When a process tries to read/write a disconnected i2c device, it receives a signal (e.g. ctrl-c) and the kernel gets stuck.

BUG: soft lockup - CPU#0 stuck for 61s! [I2CEEpromTest:392]
NIP: c01628f8 LR: c01628f0 CTR: c00177cc
REGS: c39abd70 TRAP: 0901   Not tainted  (2.6.25.7-alcore)
MSR: 00009032 <EE,ME,IR,DR>  CR: 42042048  XER: 20000000
TASK = c3889bd0[392] 'I2CEEpromTest' THREAD: c39aa000
GPR00: 00009000 c39abe20 c3889bd0 c39075c8 c39abe28 00000001 00000000 00000001
GPR08: c3889bd0 c39075c8 00009032 c39abe34 00002437
NIP [c01628f8] cpm_i2c_xfer+0x5fc/0x6d0
LR [c01628f0] cpm_i2c_xfer+0x5f4/0x6d0
Call Trace:
[c39abe20] [c0162924] cpm_i2c_xfer+0x628/0x6d0 (unreliable)
[c39abe90] [c015f6a0] i2c_transfer+0x88/0xb4
[c39abeb0] [c0160164] i2c_master_recv+0x48/0x6c
[c39abed0] [c01618dc] i2cdev_read+0x50/0xe4
[c39abef0] [c0068b24] vfs_read+0xc4/0x108
[c39abf10] [c0068f4c] sys_read+0x4c/0x90
[c39abf40] [c000d348] ret_from_syscall+0x0/0x38
Instruction dump:
3bc00064 92610010 3bf201c8 92810014 3b61

This happen because though the wait_event_interruptible_timeout takes the
signals into account, the driver does not handle them.
We propose to change the wait_event_interruptible_timeout with
wait_event_timeout, leaving the signals to be handled in other points
on the upper layers.
Signed-off-by: NBruno Morelli <bruno@evidence.eu.com>
Signed-off-by: NMichael Trimarchi <michael@evidence.eu.com>
Acked-by: NJochen Friedrich <jochen@scram.de>
[ben-linux@fluff.org: fix title for patch]
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>

So far, MPC512x used mpc512x_find_ips_freq() to get the bus frequency,
while MPC52xx used mpc52xx_find_ipb_freq().  Despite the different
clock names (IPS vs. IPB) the code was identical.

Use common code for both processor families.
Signed-off-by: NWolfgang Denk <wd@denx.de>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

This makes the stu300 driver for the ST Micro ST DDC I2C bus
driver depend on MACH_U300, new platforms reusing this I2C
driver will need to add in a similar dependency.
Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com>
[ben-linux@fluff.org: re-aranged subject line]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Change the usage of res->end-res->start to resource_size(), missed
by the last patch to change this.
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>

This adds support for the ST Microelectronics DDC I2C bus
driver. This bus is used in the U300 architecture recently
added to RMK:s ARM tree.
Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com>
Reviewed-by: NBen Dooks <ben-linux@fluff.org>
Reviewed-by: NJean Delvare <khali@linus-fr.org>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Rather than relying on some of the headers implicitly pulling in io.h,
pull it in explicitly our self for ioremap() and friends.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The south bridge of the VIA VX855 chipset has a different PCI Device ID
so i2c-viapro.c needs to be updated with this.
Signed-off-by: NHarald Welte <HaraldWelte@viatech.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

There's no point in giving the I2C bus of Voodoo3 adapters a class
value, there's no video chip driver checking for it anymore. If
support is ever needed, the video device should be instantiated
explicitly rather than probed.

To the best of my knowledge the only video chip that can be found on
these boards is a BT869 video encoder, for which no support exists
currently.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NKrzysztof Helt <krzysztof.h1@wp.pl>

There is sometimes a need for the ocores driver to add devices to the
bus when installed.

i2c_register_board_info can not always be used, because the I2C devices
 are not known at an early state, they could for instance be connected
 on a I2C bus on a PCI device which has the Open Cores IP.

i2c_new_device can not be used in all cases either since the resulting
bus nummer might be unknown.

The solution is the pass a list of I2C devices in the platform data to
the Open Cores driver. This is useful for MFD drivers.
Signed-off-by: NRichard Röjfors <richard.rojfors.ext@mocean-labs.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Change to using platform id table to match either of the two supported
platform device names in the driver. This simplifies the driver init and
exit code

Note, log messages will now be prefixed with 's3c-i2c' instead of the
driver name, so output will be of the form of:

s3c-i2c s3c2440-i2c.0: slave address 0x10
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>

Some drivers need i2c_smbus_read_i2c_block_data() functionality, so add
support for it to the Blackfin I2C bus driver.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
[ben-linux@fluff.org: shortened subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

We have a custom BF537 board with an I2C RTC (MAX DS3231) running
uclinux 2007R1 for some time. Recently during migration to 2008R1.5-RC3
we losted access to the RTC. The RTC driver calls 'i2c_transfer()' which
in turns calls 'bfin_twi_master_xfer()' in i2c-bfin-twi.c.

Compared with 2007R1, it looks like the 2008R1.5 version of i2c-bin-twi.c
has a new mode 'TWI_I2C-MODE_REPEAT' which corresponds to the Repeat Start
Condition described in the HRM. However, according to the HRM, at XMIT or
RECV interrupt and when the data count is 0, not only is the RESTART bit
supposed to be set, but MDIR must also be set if the next operation is a
receive sequence, and cleared if not. Currently there is no code that looks
at the I2C_M_RD bit in the flag from the next cur_msg and set/clear the MDIR
flag accordingly at the same time that the RSTART bit is set. Instead, MDIR
is set or cleared (by OR'ing with 0?) after the RESTART bit has been cleared
during handling of MCOMP interrupt.

