Commit Graph

125 Commits

Author SHA1 Message Date
Wolfram Sang df576beee5 i2c: rcar: clean up after refactoring i2c_timings
The pointer is not really needed anymore since we have the timings
struct available in the function itself now. Remove the pointer and
access the struct directly.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-31 17:34:29 +02:00
Andy Shevchenko 38a592e266 i2c: rcar: Consolidate timings calls in rcar_i2c_clock_calculate()
Move i2c_parse_fw_timings() to rcar_i2c_clock_calculate() to consolidate
timings calls in one place.

While here, replace hard coded values with standard bus frequency definitions.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-24 21:59:33 +01:00
Andy Shevchenko 263a5646d8 i2c: core: Allow override timing properties with 0
Some drivers may allow to override properties with 0 value when defaults
are not in use, thus, replace memset() with corresponding per property
update.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-24 21:59:10 +01:00
Geert Uytterhoeven c39511ffb9 i2c: rcar: Remove superfluous call to clk_get_rate()
Variable "rate" already contains the current clock rate, so use that
rather than calling clk_get_rate() again.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-14 21:31:39 +01:00
Wolfram Sang 7b814d852a i2c: rcar: avoid race when unregistering slave client
After we disabled interrupts, there might still be an active one
running. Sync before clearing the pointer to the slave device.

Fixes: de20d1857d ("i2c: rcar: add slave support")
Reported-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-08-14 14:49:36 +02:00
Wolfram Sang 94e290b0e9 i2c: rcar: wait for data empty before starting DMA
When sending with DMA, the driver transfers the first byte with PIO (as
documented). However, it started DMA right after the first byte was
written. This worked, but was not according to the datasheet which
suggests to wait until data register was empty again. Implement this.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20 18:19:20 +01:00
Wolfram Sang 03f85e380f i2c: rcar: let DMA enable routine return success status
We will need to know if enabling DMA was successful in a later patch.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20 18:19:07 +01:00
Wolfram Sang ed5a81046b i2c: rcar: sanity check for minimal DMA length
Use a macro for the hardcoded value and apply a build check. If it is
not met, the driver logic will not work anymore.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20 18:18:54 +01:00
Wolfram Sang 7ce98a5591 i2c: rcar: explain the lockless design
To make sure people can understand the lockless design of this driver
without the need to dive into git history, add a comment giving an
overview of the situation.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12 14:09:33 +01:00
Hiromitsu Yamasaki a35ba2f74d i2c: rcar: fix concurrency issue related to ICDMAER
This patch fixes the problem that an interrupt may set up a new I2C
message and the DMA callback overwrites this setup.

By disabling the DMA Enable Register(ICDMAER), rcar_i2c_dma_unmap()
enables interrupts for register settings (such as Master Control
Register(ICMCR)) and advances the I2C transfer sequence.

If an interrupt occurs immediately after ICDMAER is disabled, the
callback handler later continues and overwrites the previous settings
from the interrupt. So, disable ICDMAER at the end of the callback to
ensure other interrupts are masked until then.

Note that this driver needs to work lock-free because there are IP cores
with a HW race condition which prevent us from using a spinlock in the
interrupt handler.

Reproduction test:
1. Add a delay after disabling ICDMAER. (It is expected to generate an
   interrupt of rcar_i2c_irq())

    void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv)
    {
        ...
        rcar_i2c_write(priv, ICDMAER, 0);
        usleep_range(500, 800)
        ...
        priv->dma_direction = DMA_NONE;
    }

2. Execute DMA transfers

 $ i2ctransfer -y 4 w9@0x6a 1 1+ r16

3. A log message of BUG_ON() will be displayed.

Fixes: 73e8b05283 ("i2c: rcar: add DMA support")
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: updated test case to be more reliable, added note to comment]
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12 14:09:16 +01:00
Wolfram Sang 18769445ca i2c: rcar: refactor TCYC handling
The latest documentation made it clear that we need to initialize the
TCYC value independently of DMA. The old code used TCYC06 (wrongly) for
non-DMA transfers. The new code sets TCYC up independently from DMA.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08 22:30:46 +01:00
Wolfram Sang d0051ca584 i2c: rcar: comment maintenance
Update copyright years and remove a comment which grew incorrect and
useless over time.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05 14:31:55 +01:00
Geert Uytterhoeven 81d696c7c4 i2c: rcar: Fix clients using i2c from suspend callback
When doing s2idle/s2ram on Salvator-X(S):

