to 1), make no
changes to the I2Ci.I2C_SCLL and I2Ci.I2C_SCLH registers.  Changes may
result in unpredictable behavior."

Hence, the I2C_EN bit should be clearer when modifying these
registers. Please note that clearing the entire I2C_CON register to
disable the I2C module is safe, because the I2C_CON register is
re-configured for each transfer.
Signed-off-by: NJouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Cc: Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Jon Hunter <jon-hunter@ti.com>
Cc: Hu Tao <taohu@motorola.com>
Cc: Xiaolong Chen <A21785@motorola.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Silicon Errata 1.153 has been fixed on OMAP 3630|4430 with the use of a later
version of I2C IP block.

The errata impacts OMAP 2420|2430|3430, enable the workaround for these based
on I2C IP block revision number instead of OMAP CPU type
Signed-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com
Reviewed-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

ACK any pending read/write interrupts before exiting the ISR either after
completing the operation [ARDY interrupt] or in case of an error
[NACK|AL interrupt]
Signed-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: NVikram Pandita <vikram.pandita@ti.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

I2C status ack for [RX]RDR and [RX]RDY could
cause race conditions of clearing the event
twice and a violation of the programing
sequence as defined in TRM This patch fixes
the same.
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

When an XRDY/XDR is hit, wait for XUDF before writing data to DATA_REG.
Otherwise some data bytes can be lost while transferring them from the
memory to the I2C interface.

Do a Busy-wait for XUDF, before writing data to DATA_REG. While waiting
if there is NACK | AL, set the appropriate error flags, ack the pending
interrupts and return from the ISR.
Signed-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: NVikram pandita <vikram.pandita@ti.com>
[ben-linux@fluff.org: fixed mail format and added i2c-omap to subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

In case of a NACK or ARDY or AL interrupt, complete the request.
There is no need to service the RRDY/RDR or XRDY/XDR interrupts.

Refer TRM SWPU114: Figure 18-31.I2C Master Transmitter Mode, Interrupt Method,
in F/S and HS Modes

http://focus.ti.com/pdfs/wtbu/SWPU114T_PrelimFinalEPDF_06_25_2009.pdfSigned-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: NVikram pandita <vikram.pandita@ti.com>
[ben-linux@fluff.org: fixed mail format and added i2c-omap to subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Fix bug in reading the I2C_BUFFSTAT register for getting byte count on RX/TX interrupt.

On Interrupt: I2C_STAT[RDR],
	read 'RXSTAT' from I2C_BUFFSTAT[8-13]
On Interrupt: I2C_STAT[XDR]
	read 'TXSTAT' from I2C_BUFFSTAT[0-5]
Signed-off-by: NJagadeesh Pakaravoor <j-pakaravoor@ti.com>
Signed-off-by: NMoiz Sonasath <m-sonasath@ti.com>
Signed-off-by: NVikram pandita <vikram.pandita@ti.com>
[ben-linux@fluff.org: fixed mail format and added i2c-omap to subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

strlcpy() will always null terminate the string.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Use the function resource_size, which reduces the chance of introducing
off-by-one errors in calculating the resource size.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
struct resource *res;
@@

- (res->end - res->start) + 1
+ resource_size(res)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Hi Ben,

Can you please queue this fix?

Thanks,

Tony

>From ffe2b2cdf6283770b70a197e3748c6b40a1006be Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony@atomide.com>
Date: Wed, 17 Jun 2009 13:14:23 +0300
Subject: [PATCH] i2c-omap: Fix build breaking typo in cpu_is_omap_2430

Commit 84bf2c86 introduced a typo, it should be cpu_is_omap2430
instead. The typo was probably caused by a mismerge.

Without this patch all omaps fail to build with:
error: implicit declaration of function 'cpu_is_omap_2430'
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This replace all instances in the i2c busses tree of
res->end - res->start + 1 with the handy macro resource_size(res)
from ioport.h (coming in from platform_device.h).

This was created with a simple
sed -i -e 's/\([a-z]*\)->end *- *[a-z]*->start *+ *1/resource_size(\1)/g'

Then manually replacing the PXA redefiniton of the same kind
of macro manually. Recompiled some ARM defconfigs I could find to
make a rough test so it shouldn't break anything, though I
couldn't see exactly which configs you need for all the drivers.
Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Use longer noise filter period for fast and standard mode. Based on an
earlier patch by Eero Nurkkala.
Signed-off-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Fix scll/sclh calculations for HS and fast modes. Currently the driver
uses equal (roughly) low/high times which will result in too short
low time.

