Commit graph

532 commits

Author SHA1 Message Date
Wolfram Sang
6b110d13aa i2c-pca-platform: Use defaults if no platform_data given
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-03-28 21:34:45 +01:00
Wolfram Sang
2378bc09b9 i2c-algo-pca: Use timeout for checking the state machine
We now timeout also if the state machine does not change within the
given time. For that, the driver-specific completion-functions are
extended to return true or false depending on the timeout. This then
gets checked in the algorithm.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-03-28 21:34:45 +01:00
Wolfram Sang
8e99ada8de i2c-algo-pca: Rework waiting for a free bus
Waiting for a free bus now accepts the timeout value in jiffies and does
proper checking using time_before.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-03-28 21:34:45 +01:00
Marco Aurelio da Costa
eff9ec95ef i2c-algo-pca: Add PCA9665 support
Add support for the PCA9665 I2C controller.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-03-28 21:34:44 +01:00
Jean Delvare
98a679cad5 i2c-davinci: Fix timeout handling
Properly set the adapter timeout value in jiffies, and then use that
value in the driver, rather than a hard-coded constant.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Troy Kisky <troy.kisky@boundarydevices.com>
Cc: Kevin Hilman <khilman@mvista.com>
2009-03-28 21:34:43 +01:00
Jean Delvare
8a52c6b4d5 i2c: Adapter timeout is in jiffies
i2c_adapter.timeout is in jiffies. Fix all drivers which thought
otherwise. It didn't really matter as long as the value was only used
inside the driver, but soon i2c-core will use it too so it must have
the proper unit.

Note: for the i2c-mpc driver, this fixes a bug in polling mode.
Timeout would trigger after 1 jiffy, which is most probably not what
the author wanted.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Clifford Wolf <clifford@clifford.at>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Cc: Stefan Roese <sr@denx.de>
Acked-by: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Mark A. Greer <mgreer@mvista.com>
2009-03-28 21:34:43 +01:00
Frank Seidel
154d22b04a i2c: Add missing KERN_* constants to printks
According to kerneljanitors todo list all printk calls (beginning
a new line) should have an according KERN_* constant.
Those are the missing pieces here for the i2c subsystem.

Signed-off-by: Frank Seidel <frank@f-seidel.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-03-28 21:34:42 +01:00
Jean Delvare
d2dd14ac18 i2c-nforce2: Add support for MCP67, MCP73, MCP78S and MCP79
The MCP78S and MCP79 appear to be compatible with the previous nForce
chips as far as the SMBus controller is concerned. The MCP67 and MCP73
were not tested yet but I'd be very surprised if they weren't
compatible too.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Oleg Ryjkov <olegr@olegr.ca>
Cc: Malcolm Lalkaka <mlalkaka@gmail.com>
Cc: Zbigniew Luszpinski <zbiggy@o2.pl>
2009-03-28 21:34:41 +01:00
Linus Torvalds
f41bf2ab99 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] fix lots of ARM __devexit sillyness
  [ARM] 5417/1: Set the correct cacheid for ARMv6 CPUs with ARMv7 style MMU
  [ARM] 5416/1: Use unused address in v6_early_abort
  [ARM] 5411/1: S3C64XX: Fix EINT unmask
  [ARM] at91: fix for Atmel AT91 powersaving
  [ARM] RiscPC: Fix etherh oops
2009-03-03 14:12:41 -08:00
Russell King
bdf602bd73 [ARM] fix lots of ARM __devexit sillyness
`iop_adma_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o
`mv_xor_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o
`mv64xxx_i2c_unmap_regs' referenced in section `.devinit.text' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o
`mv64xxx_i2c_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o
`orion_nand_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o
`pxafb_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-03 21:04:04 +00:00
Russell King
531660ef56 Add i2c_board_info for RiscPC PCF8583
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>
2009-02-24 19:19:50 +01:00
Jean Delvare
082a4cf809 i2c: Make sure i2c_algo_bit_data.timeout is HZ-independent
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>
2009-02-24 19:19:49 +01:00
Roel Kluin
a746b578d8 i2c: Timeouts reach -1
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>
2009-02-24 19:19:48 +01:00
Jean Delvare
1745522ccb i2c: Delete many unused adapter IDs
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-01-26 21:19:52 +01:00
Jean Delvare
66c7acf61d i2c: Use snprintf to set adapter names
Use snprintf instead of sprintf to set adapter names, it's safer.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-01-07 14:29:18 +01:00
Jean Delvare
1561bfe59c Input: apanel - convert to new i2c binding
Convert the apanel driver to the new i2c device driver binding model,
as the legacy model is going away soon. In the new model, the apanel
driver is no longer scanning all the i2c adapters, instead the
relevant bus driver (i2c-i801) is instantiating the device as needed.