    WARNING: CPU: 2 PID: 971 at drivers/i2c/i2c-core-base.c:1869 __i2c_transfer+0x608/0x910
[...]
    Call trace:
     __i2c_transfer+0x608/0x910
     i2c_smbus_xfer_emulated+0x158/0x5b0
     __i2c_smbus_xfer+0x17c/0x818
     i2c_smbus_xfer+0x64/0x98
     i2c_smbus_read_byte_data+0x40/0x70
     cs2000_bset.isra.1+0x2c/0x68
     __cs2000_set_rate.constprop.7+0x80/0x148
     cs2000_resume+0x18/0x20
     dpm_run_callback+0x74/0x330
     device_resume_early+0xd4/0x120
     dpm_resume_early+0x158/0x4f8
     suspend_devices_and_enter+0x36c/0xd98
[...]

On second resume, the sound driver fails with:

    cs2000-cp 2-004f: pll lock failed
    rcar_sound ec500000.sound: can't use clk 1

As the CS2000 clock driver needs to send I2C messages during suspend,
the I2C controller driver should be suspended later, and resumed
earlier.  Fix this by using the noirq sleep ops instead of the normal
sleep ops, which are called after the late sleep ops, as used by the
CS2000 clock driver.

Fixes: 18569fa89a ("i2c: rcar: add suspend/resume support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-22 23:55:08 +01:00
Wolfram Sang 18569fa89a i2c: rcar: add suspend/resume support
Because the adapter will be set up before every transaction anyhow, we
just need to mark it as suspended to the I2C core.

Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:52 +01:00
Wolfram Sang 0b57436f15 i2c: rcar: check bus state before reinitializing
We should check the bus state before reinitializing the IP core.
Otherwise, the internal bus busy state which also tracks multi-master
activity is lost.

Credits go to the Renesas BSP team for suggesting this change.

Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Fixes: ae481cc139 ("i2c: rcar: fix resume by always initializing registers before transfer")
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-11-27 14:00:36 +01:00
Wolfram Sang 31d86033a0 i2c: rcar: cleanup DMA for all kinds of failure
DMA needs to be cleaned up not only on timeout, but on all errors where
it has been setup before.

Fixes: 73e8b05283 ("i2c: rcar: add DMA support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-10-20 15:25:59 +02:00
Wolfram Sang 6055af5e1c i2c: use SPDX identifier for Renesas drivers
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24 14:49:36 +02:00
Wolfram Sang 19358d4488 i2c: rcar: implement STOP and REP_START according to docs
When doing a REP_START after a read message, the driver used to trigger
a STOP first which would then be overwritten by REP_START. This was the
only stable method found when doing the last refactoring. However, this
was not in accordance with the documentation.

After research from our BSP team and myself, we now can implement a
version which works and is according to the documentation. The new
approach ensures the ICMCR register is only changed when really needed.

Tested on a R-Car Gen2 (H2) and Gen3 with DMA (M3N).

Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-20 14:49:41 +02:00
Wolfram Sang b07531acd5 i2c: rcar: refactor private flags
Use BIT macro to avoid shift-31-problem, indent a little more and use
GENMASK to make it easier to add new flags.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-20 14:49:24 +02:00
Wolfram Sang 3ef3e5cd72 i2c: rcar: use core to detect 'no zero length' quirk
And don't reimplement in the driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-04 23:25:07 +02:00
Wolfram Sang 3b770017b0 i2c: rcar: handle RXDMA HW behaviour on Gen3
On Gen3, we can only do RXDMA once per transfer reliably. For that, we
must reset the device, then we can have RXDMA once. This patch
implements this. When there is no reset controller or the reset fails,
RXDMA will be blocked completely. Otherwise, it will be disabled after
the first RXDMA transfer. Based on a commit from the BSP by Hiromitsu
Yamasaki, yet completely refactored to handle multiple read messages
within one transfer.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-23 20:10:56 +02:00
Wolfram Sang 4fe10de535 i2c: rcar: use the new get_bus_free callback
To break out of recovery as early as possible, feed back the bus_free
logic state.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-17 10:47:53 +02:00
Peter Rosin 30a6475744 i2c: busses: make use of i2c_8bit_addr_from_msg
Because it looks neater.

For diolan, this allows factoring out some code that is now common
between if and else.

