Commit Graph

55 Commits

Author SHA1 Message Date
Ludovic Desroches a9bed6b10b i2c: at91: manage unexpected RXRDY flag when starting a transfer
In some cases, we could start a new i2c transfer with the RXRDY flag
set. It is not a clean state and it leads to print annoying error
messages even if there no real issue. The cause is only having garbage
data in the Receive Holding Register because of a weird behavior of the
RXRDY flag.

Reported-by: Peter Rosin <peda@lysator.liu.se>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Tested-by: Peter Rosin <peda@lysator.liu.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 93563a6a71 ("i2c: at91: fix a race condition when using the DMA controller")
Cc: stable@vger.kernel.org #4.1
2015-10-26 15:44:59 +01:00
Cyrille Pitchen 6f6ddbb09d i2c: at91: fix write transfers by clearing pending interrupt first
In some cases a NACK interrupt may be pending in the Status Register (SR)
as a result of a previous transfer. However at91_do_twi_transfer() did not
read the SR to clear pending interruptions before starting a new transfer.
Hence a NACK interrupt rose as soon as it was enabled again at the I2C
controller level, resulting in a wrong sequence of operations and strange
patterns of behaviour on the I2C bus, such as a clock stretch followed by
a restart of the transfer.

This first issue occurred with both DMA and PIO write transfers.

Also when a NACK error was detected during a PIO write transfer, the
interrupt handler used to wrongly start a new transfer by writing into the
Transmit Holding Register (THR). Then the I2C slave was likely to reply
with a second NACK.

This second issue is fixed in atmel_twi_interrupt() by handling the TXRDY
status bit only if both the TXCOMP and NACK status bits are cleared.

Tested with a at24 eeprom on sama5d36ek board running a linux-4.1-at91
kernel image. Adapted to linux-next.

Reported-by: Peter Rosin <peda@lysator.liu.se>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Tested-by: Peter Rosin <peda@lysator.liu.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 93563a6a71 ("i2c: at91: fix a race condition when using the DMA controller")
Cc: stable@vger.kernel.org #4.1
2015-10-22 15:14:41 +02:00
Cyrille Pitchen f30dc5208c i2c: at91: fix code checker warnings
buf_len is a size_t, so unsigned, but was tested with '<= 0'.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-11 22:12:53 +09:00
Cyrille Pitchen 5e3cfc6c4e i2c: at91: add support to FIFOs
When FIFOs are available and enabled, the driver now configures the Atmel
eXtended DMA Controller to perform word accesses instead of byte accesses
when possible.
The actual access width depends on the size of the buffer to transmit.

To enable FIFO support the "atmel,fifo-size" property must be set properly
in the I2C controller node of the device tree.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-10 21:55:36 +09:00
Cyrille Pitchen 6ce461ea50 i2c: at91: print hardware version
The probe() function now prints the hardware version of the I2C
controller.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
[wsa: s/version/hw version/] for clarity]
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-10 21:54:53 +09:00
Cyrille Pitchen 0ef6f3213d i2c: at91: add support for new alternative command mode
The alternative command mode was introduced to simplify the transmission
of STOP conditions and to solve timing and latency issues around them.

This mode relies on a new register, the Alternative Command Register,
which must be set at the same time as the Master Mode Register. This new
register was designed to allow simple setup of basic combined transactions
built from up to two unitary transactions.

Indeed, the ACR is split into two areas, which describe one unitary
transaction each. Each area is filled with Data Length 8bit counter, a
Direction and a PEC Request bit. The PEC bit is only used in SMBus mode
and is not supported by this driver yet. Also when using alternative
command mode, the MREAD bit from the Master Mode Register is ignored.
Instead the Direction bits from ACR are used to setup the direction, read
or write, of each unitary transaction. Finally the 8bit counters must
filled with the data length of their respective transaction. Then if only
one transaction is to be used, the data length of the second one must be
set to zero. At the moment, this driver uses only the first transaction.

In addition to MMR and ACR, the Control Register also need to be written
to enable the alternative command mode. That's the purpose of its ACMEN
bit, which stands for Alternative Command Mode Enable.

Note that the alternative command mode is compatible with the use of the
Internal Address Register. So combined transactions for eeprom read are
actually implemented with the Internal Address Register. This register is
written with up to 3 bytes, which are the internal address sent to the
slave through the first write transaction. Then the first area of the ACR
describe the write transaction to follow, which carries the data to be
read from the eeprom. The second area of the ACR is not used so its Data
Length 8bit counter is cleared.

