Commit Graph

3051 Commits

Author SHA1 Message Date
qii wang
0056a54b33 i2c: mediatek: remove completion_done()
Completion_done() is useless when we don't use its return value,
so we remove it.

Signed-off-by: qii wang <qii.wang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05 14:11:46 +01:00
qii wang
93caa0dab7 i2c: mediatek: speeds is replaced by macros definitions
Different speeds have been defined by macros,
so we use macros definitions.

Signed-off-by: qii wang <qii.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05 14:10:43 +01:00
Wolfram Sang
2f8aa465b9 i2c: gpio: sort includes
Less risk for duplications when adding new ones.

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 14:05:03 +01:00
Linus Walleij
cac28ac2a8 i2c: iop3xx: Add device tree probing
This adds device tree probing support for the IOP3xx
I2C master.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05 13:46:36 +01:00
Jae Hyun Yoo
44783efdfe i2c: aspeed: Remove hard-coded bus timeout value setting
This commit removes hard-coded bus timeout value setting so that
it can be set by i2c-core-base.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-23 00:18:11 +01:00
Wolfram Sang
9d899ed400 i2c: sh_mobile: update copyright and comments
Update copyright years and add Renesas to it. Add/update comments to
make driver easier to understand.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-23 00:18:10 +01:00
Wolfram Sang
63c5246003 i2c: sh_mobile: refactor rx isr
Remove the do_while loop which was just there to have an easy exit with
"break;" and replace it with if-else-blocks which should make the state
machine clearer.

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>
2019-01-23 00:18:09 +01:00
Wolfram Sang
0130e3bfa9 i2c: sh_mobile: replace break; with if-block
In preparation to remove the do-while-loop.

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>
2019-01-23 00:18:09 +01:00
Wolfram Sang
e659f36d46 i2c: sh_mobile: remove is_first_byte function
All state machines deal with pd->pos values. This helper function is an
exception and makes it only more confusing.

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>
2019-01-23 00:18:08 +01:00
Wolfram Sang
d16f2bfea3 i2c: sh_mobile: drop 'data' argument from i2c_op function
It is clear that we always send the address in TX_FIRST and data in TX.
No need to pass it from the caller.

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>
2019-01-23 00:18:08 +01:00
Wolfram Sang
1f32fbdfc1 i2c: sh_mobile: remove get_data function
It makes the code much easier comprehensible to explicitly code that the
first byte will be client address and all the following bytes are the
actual data.

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>
2019-01-23 00:18:07 +01:00
Wolfram Sang
5b3e3b43b0 i2c: sh_mobile: simplify sending address for RX
pd->pos won't be smaller than -1, so we can simplify the logic.

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>
2019-01-23 00:18:07 +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
YueHaibing
3d5b386849 i2c: imx: Fix inconsistent IS_ERR and PTR_ERR in i2c_imx_dma_request()
Change the call to PTR_ERR to access the value just tested by IS_ERR.

Fixes: 5b3a23a3cc ("i2c: imx: notify about real errors on dma i2c_imx_dma_request")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Esben Haabendal <esben@haabendal.dk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-22 23:53:03 +01:00
Oleksij Rempel
e1ab9a468e i2c: imx: improve the error handling in i2c_imx_dma_request()
Improve the error handling in i2c_imx_dma_request() and let it return an error
indication that the caller then can handle accordingly.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-15 22:54:00 +01:00
Oleksij Rempel
5b3a23a3cc i2c: imx: notify about real errors on dma i2c_imx_dma_request
At least on i.MX5x, the DMA events for I2C and SDHC use the same channel
and there can only be a single user. So in this case there should be no
message emitted that looks like an error if the I2C device doesn't have
an assigned DMA channel. In contrast real problems that were only
emitted at debug level before should be described at a higher level
to be better visible and so understandable.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-15 22:53:46 +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
2088716f90 i2c: s3c2410: use core helper to mark adapter suspended
Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:52 +01:00
Wolfram Sang
d5c95bd6f3 i2c: exynos5: use core helper to mark adapter suspended
Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:51 +01:00
Wolfram Sang
5a7b81ff1b i2c: sprd: use core helper to mark adapter suspended
Rejecting transfers should be handled by the core.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:50 +01:00
Wolfram Sang
7b6b69984e i2c: sprd: don't use pdev as variable name for struct device *
The pointer to a device is usually named 'dev'. These 'pdev' here look
much like copy&paste errors. Fix them to avoid confusion.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:50 +01:00
Wolfram Sang
5601df355b i2c: zx2967: use core helper to mark adapter suspended
Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version
and make sure resume mark is set after enabling clocks (not before).