For eg20t, pch_i2c_writebytes is always called with a write in
msgs->flags, and pch_i2c_readbytes with a read.

For imx, i2c_imx_dma_write and i2c_imx_write are always called with a
write in msgs->flags, and i2c_imx_read with a read.

For qup, qup_i2c_write_tx_fifo_v1 is always called with a write in
qup->msg->flags.

For stu300, also restructure debug output for resends, since that
code as a result is only handling debug output.

Reviewed-by: Guenter Roeck <linux@roeck-us.net> [diolan]
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [efm32 and imx]
Acked-by: Linus Walleij <linus.walleij@linaro.org> [stu300]
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-29 20:30:49 +02:00
Wolfram Sang b1437dcb97 i2c: rcar: enhance comment to avoid regressions
Give a clear testcase for people wishing to change this code. It is also
a reminder for me if people ask about it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30 11:14:35 +02:00
Hiromitsu Yamasaki a1de3253a8 i2c: rcar: fix mask value of prohibited bit
According to documentation, Bit 7 of ICMSR is unused and 0 should be
written to it. Fix the mask accordingly.

Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[wsa: edited commit message]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24 14:04:38 +01:00
Wolfram Sang fe34fbf93f i2c: rcar: fix some trivial typos in comments
Nothing big, but they get annoying after a while ;)

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-24 07:16:34 +01:00
Wolfram Sang 7d2c17f021 i2c: rcar: implement bus recovery
We can force levels of SCL and SDA, so we can use that for bus recovery.
Note that we cannot read SDA back, because we will only get the internal
state of the bus free detection.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-16 00:04:48 +01:00
Wolfram Sang adbd77b589 i2c: rcar: skip DMA if buffer is not safe
This HW is prone to races, so it needs to setup new messages in irq
context. That means we can't alloc bounce buffers if a message buffer is
not DMA safe. So, in that case, simply fall back to PIO.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03 21:25:00 +01:00
Eugeniu Rosca 8ae034c2ca i2c: rcar: avoid unused ret variable
Fix smatch warning:
drivers/i2c/busses/i2c-rcar.c:628 \
  rcar_i2c_request_dma_chan() warn: unused return: ret = PTR_ERR()

Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-17 21:52:36 +02:00
Linus Torvalds 235b84fc86 Merge branch 'i2c/for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "This pull request contains:

   - i2c core reorganization. One source file became too monolithic. It
     is now split up, yet we still have the same named object as the
     final output. This should ease maintenance.

   - new drivers: ZTE ZX2967 family, ASPEED 24XX/25XX

   - designware driver gained slave mode support

   - xgene-slimpro driver gained ACPI support

   - bigger overhaul for pca-platform driver

   - the algo-bit module now supports messages with enforced STOP

   - slightly bigger than usual set of driver updates and improvements

  and with much appreciated quality assurance from Andy Shevchenko"

* 'i2c/for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (51 commits)
  i2c: Provide a stub for i2c_detect_slave_mode()
  i2c: designware: Let slave adapter support be optional
  i2c: designware: Make HW init functions static
  i2c: designware: fix spelling mistakes
  i2c: pca-platform: propagate error from i2c_pca_add_numbered_bus
  i2c: pca-platform: correctly set algo_data.reset_chip
  i2c: acpi: Do not create i2c-clients for LNXVIDEO ACPI devices
  i2c: designware: enable SLAVE in platform module
  i2c: designware: add SLAVE mode functions
  i2c: zx2967: drop COMPILE_TEST dependency
  i2c: zx2967: always use the same device when printing errors
  i2c: pca-platform: use dev_warn/dev_info instead of printk
  i2c: pca-platform: use device managed allocations
  i2c: pca-platform: add devicetree awareness
  i2c: pca-platform: switch to struct gpio_desc
  dt-bindings: add bindings for i2c-pca-platform
  i2c: cadance: fix ctrl/addr reg write order
  i2c: zx2967: add i2c controller driver for ZTE's zx2967 family
  dt: bindings: add documentation for zx2967 family i2c controller
  i2c: algo-bit: add support for I2C_M_STOP
  ...
2017-07-12 10:04:56 -07:00
Wolfram Sang b395ba2169 i2c: rcar: document HW incapabilities
Add recent findings (IGNORE_NAK) and document in a bit more detail why
the feature is not possible.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-23 20:30:46 +02:00
Wolfram Sang 5c8e3ab146 i2c: use proper name for the R-Car SoC
It is 'R-Car', not 'RCar'. No code or binding changes, only descriptive text.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-19 16:24:05 +02:00
Wolfram Sang 916335036d i2c: rcar: use correct length when unmapping DMA
Because we need to transfer some bytes with PIO, the msg length is not
the length of the DMA buffer. Use the correct value which we used when
doing the mapping.

