Commit Graph

120 Commits

Author SHA1 Message Date
Wolfram Sang cc21d0b4b6 i2c: rcar: init new messages in irq
Setting up new messages was done in process context while handling a
message was in interrupt context. Because of the HW design, this IP core
is sensitive to timing, so the context switches were too expensive. Move
this setup to interrupt context as well.

In my test setup, this fixed the occasional 'data byte sent twice' issue
which a number of people have seen. It also fixes to send REP_START
after a read message which was wrongly send as a STOP + START sequence
before.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:21:29 +01:00
Wolfram Sang b9d0684c79 i2c: rcar: refactor setup of a msg
We want to reuse this function later.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:21:07 +01:00
Wolfram Sang ff2316b87a i2c: rcar: remove spinlock
After making sure to reinit the HW and clear interrupts in the timeout
case, we know that interrupts are always disabled in the sections
protected by the spinlock. Thus, we can simply remove it which is a
preparation for further refactoring. While here, rename the timeout
variable to time_left which is way more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:20:46 +01:00
Wolfram Sang 90f779e565 i2c: rcar: remove unused IOERROR state
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:20:25 +01:00
Wolfram Sang 2c78cdc1c0 i2c: rcar: rework hw init
We don't need to init HW before every transfer since we know the HW
state then. HW init at probe time is enough. While here, add setting the
clock register which belongs to init HW. Also, set MDBS bit since not
setting it is prohibited according to the manual.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:20:04 +01:00
Wolfram Sang e43e0df13f i2c: rcar: make sure clocks are on when doing clock calculation
When calculating the bus speed, the clock should be on, of course. Most
bootloaders left them on, so this went unnoticed so far.

Move the ioremapping out of this clock-enabled-block and prepare for
adding hw initialization there, too.

Reported-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30 14:19:42 +01:00
Linus Torvalds d55fc37856 Merge branch 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - New drivers: UniPhier (with and without FIFO)

 - some drivers got some bigger rework: ismt, designware, img-scb (rcar
   had to be reverted because issues were showing up just lately)

 - ACPI: reworked the device scanning and added support for muxes

... and quite a lot of driver bugfixes and cleanups this time.  All
files touched outside of the i2c realm have proper acks.

* 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
  i2c: rcar: Revert the latest refactoring series
  i2c: pnx: remove superfluous assignment
  MAINTAINERS: i2c: drop i2c-pnx maintainer
  MAINTAINERS: i2c: mark also subdirectories as maintained
  i2c: cadence: enable driver for ARM64
  i2c: i801: Document Intel DNV and Broxton
  i2c: at91: manage unexpected RXRDY flag when starting a transfer
  i2c: pnx: Use setup_timer instead of open coding it
  i2c: add ACPI support for I2C mux ports
  acpi: add acpi_preset_companion() stub
  i2c: pxa: Add support for pxa910/988 & new configuration features
  i2c: au1550: Convert to devm_kzalloc and devm_ioremap_resource
  i2c-dev: Fix I2C_SLAVE ioctl comment
  i2c-dev: Fix typo in ioctl name reference
  i2c: sirf: tune the divider to make i2c bus freq more accurate
  i2c: imx: Use -ENXIO as error in the NACK case
  i2c: i801: Add support for Intel Broxton
  i2c: i801: Add support for Intel DNV
  i2c: mediatek: add i2c resume support
  i2c: imx: implement bus recovery
  ...
2015-11-10 11:58:25 -08:00
Wolfram Sang 75ecc64ef5 i2c: rcar: Revert the latest refactoring series
This whole series caused sometimes timeouts and even OOPSes on some
r8a7791 Koelsch boards. We need to understand and fix those first.