One side benefit is that the apanel driver will now load automatically
on all systems where it is needed.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
2009-01-07 14:29:17 +01:00
Jean Delvare
e1995f65be i2c: Drop I2C_CLASS_ALL
I2C_CLASS_ALL is almost never what bus driver authors really want.
These i2c classes are really only about which devices must be probed,
not what devices can be present. As device drivers get converted to the
new i2c device driver model, only a few device types will keep relying
on probing.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
2009-01-07 14:29:16 +01:00
Jean Delvare
22e965c2ae i2c: Get rid of remaining bus_id access
Use dev_name(dev) instead of accessing dev.bus_id directly, as the
latter is going away soon.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
2009-01-07 14:29:16 +01:00
Linus Torvalds
c58bd34d00 Merge branch 'i2c-next' of git://aeryn.fluff.org.uk/bjdooks/linux
* 'i2c-next' of git://aeryn.fluff.org.uk/bjdooks/linux:
  i2c-omap: fix type of irq handler function
  i2c-s3c2410: Change IRQ to be plain integer.
  i2c-s3c2410: Allow more than one i2c-s3c2410 adapter
  i2c-s3c2410: Remove default platform data.
  i2c-s3c2410: Use platform data for gpio configuration
  i2c-s3c2410: Fixup style problems from checkpatch.pl
  i2c-omap: Enable I2C wakeups for 34xx
  i2c-omap: reprogram OCP_SYSCONFIG register after reset
  i2c-omap: convert 'rev1' flag to generic 'rev' u8
  i2c-omap: fix I2C timeouts due to recursive omap_i2c_{un,}idle()
  i2c-omap: Clean-up i2c-omap
  i2c-omap: Don't compile in OMAP15xx I2C ISR for non-OMAP15xx builds
  i2c-omap: Mark init-only functions as __init
  i2c-omap: Add support for omap34xx
  i2c-omap: FIFO handling support and broken hw workaround for i2c-omap
  i2c-omap: Add high-speed support to omap-i2c
  i2c-omap: Close suspected race between omap_i2c_idle() and omap_i2c_isr()
  i2c-omap: Do not use interruptible wait call in omap_i2c_xfer_msg

