Commit Graph

3475 Commits

Author SHA1 Message Date
Serge Semin
fac25d7aaa i2c: designware: Retrieve quirk flags as early as possible
Some platforms might need to activate the driver quirks at a very early
probe stage. For instance, Baikal-T1 System I2C doesn't need to map the
registers space as ones belong to the system controller. Instead it will
request the syscon regmap from the parental DT node. In order to be able
to do so let's retrieve the model flags right after the DW I2C private
data is created. While at it replace the or-assignment with just
assignment operator since or-ing is redundant at this stage.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 23:03:06 +02:00
Serge Semin
0daede80f8 i2c: designware: Convert driver to using regmap API
Seeing the DW I2C driver is using flags-based accessors with two
conditional clauses it would be better to replace them with the regmap
API IO methods and to initialize the regmap object with read/write
callbacks specific to the controller registers map implementation. This
will be also handy for the drivers with non-standard registers mapping
(like an embedded into the Baikal-T1 System Controller DW I2C block, which
glue-driver is a part of this series).

As before the driver tries to detect the mapping setup at probe stage and
creates a regmap object accordingly, which will be used by the rest of the
code to correctly access the controller registers. In two places it was
appropriate to convert the hand-written read-modify-write and
read-poll-loop design patterns to the corresponding regmap API
ready-to-use methods.

Note the regmap IO methods return value is checked only at the probe
stage. The rest of the code won't do this because basically we have
MMIO-based regmap so non of the read/write methods can fail (this also
won't be needed for the Baikal-T1-specific I2C controller).

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[wsa: fix type of 'rx_valid' and remove outdated kdoc var description]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 23:02:22 +02:00
Serge Semin
c615f5c65f i2c: designware: Discard Cherry Trail model flag
A PM workaround activated by the flag MODEL_CHERRYTRAIL has been removed
since commit 9cbeeca050 ("i2c: designware: Remove Cherry Trail PMIC I2C
bus pm_disabled workaround"), but the flag most likely by mistake has been
left in the Dw I2C drivers. Let's remove it. Since MODEL_MSCC_OCELOT is
the only model-flag left, redefine it to be 0x100 so setting a very first
bit in the MODEL_MASK bits range.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 11:33:54 +02:00
Serge Semin
c2549011db i2c: designware: Add Baytrail sem config DW I2C platform dependency
Currently Intel Baytrail I2C semaphore is a feature of the DW APB I2C
platform driver. It's a bit confusing to see it's config in the menu at
some separated place with no reference to the platform code. Let's move the
config definition to be below the I2C_DESIGNWARE_PLATFORM config and mark
it with "depends on I2C_DESIGNWARE_PLATFORM" statement. By doing so the
config menu will display the feature right below the DW I2C platform
driver item and will indent it to the right so signifying its belonging.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 11:33:37 +02:00
Serge Semin
68fe6cedf0 i2c: designware: slave: Set DW I2C core module dependency
DW APB I2C slave code in fact depends on the DW I2C driver core, but not
on the platform code as it used to be before commit 90bc1ee6de9f ("i2c:
designware: Allow slave mode for PCI enumerated devices"). Yes, the I2C
slave interface is currently supported by both the platform and PCI
versions of the IP core, but it still depends on the DW I2C core
functionality and must be available only if the last one is enabled.
So make sure the DW APB I2C slave config is only available if the
I2C_DESIGNWARE_CORE config is enabled.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 11:33:35 +02:00
Serge Semin
bbc5d36c5f i2c: designware: Use -y to build multi-object modules
Since commit 4f82728027 ("Documentation: update kbuild loadable modules
goals & examples") `-objs` is fitted for building host programs, lets
change DW I2C core, platform and PCI driver kbuild directives to using
`-y`, which more straightforward for device drivers. By doing so we can
discard the ifeq construction in favor to the more natural and less bulky
`<module>-$(CONFIG_X) += x.o`