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:49 +01:00
Wolfram Sang
f2e0d28cba i2c: brcmstb: use core helper to mark adapter suspended
Rejecting transfers should be handled by the core.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:49 +01:00
Wolfram Sang
1adcc83e21 i2c: synquacer: remove unused is_suspended flag
This flag was defined and checked but never set a value. Remove it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:02:48 +01:00
Linus Torvalds
7671c14e6a Merge branch 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "I2C has only driver updates for you this time.

  Mostly new IDs/DT compatibles, also SPDX conversions, small cleanups.
  STM32F7 got FastMode+ and PM support, Axxia some reliabilty
  improvements"

* 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (26 commits)
  i2c: Add Actions Semiconductor Owl family S700 I2C support
  dt-bindings: i2c: Add S700 support for Actions Semi Soc's
  i2c: ismt: Add support for Intel Cedar Fork
  i2c: tegra: Switch to SPDX identifier
  i2c: tegra: Add missing kerneldoc for some fields
  i2c: tegra: Cleanup kerneldoc comments
  i2c: axxia: support sequence command mode
  dt-bindings: i2c: rcar: Add r8a774c0 support
  dt-bindings: i2c: sh_mobile: Add r8a774c0 support
  i2c: sh_mobile: Add support for r8a774c0 (RZ/G2E)
  i2c: i2c-cros-ec-tunnel: Switch to SPDX identifier.
  i2c: powermac: Use of_node_name_eq for node name comparisons
  i2c-axxia: check for error conditions first
  i2c-axxia: dedicated function to set client addr
  dt-bindings: i2c: Use correct vendor prefix for Atmel
  i2c: tegra: replace spin_lock_irqsave with spin_lock in ISR
  eeprom: at24: add support for 24c2048
  dt-bindings: eeprom: at24: add "atmel,24c2048" compatible string
  i2c: i2c-stm32f7: add PM Runtime support
  i2c: sh_mobile: add support for r8a77990 (R-Car E3)
  ...
2019-01-05 18:13:35 -08:00
Parthiban Nallathambi
81482d13f3 i2c: Add Actions Semiconductor Owl family S700 I2C support
Add S700 to the list of devices supported by Owl I2C driver.

Add Actions Semiconductor Owl family S700 I2C driver.

Signed-off-by: Parthiban Nallathambi <pn@denx.de>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-03 20:36:18 +01:00
Jarkko Nikula
5cda2d86de i2c: ismt: Add support for Intel Cedar Fork
Add PCI ID for the Intel Cedar Fork iSMT SMBus controller.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
[wsa: kept sorting]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-03 20:02:32 +01:00
Thierry Reding
d6f0453391 i2c: tegra: Switch to SPDX identifier
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:37:53 +01:00
Thierry Reding
0604ee4aef i2c: tegra: Add missing kerneldoc for some fields
Not all fields were properly documented. Add kerneldoc for the missing
fields to prevent the build from flagging them.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:33:34 +01:00
Thierry Reding
c990bbafdb i2c: tegra: Cleanup kerneldoc comments
Some of the kerneldoc uses a strange spelling for abbreviations. Turn
them into all-uppercase and clean up some whitespace issues while at it.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:32:44 +01:00
Adamski, Krzysztof (Nokia - PL/Wroclaw)
3035a66934 i2c: axxia: support sequence command mode
In order to comply with SMBus specification, the Axxia I²C module will
abort the multi message transfer if the delay between finishing sending
one message and starting another is longer than 25ms. Unfortunately it
isn't that hard to trigger this situation on a busy system. In order to
fix this problem, we should make sure hardware does whole transaction
without waiting for software to fill some data.

