Commit Graph

159 Commits

Author SHA1 Message Date
Nishanth Menon ff370257ed i2c: omap: fix usage of IS_ERR_VALUE with pm_runtime_get_sync
we use IS_ERR_VALUE to check for error values of pm_runtime_get_sync,
when the value can only be < 0 in the case of err. Replace the
check with a simpler < 0 check.

This fixes the coccicheck warnings:
linux-2.6/drivers/i2c/busses/i2c-omap.c:1157:5-24:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 1158
linux-2.6/drivers/i2c/busses/i2c-omap.c:1278:7-26:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 1279
drivers/i2c/busses/i2c-omap.c:638:5-24:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 639

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-27 18:53:26 +01:00
Wolfram Sang 04eceb00e5 i2c: i2c-omap: 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 17:16:48 +01:00
Linus Torvalds dc418f6e6a Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
 "Some easy but needed fixes for i2c drivers since rc1"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: bcm2835: Linking platform nodes to adapter nodes
  i2c: omap: raw read and write endian fix
  i2c: i2c-bcm-kona: Fix module build
  i2c: i2c-diolan-u2c: different usb endpoints for DLN-2-U2C
  i2c: bcm-kona: remove duplicated include
  i2c: davinci: raw read and write endian fix
2013-11-29 09:55:13 -08:00
Victor Kamensky 40b13ca8dc i2c: omap: raw read and write endian fix
All OMAP IP blocks expect LE data, but CPU may operate in BE mode.
Need to use endian neutral functions to read/write h/w registers.
I.e instead of __raw_read[lw] and __raw_write[lw] functions code
need to use read[lw]_relaxed and write[lw]_relaxed functions.
If the first simply reads/writes register, the second will byteswap
it if host operates in BE mode.

Changes are trivial sed like replacement of __raw_xxx functions
with xxx_relaxed variant.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-11-27 19:26:05 +01:00
Olof Johansson 5c1f34c42d Merge tag 'omap-for-v3.13/more-fixes-for-merge-window-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
From Tony Lindgren:
Few more fixes for issues found booting older omaps using device tree.
Also few randconfig build fixes and removal of some dead code for omap4
as it no longer has legacy platform data based booting support.

* tag 'omap-for-v3.13/more-fixes-for-merge-window-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: Remove legacy omap4_twl6030_hsmmc_init
  ARM: OMAP2+: Remove legacy mux code for display.c
  ARM: OMAP2+: Fix undefined reference to set_cntfreq
  gpio: twl4030: Fix passing of pdata in the device tree case
  gpio: twl4030: Fix regression for twl gpio output
  ARM: OMAP2+: More randconfig fixes for reconfigure_io_chain
  ARM: dts: Fix omap2 specific dtsi files by adding the missing entries
  ARM: OMAP2+: Fix GPMC and simplify bootloader timings for 8250 and smc91x
  i2c: omap: Fix missing device tree flags for omap2
2013-11-25 13:34:49 -08:00
Tony Lindgren 4c624840eb i2c: omap: Fix missing device tree flags for omap2
As we claim to support device tree for mach-omap2, we
should have the necessary flags in the driver to make it
usable.

Cc: linux-i2c@vger.kernel.org
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2013-11-15 14:32:34 -08:00
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
Taras Kondratiuk 4cdbf7d346 i2c: omap: Clear ARDY bit twice
Initially commit cb527ede1b
"i2c-omap: Double clear of ARDY status in IRQ handler"
added a workaround for undocumented errata ProDB0017052.
But then commit 1d7afc9594
"i2c: omap: ack IRQ in parts" refactored code and missed
one of ARDY clearings. So current code violates errata.
It causes often i2c bus timeouts on my Pandaboard.

This patch adds a second clearing in place.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2013-10-10 10:22:32 +02:00
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
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
Grygorii Strashko cda2109a26 i2c: omap: query STP always when NACK is received
According to I2C specification the NACK should be handled as folowing:
"When SDA remains HIGH during this ninth clock pulse, this is defined as the Not
Acknowledge signal. The master can then gene rate either a STOP condition to
abort the transfer, or a repeated START condition to start a new transfer."
[http://www.nxp.com/documents/user_manual/UM10204.pdf]

The same is recomened by TI I2C wiki:
 http://processors.wiki.ti.com/index.php/I2C_Tips

Currently, the OMAP I2C driver interrupts I2C trunsfer in case of NACK, but
It queries Stop condition OMAP_I2C_CON_REG.STP=1 only if NACK has been received
during the last message transmitting/recieving.
This may lead to stuck Bus in "Bus Busy" until I2C IP reset (idle/enable).