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30 11:33:34 +02:00
Viresh Kumar
34765c19cc i2c: sh_mobile: simplify code and remove false compilation warning
This currently generates a warning:

drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr':
drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]

Though the code looks okay and shouldn't ever use the variable
uninitialized. Fix the warning by moving the code around and getting rid
of 'data'.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: minor updates to commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-29 14:06:35 +02:00
Jean Delvare
01590f361e i2c: i801: Instantiate SPD EEPROMs automatically
Call the function to instantiate SPD EEPROMs automatically on the
main SMBus controller.

Multiplexed SMBus systems are excluded for now as they are more
complex to handle.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-29 12:55:47 +02:00
Aishwarya Ramakrishnan
ed2ac8116f i2c: nvidia-gpu: Use PTR_ERR_OR_ZERO() to simplify code
PTR_ERR_OR_ZERO contains if(IS_ERR(...)) + PTR_ERR.

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Aishwarya Ramakrishnan <aishwaryarj100@gmail.com>
Reviewed-by: Ajay Gupta <ajayg@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-27 12:07:34 +02:00
Tang Bin
d1fdeb314e i2c: efm32: Avoid unnecessary check in efm32_i2c_probe()
The function efm32_i2c_probe() is only called with an
openfirmware platform device.Therefore there is no need
to check that it has an openfirmware node.

Signed-off-by: Shengju Zhang <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 17:08:19 +02:00
Tang Bin
79f7ab3a64 i2c: efm32: Omit superfluous error message in efm32_i2c_probe()
In the function efm32_i2c_probe(),when get irq failed,the function
platform_get_irq() logs an error message,so remove redundant message
here.

Signed-off-by: Shengju Zhang <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 17:08:13 +02:00
Andy Shevchenko
3f35064a7c i2c: designware: Drop hard coded FIFO depth assignment
It's not clear why the commit fe20ff5c7e
  ("i2c-designware: Add support for Designware core behind PCI devices.")
followed by commit b61b14154b
  ("i2c-designware: add support for Intel Lynxpoint")
chose to hard code FIFO depth size. The FIFO depth on all hardware,
I have tested on, can be nicely detected automatically.

Thus, we may safely drop hard coded FIFO sizes from the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:43 +02:00
Andy Shevchenko
64d0a0755c i2c: designware: Read counters from ACPI for PCI driver
PCI devices may have been backed with ACPI handle which supplies
an additional information to the drivers, such as counters.

Call for ACPI configuration from PCI driver in order to utilize counters
provided by ACPI.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:39 +02:00
Andy Shevchenko
f9288fcc5c i2c: designware: Move ACPI parts into common module
For possible code reuse in the future, move ACPI parts into common module.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:37 +02:00
Andy Shevchenko
462cfcb4aa i2c: designware: Drop unneeded condition in i2c_dw_validate_speed()
We may bailout directly from the loop instead of breaking it and
testing a loop counter. This also gives advantages such as decreased
indentation level along with dropped unneeded condition.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:30 +02:00
Andy Shevchenko
20ee1d9020 i2c: designware: Move i2c_dw_validate_speed() helper to a common code
In order to export array supported speed for wider use, move it
to a header along with i2c_dw_validate_speed() helper moved to
a common code.

No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:27 +02:00
Andy Shevchenko
a19f133f69 i2c: designware: Include proper headers in i2c-desingware-core.h
This header is a user of some generic ones, include them respectively.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:19 +02:00
Andy Shevchenko
ab0ef8bac1 i2c: designware: Get rid of PCI driver specifics in common code
Do not spread PCI specifics over common code. It seems to be a layering
violation which can be easily avoided. Refactor PCI driver and drop
PCI specifics from common code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22 16:50:17 +02:00
Russell King
7c9ec2c525 i2c: pxa: implement generic i2c bus recovery
Implement generic GPIO-based I2C bus recovery for the PXA I2C driver.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-20 17:57:23 +02:00
Wolfram Sang
4f118a7e46 i2c: tegra: Changes for v5.8-rc1
This includes a few improvements to make the Tegra I2C controller behave
 properly on suspend/resume, does a bit of cleanup and adds support for
 the VI-variant of the I2C controller that is used primarily for video
 capture purposes.
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Merge tag 'for-5.8-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into i2c/for-5.8