Fortunately, in addition to Manual mode that is currently used by the
driver to perform I²C transfers, the module supports also so called
Sequence mode. In this mode, the module automatically performs
predefined sequence of operations - it sends a slave address, transmits
specified number of bytes from the FIFO, changes transfer direction,
resends the slave address and then reads specified number of bytes to
FIFO. While very inflexible, this does fit a most common case of multi
message transfer - the one where you first write a register number you
want to read and then read it.

To use this mode effectively, a number of conditions must be met to
ensure the transaction does fit the predefined sequence. In case this is
not the case, a fallback to manual mode is used.

The initialization of this mode is very similar to Manual mode. The most
notable difference is different bit in the Master Interrupt Status
designating finishing of transaction. Also some of the errors, like TSS,
cannot happen in this mode.

While it is possible to support transactions requesting a read of any
size (RFL interrupt will be generated when FIFO size is not enough) the
TFL interrupt is not available in this mode, thus the write part of the
transaction cannot exceed FIFO_SIZE (8).

Note that in case of a NAK during transaction, the NA/ND status bits
will be set before STOP command is generated, triggering an interrupt
while the controller is still busy. Current solution for this problem is
to actively wait for this command to stop before leaving xfer callback.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
[wsa: added braces around else branch spotted by checkpatch]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:28:50 +01:00
Fabrizio Castro
51243b7345 i2c: sh_mobile: Add support for r8a774c0 (RZ/G2E)
Similarly to R-Car E3, RZ/G2E doesn't come with automatic
transmission registers, as such it is not considered compatible
with the existing fallback bindings.

Add SoC specific binding compatibility to allow for later
support for automatic transmission.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.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>
2018-12-17 23:20:09 +01:00
Enric Balletbo i Serra
02d26b9a57 i2c: i2c-cros-ec-tunnel: Switch to SPDX identifier.
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:08:41 +01:00
Arnd Bergmann
32774a8153 i2c: nvidia-gpu: mark resume function as __maybe_unused
When CONFIG_PM is disabled, this is needed to avoid a harmless
unused-function warning:

drivers/i2c/busses/i2c-nvidia-gpu.c:345:12: error: 'gpu_i2c_resume' defined but not used [-Werror=unused-function]

Fixes: c71bcdcb42 ("i2c: add i2c bus driver for NVIDIA GPU")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-11 21:39:43 +01:00
Rob Herring
48f9c33c25 i2c: powermac: Use of_node_name_eq for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-11 21:16:28 +01:00
Adamski, Krzysztof (Nokia - PL/Wroclaw)
4f5c85fe3a i2c-axxia: check for error conditions first
It was observed that when using seqentional mode contrary to the
documentation, the SS bit (which is supposed to only be set if
automatic/sequence command completed normally), is sometimes set
together with NA (NAK in address phase) causing transfer to falsely be
considered successful.

My assumption is that this does not happen during manual mode since the
controller is stopping its work the moment it sets NA/ND bit in status
register. This is not the case in Automatic/Sequentional mode where it
is still working to send STOP condition and the actual status we get
depends on the time when the ISR is run.