For each byte sent or received by the device, the Data Length 8bit counter
is decremented. When it reaches 0, a STOP condition is automatically sent.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-10 21:52:42 +09:00
Cyrille Pitchen e84cf8f03f i2c: at91: use BIT() macro to define register bits
This patch just fixes typo before applying later patches which will use
register bits with index above 16.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-10 21:52:12 +09:00
Cyrille Pitchen 93563a6a71 i2c: at91: fix a race condition when using the DMA controller
For TX transactions, the TXCOMP bit in the Status Register is cleared
when the first data is written into the Transmit Holding Register.

In the lines from at91_do_twi_transfer():
at91_twi_write_data_dma(dev);
at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP);

the TXCOMP interrupt may be enabled before the DMA controller has
actually started to write into the THR. In such a case, the TXCOMP bit
is still set into the Status Register so the interrupt is triggered
immediately. The driver understands that a transaction completion has
occurred but this transaction hasn't started yet. Hence the TXCOMP
interrupt is no longer enabled by at91_do_twi_transfer() but instead
by at91_twi_write_data_dma_callback().

Also, the TXCOMP bit in the Status Register in not a clear on read flag
but a snapshot of the transmission state at the time the Status
Register is read.
When a NACK error is dectected by the I2C controller, the TXCOMP, NACK
and TXRDY bits are set together to 1 in the SR. If enabled, the TXCOMP
interrupt is triggered at the same time. Also setting the TXRDY to 1
triggers the DMA controller to write the next data into the THR. Such
a write resets the TXCOMP bit to 0 in the SR. So depending on when the
interrupt handler reads the SR, it may fail to detect the NACK error
if it relies on the TXCOMP bit. The NACK bit and its interrupt should
be used instead.

For RX transactions, the TXCOMP bit in the Status Register is cleared
when the START bit is set into the Control Register. However to unify
the management of the TXCOMP bit when the DMA controller is used, the
TXCOMP interrupt is now enabled by the DMA callbacks for both TX and
RX transfers.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Cc: stable@vger.kernel.org #3.10 and later
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-06-10 21:51:49 +09:00
Nicholas Mc Guire 1c42aca54f i2c: at91: fixup return type of wait_for_completion_timeout
Return type of wait_for_completion_timeout is unsigned long not int. This
patch adds a timeout variable of appropriate type and fixes up the assignment.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-15 10:54:08 +01:00
Wolfram Sang a7405844da i2c: at91: make use of the new infrastructure for quirks
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-By: Ludovic Desroches <ludovic.desroches@atmel.com>
2015-03-13 15:10:52 +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
Ludovic Desroches 727f9c2dad i2c: at91: enable probe deferring on dma channel request
If dma controller is not probed, defer i2c probe.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:29 +01:00
Arnd Bergmann dc6df6e90d i2c: at91: remove legacy DMA support
Since at91sam9g45 is now DT-only, all DMA capable users of this driver
are using the DT case, and the legacy support can be removed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-21 19:02:01 +01:00
Wenyou Yang 62d10c402f i2c: at91: adopt pinctrl support
Amend the at91 i2c pin controller to set the state of the pins to:
- "default" on resume.
- "sleep" on suspend().

This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 16:50:24 +01:00
Wenyou Yang 36765293cd i2c: at91: add support for system PM
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-10 09:35:00 +01:00
Wenyou Yang d64a818859 i2c: at91: add support for runtime PM
Drivers should put the device into low power states proactively whenever the
device is not in use. Thus implement support for runtime PM and use the
autosuspend feature to make sure that we can still perform well in case we see
lots of i2c traffic within short period of time.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-10 09:34:59 +01:00
Wolfram Sang 11cfbfb098 i2c: at91: don't account as iowait
iowait is for blkio [1]. I2C shouldn't use it.

[1] https://lkml.org/lkml/2014/11/3/317

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@kernel.org
2014-11-07 18:56:31 +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
Marek Roszko 75b81f339c i2c: at91: add bound checking on SMBus block length bytes
The driver was not bound checking the received length byte to ensure it was within the
the buffer size that is allocated for SMBus blocks. This resulted in buffer overflows
whenever an invalid length byte was received.
It also failed to ensure the length byte was not zero. If it received zero, it would end up
in an infinite loop as the at91_twi_read_next_byte function returned immediately without
allowing RHR to be read to clear the RXRDY interrupt.

Tested agaisnt a SMBus compliant battery.

Signed-off-by: Marek Roszko <mark.roszko@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-09-02 14:29:33 +02:00
Simon Lindgren 6721f28a26 i2c: at91: Fix a race condition during signal handling in at91_do_twi_xfer.
There is a race condition in at91_do_twi_xfer when signals arrive.
If a signal is recieved while waiting for a transfer to complete
wait_for_completion_interruptible_timeout() will return -ERESTARTSYS.
This is not handled correctly resulting in interrupts still being
enabled and a transfer being in flight when we return.