i2c: tegra: Changes for v5.8-rc1

This includes a few improvements to make the Tegra I2C controller behave
properly on suspend/resume, does a bit of cleanup and adds support for
the VI-variant of the I2C controller that is used primarily for video
capture purposes.
2020-05-20 15:37:21 +02:00
Atsushi Nemoto
ab1c6093f6 i2c: altera: cleanup spinlock
Protect altr_i2c_int_enable() by the mutex and remove unneeded spinlock.

Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-20 15:28:03 +02:00
Wolfram Sang
f89c326dca Merge branch 'i2c/for-current-fixed' into i2c/for-5.8 2020-05-20 15:27:45 +02:00
Qii Wang
be5ce0e97c i2c: mediatek: Add i2c ac-timing adjust support
This patch adds a algorithm to calculate some ac-timing parameters
which can fully meet I2C Spec.

Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-20 15:25:55 +02:00
Atsushi Nemoto
5d4c797749 i2c: altera: Fix race between xfer_msg and isr thread
Use a mutex to protect access to idev->msg_len, idev->buf, etc. which
are modified by both altr_i2c_xfer_msg() and altr_i2c_isr().

This is the minimal fix for easy backporting. A cleanup to remove the
spinlock will be added later.

Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Acked-by: Thor Thayer <thor.thayer@linux.intel.com>
[wsa: updated commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-15 11:23:49 +02:00
Codrin Ciubotariu
7d66976fe7 i2c: at91: Fix pinmux after devm_gpiod_get() for bus recovery
devm_gpiod_get() usually calls gpio_request_enable() for non-strict pinmux
drivers. These puts the pins in GPIO mode, whithout notifying the pinctrl
driver. At this point, the I2C bus no longer owns the pins. To mux the
pins back to the I2C bus, we use the pinctrl driver to change the state
of the pins to GPIO, before using devm_gpiod_get(). After the pins are
received as GPIOs, we switch theer pinctrl state back to the default
one,

Fixes: d3d3fdcc4c ("i2c: at91: implement i2c bus recovery")
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-15 11:23:33 +02:00
Andy Shevchenko
7943f1d178 i2c: designware: Allow slave mode for PCI enumerated devices
Allow slave mode for PCI enumerated devices by calling a common i2c_dw_probe()
instead of i2c_dw_probe_master().

While dropping dependency to platform driver in slave module, move its
configuration section above, closer to core.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13 12:36:22 +02:00
Andy Shevchenko
bed20c8402 i2c: designware: Rename i2c_dw_probe() to i2c_dw_probe_master()
As a preparatory patch to support slave mode for PCI enumerated devices rename
i2c_dw_probe() to i2c_dw_probe_master() and split common i2c_dw_probe() as
inline helper.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13 12:36:22 +02:00
Andy Shevchenko
42ab001234 i2c: designware: Switch PCI driver to use i2c_dw_configure_master()
Since we have available helper to configure master mode, let's use it
in the PCI driver instead of spread open-coded variant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13 12:36:22 +02:00
Andy Shevchenko
3ebe40ed1c i2c: designware: Move configuration routines to respective modules
Move configuration routines to respective modules, i.e. master and slave.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13 12:36:22 +02:00
Andy Shevchenko
188fe480cd i2c: designware: Use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() instead of
platform_get_resource() + devm_ioremap_resource().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13 12:36:22 +02:00
Thierry Reding
c73178b937 i2c: tegra: Add support for the VI I2C on Tegra210
Tegra210 has an extra instance of the I2C controller that is in the
domain of host1x and usually used for camera use-cases. The programming
model for the VI variant of the controller is roughly the same as for
the other variants, except that the I2C registers start at an offset
and are spaced further apart. VI I2C also doesn't support slave mode.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-12 22:47:52 +02:00
Thierry Reding
82dd45f5cb i2c: tegra: Use FIELD_PREP/FIELD_GET macros
Using these macros helps increase readability of the code.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-12 22:47:52 +02:00
Russell King
2fd6cbf41a i2c: pxa: use master-abort for device probes
Use master-abort to send the stop condition after an address cycle
rather than resetting the controller.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:37:30 +02:00
Russell King
e81c979f4e i2c: pxa: clear all master action bits in i2c_pxa_stop_message()
If we timeout during a message transfer, the control register may
contain bits that cause an action to be set. Read-modify-writing the
register leaving these bits set may trigger the hardware to attempt
one of these actions unintentionally.