This patch changes the order of checking status bits in ISR - error
conditions are checked first and only if none of them occurred, the
transfer may be considered successful. This is required to introduce
using of sequentional mode in next patch.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-11 20:59:17 +01:00
Adamski, Krzysztof (Nokia - PL/Wroclaw)
eb9907789a i2c-axxia: dedicated function to set client addr
This patch moves configuration of hardware registers used for setting
i2c client address to separate function. It is preparatory change for
next commit.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-11 20:58:59 +01:00
Wolfram Sang
66693960f5 Linux 4.20-rc6
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Merge tag 'v4.20-rc6' into i2c/for-5.0

Linux 4.20-rc6
2018-12-11 20:58:20 +01:00
jun qian
3782cc3725 i2c: tegra: replace spin_lock_irqsave with spin_lock in ISR
As you are already in ISR, it is unnecessary to call spin_lock_irqsave.

Signed-off-by: jun qian <hangdianqj@163.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-11 20:56:52 +01:00
Masahiro Yamada
ece27a337d i2c: uniphier-f: fix violation of tLOW requirement for Fast-mode
Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode,
tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us.

tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode:
  Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us
  Fast-mode:     tLOW = 1.39 us, tHIGH = 1.11 us

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:59 +01:00
Masahiro Yamada
8469636ab5 i2c: uniphier: fix violation of tLOW requirement for Fast-mode
Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode,
tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us.

tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode:
  Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us
  Fast-mode:     tLOW = 1.39 us, tHIGH = 1.11 us

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:59 +01:00
Masahiro Yamada
cd8843f541 i2c: uniphier-f: fill TX-FIFO only in IRQ handler for repeated START
- For a repeated START condition, this controller starts data transfer
   immediately after the slave address is written to the TX-FIFO.

 - Once the TX-FIFO empty interrupt is asserted, the controller makes
   a pause even if additional data are written to the TX-FIFO.

Given those circumstances, the data after a repeated START may not be
transferred if the interrupt is asserted while the TX-FIFO is being
filled up. A more reliable way is to append TX data only in the
interrupt handler.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:59 +01:00
Masahiro Yamada
c2a653deaa i2c: uniphier-f: fix timeout error after reading 8 bytes
I was totally screwed up in commit eaba68785c ("i2c: uniphier-f:
fix race condition when IRQ is cleared"). Since that commit, if the
number of read bytes is multiple of the FIFO size (8, 16, 24... bytes),
the STOP condition could be issued twice, depending on the timing.
If this happens, the controller will go wrong, resulting in the timeout
error.

It was more than 3 years ago when I wrote this driver, so my memory
about this hardware was vague. Please let me correct the description
in the commit log of eaba68785c.

Clearing the IRQ status on exiting the IRQ handler is absolutely
fine. This controller makes a pause while any IRQ status is asserted.
If the IRQ status is cleared first, the hardware may start the next
transaction before the IRQ handler finishes what it supposed to do.

This partially reverts the bad commit with clear comments so that I
will never repeat this mistake.

I also investigated what is happening at the last moment of the read
mode. The UNIPHIER_FI2C_INT_RF interrupt is asserted a bit earlier
(by half a period of the clock cycle) than UNIPHIER_FI2C_INT_RB.

I consulted a hardware engineer, and I got the following information:

UNIPHIER_FI2C_INT_RF
    asserted at the falling edge of SCL at the 8th bit.

UNIPHIER_FI2C_INT_RB
    asserted at the rising edge of SCL at the 9th (ACK) bit.

In order to avoid calling uniphier_fi2c_stop() twice, check the latter
interrupt. I also commented this because it is obscure hardware internal.

Fixes: eaba68785c ("i2c: uniphier-f: fix race condition when IRQ is cleared")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:59 +01:00
Hans de Goede
0544ee4b1a i2c: scmi: Fix probe error on devices with an empty SMB0001 ACPI device node
Some AMD based HP laptops have a SMB0001 ACPI device node which does not
define any methods.