Revert "i2c: rcar: clean up after refactoring"
Revert "i2c: rcar: revoke START request early"
Revert "i2c: rcar: check master irqs before slave irqs"
Revert "i2c: rcar: don't issue stop when HW does it automatically"
Revert "i2c: rcar: init new messages in irq"
Revert "i2c: rcar: refactor setup of a msg"
Revert "i2c: rcar: remove spinlock"
Revert "i2c: rcar: remove unused IOERROR state"
Revert "i2c: rcar: rework hw init"

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-30 12:40:46 +01:00
Geert Uytterhoeven c6f1891323 i2c: rcar: Remove obsolete platform data support
Since commit 4baadb9e05 ("ARM: shmobile: r8a7778: remove obsolete
setup code"), Renesas R-Car SoCs are only supported in generic DT-only
ARM multi-platform builds.  The driver doesn't need to use platform data
anymore, hence remove platform data configuration.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[wsa: removed now unused ret value and cast to proper enum type]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-20 18:10:25 +02:00
Wolfram Sang e7db0d34b3 i2c: rcar: add support for r8a7795 (R-Car H3)
Enable the I2C core for this SoC. I add a new type because this version
has new features (e.g. DMA) which will be added somewhen later.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-20 18:03:07 +02:00
Wolfram Sang 4f7effddf4 i2c: rcar: enable RuntimePM before registering to the core
The core may register clients attached to this master which may use
funtionality from the master. So, RuntimePM must be enabled before, otherwise
this will fail. While here, move drvdata, too.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2015-10-15 14:25:56 +02:00
Wolfram Sang 708ca40841 i2c: rcar: clean up after refactoring
Update the comments to match current behaviour. Shorten some comments.
Update copyrights.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:32:14 +01:00
Wolfram Sang e5a7effa09 i2c: rcar: revoke START request early
If we don't clear START generation as soon as possible, it may cause
another message to be generated. To keep the race window as small as
possible, we clear it right at the beginning of the interrupt. We don't
need checking since we always want to stop START and STOP generation on
the next occasion after we started it.

This patch improves the situation but sadly does not completely fix it.
It is still to be researched if we can do better given this HW design.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:31:54 +01:00
Wolfram Sang 2151ba7584 i2c: rcar: check master irqs before slave irqs
Due to broken HW design, master IRQs are more timing critical, so give
them precedence over slave IRQ.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:31:34 +01:00
Wolfram Sang 315a1736a2 i2c: rcar: don't issue stop when HW does it automatically
The manual says (55.4.8.6) that HW does automatically send STOP after
NACK was received. My measuerments confirm that.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:31:13 +01:00
Wolfram Sang 2bc3c5a863 i2c: rcar: init new messages in irq
Setting up new messages was done in process context while handling a
message was in interrupt context. Because of the HW design, this IP core
is sensitive to timing, so the context switches were too expensive. Move
this setup to interrupt context as well.

In my test setup, this fixed the occasional 'data byte sent twice' issue
which a number of people have seen. It also fixes to send REP_START
after a read message which was wrongly send as a STOP + START sequence
before.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:30:53 +01:00
Wolfram Sang 344beeb23b i2c: rcar: refactor setup of a msg
We want to reuse this function later.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:30:32 +01:00
Wolfram Sang 738206dec9 i2c: rcar: remove spinlock
We make sure to reinit the HW in the timeout case; then we know that
interrupts are always disabled in the sections protected by the
spinlock. Thus, we can simply remove it which is a preparation for
further refactoring. While here, rename the timeout variable to
time_left which is way more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:30:12 +01:00
Wolfram Sang 59daef909d i2c: rcar: remove unused IOERROR state
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:29:51 +01:00
Wolfram Sang 93c659d820 i2c: rcar: rework hw init
We don't need to init HW before every transfer since we know the HW
state then. HW init at probe time is enough. While here, add setting the
clock register which belongs to init HW. Also, set MDBS bit since not
setting it is prohibited according to the manual.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-09 22:29:28 +01:00
Wolfram Sang b6763d0da5 i2c: rcar: use proper type for timeout
wait_event_timeout returns long, not int.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-23 19:50:20 +02:00
Wolfram Sang efd2c6118e i2c: rcar: use adapter default for timeout
5 seconds is a very large timeout, and it is hardcoded. Use the default
timeout from 'struct adapter' which is 1 second. It can also be modified
from userspace for specific workloads via i2c-dev.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-23 19:50:10 +02:00
Wolfram Sang 1fb2ad9565 i2c: rcar: report slave capabilities to users
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-01 08:07:14 +09:00
Krzysztof Kozlowski e9a02a3d89 i2c: constify platform_device_id
The platform_device_id is not modified by these drivers and core uses it
as const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-05-12 18:27:48 +02:00
Wolfram Sang 5b77d162a3 i2c: slave: rework the slave API
After more discussion, brave users, and additional datasheet evaluation,
some API updates for the new I2C slave framework became imminent. The
slave events now get some easier to understand naming. Also, the event
handling has been simplified to only need a single call to the slave
callback when an action by the backend is required.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-27 16:53:38 +01:00
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Wolfram Sang de20d1857d i2c: rcar: add slave support
The first I2C slave provider using the new generic interface.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11 22:25:55 +01:00
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 22762ccb0e i2c: rcar: remove sign-compare flaw
gcc rightfully says:

drivers/i2c/busses/i2c-rcar.c:198:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:43:25 +02:00
Sergei Shtylyov aa5beaf625 i2c: rcar: check for no IRQ in rcar_i2c_irq()
Check if the ICMSR register (masked with the ICMIER register) evaluates to 0  in
the driver's interrupt handler and return IRQ_NONE in that case, like many other
drivers do.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:41:18 +02:00
Sergei Shtylyov 7c7117ffe0 i2c: rcar: make rcar_i2c_prepare_msg() *void*
rcar_i2c_prepare_msg() always returns 0, so we can make this function return
*void* and thus remove the result check in rcar_i2c_master_xfer().

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:41:17 +02:00
Sergei Shtylyov c30d7662d8 i2c: rcar: simplify check for last message
rcar_i2c_master_xfer() needlessly compares the message pointers (using indirect
addressing) in order to detect the last I2C message, while it's enough to only
compare the message indexes.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:41:17 +02:00
Sergei Shtylyov 938916fbb8 i2c: rcar: fix RCAR_IRQ_ACK_{RECV|SEND}
Bits 8-31 of all registers reflect the value of bits 0-7 on reads and should be
0 on writes, according to the manuals. RCAR_IRQ_ACK_{RECV|SEND} macros have all
1's in bits 8-31, thus going against the manuals, so fix them.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-20 11:56:20 +02:00
Sergei Shtylyov 91bfe2989a Revert "i2c: rcar: remove spinlock"
This reverts commit 150b8be3cd.

The I2C core's per-adapter locks can't protect from IRQs, so the driver still
needs a spinlock to protect the register accesses.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-04 19:59:42 +02:00
Sergei Shtylyov dd318b0df2 i2c: rcar: fix MNR interrupt handling
Sometimes the MNR and MST interrupts happen simultaneously  (stop  automatically
follows NACK, according to the manuals) and in such case the ID_NACK flag  isn't
set since the MST interrupt handling precedes MNR and all interrupts are cleared
and disabled then, so that MNR interrupt is never noticed -- this causes NACK'ed
transfers to be falsely reported as successful. Exchanging MNR and  MST handlers
fixes this issue, however the MNR bit  somehow  gets set again even after  being
explicitly cleared, so I decided to completely suppress handling of all disabled
interrupts (which is a good thing anyway)...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-02 12:28:15 +02:00
Wolfram Sang 929e3aba51 i2c: i2c-rcar: 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.
While we are here, remove the indentation for the array setup because
such things always break after some time.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-07-16 23:00:04 +02:00
Jingoo Han 46797a2adb i2c: remove unnecessary OOM messages
The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message. For example,
k.alloc and v.alloc failures use dump_stack().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-02 19:24:33 +02:00
Wolfram Sang 3d99beabf1 i2c: rcar: update copyright and license information
Make clear that the driver is GPL v2 only. Remove FSF address. Remove
filename in comment. Update copyright information.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:23:00 +02:00
Wolfram Sang 51371cdc86 i2c: rcar: janitorial cleanup after refactoring
Remove some obvious comments, remove some superfluous debug output (the
error code carries the same information), some white space fixing...