Symptoms include a range of oopses and bus lockups. Oopses can happen
when the transfer completes because the interrupt handler will corrupt
the stack. If a new transfer is started before the interrupt fires
the controller will start a new transfer in the middle of the old one,
resulting in confused slaves and a locked bus.

To avoid this, use wait_for_completion_io_timeout instead so that we
don't have to deal with gracefully shutting down the transfer and
disabling the interrupts.

Signed-off-by: Simon Lindgren <simon@aqwary.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-09-02 14:29:20 +02:00
Wolfram Sang 28772ac871 drivers/i2c/busses: use correct type for dma_map/unmap
dma_{un}map_* uses 'enum dma_data_direction' not 'enum dma_transfer_direction'.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@kernel.org
2014-08-01 19:43:51 +02:00
Wolfram Sang b850579afe i2c: i2c-at91: 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 22:59:56 +02:00
Marek Roszko 75b6c4b68f i2c: at91: Add device tree property to set clock-frequency
This adds the ability to set "clock-frequency" in the device tree for the at91
i2cbus following the naming of other i2c bus implementations. If the property
is not set,the clock frequency will default to the previously used define
of 100KHz.

Signed-off-by: Marek Roszko <mark.roszko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-12 08:26:04 +01:00
Wolfram Sang 4880eef1ab i2c: i2c-at91: 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: Ludovic Desroches <ludovic.desroches@atmel.com>
2014-03-05 17:16:51 +01:00
jean-jacques hiblot d9a3afc2cf i2c: at91: add a new compatibility string for the at91sam9261
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-16 11:14:27 +01:00
Wolfram Sang 16735d022f tree-wide: use reinit_completion instead of INIT_COMPLETION
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 09:32:21 +09:00
Wolfram Sang 687b81d083 i2c: move OF helpers into the core
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:20 +02:00
Ludovic Desroches d877a721e2 i2c: at91: convert to dma_request_slave_channel_compat()
Use generic DMA DT helper. Platforms booting with or without DT populated are
both supported.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-16 11:10:14 +02:00
Lars-Peter Clausen bf51a8c5e0 i2c: Ignore return value of i2c_del_adapter()
i2c_del_adapter() always returns 0. So all checks testing whether it will be
non zero will always evaluate to false and the conditional code is dead code.
This patch updates all callers of i2c_del_mux_adapter() to ignore the return
value and assume that it will always succeed (which it will). In a subsequent
patch the return type of i2c_del_adapter() will be made void.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02 07:06:03 +02:00
Sachin Kamat 600abeadf3 i2c: at91: Use of_match_ptr() macro
This eliminates having an #ifdef returning NULL for the case
when OF is disabled.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-29 12:41:43 +01:00
Linus Torvalds 52caa59ed3 Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Highlights:

   - new drivers for Intel ismt & Broadcom bcm2835
   - a number of drivers got support for more variants and mostly got
     cleaned up on the way (sis630, i801, at91, tegra, designware)
   - i2c got rid of all *_set_drvdata(..., NULL) on remove/probe failure
   - removed the i2c_smbus_process_call from the core since there are no
     users
   - mxs can now switch between PIO and DMA depending on the message
     size and the bus speed can now be arbitrary

  In addition, there is the usual bunch of fixes, cleanups, devm_*
  conversions, etc"

Fixed conflict (and buggy devm_* conversion) in i2c-s3c2410.c

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (39 commits)
  i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
  i2c: pxa: remove incorrect __exit annotations
  i2c: ocores: Fix pointer to integer cast warning
  i2c: tegra: remove warning dump if timeout happen in transfer
  i2c: fix i2c-ismt.c printk format warning
  i2c: i801: Add Device IDs for Intel Wellsburg PCH
  i2c: add bcm2835 driver
  i2c: ismt: Add Seth and Myself as maintainers
  i2c: sis630: checkpatch cleanup
  i2c: sis630: display unsigned hex
  i2c: sis630: use hex to constants for SMBus commands
  i2c: sis630: fix behavior after collision
  i2c: sis630: clear sticky bits
  i2c: sis630: Add SIS964 support
  i2c: isch: Add module parameter for backbone clock rate if divider is unset
  i2c: at91: fix unsed variable warning when building with !CONFIG_OF
  i2c: Adding support for Intel iSMT SMBus 2.0 host controller
  i2c: sh_mobile: don't send a stop condition by default inside transfers
  i2c: sh_mobile: eliminate an open-coded "goto" loop
  i2c: sh_mobile: fix timeout error handling
  ...
2013-02-26 09:41:53 -08:00
Joachim Eastwood 4182b434bf i2c: at91: fix unsed variable warning when building with !CONFIG_OF
Commit 70d46a2 "i2c: at91: add dt support to i2c-at91"
added DT only support for at91sam9x5. Building i2c-at91
without CONFIG_OF now warns about at91sam9x5_config as
being unused.