This leads to the following error in dmesg:

[    5.222731] cmi: probe of SMB0001:00 failed with error -5

This commit makes acpi_smbus_cmi_add() return -ENODEV instead in this case
silencing the error. In case of a failure of the i2c_add_adapter() call
this commit now propagates the error from that call instead of -EIO.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:59 +01:00
Adamski, Krzysztof (Nokia - PL/Wroclaw)
6c7f25cae5 i2c: axxia: properly handle master timeout
According to Intel (R) Axxia TM Lionfish Communication Processor
Peripheral Subsystem Hardware Reference Manual, the AXXIA I2C module
have a programmable Master Wait Timer, which among others, checks the
time between commands send in manual mode. When a timeout (25ms) passes,
TSS bit is set in Master Interrupt Status register and a Stop command is
issued by the hardware.

The axxia_i2c_xfer(), does not properly handle this situation, however.
For each message a separate axxia_i2c_xfer_msg() is called and this
function incorrectly assumes that any interrupt might happen only when
waiting for completion. This is mostly correct but there is one
exception - a master timeout can trigger if enough time has passed
between individual transfers. It will, by definition, happen between
transfers when the interrupts are disabled by the code. If that happens,
the hardware issues Stop command.

The interrupt indicating timeout will not be triggered as soon as we
enable them since the Master Interrupt Status is cleared when master
mode is entered again (which happens before enabling irqs) meaning this
error is lost and the transfer is continued even though the Stop was
issued on the bus. The subsequent operations completes without error but
a bogus value (0xFF in case of read) is read as the client device is
confused because aborted transfer. No error is returned from
master_xfer() making caller believe that a valid value was read.

To fix the problem, the TSS bit (indicating timeout) in Master Interrupt
Status register is checked before each transfer. If it is set, there was
a timeout before this transfer and (as described above) the hardware
already issued Stop command so the transaction should be aborted thus
-ETIMEOUT is returned from the master_xfer() callback. In order to be
sure no timeout was issued we can't just read the status just before
starting new transaction as there will always be a small window of time
(few CPU cycles at best) where this might still happen. For this reason
we have to temporally disable the timer before checking for TSS bit.
Disabling it will, however, clear the TSS bit so in order to preserve
that information, we have to read it in ISR so we have to ensure that
the TSS interrupt is not masked between transfers of one transaction.
There is no need to call bus recovery or controller reinitialization if
that happens so it's skipped.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-06 23:14:53 +01:00
Pierre-Yves MORDRET
4e7bca6fc0 i2c: i2c-stm32f7: add PM Runtime support
Use PM Runtime API to enable/disable clock

Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-01 00:14:45 +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
39129f28c9 i2c: nvidia-gpu: limit reads also for combined messages
If the controller can only do 4 byte reads, this needs to be applied for
the read-part of combined messages, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: c71bcdcb42 ("i2c: add i2c bus driver for NVIDIA GPU")
Acked-by: Ajay Gupta <ajayg@nvidia.com>
Tested-by: Ajay Gupta <ajayg@nvidia.com>
2018-11-27 14:00:22 +01:00
Wolfram Sang
98be694ba2 i2c: nvidia-gpu: adhere to I2C fault codes
As described in Documentation/i2c/fault-codes.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: c71bcdcb42 ("i2c: add i2c bus driver for NVIDIA GPU")
Acked-by: Ajay Gupta <ajayg@nvidia.com>
Tested-by: Ajay Gupta <ajayg@nvidia.com>
2018-11-27 13:59:10 +01:00
Simon Horman
5eb316e636 i2c: sh_mobile: add support for r8a77990 (R-Car E3)
Add support for the IIC code for the r8a77990 (R-Car E3).

It is not considered compatible with existing fallback bindings
due to the documented absence of automatic transmission registers.

These registers are currently not used by the driver and
thus the provides the same behaviour for "renesas,iic-r8a77990" and
"renesas,rcar-gen3-iic". The point of declaring incompatibility is
to allow for automatic transmission register support to be added to
"renesas,iic-r8a77990" and "renesas,rcar-gen3-iic" in future.

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>
2018-11-27 13:30:01 +01:00