Hence, fix it by querying Stop condition (STP) always when NACK is received.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Hein Tibosch <hein_tibosch@yahoo.es>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-19 14:08:19 +02:00
Wolfram Sang 3f97b62fab drivers/i2c/busses: don't use devm_pinctrl_get_select_default() in probe
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for setting the default pins. Compile tested only.

Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-07 17:36:30 +02:00
Oleksandr Dmytryshyn 4368de19ed i2c: omap: correct usage of the interrupt enable register
We've been lucky not to have any interrupts fire during the suspend
path, otherwise we would have unpredictable behaviour in the kernel.

Based on the logic of the kernel code interrupts from i2c should be
prohibited during suspend. Kernel writes 0 to the I2C_IE register in
the omap_i2c_runtime_suspend() function. In the other side kernel
writes saved interrupt flags to the I2C_IE register in
omap_i2c_runtime_resume() function. I.e. interrupts should be disabled
during suspend.

This works for chips with version1 registers scheme. Interrupts are
disabled during suspend. For chips with version2 scheme registers
writting 0 to the I2C_IE register does nothing (because now the
I2C_IRQENABLE_SET register is located at this address). This register
is used to enable interrupts. For disabling interrupts
I2C_IRQENABLE_CLR register should be used.

Because the registers I2C_IRQENABLE_SET and I2C_IE have the same
addresses, the interrupt enabling procedure is unchanged.

I've checked that interrupts in the i2c controller are still enabled
after writting 0 to the I2C_IRQENABLE_SET register. With this patch
interrupts are disabled in the omap_i2c_runtime_suspend() function.

Patch is based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tag: v3.10-rc2

Verified on OMAP4430.

Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-19 12:04:26 +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
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
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
Greg Kroah-Hartman 422d26b6ec Merge 3.8-rc5 into driver-core-next
This resolves a gpio driver merge issue pointed out in linux-next.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-25 21:06:30 -08:00
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
Aaro Koskinen 9eb13cf3ec i2c: omap: fix draining irq handling
Commit 0bdfe0cb80 (i2c: omap: sanitize
exit path) changed the interrupt handler to exit early and complete
the transfer after the draining IRQ is handled. As a result, the ARDY
may not be cleared properly, and it may cause all future I2C transfers
to timeout with "timeout waiting for bus ready". This is reproducible
at least with N900 when twl4030_gpio makes a long write (> FIFO size)
during the probe (http://marc.info/?l=linux-omap&m=135818882610432&w=2).

The fix is to continue until we get ARDY interrupt that completes the
transfer. Tested with 3.8-rc4 + N900: 20 boots in a row without errors;
without the patch the problem triggers after few reboots.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-01-22 16:17:05 +01:00
Aaro Koskinen 2c5de558cd i2c: omap: errata i462: fix incorrect ack for arbitration lost interrupt
The errata handling function acks wrong interrupt in case of "Arbitration
lost". Fix it.

Discovered during code review, the real impact of the bug is unknown.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-01-22 16:17:04 +01:00
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
Shubhrajyoti D 972deb4f49 i2c: omap: Remove the OMAP_I2C_FLAG_RESET_REGS_POSTIDLE flag
The OMAP_I2C_FLAG_RESET_REGS_POSTIDLE is not used anymore
in the i2c driver. Remove the flag.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-28 11:36:32 +01:00
Shubhrajyoti D 1ab3604595 i2c: omap: Move the remove constraint
Currently we just queue the transfer and release the
qos constraints, however we do not wait for the transfer
to complete to release the constraint. Move the remove
constraint after the bus busy as we are sure that the
transfers are completed by then.

Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-16 15:18:52 +01:00
Wolfram Sang 27e0fbefa5 i2c: omap: don't save a value only needed for read-clearing
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2012-11-14 19:52:12 +01:00
Shubhrajyoti D ca85e248b6 i2c: omap: cleanup the sysc write
Currently after the reset the sysc is written with hardcoded values.
The patch reads the sysc register and writes back the same value
after reset.

- Some unnecessary rev checks can be optimised.
- Also due to whatever reason the hwmod flags are changed
we will not reset the values.
- In some of the cases the minor values of the 2430 register
is different(0x37) in that case the autoidle setting may be missed.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:43 +01:00
Shubhrajyoti D 554c96744a i2c: omap: Restore i2c context always
Currently the restore is done based on the flag
OMAP_I2C_FLAG_RESET_REGS_POSTIDLE.

This helps the following
- The driver is always capable of restoring regardless
of the off mode support being there or not.