It appears that this is causing our failure with reading the RTC, as a
quick patch to set/clear MDIR when RESTART is set seem to solve our problem.
Signed-off-by: NFrank Shew <fshew@geometrics.com>
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shorted subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Avoid rewrite TWI MASTER_CTL reg when issue next message
In i2c repeat transfer mode, byte count of next message should be filled
into part of the TWI MASTER_CTL reg when interrupt MCOMP of last
message transfer is triggered. But, other bits in this reg should
not be touched.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shorted subject]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Make sure we don't end up with an invalid CLKDIV=0 in case someone
specifies 20kHz SCL or less (5 * 1024 / 20 = 0x100).
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shortened subject line]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Signed-off-by: NPaul Shen <paul.shen@marvell.com>
Signed-off-by: NEric Miao <eric.miao@marvell.com>

Signed-off-by: NEric Miao <eric.miao@marvell.com>

The i2c-ibm_iic driver printed messages in an odd order that seemed
to list devices before the driver was probed.

Here is an example:

at24 0-0052: 512 byte 24c04 EEPROM (writable)
ibm-iic ef600700.i2c: using standard (100 kHz) mode
ad7414 0-004a: chip found

This changes the order to print the i2c driver message before scanning
for devices so that the logs show the driver, then the devices. 
Signed-off-by: NSean MacLennan <smaclennan@pikatech.com>
Acked-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

For consistenct naming, and to allow us to fix up some confusion in the
SH-Mobile clock framework, amongst other places.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Recent DMA changes result in a BUG() when NULL is passed to
dma_alloc_coherent in place of a device.
Signed-off-by: NMark Ware <mware@elphinstone.net>
[ben-linux@fluff.org: fix patch moves]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This controller is also present on the S3C64xx series processors so
enable the driver in Kconfig for those platforms.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The clock setting did not work for the MPC52xx due to a stupid bug.
Furthermore, the dev info output "clock=0" for old device trees was
misleading. This patch fixes both issues.
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

with while (timeout++ < MAX_TIMEOUT); timeout reaches MAX_TIMEOUT + 1
after the loop, so the tests below are off by one.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

With `while (timeout--)' timeout reaches -1 after the loop, so the tests
below are off by one.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Support for I2C/DDC was recently added to the tdfxfb driver, which
means that the i2c-voodoo3 driver can be deprecated.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>

'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: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: NDarius Augulis <augulis.darius@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Support for the s6000 on-chip i2c controller.
Signed-off-by: NOskar Schirmer <os@emlix.com>
Signed-off-by: NDaniel Glöckner <dg@emlix.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This patch makes the I2C bus speed configurable by using the I2C node
property "clock-frequency". If the property is not defined, the old
fixed clock settings will be used for backward comptibility.

The generic I2C clock properties, especially the CPU-specific source
clock pre-scaler are defined via the OF match table:

  static const struct of_device_id mpc_i2c_of_match[] = {
	...
	{.compatible = "fsl,mpc8543-i2c",
	 .data = &(struct fsl_i2c_match_data) {
			.setclock = mpc_i2c_setclock_8xxx,
			.prescaler = 2,
		},
	},

The "data" field defines the relevant I2C setclock function and the
relevant pre-scaler for the I2C source clock frequency.

It uses arch-specific tables and functions to determine resonable
Freqency Divider Register (fdr) values for MPC83xx, MPC85xx, MPC86xx,
MPC5200 and MPC5200B.

The i2c->flags field and the corresponding FSL_I2C_DEV_* definitions
have been removed as they are obsolete.
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This patch used the dev_dbg, dev_err, etc. functions for debug
and error output instead of printk and pr_debug.
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Fix errors reported by checkpatch (indention, long lines, trailing
white space, etc.).
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Signed-off-by: NDarius Augulis <augulis.darius@gmail.com>
[ben-linux@fluff.org: fix minor patch fault in remove]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This is required in order to ensure that core system devices such as
voltage regulators attached via I2C are avaiable early in boot.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The platform data for the i2c-s3c2410 driver used to allow a min,
max and desired frequency for the I2C bus. This patch reduces it
to simply a desired frequency ceiling and corrects all the uses
of the platform data appropriately.

This means, for example, that on a system with a 66MHz fclk, a
request for 100KHz will achieve 65KHz which is safe and
acceptable, rather than 378KHz which it would have achieved
without this change.
Signed-off-by: NSimtec Linux Team <linux@simtec.co.uk>
Signed-off-by: NDaniel Silverstone <dsilvers@simtec.co.uk>
[ben-linux@fluff.org: tidy subject and description]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The sda_delay field should be specified in ns, not in clock ticks
as when using cpufreq we could be changing the bus rate.
Signed-off-by: NBen Dooks <ben@simtec.co.uk>

Implementation of I2C Adapter/Algorithm Driver for I2C Bus integrated
in Freescale's i.MX/MXC processors.
Signed-off-by: NDarius Augulis <augulis.darius@gmail.com>
Tested-by: NSascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Detect various FSC hwmon IC's based on DMI tables and then let
the i2c-i801 driver instantiate the i2c client devices. Note that
some of the info in the added table is indentical for all rows, still
this is kept in the table to keep the code general and thus (hopefully)
easily extensible in the future.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Add support for the Broadcom HT1100 LD chipset (SMBus function.)
Signed-off-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>