Commit Graph

53 Commits

Author SHA1 Message Date
Bhumika Goyal 92d9d0dfb0 i2c: busses: constify i2c_algorithm structures
Declare i2c_algorithm structures as const as they are only stored in the
algo field of an i2c_adapter structure. This field is of type const, so
i2c_algorithm structures having this property can be made const too.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:06:52 +01:00
Wolfram Sang ea734404f3 i2c: don't print error when adding adapter fails
The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22 08:19:55 +02:00
Masanari Iida e952849a02 i2c: Fix typo in i2c-bfin-twi.c
This patch fix some typos found in a printk message and
MODULE_DESCRIPTION.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-07-31 13:32:31 +02:00
Wolfram Sang 1ecc4335eb i2c: busses: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:37 +02:00
Wolfram Sang aa5b775e0f i2c: i2c-bfin-twi: Drop class based scanning to improve bootup time
This driver has been flagged to drop class based instantiation. The removal
improves boot-up time and is unneeded for embedded controllers. Users have been
warned to switch for some time now, so we can actually do the removal. Keep the
DEPRECATED flag, so the core can inform users that the behaviour finally
changed now. After another transition period, this flag can go, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-07-16 22:59:58 +02:00
Sonic Zhang 0709dc9711 i2c: bfin: turn to Resource-managed API in probe function
No need to free managed resources any more.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-03 10:28:19 +02:00
Sonic Zhang 5029a22a45 i2c: bfin-twi: remove unnecessary Blackfin SSYNC from the driver
Put necessary SSYNC code into blackfin twi arch header. The generic TWI
driver should not contain any architecture specific code.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-09 08:41:18 +01:00
Sonic Zhang 45126da224 i2c: bfin-twi: move bits macros and structs in header from arch include to generic include
The ADI TWI peripheral is not binding to the Blackfin processor only.
The bits macros and structs should be put in the generic include header.
And update head file path in drivers accordingly.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-09 08:40:41 +01:00
Wolfram Sang 24ed93a6a3 i2c: i2c-bfin-twi: deprecate class based instantiation
Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
2014-03-05 17:16:53 +01:00
Jingoo Han 3c41aa7108 i2c: bfin-twi: Remove casting the return value which is a void pointer
Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:33 +02:00
Jingoo Han 6d4028c644 i2c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-19 19:46:30 +02:00
Jingoo Han 2fb9ac0cb4 i2c: i2c-bfin-twi: add CONFIG_PM_SLEEP to suspend/resume functions
Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following
build warning when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SIMPLE_DEV_PM_OPS are only used when
the CONFIG_PM_SLEEP is enabled.

drivers/i2c/busses/i2c-bfin-twi.c:585:12: warning: 'i2c_bfin_twi_suspend' defined but not used [-Wunused-function]
drivers/i2c/busses/i2c-bfin-twi.c:600:12: warning: 'i2c_bfin_twi_resume' defined but not used [-Wunused-function]

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 12:27:11 +02:00
Sonic Zhang 8419c8debd i2c: bfin-twi: Read and write the FIFO in loop
TWI transfer interrupts may be lost when system is heavily handling other
interrupts, while current transfer handler depends on each accurate interrupt
and misses some data in this case. Because there are 2 2-byte FIFOs in blackfin
TWI controller, the occurrence of the data loss can be reduced by reading till
the RX FIFO is empty and writing till the TX FIFO is full.

Reported-by: Bob Maris <mail@maris-ee.eu>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-12 20:39:07 +02:00
Doug Anderson 55827f4aa6 i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases.  This is just extra
cruft code that can be removed.

A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
  dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
  twice.
* I verified that there were no cases where xxx_get_drvdata() was
  being called in these drivers and checking for / relying on the NULL
  return value.

This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2013-02-22 00:25:50 +01:00
Sonic Zhang 90c16bbf57 i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
Depend on 1e92bf6d80

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:31 +02:00
Sonic Zhang f88aafe513 i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
Depend on commit cf93feb3a0

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:30 +02:00
Sonic Zhang c9d87edbcc i2c:i2c-bfin-twi: include twi head file
TWI bit mask macros are moved to twi head file.
Depend on commit 61c16b5c74

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:29 +02:00
Sonic Zhang 28a377c79a i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
Current driver was developed based on BF537 0.2 HRM. In high system load, BUFRDERR error
interrupt may be raised if XMTSERV interrupt of last TX byte is not served in time
(set RSTART bit), which breaks restart tranfer as expected.