- While testing omap2430 it is found that in case of certain
error paths (timeout) a reset is done. However the restore
never happens as it is dependent on the POSTIDLE flag.
The other option would be to call a restore in the reset
case. As there are only a few registers to be restored
the penalty in the idle case should not be much.

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:42 +01:00
Shubhrajyoti D d6c842ad56 i2c: omap: make reset a seperate function
Implement reset as a separate function.
This will enable us to make sure that we don't do the
calculation again on every transfer.
Also at probe the reset is not added as the hwmod is doing that
for us.

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:42 +01:00
Shubhrajyoti D 95dd303266 i2c: omap: re-factor omap_i2c_init function
re-factor omap_i2c_init() so that we can re-use it for resume.
While at it also remove the bufstate variable as we write it
in omap_i2c_resize_fifo for every transfer.

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:41 +01:00
Shubhrajyoti D 2c88ab8c5a ARM: i2c: omap: Remove the i207 errata flag
The commit [i2c: omap: use revision check for OMAP_I2C_FLAG_APPLY_ERRATA_I207]
uses the revision id instead of the flag. So the flag can be safely removed.

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:40 +01:00
Shubhrajyoti D cd10c74aee i2c: omap: remove the dtrev
The dtrev is used only for the comments. Remove the same and use
the scheme instead to know if it is version2.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:39 +01:00
Shubhrajyoti D a748021ccb i2c: omap: use revision check for OMAP_I2C_FLAG_APPLY_ERRATA_I207
The errata i207 is enabled for 2430 and 3xxx. Use the revision check
to enable the erratum instead.

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:39 +01:00
Shubhrajyoti D 47dcd0161a i2c: omap: Fix the revision register read
The revision register on OMAP4 is a 16-bit lo and a 16-bit
hi. Currently the driver reads only the lower 8-bits.
Fix the same by preventing the truncating of the rev register
for OMAP4.

Also use the scheme bit ie bit-14 of the hi register to know if it
is OMAP_I2C_IP_VERSION_2.

On platforms previous to OMAP4 the offset 0x04 is IE register whose
bit-14 reset value is 0, the code uses the same to its advantage.

Also since the omap_i2c_read_reg uses reg_map_ip_* a raw_readw is done
to fetch the revision register.

The dev->regs is populated after reading the rev_hi. A NULL check
has been added in the resume handler to prevent the access before
the setting of the regs.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:38 +01:00
Sebastien Guiriec 2d4b4520a5 i2c: omap: adopt pinctrl support
Some GPIO expanders need some early pin control muxing. Due to
legacy boards sometimes the driver uses subsys_initcall instead of
module_init. This patch takes advantage of defer probe feature
and pin control in order to wait until pin control probing before
GPIO driver probing. It has been tested on OMAP5 board with TCA6424
driver.

Signed-off-by: Sebastien Guiriec <s-guiriec@ti.com>
Acked-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:37 +01:00
Felipe Balbi d60ece5f01 i2c: omap: ensure writes to dev->buf_len are ordered
if we allow compiler reorder our writes, we could
fall into a situation where dev->buf_len is reset
for no apparent reason.

This bug was found with a simple script which would
transfer data to an i2c client from 1 to 1024 bytes
(a simple for loop), when we got to transfer sizes
bigger than the fifo size, dev->buf_len was reset
to zero before we had an oportunity to handle XDR
Interrupt. Because dev->buf_len was zero, we entered
omap_i2c_transmit_data() to transfer zero bytes,
which would mean we would just silently exit
omap_i2c_transmit_data() without actually writing
anything to DATA register. That would cause XDR
IRQ to trigger forever and we would never transfer
the remaining bytes.

After adding the memory barrier, we also drop resetting
dev->buf_len to zero in omap_i2c_xfer_msg() because
both omap_i2c_transmit_data() and omap_i2c_receive_data()
will act until dev->buf_len reaches zero, rendering the
other write in omap_i2c_xfer_msg() redundant.

This patch has been tested with pandaboard for a few
iterations of the script mentioned above.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 17:44:37 +01:00
Paul Walmsley 49839dc939 Revert "ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints"
This reverts commit 3db11feffc
(ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints).
This commit causes I2C timeouts to appear on several OMAP3430/3530-based
boards:

  http://marc.info/?l=linux-arm-kernel&m=135071372426971&w=2
  http://marc.info/?l=linux-arm-kernel&m=135067558415214&w=2
  http://marc.info/?l=linux-arm-kernel&m=135216013608196&w=2

and appears to have been sent for merging before one of its prerequisites
was merged:

  http://marc.info/?l=linux-arm-kernel&m=135219411617621&w=2

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14 11:51:15 +01:00
Linus Torvalds 12250d843e Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull i2c-embedded changes from Wolfram Sang:
 "The changes for i2c-embedded include:

   - massive rework of the omap driver
   - massive rework of the at91 driver.  In fact, the old driver gets
     removed; I am okay with this approach since the old driver was
     depending on BROKEN and its limitations made it practically
     unusable, so people used bitbanging instead.  But even if there are
     users, there is no platform_data or module parameter which would
     need to be converted.  It is just another driver doing I2C
     transfers, just way better.  Modifications of arch/arm/at91 related
     files have proper acks from the maintainer.
   - new driver for R-Car I2C
   - devicetree and generic_clock conversions and fixes
   - usual driver fixes and changes.