Fixes: 73e8b05283 ("i2c: rcar: add DMA support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-15 15:51:44 +02:00
Wolfram Sang 63a761eef5 i2c: rcar: clarify PM handling with more comments
PM handling is correct but might be a bit subtle. Add some comments for
clarification.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-21 14:08:57 +02:00
Wolfram Sang ae481cc139 i2c: rcar: fix resume by always initializing registers before transfer
Resume failed because of uninitialized registers. Instead of adding a
resume callback, we simply initialize registers before every transfer.
This lightweight change is more robust and will keep us safe if we ever
need support for power domains or dynamic frequency changes.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-21 14:08:52 +02:00
Simon Horman ad4a8dc3fe i2c: rcar: Add per-Generation fallback bindings
In the case of Renesas R-Car hardware we know that there are generations of
SoCs, e.g. Gen 2 and Gen 3. But beyond that it's not clear what the
relationship between IP blocks might be. For example, I believe that
r8a7790 is older than r8a7791 but that doesn't imply that the latter is a
descendant of the former or vice versa.

We can, however, by examining the documentation and behaviour of the
hardware at run-time observe that the current driver implementation appears
to be compatible with the IP blocks on SoCs within a given generation.

For the above reasons and convenience when enabling new SoCs a
per-generation fallback compatibility string scheme is being adopted for
drivers for Renesas SoCs.

Also:
* Deprecate renesas,i2c-rcar. It seems poorly named as it is only
  compatible with R-Car Gen 1. It also appears unused in mainline.
* Add some text to describe per-SoC bindings

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-12-11 22:48:53 +01:00
Linus Torvalds 87840a2b7e Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Here is the 4.9 pull request from I2C including:

   - centralized error messages when registering to the core
   - improved lockdep annotations to prevent false positives
   - DT support for muxes, gates, and arbitrators
   - bus speeds can now be obtained from ACPI
   - i2c-octeon got refactored and now supports ThunderX SoCs, too
   - i2c-tegra and i2c-designware got a bigger bunch of updates
   - a couple of standard driver fixes and improvements"

* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
  i2c: axxia: disable clks in case of failure in probe
  i2c: octeon: thunderx: Limit register access retries
  i2c: uniphier-f: fix misdetection of incomplete STOP condition
  gpio: pca953x: variable 'id' was used twice
  i2c: i801: Add support for Kaby Lake PCH-H
  gpio: pca953x: fix an incorrect lockdep warning
  i2c: add a warning to i2c_adapter_depth()
  lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
  i2c: export i2c_adapter_depth()
  i2c: rk3x: Fix variable 'min_total_ns' unused warning
  i2c: rk3x: Fix sparse warning
  i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
  i2c: octeon: Fix high-level controller status check
  i2c: octeon: Avoid sending STOP during recovery
  i2c: octeon: Fix set SCL recovery function
  i2c: rcar: add support for r8a7796 (R-Car M3-W)
  i2c: imx: make bus recovery through pinctrl optional
  i2c: meson: add gxbb compatible string
  i2c: uniphier-f: set the adapter to master mode when probing
  i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
  ...
2016-10-07 14:12:21 -07:00
Ulrich Hecht c13f743aee i2c: rcar: add support for r8a7796 (R-Car M3-W)
Same as r8a7795.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-16 19:46:10 +02:00
Wolfram Sang c13c29186c i2c: rcar: use proper device with dma_mapping_error
We must use the same device we used for mapping.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-25 18:48:47 +02:00
Wolfram Sang ea734404f3 i2c: don't print error when adding adapter fails
The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22 08:19:55 +02:00
Niklas Söderlund 6aabf9d01f i2c: rcar: use dma_request_chan()
New drivers should not use dma_request_slave_channel_reason() but
dma_request_chan(). The former is a macro to the later so this change do
not effect the driver in any way.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-26 20:43:06 +02:00
Niklas Söderlund 73e8b05283 i2c: rcar: add DMA support
Make it possible to transfer i2c message buffers via DMA.
Start/Stop/Sending_Slave_Address and some data is still handled using
the old state machine, it is sending the bulk of the data that is done
via DMA.