"Buffer Read Error (BUFRDERR)" description in Blackfin HRM only applys to BF537
rev. < 0.3. In later rev. and later announced Blackfin chips, such as BF527 and
BF548, a new TWI master feature "Clock Stretching" is added into the TWI controller,
BUFRDERR interrupt is not triggered after TX FIFO is empty.

This patch sets RSTART bit at the beginning of the first transfer. The SCL and SDA
is hold till XMTSERV interrupt of last TX byte is served. Restart transfer is not broken
in high system load.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>

[wsa: fixed spaces around operators]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:37:04 +02:00
Sonic Zhang 2ee74eb95c i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
In order to mark I2C transfer fail when MEN bit in I2C controller is
reset unexpectedly in MCOMP interrupt, interrupt status bits XMTSERV or
RCVSERV should be checked.

Master Transfer Complete (MCOMP).
[1] The initiated master transfer has completed. In the absence of a
repeat start, the bus has been released.
[0] The completion of a transfer has not been detected.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>

[wsa: fixed spaces around operators and typo in commit message]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:36:07 +02:00
Sonic Zhang a25733d6f6 i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
Some fault i2c device may hold the sda/scl line and cause i2c driver
wait in the BUS busy loop. The I2C framework already retry the
transfer loop before timeout. Return -EAGAIN instead of pull BUSBUSY
in the other loop.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00
Sonic Zhang a20a64d226 i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
For transfer counts > 255 bytes i2c-bfin-twi sets the data
transfer counter DCNT to 0xFF indicating unlimited transfers.
It then uses a flag iface->manual_stop to manually issue the STOP
condition, once the required amount of bytes are received.

We found that on I2C receive operation issuing the STOP condition
together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be
constantly driven low.

This patch stops receiving operation immediately in last rx interrupt.
This patch also wakes up waiting process when transfer completes.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00
Michael Hennerich 925594e035 i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
For transfer counts > 255 bytes i2c-bfin-twi sets the data
transfer counter DCNT to 0xFF indicating unlimited transfers.
It then uses a flag iface->manual_stop to manually issue the STOP
condition, once the required amount of bytes are received.

We found that on I2C receive operation issuing the STOP condition
together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be
constantly driven low.

Temporary workaround until further investigation:
Discard the RCV FIFO before issuing the STOP condition.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-13 08:27:31 +02:00
Rafael J. Wysocki 85777ad264 i2c-bfin-twi: Use struct dev_pm_ops for power management
Make the Blackfin On-Chip Two Wire Interface driver define its PM
callbacks through a struct dev_pm_ops object rather than by using
legacy PM hooks in struct platform_driver.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-12 12:04:38 +02:00
Yong Zhang 4311051c35 i2c: irq: Remove IRQF_DISABLED
Since commit [c58543c8: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29 09:55:45 +01:00
Sonic Zhang 4a65163e3b i2c-bfin-twi: abort transfer is MEM bit is reset unexpectedly
Sometimes, the first I2C transmit interrupt is not serviced in time (like
when higher priority interrupts take too long).  Since the RESTART bit is
not set before the next I2C clock, when the TWI handler is finally called,
the I2C session is aborted (MEM bit is reset) and both SMITSERV and MCOMP
int status bits are set.

So when this happens, abort the transfer.

Reported-by: Isabelle Leonardi <i.leonardi@detracom.fr>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-06-27 23:06:48 +01:00
Michael Hennerich 74f56c4ad4 i2c-bfin-twi: move setup to the earlier subsys initcall
Some systems using this bus sometimes have very basic devices such as
regulators on the bus, so the I2C bus master needs to be loaded early.
This also matches the behavior of many other I2C bus master drivers.
Therefore initialize via subsys_initcall().