Always clear these bits when cleaning up after a message or after
a timeout.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:37:15 +02:00
Russell King
18d30c0946 i2c: pxa: remove some unnecessary debug
Remove unnecessary show_state() in the loop inside
i2c_pxa_pio_set_master(), which can be unnecessarily verbose.

Remove the i2c_pxa_scream_blue_murder() in i2c_pxa_pio_xfer(), which
will trigger if we are probing the I2C bus and a slave does not
respond; this is a normal event, and not something to report.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:32:52 +02:00
Russell King
ae1c3b7394 i2c: pxa: ensure timeout messages are unique
Ensure that the various timeout messages can identify where in the code
they were produced from to aid debugging.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:32:44 +02:00
Russell King
c25e509aef i2c: pxa: avoid complaints with non-responsive slaves
Running i2cdetect on a PXA I2C adapter is very noisy; it complains
whenever a slave fails to respond to the address cycle.  Since it is
normal to probe for slaves in this way, we should not fill the kernel
log.  This is especially true with SFP modules that take a while to
respond on the I2C bus, and probing via the I2C bus is the only way to
detect that they are ready.

Fix this by changing the internal transfer return code from I2C_RETRY
to a new NO_SLAVE code (mapped to -ENXIO, as per the I2C documentation
for this condition, but we still return -EREMOTEIO to the I2C stack to
maintain long established driver behaviour.)

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:32:31 +02:00
Russell King
0f03c08892 i2c: pxa: consolidate i2c_pxa_*xfer() implementations
Most of i2c_pxa_pio_xfer() and i2c_pxa_xfer() are identical; the only
differences are that i2c_pxa_pio_xfer() may reset the bus, and they
use different underlying transfer functions. The retry loop is the
same. Consolidate these two functions.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12 12:32:20 +02:00
Dmitry Osipenko
a70ff65601 i2c: tegra: Synchronize DMA before termination
DMA transfer could be completed, but CPU (which handles DMA interrupt)
may get too busy and can't handle the interrupt in a timely manner,
despite of DMA IRQ being raised. In this case the DMA state needs to
synchronized before terminating DMA transfer in order not to miss the
DMA transfer completion.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-08 12:42:33 +02:00
Dmitry Osipenko
566c05f7cd i2c: tegra: Better handle case where CPU0 is busy for a long time
Boot CPU0 always handle I2C interrupt and under some rare circumstances
(like running KASAN + NFS root) it may stuck in uninterruptible state for
a significant time. In this case we will get timeout if I2C transfer is
running on a sibling CPU, despite of IRQ being raised. In order to handle
this rare condition, the IRQ status needs to be checked after completion
timeout.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-08 12:42:33 +02:00
Thierry Reding
26ca88aaea i2c: tegra: Keep IRQs enabled during suspend/resume
One of the I2C controllers on Tegra SoCs is typically connected to a
system PMIC, which provides controls for critical power supplies for
most platforms.