  The rework patches have come a long way and lots of people have been
  involved in creating/testing them.  Most patches have been in
  linux-next at least since 3.6-rc5.  A few have been added in the last
  week, I have to admit.

  An unexpected (but welcome :)) peak in private life is the cause for
  that.  The "late" patches shouldn't cause any merge conflicts and I
  will have a special eye on them during the stabilization phase.  This
  is an exception and I want to have the patches in place properly in
  time again for the next kernels."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (44 commits)
  MXS: Implement DMA support into mxs-i2c
  i2c: add Renesas R-Car I2C driver
  i2c: s3c2410: use clk_prepare_enable and clk_disable_unprepare
  ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints
  i2c: nomadik: Add Device Tree support to the Nomadik I2C driver
  i2c: algo: pca: Fix chip reset function for PCA9665
  i2c: mpc: Wait for STOP to hit the bus
  i2c: davinci: preparation for switch to common clock framework
  omap-i2c: fix incorrect log message when using a device tree
  i2c: omap: sanitize exit path
  i2c: omap: switch over to autosuspend API
  i2c: omap: remove unnecessary pm_runtime_suspended check
  i2c: omap: switch to threaded IRQ support
  i2c: omap: remove redundant status read
  i2c: omap: get rid of the "complete" label
  i2c: omap: resize fifos before each message
  i2c: omap: simplify IRQ exit path
  i2c: omap: always return IRQ_HANDLED
  i2c: omap: simplify errata check
  i2c: omap: bus: add a receiver flag
  ...
2012-10-11 10:27:51 +09:00
Jean Pihet 3db11feffc ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints
Convert the driver from the outdated omap_pm_set_max_mpu_wakeup_lat
API to the new PM QoS API.
Since the constraint is on the MPU subsystem, use the PM_QOS_CPU_DMA_LATENCY
class of PM QoS. The resulting MPU constraints are used by cpuidle to
decide the next power state of the MPU subsystem.

The I2C device latency timing is derived from the FIFO size and the
clock speed and so is applicable to all OMAP SoCs.

Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-10-06 13:43:38 +02:00
Olof Johansson 1a87676206 Merge branch 'ofdeviceiddata' of git://git.pengutronix.de/git/ukl/linux into next/fixes-non-critical
From  "Uwe Kleine-Knig" <u.kleine-koenig@pengutronix.de>:

this is the 2nd version of this series whose goal is to make struct
of_device_id.data const. Conceptually a driver must not modify the data
contained there so making it const is the right thing.

v1 of this series was sent with Message-id:
1342182734-321-1-git-send-email-y. Changes since then are:
 - powerpc fixes
 - several new consts that were found by Arnd that are possible after
   patch 19.

Arnd suggested to take this series via arm-soc late for 3.6 in one go
because patch 19 depends on the former patches but is a precondition to
the latter and it fixes a few warnings. So getting it in via the
respective maintainer trees would need a much bigger coordination
effort. That means I prefer getting Acks over you taking the patch.

Vinod Koul already took
        dmaengine: at_hdmac: add a few const qualifiers
that is in next-20120723 as 7fd63ccdad now. Vinod, I don't follow your
pull requests, but assuming you didn't let it already pull for 3.6 I
suggest you drop it from your queue and I just take your Ack.

This series was build tested for arm (all defconfigs) and powerpc (all
defconfigs and an allyesconfig) and grep didn't find more issues. As
before it introduces a warning in drivers/regulator/twl-regulator.c.
This driver does modify its .of_match_table when a device is bound which
doesn't fits the concept of independant devices. Arnd noticed another
new warning in drivers/scsi/qlogicpti.c that isn't that easy to resolve,
because the pointer to (now) const data is passed as first argument to
scsi_host_alloc. To fix that properly struct Scsi_Host.hostt needs to
get a const, too. Alternatively I could introduce a cast removing the
const, but I don't like that.

