Commit Graph

134 Commits

Author SHA1 Message Date
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-König" <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
Felipe Balbi ac79e4b249 i2c: omap: switch to platform_get_irq()
that's a nice helper from drivers core which
will give us the exact IRQ number, instead
of a pointer to an IRQ resource.

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 15:02:57 +02:00
Felipe Balbi 1d7afc9594 i2c: omap: ack IRQ in parts
According to flow diagrams on OMAP TRMs,
we should ACK the IRQ as they happen.

Signed-off-by: Felipe Balbi <balbi@ti.com>
[Ack the stat OMAP_I2C_STAT_AL in case of arbitration lost]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:02:50 +02:00
Felipe Balbi 66b9298878 i2c: omap: switch over to do {} while loop
this will make sure that we execute at least once.
No functional changes otherwise.

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 15:02:43 +02:00
Felipe Balbi 3312d25e1a i2c: omap: re-factor receive/transmit data loop
re-factor the common parts to a separate function,
so that code is easier to read and understand.

No functional changes.

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 15:02:36 +02:00
Felipe Balbi 4151e74177 i2c: omap: improve i462 errata handling
Make it not depend on ISR's local variables
in order to make it easier to re-factor the
transmit data loop.
Also since we are waiting for XUDF(Transmitter underflow) just before
writing data lets not flag the underflow.
This is anyways going to go once we write
the data.

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 15:02:28 +02:00
Felipe Balbi 6d9939f651 i2c: omap: split out [XR]DR and [XR]RDY
While they do pretty much the same thing, there
are a few peculiarities. Specially WRT erratas,
it's best to split those out and re-factor the
read/write loop to another function which both
cases call.

This last part will be done on another patch.

While at that, also avoid an unncessary register
read since dev->fifo_len will always contain the
correct amount of data 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 15:02:21 +02:00
Felipe Balbi 540a4790f7 i2c: omap: simplify omap_i2c_ack_stat()
stat & BIT(1) is the same as BIT(1), so let's
simplify things a bit by removing "stat &" from
all omap_i2c_ack_stat() calls.

Code snippet (extremely simplified):

if (stat & NACK) {
        ...
        omap_i2c_ack_stat(dev, stat & NACK);
}

if (stat & RDR) {
        ...
        omap_i2c_ack_stat(dev, stat & RDR);
}

and so on. The tricky place is only WRT errata handling, for example:

if (*stat & (NACK | AL)) {
        omap_i2c_ack_stat(dev, *stat & (XRDY | XDR));
        ...
}

but in this case, the errata says we must clear XRDY and XDR if that
errata triggers, so if they just got enabled or not, it doesn't matter.

Another tricky place is RDR | RRDY (likewise for XDR | XRDY):

if (stat & (RDR | RRDY)) {
        ...
        omap_i2c_ack_stat(dev, stat & (RDR | RRDY));
}

again here there will be no issues because those IRQs never fire
simultaneously and one will only after after we have handled the
previous, that's because the same FIFO is used anyway and we won't shift
data into FIFO until we tell the IP "hey, I'm done with the FIFO, you
can shift more data"

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
[Added the explaination from the discurssion to the commit logs]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:02:14 +02:00
Felipe Balbi c55edb9902 i2c: omap: add blank lines
trivial patch to aid readability. No functional
changes.

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 15:02:06 +02:00
Felipe Balbi 2049b5bcdd i2c: omap: decrease indentation level on data handling
The patch intends to decrease the indentation level on the
data handling
by using the fact that else of if (dev->buf_len) is same as
if (!dev->buf_len)

if (dev->buf_len) {
	aaa;
} else {
	bbb;
	break;
}

to

if (!dev->buf_len) {
        bbb;
        break;
}
aaa;

Hence no functional changes.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:01:59 +02:00
Felipe Balbi baf3d7b721 i2c: omap: simplify num_bytes handling
trivial patch, no functional changes

If the fifo is disabled or fifo_size is 0 the num_bytes
is set to 1. Else it is set to fifo_size or in case of a
draining interrupt the remaining bytes in the buff stat.
So the zero check is redundant and can be safely optimised.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-09-12 15:01:52 +02:00
Felipe Balbi d9ebd04d34 i2c: omap: switch to devm_* API
that helps deleting some boiler plate code
and lets driver-core manage our resources
for us.

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 15:01:45 +02:00
Uwe Kleine-König c4dba0119b i2c/i2c-omap: add a const qualifier
This prepares *of_device_id.data becoming const. Without this change
the following warning would occur:

	drivers/i2c/busses/i2c-omap.c: In function 'omap_i2c_probe':
	drivers/i2c/busses/i2c-omap.c:1025: warning: assignment discards qualifiers from pointer target type

Reviewed-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2012-09-11 08:56:47 +02:00
Kevin Hilman 33ec5e818b I2C: OMAP: xfer: fix runtime PM get/put balance on error
In omap_i2c_xfer(), ensure pm_runtime_put() is called, even on
failure.

Without this, after a failed xfer, the runtime PM usecount will have
been incremented, but not decremented causing the usecount to never
reach zero after a failure.  This keeps the device always runtime PM
enabled which keeps the enclosing power domain active, and prevents
full-chip retention/off from happening during idle.