Fix up apparently-trivial conflict in drivers/i2c/busses/i2c-s3c2410.c
2009-01-05 18:58:06 -08:00
Ben Dooks
88f60f62f3 Merge branch 'i2c-next-s3c' into i2c-next 2009-01-05 10:54:50 +00:00
Linus Torvalds
14a3c4ab0e Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (407 commits)
  [ARM] pxafb: add support for overlay1 and overlay2 as framebuffer devices
  [ARM] pxafb: cleanup of the timing checking code
  [ARM] pxafb: cleanup of the color format manipulation code
  [ARM] pxafb: add palette format support for LCCR4_PAL_FOR_3
  [ARM] pxafb: add support for FBIOPAN_DISPLAY by dma braching
  [ARM] pxafb: allow pxafb_set_par() to start from arbitrary yoffset
  [ARM] pxafb: allow video memory size to be configurable
  [ARM] pxa: add document on the MFP design and how to use it
  [ARM] sa1100_wdt: don't assume CLOCK_TICK_RATE to be a constant
  [ARM] rtc-sa1100: don't assume CLOCK_TICK_RATE to be a constant
  [ARM] pxa/tavorevb: update board support (smartpanel LCD + keypad)
  [ARM] pxa: Update eseries defconfig
  [ARM] 5352/1: add w90p910-plat config file
  [ARM] s3c: S3C options should depend on PLAT_S3C
  [ARM] mv78xx0: implement GPIO and GPIO interrupt support
  [ARM] Kirkwood: implement GPIO and GPIO interrupt support
  [ARM] Orion: share GPIO IRQ handling code
  [ARM] Orion: share GPIO handling code
  [ARM] s3c: define __io using the typesafe version
  [ARM] S3C64XX: Ensure CPU_V6 is selected
  ...
2008-12-30 17:36:49 -08:00
Magnus Damm
a5616bd0f1 sh: sh_mobile i2c clock framework support
Add clock framework support to the sh_mobile i2c driver and
adjust the processor specific code accordingly.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:42:51 +09:00
Russell King
c613bbba6f Merge branch 'mxc-pu-imxfb' of git://pasiphae.extern.pengutronix.de/git/imx/linux-2.6 into devel 2008-12-17 20:04:45 +00:00
Ben Dooks
e355204ef7 i2c-omap: fix type of irq handler function
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: Ben Dooks <ben-linux@fluff.org>
2008-12-16 22:08:08 +00:00
Ben Dooks
5a93f42017 Merge branch 'i2c-for-ben' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 into i2c-next 2008-12-16 22:06:30 +00:00
Ben Dooks
e0d1ec9785 i2c-s3c2410: Change IRQ to be plain integer.
Change the code to use a plain integer as the holder
for the IRQ for the device and use platform_get_irq()
to find it.

This makes the code slightly neater, and easier to get
the IRQ number.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:27:28 +00:00
Ben Dooks
692acbd3a8 i2c-s3c2410: Allow more than one i2c-s3c2410 adapter
Newer SoCs such as the S3C6410 have 2 instances of this i2c
controller block in and thus require the ability to create
two seperate busses from this.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:26:46 +00:00
Ben Dooks
6a039cabba i2c-s3c2410: Remove default platform data.
The platform data should now always be present when the device
is initialised, so we can remove the default platform data in
the driver.

All the device initialisation points in the board specific code
should already have been changed to initialise this as necessary.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:26:06 +00:00
Ben Dooks
8be310a6de i2c-s3c2410: Use platform data for gpio configuration
Add a callback to set the gpio configuration for the
i2c device instead of a set include. This also allows
the remvoal of the machine gpio and hardware files.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:25:53 +00:00
Ben Dooks
3d0911bfe0 i2c-s3c2410: Fixup style problems from checkpatch.pl
Fixup the 36 warnings and errors generated from running
checkpatch.pl on the driver. The warnings are too numerous
to be listed here.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:24:16 +00:00
Ben Dooks
be44f01e8a i2c-s3c2410: fix check for being in suspend.
As noted by Julia Lawall <julia@diku.dk>, we can never
trigger the check for being in suspend due to the result
of !readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN
always being 0.

Add suspend/resume hooks to stop i2c transactions happening
until the driver has been resumed.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:19:53 +00:00
Mike Ditto
a804644a1a i2c-cpm: Detect and report NAK right away instead of timing out
Make the driver report an ENXIO error immediately upon NAK instead of
waiting for another interrupt and getting a timeout.

When reading from a device that is not present or declines to respond
to, e.g., a non-existent register address, CPM immediately reports a
NAK condition in the TxBD, but the driver kept waiting until a timeout,
which takes 1 second and causes an ugly console error message.