* 'ofdeviceiddata' of git://git.pengutronix.de/git/ukl/linux: (25 commits)
  dma: tegra: make data used as *of_device_id.data const
  can: mpc5xxx_can: make data used as *of_device_id.data const
  macintosh/mediabay: make data used as *of_device_id.data const
  i2c/mpc: make data used as *of_device_id.data const
  mfd/da9052: make i2c_device_id array const
  powerpc/fsl_msi: drop unneeded cast to non-const pointer
  gpio/gpio-omap: make platformdata used as *of_device_id.data const
  of: add const to struct *of_device_id.data
  dma: tegra: make tegra_dma.chip_data a pointer to const data
  watchdog/mpc8xxx: add a const qualifier
  powerpc/celleb_pci: add a const qualifier
  powerpc/fsl_msi: add a const qualifier
  powerpc/83xx: add a const qualifier
  macintosh/mediabay: add a const qualifier
  mmc/omap_hsmmc: add a const qualifier
  i2c/mpc: add a const qualifier
  i2c/i2c-omap: add a const qualifier
  gpio/mpc8xxx: add a const qualifier
  gpio/gpio-omap.c: add a const qualifier
  misc/atmel_tc: make atmel_tc.tcb_config member point to const data

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[olof: repulled a v3 version of the branch that rebased to add some more
acked-bys and added one more patch on top for tegra]
Signed-off-by: Olof Johansson <olof@lixom.net>
2012-09-13 00:15:00 -07:00
Florian Vaussard c5d3cd6dc2 omap-i2c: fix incorrect log message when using a device tree
When booting using a device tree, the adapter number is dynamically
assigned after the log message is sent.
This patch modifies the log message to get a correct adapter id.

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Tested-by: Benoit Cousson <b-cousson@ti.com>
Acked-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:54:14 +02:00
Felipe Balbi 0bdfe0cb80 i2c: omap: sanitize exit path
move the goto out label one line down, so that
it can be used when stat is read as zero. All
other exits, can be done with a break statement.

While at that, also break out as soon as we
complete draining IRQ, since at that time
we know we transferred everything there was
to be transferred.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:04:18 +02:00
Felipe Balbi 6d8451d55a i2c: omap: switch over to autosuspend API
this helps us reduce unnecessary pm transitions
in case we have another i2c message starting soon.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:04:10 +02:00
Felipe Balbi e3a36b207f i2c: omap: remove unnecessary pm_runtime_suspended check
before starting any messages we call pm_runtime_get_sync()
which will make sure that by the time we program a transfer
and our IRQ handler gets called, we're not suspended
anymore.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:04:03 +02:00
Felipe Balbi 3b2f8f82da i2c: omap: switch to threaded IRQ support
for OMAP2, we can easily switch over to threaded
IRQs on the I2C driver. This will allow us to
spend less time in hardirq context.

Signed-off-by: Felipe Balbi <balbi@ti.com>
[Trivial formating changes]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:56 +02:00
Shubhrajyoti D d741d0c792 i2c: omap: remove redundant status read
Currently omap_i2c_ack_stat doesn't use the stat variable.
After the read of the I2C_STAT_REG it is not used.
Remove the redundant read of the status register.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:48 +02:00
Felipe Balbi b07be0f3b9 i2c: omap: get rid of the "complete" label
we can ack stat and complete the command from
the errata handling itself.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:41 +02:00
Felipe Balbi dd74548dde i2c: omap: resize fifos before each message
This patch will try to avoid the usage of
draining feature by reconfiguring the FIFO
the start condition of each message based
on the message's size.

By doing that, we will be better utilizing
the FIFO when doing big transfers.

While at that also drop the now unneeded
check for dev->buf_len as we always know
the amount of data to be transmitted.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:34 +02:00
Felipe Balbi 4a7ec4eda5 i2c: omap: simplify IRQ exit path
instead of having multiple return points, use
a goto statement to make that clearer.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:26 +02:00
Felipe Balbi 6a85ced2cf i2c: omap: always return IRQ_HANDLED
Always return IRQ_HANDLED otherwise we could get our IRQ line disabled due
to many spurious IRQs.

Signed-off-by: Felipe Balbi <balbi@ti.com>
[Trivial changes to commitlogs]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:19 +02:00
Felipe Balbi 3ff4443f88 i2c: omap: simplify errata check
omap_i2c_dev is allocated with kzalloc(),
so we need not initialize b_hw to zero.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:12 +02:00
Felipe Balbi 079d8af24b i2c: omap: bus: add a receiver flag
that way we can ignore TX IRQs while in receiver
mode and ignore RX IRQs while in transmitter mode.

Signed-off-by: Felipe Balbi <balbi@ti.com>
[Remove unnecessary braces]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:03:05 +02:00