Signed-off-by: Kevin Hilman <khilman@ti.com>
Reviewed-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-08-18 10:11:44 +02:00
Linus Torvalds a410963ba4 Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull embedded i2c changes from Wolfram Sang:
 "Changes for the "embedded" part of the I2C subsystem:

   - lots of devicetree conversions of drivers (and preparations for
     that)
   - big cleanups for drivers for OMAP, Tegra, Nomadik, Blackfin
   - Rafael's struct dev_pm_ops conversion patches for I2C
   - usual driver cleanups and fixes

  All patches have been in linux-next for an apropriate time and all
  patches touching files outside of i2c-folders should have proper acks
  from the maintainers."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (60 commits)
  Revert "i2c: tegra: convert normal suspend/resume to *_noirq"
  I2C: MV64XYZ: Add Device Tree support
  i2c: stu300: use devm managed resources
  i2c: i2c-ocores: support for 16bit and 32bit IO
  V4L/DVB: mfd: use reg_shift instead of regstep
  i2c: i2c-ocores: Use reg-shift property
  i2c: i2c-ocores: DT bindings and minor fixes.
  i2c: mv64xxxx: remove EXPERIMENTAL tag
  i2c-s3c2410: Use plain pm_runtime_put()
  i2c: s3c2410: Fix pointer type passed to of_match_node()
  i2c: mxs: Set I2C timing registers for mxs-i2c
  i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
  i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
  i2c:i2c-bfin-twi: include twi head file
  i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
  i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
  i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
  i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
  i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
  i2c-mv64xxxx: allow more than one driver instance
  ...

Conflicts:
	drivers/i2c/busses/i2c-nomadik.c
2012-07-28 13:43:12 -07:00
Laurent Pinchart fb604a3d58 i2c-omap: Add support for I2C_M_STOP message flag
Generate a stop condition after each message marked with I2C_M_STOP.

[JD: Add I2C_FUNC_PROTOCOL_MANGLING.]

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Jon Hunter f518b482c8 i2c: omap: Correct I2C revision for OMAP3
The OMAP3530 is based upon the same silicon as the OMAP3430 and so the I2C
revision is the same for 3430 and 3530. However, the OMAP3630 device has the
same I2C revision as OMAP4. Correct the revision definition to reflect this.

This patch is based on work done by Jon Hunter <jon-hunter@ti.com>
Changes from his patch
- Update OMAP_I2C_REV_ON_3430 also to reflect that it is same as 3530

Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-12 14:18:27 +02:00
Shubhrajyoti D 0e33bbb254 i2c: omap: Do not initialise the completion everytime
Use INIT_COMPLETION instead of init_completion in 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>
2012-07-12 14:18:26 +02:00
Shubhrajyoti D 5692d2a22e i2c: omap: Use SET_RUNTIME_PM_OPS
Use SET_RUNTIME_PM_OPS macro to set runtime functions.

Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-12 14:18:26 +02:00
Shubhrajyoti D d790aea70d i2c: omap: Annotate the remove code
The omap_i2c_remove function may not be needed after
device exit so the memory could be freed.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-12 14:18:17 +02:00
Neil Brown b4fde5e7ed I2C: OMAP: Fix timeout problem during suspend.
On a board with OMAP3 processor and TWL4030 Power management,
we need to talk to the TWL4030 during late suspend but cannot
because the I2C interrupt is disabled (as late suspend disables
interrupt).

e.g. I get messages like:

[   62.161102] musb-omap2430 musb-omap2430: LATE power domain suspend
[   63.167205] omap_i2c omap_i2c.1: controller timed out
[   63.183044] twl: i2c_read failed to transfer all messages
[   64.182861] omap_i2c omap_i2c.1: controller timed out
[   64.198455] twl: i2c_write failed to transfer all messages
[   65.198455] omap_i2c omap_i2c.1: controller timed out
[   65.203765] twl: i2c_write failed to transfer all messages

The stack shows omap2430_runtime_suspend calling twl4030_set_suspend
which tries to power-down the USB PHY (twl4030_phy_suspend ->
twl4030_phy_power -> __twl4030_phy_power which as a nice WARN_ON
that helps).

Then we get the same in resume:

[   69.603912] musb-omap2430 musb-omap2430: EARLY power domain resume
[   70.610473] omap_i2c omap_i2c.1: controller timed out
[   70.626129] twl: i2c_write failed to transfer all messages
etc.

So don't disable interrupts for I2C.

Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:15 +02:00
Shubhrajyoti D c8db38f0e1 I2C: OMAP: Rename the 1p153 to the erratum id i462
The section number in the recent errata document has changed.
Rename the erratum 1p153 to the unique id i462 instead, so that
it is easier to reference. Also change the function name and comments
to reflect the same.

Cc: Jon Hunter <jon-hunter@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:15 +02:00
Shubhrajyoti D e7e62df09d I2C: OMAP: Do not set the XUDF(Transmit underflow) if the underflow is not reached
Currently in the 1.153 errata handling, while waiting for transmitter
underflow, if NACK is got the XUDF(Transmit underflow) flag is also set.
Fix this by setting the XUDF(Transmit underflow) flag after wait for the
condition is over.