Signed-off-by: Mike Ditto <mditto@consentry.com>
Acked-by: Jochen Friedrich <jochen@scram.de>
[ben-linux@fluff.org: reordered description text]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 20:17:09 +00:00
Russell King
72aaf09fda Merge git://git.marvell.com/orion into devel 2008-12-13 09:12:51 +00:00
Harvey Harrison
2b895c3f35 i2c-highlander: Trivial endian casting fixes
Fixes sparse warnings:
drivers/i2c/busses/i2c-highlander.c:95:26: warning: incorrect type in argument 1 (different base types)
drivers/i2c/busses/i2c-highlander.c:95:26:    expected restricted __be16 const [usertype] *p
drivers/i2c/busses/i2c-highlander.c:95:26:    got unsigned short [usertype] *<noident>
drivers/i2c/busses/i2c-highlander.c:106:15: warning: incorrect type in assignment (different base types)
drivers/i2c/busses/i2c-highlander.c:106:15:    expected unsigned short [unsigned] [short] [usertype] <noident>
drivers/i2c/busses/i2c-highlander.c:106:15:    got restricted __be16

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-12-11 12:11:21 +01:00
Harvey Harrison
d9d38ca07d i2c-pmcmsp: Fix endianness misannotation
tmp is used as host-endian and is loaded from a be64, fix the cast and the
endian accessor used.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-12-11 12:11:20 +01:00
Russell King
fba670013d Merge branch 's3c-moves2' of git://aeryn.fluff.org.uk/bjdooks/linux into devel 2008-11-29 19:35:07 +00:00
Jean Delvare
7b964f7337 i2c-parport: Fix misplaced parport_release call
We shouldn't release the parallel port until we are actually done with
it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-11-28 15:24:39 +01:00
Russell King
e0d8b13ae1 [ARM] pxa: don't pass a consumer clock name for devices with unique clocks
Where devices only have one consumer, passing a consumer clock ID
has no real benefit.  Remove it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-27 12:38:23 +00:00
Kalle Jokiniemi
5043e9e737 i2c-omap: Enable I2C wakeups for 34xx
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: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:55 -08:00
Paul Walmsley
fdd07fe6f6 i2c-omap: reprogram OCP_SYSCONFIG register after reset
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: Paul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:55 -08:00
Paul Walmsley
9c76b878eb i2c-omap: convert 'rev1' flag to generic 'rev' u8
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: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:55 -08:00
Paul Walmsley
3831f15441 i2c-omap: fix I2C timeouts due to recursive omap_i2c_{un,}idle()
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: Paul 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: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:47 -08:00
Tony Lindgren
c1a473bde4 i2c-omap: Clean-up i2c-omap
Minor sparse, checkpatch and formatting clean-up. Also update copyrights.

Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:47 -08:00
Paul Walmsley
43469d8e2a i2c-omap: Don't compile in OMAP15xx I2C ISR for non-OMAP15xx builds
Skip compiling OMAP15xx I2C ISR for non-OMAP15xx builds.  Saves 400 bytes
of text for most OMAP builds.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:47 -08:00
Paul Walmsley
510be9c9ad i2c-omap: Mark init-only functions as __init
Mark functions called only at init time as __init.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:46 -08:00
Chandra shekhar
3d522fb41e i2c-omap: Add support for omap34xx
Add support for omap34xx

Signed-off-by: chandra shekhar <x0044955@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:46 -08:00
Nishanth Menon
b6ee52c399 i2c-omap: FIFO handling support and broken hw workaround for i2c-omap
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: Jason P Marini <jason.marini@gmail.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:46 -08:00
Syed Mohammed Khasim
4574eb6892 i2c-omap: Add high-speed support to omap-i2c
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: Syed Mohammed Khasim  <x0khasim@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:45 -08:00
Paul Walmsley
0cbbcffdf5 i2c-omap: Close suspected race between omap_i2c_idle() and omap_i2c_isr()
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: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:45 -08:00
Jarkko Nikula
b7af349b17 i2c-omap: Do not use interruptible wait call in omap_i2c_xfer_msg
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: Jarkko Nikula <jarkko.nikula@nokia.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2008-11-21 13:39:45 -08:00