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-01-12 22:23:08 +00:00
Michael Hennerich 540ac5553e i2c-bfin-twi: handle faulty slave devices better
Faulty slave devices might drive SDA low after a transfer finishes.  So,
when this scenario is detected, have the master generate up to 9 extra
clocks until the SDA is properly released.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-01-12 22:23:05 +00:00
Sonic Zhang f0ac131a21 i2c-bfin-twi: return completion in interrupt for smbus quick transfers
A smbus quick transfer has no data after the address byte.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +01:00
Sonic Zhang be2f80f0a3 i2c-bfin-twi: remove redundant retry
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +01:00
Sonic Zhang 5481d0753e i2c-bfin-twi: fix lost interrupts at high speeds
i2c event of next read/write byte may trigger before current int state
is cleared in the interrupt handler. So, this should be done at the
beginning of interrupt handler to avoid losing new i2c events.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +01:00
Michael Hennerich 5cfafc18f3 i2c-bfin-twi: add debug output for error status
Add some debug() code to decode the error register.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +01:00
Sonic Zhang dd7319a528 i2c-bfin-twi: integrate timeout timer with completion interface
There isn't much point in managing our own custom timeout timer when the
completion interface already includes support for it.  This makes the
resulting code much simpler and robust.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 00:18:58 +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
Sonic Zhang ac07fb4dc1 i2c-bfin-twi: fix CLKDIV calculation
Calculation of the CLKDIV speed setting should be done using base 10 math
rather than base 2.  We also avoid exceeding the spec due to integer
truncation and a 50% duty cycle.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-24 01:24:48 +00:00
Linus Walleij c6ffddea36 i2c: Use resource_size macro
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: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-16 22:42:16 +01:00
Mike Frysinger 6df263cf2e i2c-bfin-twi: pull in io.h for ioremap()
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: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-16 22:42:15 +01:00
Michael Hennerich e0cd2dd5dd i2c: Blackfin TWI: implement I2C_FUNC_SMBUS_I2C_BLOCK functionality
Some drivers need i2c_smbus_read_i2c_block_data() functionality, so add
support for it to the Blackfin I2C bus driver.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
[ben-linux@fluff.org: shortened subject]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-13 10:39:25 +01:00
Frank Shew 94327d009e i2c: Blackfin TWI: fix transfer errors with repeat start
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: Frank Shew <fshew@geometrics.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shorted subject]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-13 10:39:25 +01:00
Sonic Zhang 57a8f32eaf i2c: Blackfin TWI: fix REPEAT START mode doesn't repeat
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: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shorted subject]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-13 10:39:25 +01:00
Michael Hennerich 9528d1c7a5 i2c: Blackfin TWI: make sure we don't end up with a CLKDIV=0
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: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
[ben-linux@fluff.org: shortened subject line]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-13 10:39:25 +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 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
Michael Hennerich 958585f58f i2c: Blackfin I2C Driver: Functional power management support
PM_SUSPEND_MEM: Blackfin does not maintain register state through
Hibernate. Save and restore peripheral base initialization during
PM transitions.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28 12:41:03 +01:00
Kay Sievers add8eda7f2 i2c: Fix platform driver hotplug/coldplug
Since 43cc71eed1, the platform
modalias is prefixed with "platform:". Add MODULE_ALIAS() to the
hotpluggable I2C platform drivers, to allow module auto loading.

[ db: add some more drivers ]

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:49 +02:00
Hans Schillstrom afc13b765e i2c-bfin-twi: Fix mismatch in add timer and delete timer
Move init_completion to just before i2c transfer.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3385

Signed-off-by: Hans Schillstrom <hans.schillstrom@shlsys.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:48 +02:00
Mike Frysinger bd584996b0 i2c-bfin-twi: Use simpler comment headers and strip out information that is maintained in the scm's log
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:48 +02:00
Bryan Wu fa6ad22271 i2c-bfin-twi: Cleanup driver descriptions, versions and some module useful information
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:48 +02:00
Bryan Wu 74d362e0b3 i2c-bfin-twi: Add missing pin mux operation
Blackfin TWI controller hardware pin should be requested from GPIO port controller
Before BF54x, there is no need to do this. But as long as BF54x and BF52x
are supported by this generic driver, the missing pin mux operation should be
added.

Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:48 +02:00
Bryan Wu aa3d020917 i2c-bfin-twi: Add platform_resource interface to support multi-port TWI controllers
- Dynamic alloc the resource of TWI driver data according to board information
 - TWI register read/write accessor based on dynamic regs_base
 - Support TWI0/TWI1 for BF54x

Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:48 +02:00
Sonic Zhang 4dd39bb12f i2c-bfin-twi: Add repeat start feature to avoid break of a bundle of i2c master xfer operation
- Create a new mode TWI_I2C_MODE_REPEAT.
 - No change to smbus operation.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22 22:16:47 +02:00