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:55 +02:00
Wolfram Sang 3e3aabac44 i2c: rcar: reuse status bits as enable bits
Status register and enable register are identical regarding their
layout. Use the bit definitions for both.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:51 +02:00
Wolfram Sang 150b8be3cd i2c: rcar: remove spinlock
The i2c core has per-adapter locks, so no need to protect again.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:47 +02:00
Wolfram Sang 3c95de6744 i2c: rcar: refactor status bit handling
The old macros made it harder to see what was actually happening.
Replace them with something more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:42 +02:00
Wolfram Sang 386babf8e2 i2c: rcar: refactor setting up msg
Setting up a read or write message is similar enough to be done in one
function. Also, move a helper function into the new function since it is
only used here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:38 +02:00
Wolfram Sang 3f7de22eb2 i2c: rcar: check bus free before first message
We should always check if the bus is free, independently if it is a read
or write. It should be done before the first message, though. After
that, we ourselves keep the bus busy. Remove a 'ret' assignment which
only silenced a build warning.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:34 +02:00
Wolfram Sang f2382249b2 i2c: rcar: refactor irq state machine
Remove the seperate functions and use designated constants. As readable
but less overhead. Actually, this is even more readable since the old
function used a mix of "=" and "|=".

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:29 +02:00
Wolfram Sang 4f443a8a61 i2c: rcar: refactor bus state machine
Remove the seperate functions and use designated constants. As readable
but less overhead.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:25 +02:00
Wolfram Sang 93e953d378 i2c: rcar: no need to store irq number
We use devm, so irq number is only needed during probe.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:20 +02:00
Wolfram Sang 1c176d534f i2c: rcar: not everything needs to be a function
Very basic operations, just called once, can also go to the caller.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:22:13 +02:00
Wolfram Sang 819a39510e i2c: rcar: add compatibles for additional SoC
Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-01 22:21:59 +02:00
Wolfram Sang d7653964c5 i2c: rcar: bail out on zero length transfers
This hardware does not support zero length transfers. Instead, the
driver does one (random) byte transfers currently with undefined results
for the slaves. We now bail out.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-05-14 18:59:57 +02:00
Wolfram Sang 96c4b6bb5d i2c: i2c-rcar: 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>
2014-03-05 17:17:15 +01:00
Wolfram Sang e893645568 i2c: rcar: add compatible entry for r8a7791
While we are here, also brush up the devicetree binding documentation.
The example was an inappropriate copy from the sh_mobile driver.

Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-02-26 23:11:55 +01:00
Ben Dooks 6ff4b10516 i2c: rcar: fix NACK error code
The response to a bus NACK is to return -ENXIO instead of the
-EREMOTEIO being currently returned by the driver.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-26 22:48:36 +01:00
Ben Dooks bc8120f17a i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
The current i2c-rcar driver does clk_get() without a corresponding
clk_put(). Add the clk to the driver private data and then get it
with the devm functions so that it is released when the driver is
unbound.

Note, we do not call clk_prepare_enable() at this point due to the
very possible magic that is being done by the pm_runtime system
underneath the driver.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-26 22:48:34 +01:00
Ben Dooks 770540f029 i2c: rcar: do not print error if device nacks transfer
The i2c-rcar driver currently prints an error message if the master_xfer
callback fails. However if the bus is being probed then lots of NAKs
will be generated, causing the output of a number of errors printed.

To solve this, disable the print if the error is not -EREMOTEIO.

