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>
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>
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>
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>
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
...
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>
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>
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>
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>
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>
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>
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
...
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>
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>
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>
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>
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>
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
...
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>
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>
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
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>
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>
Update the comments to match current behaviour. Shorten some comments.
Update copyrights.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If we don't clear START generation as soon as possible, it may cause
another message to be generated, e.g. when receiving NACK in address
phase. To keep the race window as small as possible, we clear it right
at the beginning of the interrupt. We don't need any checks since we
always want to stop START and STOP generation on the next occasion after
we started it.
This patch improves the situation but sadly does not completely fix it.
It is still to be researched if we can do better given this HW design.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Due to the HW design, master IRQs are timing critical, so give them
precedence over slave IRQ.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The manual says (55.4.8.6) that HW does automatically send STOP after
NACK was received. My measuerments confirm that.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Setting up new messages was done in process context while handling a
message was in interrupt context. Because of the HW design, this IP core
is sensitive to timing, so the context switches were too expensive. Move
this setup to interrupt context as well.
In my test setup, this fixed the occasional 'data byte sent twice' issue
which a number of people have seen. It also fixes to send REP_START
after a read message which was wrongly send as a STOP + START sequence
before.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
After making sure to reinit the HW and clear interrupts in the timeout
case, we know that interrupts are always disabled in the sections
protected by the spinlock. Thus, we can simply remove it which is a
preparation for further refactoring. While here, rename the timeout
variable to time_left which is way more readable.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We don't need to init HW before every transfer since we know the HW
state then. HW init at probe time is enough. While here, add setting the
clock register which belongs to init HW. Also, set MDBS bit since not
setting it is prohibited according to the manual.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When calculating the bus speed, the clock should be on, of course. Most
bootloaders left them on, so this went unnoticed so far.
Move the ioremapping out of this clock-enabled-block and prepare for
adding hw initialization there, too.
Reported-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
- New drivers: UniPhier (with and without FIFO)
- some drivers got some bigger rework: ismt, designware, img-scb (rcar
had to be reverted because issues were showing up just lately)
- ACPI: reworked the device scanning and added support for muxes
... and quite a lot of driver bugfixes and cleanups this time. All
files touched outside of the i2c realm have proper acks.
* 'i2c/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
i2c: rcar: Revert the latest refactoring series
i2c: pnx: remove superfluous assignment
MAINTAINERS: i2c: drop i2c-pnx maintainer
MAINTAINERS: i2c: mark also subdirectories as maintained
i2c: cadence: enable driver for ARM64
i2c: i801: Document Intel DNV and Broxton
i2c: at91: manage unexpected RXRDY flag when starting a transfer
i2c: pnx: Use setup_timer instead of open coding it
i2c: add ACPI support for I2C mux ports
acpi: add acpi_preset_companion() stub
i2c: pxa: Add support for pxa910/988 & new configuration features
i2c: au1550: Convert to devm_kzalloc and devm_ioremap_resource
i2c-dev: Fix I2C_SLAVE ioctl comment
i2c-dev: Fix typo in ioctl name reference
i2c: sirf: tune the divider to make i2c bus freq more accurate
i2c: imx: Use -ENXIO as error in the NACK case
i2c: i801: Add support for Intel Broxton
i2c: i801: Add support for Intel DNV
i2c: mediatek: add i2c resume support
i2c: imx: implement bus recovery
...
This whole series caused sometimes timeouts and even OOPSes on some
r8a7791 Koelsch boards. We need to understand and fix those first.
Revert "i2c: rcar: clean up after refactoring"
Revert "i2c: rcar: revoke START request early"
Revert "i2c: rcar: check master irqs before slave irqs"
Revert "i2c: rcar: don't issue stop when HW does it automatically"
Revert "i2c: rcar: init new messages in irq"
Revert "i2c: rcar: refactor setup of a msg"
Revert "i2c: rcar: remove spinlock"
Revert "i2c: rcar: remove unused IOERROR state"
Revert "i2c: rcar: rework hw init"
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since commit 4baadb9e05 ("ARM: shmobile: r8a7778: remove obsolete
setup code"), Renesas R-Car SoCs are only supported in generic DT-only
ARM multi-platform builds. The driver doesn't need to use platform data
anymore, hence remove platform data configuration.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[wsa: removed now unused ret value and cast to proper enum type]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Enable the I2C core for this SoC. I add a new type because this version
has new features (e.g. DMA) which will be added somewhen later.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The core may register clients attached to this master which may use
funtionality from the master. So, RuntimePM must be enabled before, otherwise
this will fail. While here, move drvdata, too.
Reported-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>
Cc: stable@kernel.org
Update the comments to match current behaviour. Shorten some comments.
Update copyrights.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If we don't clear START generation as soon as possible, it may cause
another message to be generated. To keep the race window as small as
possible, we clear it right at the beginning of the interrupt. We don't
need checking since we always want to stop START and STOP generation on
the next occasion after we started it.
This patch improves the situation but sadly does not completely fix it.
It is still to be researched if we can do better given this HW design.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Due to broken HW design, master IRQs are more timing critical, so give
them precedence over slave IRQ.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The manual says (55.4.8.6) that HW does automatically send STOP after
NACK was received. My measuerments confirm that.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Setting up new messages was done in process context while handling a
message was in interrupt context. Because of the HW design, this IP core
is sensitive to timing, so the context switches were too expensive. Move
this setup to interrupt context as well.
In my test setup, this fixed the occasional 'data byte sent twice' issue
which a number of people have seen. It also fixes to send REP_START
after a read message which was wrongly send as a STOP + START sequence
before.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We make sure to reinit the HW in the timeout case; then we know that
interrupts are always disabled in the sections protected by the
spinlock. Thus, we can simply remove it which is a preparation for
further refactoring. While here, rename the timeout variable to
time_left which is way more readable.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Hiromitsu Yamasaki