The first byte of a transmission and the last two bytes of reception are
sent/received using PIO. This is needed for the HW to have access to the
first byte before DMA transmit and to be able to set the STOP condition
for DMA reception.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: fixed a checkpatch warning]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-15 08:52:49 +02:00
Wolfram Sang 69e558fa35 i2c: rcar: don't open code of_device_get_match_data()
This change will also make Coverity happy by avoiding a theoretical NULL
pointer dereference; yet another reason is to use the above helper function
to tighten the code and make it more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-03-03 22:25:23 +01:00
Linus Torvalds 32250e4a5f Merge branch 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Quite some driver updates:
   - piix4 can now handle multiplexed adapters
   - brcmstb, xlr, eg20t, designware drivers support more SoCs
   - emev2 gained i2c slave support
   - img-scb and rcar got bigger refactoring to remove issues
   - lots of common driver updates

  i2c core changes:
   - new quirk flag when an adapter does not support clock stretching,
     so clients can be configured to avoid that if possible
   - added a helper function to retrieve timing parameters from firmware
     (with rcar being the first user)
   - "multi-master" DT binding added so drivers can adapt to this
     setting (like disabling PM to keep arbitration working)
   - RuntimePM for the logical adapter device is now always enabled by
     the core to ensure propagation from childs to the parent (the HW
     device)
   - new macro builtin_i2c_driver to reduce boilerplate"

* 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
  i2c: create builtin_i2c_driver to avoid registration boilerplate
  i2c: imx: fix i2c resource leak with dma transfer
  dt-bindings: i2c: eeprom: add another EEPROM device
  dt-bindings: move I2C eeprom descriptions to the proper file
  i2c: designware: Do not require clock when SSCN and FFCN are provided
  DT: i2c: trivial-devices: Add Epson RX8010 and MPL3115
  i2c: s3c2410: remove superfluous runtime PM calls
  i2c: always enable RuntimePM for the adapter device
  i2c: designware: retry transfer on transient failure
  i2c: ibm_iic: rename i2c_timings struct due to clash with generic version
  i2c: designware: Add support for AMD Seattle I2C
  i2c: imx: Remove unneeded comments
  i2c: st: use to_platform_device()
  i2c: designware: use to_pci_dev()
  i2c: brcmstb: Adding support for CM and DSL SoCs
  i2c: mediatek: fix i2c multi transfer issue in high speed mode
  i2c: imx: improve code readability
  i2c: imx: Improve message log when DMA is not used
  i2c: imx: add runtime pm support to improve the performance
  i2c: imx: init bus recovery info before adding i2c adapter
  ...
2016-01-14 11:25:37 -08:00
Wolfram Sang 7ee24eb508 i2c: rcar: disable PM in multi-master mode
In multi master mode, the IP core needs to be always active for
arbitration reasons. Get the config from DT and set up PM depending on
the config.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:11:48 +01:00
Wolfram Sang 42c0783b89 i2c: rcar: remove macros dealing with flags
These macros don't really hide complexity, but C idioms. Removing them
makes the code easier to read IMO and make a planned extension easier.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:11:21 +01:00
Wolfram Sang b4cd08aa1f i2c: rcar: disable runtime PM correctly in slave mode
When we also are I2C slave, we need to disable runtime PM because the
address detection mechanism needs to be active all the time. However, we
can reenable runtime PM once the slave instance was unregistered. So,
use pm_runtime_get_sync/put to achieve this, since it has proper
refcounting. pm_runtime_allow/forbid is like a global knob controllable
from userspace which is unsuitable here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2015-12-19 12:00:37 +01:00
Wolfram Sang ca68eade66 i2c: rcar: honor additional i2c timings from DT
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:10 +01:00
Wolfram Sang c7881871de i2c: rcar: switch to i2c generic dt parsing
Switch to the new generic functions. Plain convert, no functionality
added yet.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:09 +01:00
Wolfram Sang f9c9d31bdd i2c: rcar: refactor probe function a little
The probe function is a little bit messy, something here, something
there. Rework it so that there is some order: first init the private
structure, then the adapter, then do HW init. This also allows us to
remove the device argument of the clock calculation function, because it
now can be deduced from the private structure. Also, shorten some lines
where possible. This is a preparation for further refactoring.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:51:08 +01:00