Cc: Alexander Shishkin <virtuoso@slind.org>
Acked-by: Moiz Sonasath <m-sonasath@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:14 +02:00
Tasslehoff Kjappfot 9aa8ec676b I2C: OMAP: prevent the overwrite of the errata flags
i2c_probe set the dev->errata flag, but omap_i2c_init cleared the flag again.
Prevent the overwrite of the errata flags.Move the errata handling to a unified
place in probe to prevent such errors.

Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tasslehoff Kjappfot <tasskjapp@gmail.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:14 +02:00
Shubhrajyoti D 3b0fb97c8d I2C: OMAP: Handle error check for pm runtime
If PM runtime get_sync fails return with the error
so that no further reads/writes goes through the interface.
This will avoid possible abort. Add a error message in case
of failure with the cause of the failure.

Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:14 +02:00
Shubhrajyoti D 0861f43089 I2C: OMAP: Fix the crash in i2c remove
In omap_i2c_remove we are accessing the I2C_CON register without
    enabling the clocks. Fix the same by ensure device is accessible by calling
    pm_runtime_get_sync before accessing the registers and calling pm_runtime_put
    after accessing.

    This fixes the following crash.
    [  154.723022] ------------[ cut here ]------------
    [  154.725677] WARNING: at arch/arm/mach-omap2/omap_l3_noc.c:112 l3_interrupt_handler+0x1b4/0x1c4()
    [  154.725677] L3 custom error: MASTER:MPU TARGET:L4 PER2
    [  154.742614] Modules linked in: i2c_omap(-)
    [  154.746948] Backtrace:
    [  154.746948] [<c0013078>] (dump_backtrace+0x0/0x110) from [<c026c158>] (dump_stack+0x18/0x1c)
    [  154.752716]  r6:00000070 r5:c002c43c r4:df9b9e98 r3:df9b8000
    [  154.764465] [<c026c140>] (dump_stack+0x0/0x1c) from [<c0041a2c>] (warn_slowpath_common+0x5c/0x6c)
    [  154.768341] [<c00419d0>] (warn_slowpath_common+0x0/0x6c) from [<c0041ae0>] (warn_slowpath_fmt+0x38/0x40)
    [  154.776153]  r8:00000180 r7:c0361594 r6:c0379b48 r5:00080003 r4:e0838b00
    [  154.790771] r3:00000009
    [  154.791778] [<c0041aa8>] (warn_slowpath_fmt+0x0/0x40) from [<c002c43c>] (l3_interrupt_handler+0x1b4/0x1c4)
    [  154.803710]  r3:c0361598 r2:c02ef74c
    [  154.807403] [<c002c288>] (l3_interrupt_handler+0x0/0x1c4) from [<c0085f44>] (handle_irq_event_percpu+0x58/0
    [  154.818237]  r8:0000002a r7:00000000 r6:00000000 r5:df808054 r4:df8893c0
    [  154.825378] [<c0085eec>] (handle_irq_event_percpu+0x0/0x188) from [<c00860b8>] (handle_irq_event+0x44/0x64)
    [  154.835662] [<c0086074>] (handle_irq_event+0x0/0x64) from [<c0088ec0>] (handle_fasteoi_irq+0xa4/0x10c)
    [  154.845458]  r6:0000002a r5:df808054 r4:df808000 r3:c034a150
    [  154.846466] [<c0088e1c>] (handle_fasteoi_irq+0x0/0x10c) from [<c0085ed0>] (generic_handle_irq+0x30/0x38)
    [  154.854278]  r5:c034aa48 r4:0000002a
    [  154.862091] [<c0085ea0>] (generic_handle_irq+0x0/0x38) from [<c000fd38>] (handle_IRQ+0x60/0xc0)
    [  154.874450]  r4:c034ea70 r3:000001f8
    [  154.878234] [<c000fcd8>] (handle_IRQ+0x0/0xc0) from [<c0008478>] (gic_handle_irq+0x20/0x5c)
    [  154.887023]  r7:ffffff40 r6:df9b9fb0 r5:c034e2b4 r4:0000001a
    [  154.887054] [<c0008458>] (gic_handle_irq+0x0/0x5c) from [<c000ea80>] (__irq_usr+0x40/0x60)
    [  154.901153] Exception stack(0xdf9b9fb0 to 0xdf9b9ff8)
    [  154.907104] 9fa0:                                     beaf1f04 4006be00 0000000f 0000000c
    [  154.915710] 9fc0: 4006c000 00000000 00008034 ffffff40 00000007 00000000 00000000 0007b8d7
    [  154.916778] 9fe0: 00000000 beaf1b68 0000d23c 4005baf0 80000010 ffffffff
    [  154.931335]  r6:ffffffff r5:80000010 r4:4005baf0 r3:beaf1f04
    [  154.937316] ---[ end trace 1b75b31a2719ed21 ]--

Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Linux PM list <linux-pm@vger.kernel.org>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-07-08 12:49:14 +02:00