An example of running i2cdetect:

10: i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- 12 i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15
-- i2c-rcar e6530000.i2c: error -121 : 15

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-26 22:48:29 +01:00
Paul Gortmaker 21d0b7c0fa i2c: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-24 18:24:31 +01:00
Kuninori Morimoto 043a3f113c i2c: rcar: fixup rcar type naming
b720423a26
(i2c: rcar: add rcar-H2 support)
added R-Car H2 support on i2c-rcar.

The R-Car I2C type is based on SoC generation
(Gen1 = E1/M1/H1, Gen2 = E2/M2/H2),
but added naming was H1/H2 instead of Gen1/Gen2.
Gen1/Gen2 is better naming on this driver.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-11-01 14:10:00 +01:00
Guennadi Liakhovetski 991e7ecf1f i2c: rcar: use per-device clock
Using the same clock for all device instances is non-portable and obtaining
clock references by an ID without using a device pointer is discouraged.
This is also not needed, because on platforms, where this driver is used,
suitable clocks are available for the I2C controllers, that are children of
the peripheral clock and just pass its rate 1-to-1 to controllers. This
patch switches the driver to obtain references to correct clocks.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:32 +02:00
Guennadi Liakhovetski 330c824a49 i2c: rcar: fix clk_get() error handling
When clk_get() fails, it returns an error code, not a NULL. This patch
fixes such an error handling bug.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:32 +02:00
Guennadi Liakhovetski 7679c0e191 i2c: rcar: add Device Tree support
This patch adds Device Tree support to the i2c-rcar driver and respective
documentation.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:32 +02:00
Guennadi Liakhovetski 8d0494037b i2c: rcar: get clock rate only once and simplify calculation
There is no need to repeatedly query clock frequency, where it is not
expected to change. The complete loop can also trivially be replaced with
a simple division. A further loop below the one, being simplified, could
also be replaced, but that would get more complicated.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:32 +02:00
Guennadi Liakhovetski 14d32f1794 i2c: rcar: (cosmetic) remove superfluous parenthesis
A recent patch added even more superfluous parenthesis to those, which
already were there. Remove them again.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-30 06:02:31 +02:00
Nguyen Viet Dung b720423a26 i2c: rcar: add rcar-H2 support
This patch modify I2C driver of rcar-H1 to usable on both rcar-H1 and rcar-H2.

Signed-off-by: Nguyen Viet Dung <nv-dung@jinso.co.jp>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-09-04 11:49:16 +01:00
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
Wolfram Sang 3cc2d009bc drivers/i2c/busses: don't check resource with devm_ioremap_resource
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-12 20:39:06 +02:00
Thierry Reding 84dbf809fb i2c: Convert to devm_ioremap_resource()
Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

devm_ioremap_resource() provides its own error messages so all explicit
error messages can be removed from the failure code paths.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-24 13:33:23 -08:00
Bill Pemberton 0b255e927d i2c: remove __dev* attributes from subsystem
CONFIG_HOTPLUG is going away as an option.  As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-12-22 20:13:45 +01:00
Wolfram Sang 45fd5e4ad2 i2c: rcar: fix section mismatch
Give the driver struct a name according to the 'standard' to fix:

WARNING: vmlinux.o(.data+0x11798): Section mismatch in reference from the variable rcar_i2c_drv to the function .devinit.text:rcar_i2c_probe()
...
WARNING: vmlinux.o(.data+0x1179c): Section mismatch in reference from the variable rcar_i2c_drv to the function .devexit.text:rcar_i2c_remove()

Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
2012-11-13 11:24:15 +01:00
Kuninori Morimoto b53f4baf8b i2c: rcar: used devm_request_and_ioremap() instead of devm_ioremap()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-13 09:27:28 +01:00
Kuninori Morimoto 6ccbe60713 i2c: add Renesas R-Car I2C driver
R-Car I2C is similar with SH7760 I2C.
But the SH7760 I2C driver had many workaround operations, since H/W had bugs.
Thus, it was pointless to keep compatible between SH7760 and R-Car I2C drivers.
This patch creates new Renesas R-Car I2C driver.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-10-08 12:46:25 +02:00