  drivers/i2c/busses/i2c-at91.c:556:30: warning: 'at91sam9x5_config' defined but not used [-Wunused-variable]

Move at91sam9x5_config under the defined(CONFIG_OF)
guard as new AT91 SoCs will be DT only.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2013-02-10 19:55:26 +01:00
Joachim Eastwood 631056c399 i2c: at91: add of_device_id entry for at91rm9200
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Acked-by: Ludovic Ddesroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-01-28 05:26:43 +01:00
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
Ludovic Desroches 60937b2cdb i2c: at91: add dma support
Add dma support for Atmel TWI which is available on sam9x5 and later.

When using dma for reception, you have to read only n-2 bytes. The last
two bytes are read manually. Don't doing this should cause to send the
STOP command too late and then to get extra data in the receive
register.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-24 20:27:30 +01:00
Ludovic Desroches 5f433819b3 i2c: at91: change struct members indentation
Replace tabs for struct members indentation by space to minimise line changes
when adding new members which would require extra tabs to keep alignment.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-24 20:27:24 +01:00
Ludovic Desroches cd32e6ccdd i2c: at91: fix compilation warning
This patch fixes the following warning:
drivers/i2c/busses/i2c-at91.c: In function ‘at91_twi_get_driver_data’:
drivers/i2c/busses/i2c-at91.c:411:3: warning: return discards ‘const’ qualifier from pointer target type [enabled by default]

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-24 20:27:18 +01:00
Ludovic Desroches 7c3fe64d13 i2c: at91: fix SMBus quick command
The driver claims to support SMBus quick command but it was not the
case. This patch fixes this issue. Without it, i2cdetect finds imaginary
devices. And with some IP versions, trying to send 0 byte can cause
issue when writing data to an EEPROM.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

[wsa: improved the commit message]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 10:28:28 +01:00
Ludovic Desroches 70d46a241e i2c: at91: add dt support to i2c-at91
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nikolaus Voss <n.voss@weinmann.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 14:49:15 +02:00
Nikolaus Voss fac368a040 i2c: at91: add new driver
This driver has the following properties compared to the old driver:
1. Support for multiple interfaces.
2. Interrupt driven I/O as opposed to polling/busy waiting.
3. Support for _one_ repeated start (Sr) condition, which is enough
   for most real-world applications including all SMBus transfer types.
   (The hardware does not support issuing arbitrary Sr conditions on the
    bus.)

testing: SoC: at91sam9g45
	 - BQ20Z80 battery SMBus client.
	 - on a 2.6.38 kernel with several i2c clients (temp-sensor,
	   audio-codec, touchscreen-controller, w1-bridge, io-expanders)

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Tested-by: Hubert Feurstein <h.feurstein@gmail.com>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>

[wsa: squashed with the following patches from Ludovic to have some flaws
fixed:
        i2c: at91: use managed resources
        i2c: at91: add warning about transmission issues for some devices
        i2c: at91: use an id table for SoC dependent parameters
]

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 14:49:13 +02:00
Nikolaus Voss a879e9c34b i2c: at91: remove old polling driver
It will get replaced by a superior one. Safe to remove since this one
depends on BROKEN anyhow.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>

[wsa: added commit message]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 14:49:12 +02:00
Rafael J. Wysocki f277d27cc4 i2c-at91: Use struct dev_pm_ops for power management
Make the AT91 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>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-12 12:04:32 +02:00
Axel Lin a3664b51c7 i2c/busses: Use module_platform_driver()
Convert the drivers in drivers/i2c/busses/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Yong Zhang <yong.zhang0@gmail.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-01-12 20:32:04 +01:00
H Hartley Sweeten 2178218027 i2c: Use <linux/io.h> instead of <asm/io.h>
As warned by checkpatch.pl, <linux/io.h> should be used instead of
<asm/io.h>.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:41:01 +02:00
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
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
Adrian Bunk 7a8fc9b248 removed unused #include <linux/version.h>'s
This patch lets the files using linux/version.h match the files that
#include it.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-23 12:14:12 -07:00
Russell King a09e64fbc0 [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach
This just leaves include/asm-arm/plat-* to deal with.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:55:48 +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