Some drivers, such as PCI, need to disable these regulators during a
very late stage during suspend and resume them at a very early stage
during resume.

To support these use-cases, keep interrupts disabled during suspend/
resume.

Suggested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-08 12:42:32 +02:00
Thierry Reding
44c99904cf i2c: tegra: Restore pinmux on system resume
Depending on the board design, the I2C controllers found on Tegra SoCs
may require pinmuxing in order to function. This is done as part of the
driver's runtime suspend/resume operations. However, the PM core does
not allow devices to go into runtime suspend during system sleep to
avoid potential races with the suspend/resume of their parents.

As a result of this, when Tegra SoCs resume from system suspend, their
I2C controllers may have lost the pinmux state in hardware, whereas the
pinctrl subsystem is not aware of this. To fix this, make sure that if
the I2C controller is not runtime suspended, the runtime suspend code is
still executed in order to disable the module clock (which we don't need
to be enabled during sleep) and set the pinmux to the idle state.

Conversely, make sure that the I2C controller is properly resumed when
waking up from sleep so that pinmux settings are properly restored.

This fixes a bug seen with DDC transactions to an HDMI monitor timing
out when resuming from system suspend.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-08 12:42:11 +02:00
Thierry Reding
78ad734218 Revert "i2c: tegra: Fix suspending in active runtime PM state"
This reverts commit 9f42de8d4e.

It's not safe to use pm_runtime_force_{suspend,resume}(), especially
during the noirq phase of suspend. See also the guidance provided in
commit 1e2ef05bb8 ("PM: Limit race conditions between runtime PM
and system sleep (v2)").

Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-07 11:45:45 +02:00
Codrin Ciubotariu
73371d5f31 i2c: at91: Send bus clear command if SDA is down
After a transfer timeout, some faulty I2C slave devices might hold down
the SDA pin. We can generate a bus clear command, hoping that the slave
might release the pins.
If the CLEAR command is not supported, we will use gpio recovery, if
available, to reset the bus.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 16:37:21 +02:00
Russell King
e896be5ad1 i2c: pxa: fix i2c_pxa_wait_bus_not_busy() boundary condition
Fix i2c_pxa_wait_bus_not_busy()'s boundary conditions, so that a
coincidental success and timeout results in the function returning
success.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:51:07 +02:00
Russell King
bb82ba6907 i2c: pxa: clean up decode_bits()
Clean up decode_bits() to use pr_cont(), and move the newline into the
function rather than at its two callsites. Avoid printing an
unnecessary space before the newline.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:51:01 +02:00
Russell King
88b73ee7ca i2c: pxa: fix i2c_pxa_scream_blue_murder() debug output
The IRQ log output is supposed to appear on a single line.  However,
commit 3a2dc1677b ("i2c: pxa: Update debug function to dump more info
on error") resulted in it being printed one-entry-per-line, which is
excessively long.

Fixing this is not a trivial matter; using pr_cont() doesn't work as
the previous dev_dbg() may not have been compiled in, or may be
dynamic.

Since the rest of this function output is at error level, and is also
debug output, promote this to error level as well to avoid this
problem.

Reduce the number of always zero prefix digits to save screen real-
estate.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:50:55 +02:00
Russell King
70aee287cf i2c: pxa: move DT IDs along side platform IDs
Move the ID tables into one place, near the device dependent data.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:50:48 +02:00
Russell King
79622f372b i2c: pxa: move private definitions to i2c-pxa.c
Move driver-private definitions out of the i2c-pxa.h platform data
header file into the driver itself. Nothing outside of the driver
makes use of these constants.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:50:41 +02:00
Russell King
ee478936dd i2c: pxa: always set fm and hs members for each type
Always set the fm and hs members of struct pxa_reg_layout. These
members are already taking space, we don't need code as well.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-05 14:50:33 +02:00