OMAP3430 TRM gives the following equations:

	F/S: tLow  = (scll + 7) * internal_clk
	     tHigh = (sclh + 5) * internal_clk
	HS:  tLow  = (scll + 7) * fclk
	     tHigh = (sclh + 5) * fclk

Furthermore, the I2C specification sets the following minimum values
for HS tLow/tHigh for capacitive bus loads 100 pF (maximum speed 3400)
and 400 pF (maximum speed 1700):

	speed	tLow		tHigh
	3400	160 ns		60 ns
	1700	320 ns		120 ns

and for F/S:

	speed	tLow		tHigh
	400	1300 ns		600 ns
	100	4700 ns		4000 ns

By using duty cycles 33/66 (HS, F) and 50/50 (S) we stay above these
minimum values.
Signed-off-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

By providing a dummy ick for OMAP1510 and OMAP310, we avoid having
SoC conditional clock information in i2c-omap.c.  Also, fix the
error handling by making sure we propagate the error returned via
clk_get().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On OMAP1, the I2C functional clock (fck) is the armxor_ck, so there's
no need to get "armxor_ck" separately.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The probe function used a pointer to the interrupt
handler to register as a 'void *', change it to the
proper type of irq_handler_t.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

I2C_WE registers were not configured, which caused huge delays in
I2C operations while cpu idle was enabled and omap entered WFI.

This patch enables all I2C wakeup sources.
Signed-off-by: NKalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

The I2C controller clears its OCP_SYSCONFIG register after an OCP soft reset.
Reprogram OCP_SYSCONFIG for maximum power savings on rev3.6 controllers
and beyond.  On 2430, this involves setting the module AUTOIDLE bit.
On 3430, this includes module AUTOIDLE, wakeup enable, slave smart-idle,
and considers only the module functional clock state for idle-ack.

Boot-tested on 2430SDP and 3430SDP.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

i2c-omap discriminates only between "revision 1" or "greater than
revision 1."  A following patch introduces code that must also
discriminate between rev2.x, rev3.6, and rev3.12 controllers.  Support
this by storing the full revision data from the I2C_REV register, rather
than just a single bit.

The revision definitions may need to be extended for other ES levels
that aren't currently available here.  rev3.6 is what's present on the
2430SDP here (unknown ES revision); rev3.12 is used on the 3430ES2
here.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

omap_i2c_unidle() and omap_i2c_idle() are called recursively during
omap_i2c_probe().  This is evidently unexpected and will wipe
out the I2C interrupt enable register the second time that
omap_i2c_idle() is called consecutively.  Any I2C transactions
following a probe of a bus with at least one device on it will then
time out.

Fix by moving omap_i2c_idle() further up in omap_i2c_probe().  Ensure
the I2C controller is marked as idle before the probe starts.  Also
attempt to catch future reappearances of this bug early in development
by warning in omap_i2c_{un,}idle() when they are called recursively.

Problem reported by David Brownell <david-b@pacbell.net>.

Tested on 3430SDP and 2430SDP.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Acked-by; Steve Sakoman <steve@sakoman.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Minor sparse, checkpatch and formatting clean-up. Also update copyrights.
Signed-off-by: NTony Lindgren <tony@atomide.com>

Skip compiling OMAP15xx I2C ISR for non-OMAP15xx builds.  Saves 400 bytes
of text for most OMAP builds.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Mark functions called only at init time as __init.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Add support for omap34xx
Signed-off-by: Nchandra shekhar <x0044955@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Based on an earlier patch from Nishant Menon:

- Transfers can use FIFO on FIFO capable devices
- Prevents errors for HSI2C if FIFO is not used
- Implemented errenous handling of STT-STP handling on SDP2430

Also merged in is a fix from Jaron Marini to fix occasional i2c
hang if OMAP_I2C_CON_STT remains asserted.
Signed-off-by: NJason P Marini <jason.marini@gmail.com>
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Omap2430 has additional support for high-speed I2C.

This patch moves I2C speed parameter (from module) to platform data.
Also added basic High Speed support based on I2C bus speed.

This patch is tested for high speed I2C (with TWL4030 Keypad) and works as
expected.

Also change the 2430 i2chs_fck names to use the standard naming.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NSyed Mohammed Khasim  <x0khasim@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

omap_i2c_idle() sets an internal flag, "dev->idle", instructing its
ISR to decline interrupts.  It sets this flag before it actually masks
the interrupts on the I2C controller.  This is problematic, since an
I2C interrupt could arrive after dev->idle is set, but before the
interrupt source is masked.  When this happens, Linux disables the I2C
controller's IRQ, causing all future transactions on the bus to fail.

Symptoms, happening on about 7% of boots:

   irq 56: nobody cared (try booting with the "irqpoll" option)
   <warning traceback here>
   Disabling IRQ #56
   i2c_omap i2c_omap.1: controller timed out

In omap_i2c_idle(), this patch sets dev->idle only after the interrupt
mask write to the I2C controller has left the ARM write buffer.
That's probably the major offender.  For additional prophylaxis, in
omap_i2c_unidle(), the patch clears the dev->idle flag before
interrupts are enabled, rather than afterwards.

The patch has survived twenty-two reboots on the 3430SDP here without
wedging I2C1.  Not absolutely dispositive, but promising!
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

If there is a signal pending and wait_for_completion_interruptible_timeout
terminates with -ERESTARTSYS, we return and disable the i2c clocks in
omap_i2c_xfer.

If we terminate before sending last i2c message with a stop condition, the
bus remains busy and we are not able to send new messages into bus with
successive omap_i2c_xfer calls. Therefore a pending signal is not caught
here and we return only because of timeout or i2c error.
Signed-off-by: NJarkko Nikula <jarkko.nikula@nokia.com>
Signed-off-by: NJuha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>