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path: root/drivers/i2c/busses/i2c-tegra.c
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2020-10-05i2c: tegra: Improve driver module descriptionDmitry Osipenko
Use proper spelling of "NVIDIA" and don't designate driver as Tegra2-only since newer SoC generations are supported as well. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up whitespaces, newlines and indentationDmitry Osipenko
Some places in the code are missing newlines or have unnecessary whitespaces and newlines. This creates inconsistency of the code and hurts readability. This patch removes the unnecessary and adds necessary whitespaces / newlines, clears indentation of the code. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up and improve commentsDmitry Osipenko
Make all comments to be consistent in regards to capitalization and punctuation, correct spelling and grammar errors, improve wording. Reviewed-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up printk messagesDmitry Osipenko
This patch unifies style of all messages in the driver by starting them with a lowercase letter and using consistent capitalization and wording for all messages. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up variable namesDmitry Osipenko
Rename "ret" variables to "err" in order to make code a bit more expressive, emphasizing that the returned value is an error code. Same vice versa, where appropriate. Rename variable "reg" to "val" in order to better reflect the actual usage of the variable in the code and to make naming consistent with the rest of the code. Use briefer names for a few members of the tegra_i2c_dev structure in order to improve readability of the code. All dev/&pdev->dev are replaced with i2c_dev->dev in order to have uniform code style across the driver. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Improve formatting of variablesDmitry Osipenko
Reorder definition of variables in the code to have them sorted by length and grouped logically, also replace "unsigned long" with "u32". Do this in order to make code easier to read. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Check errors for both positive and negative valuesDmitry Osipenko
The driver's code is inconsistent in regards to the error values checking. The correct way should be to check both positive and negative values. This patch cleans up the error-checks in the code. Note that the pm_runtime_get_sync() could return positive value on success, hence only relevant parts of the code are changed by this patch. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Factor out hardware initialization into separate functionDmitry Osipenko
Factor out hardware initialization into a separate function from the probe function. The only place where runtime PM needs to be resumed during probe is the place of hardware initialization, hence it makes sense to factor out it in order to have a bit cleaner error handling in tegra_i2c_probe(). Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Factor out register polling into separate functionDmitry Osipenko
Factor out register polling into a separate function in order to remove boilerplate code and make code cleaner. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Factor out packet header setup from tegra_i2c_xfer_msg()Dmitry Osipenko
The code related to packet header setting up is a bit messy and makes tegra_i2c_xfer_msg() more difficult to read than it could be. Let's factor the packet header setup from tegra_i2c_xfer_msg() into separate function in order to make code easier to read and follow. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Factor out error recovery from tegra_i2c_xfer_msg()Dmitry Osipenko
Factor out error recovery code from tegra_i2c_xfer_msg() in order to make this function easier to read and follow. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Rename wait/poll functionsDmitry Osipenko
Drop '_timeout' postfix from the wait/poll completion function names in order to make the names shorter, making code cleaner a tad. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove "dma" variable from tegra_i2c_xfer_msg()Dmitry Osipenko
The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in regards to readability and generation of the code. Besides readability, it's also not very nice that the is_curr_dma_xfer is initialized in tegra_i2c_xfer_msg() and then could be overridden by tegra_i2c_config_fifo_trig(). In a result, the "dma" variable creates slight confusion since it's not instantly obvious why it's set after tegra_i2c_config_fifo_trig(). Hence should be better to have the variable removed. This makes code more consistent. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove redundant check in tegra_i2c_issue_bus_clear()Dmitry Osipenko
The tegra_i2c_wait_for_config_load() checks for 'has_config_load_reg' by itself, hence there is no need to duplicate the check. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove likely/unlikely from the codeDmitry Osipenko
The likely/unlikely annotations should be used only in a hot paths of performance-critical code. The I2C driver doesn't have such paths, and thus, there is no justification for usage of likely/unlikely annotations in the code. Hence remove them. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove outdated barrier()Dmitry Osipenko
The barrier() was intended to reduce possibility of racing with the interrupt handler, but driver's code evolved significantly and today's driver enables interrupt only when it waits for completion notification. Hence barrier() has no good use anymore, let's remove it. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up variable typesDmitry Osipenko
Don't use signed types for unsigned values and use consistent types for sibling variables. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Reorder location of functions in the codeDmitry Osipenko
Reorder location of functions in the code in order to have definition of functions closer to the place of the invocation. This change makes easier to navigate around the code and removes the need to have a prototype for tegra_i2c_init(). Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Clean up probe functionDmitry Osipenko
The driver's probe function code is a bit difficult to read. This patch reorders code of the probe function, forming groups of code that are easy to work with. The probe tear-down order now matches the driver-removal order. Reviewed-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Move out all device-tree parsing into tegra_i2c_parse_dt()Dmitry Osipenko
Move out code related to device-tree parsing from the probe function into tegra_i2c_parse_dt() in order to make code more consistent. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Use clk-bulk helpersDmitry Osipenko
Use clk-bulk helpers and factor out clocks initialization into separate function in order to make code cleaner. The clocks initialization now performed after reset-control initialization in order to avoid a noisy -PROBE_DEFER errors on T186+ from the clk-bulk helper which doesn't silence this error code. Hence reset_control_get() now may return -EPROBE_DEFER on newer Tegra SoCs because they use BPMP driver that provides reset controls and BPMP doesn't come up early during boot. Previously rst was protected by the clocks retrieval and now this patch makes dev_err_probe() to be used for the rst error handling. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Use platform_get_irq()Dmitry Osipenko
Use common helper for retrieval of the interrupt number in order to make code cleaner. Note that platform_get_irq() prints error message by itself. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Use devm_platform_get_and_ioremap_resource()Dmitry Osipenko
Driver now uses devm_platform_get_and_ioremap_resource() which replaces the typical boilerplate code and makes code cleaner. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Use reset_control_reset()Dmitry Osipenko
Use a single reset_control_reset() instead of assert/deasset couple in order to make code cleaner a tad. Note that the reset_control_reset() uses 1 microsecond delay instead of 2 that was used previously, but this shouldn't matter because one microsecond is a default reset time for most of Tegra peripherals and TRM doesn't mention anything special in regards to I2C controller's reset propagation time. In addition don't ignore potential error of the reset control by emitting a noisy warning if it fails, which will indicate an existence of a severe problem, while still allow machine to boot up. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove error message used for devm_request_irq() failureDmitry Osipenko
The error message prints number of vIRQ, which isn't a useful information. In practice devm_request_irq() never fails, hence let's remove the bogus message in order to make code cleaner. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Runtime PM always available on TegraDmitry Osipenko
The runtime PM is guaranteed to be always available on Tegra after commit 40b2bb1b132a ("ARM: tegra: enforce PM requirement"). Hence let's remove all the RPM-availability checking and handling from the code. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Remove i2c_dev.clk_divisor_non_hs_mode memberDmitry Osipenko
The "non_hs_mode" divisor value is fixed, thus there is no need to have the variable i2c_dev.clk_divisor_non_hs_mode struct member. Let's remove it and move the mode selection into tegra_i2c_init() where it can be united with the timing selection. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Initialize div-clk rate unconditionallyDmitry Osipenko
It doesn't make sense to conditionalize the div-clk rate changes because rate is fixed and it won't ever change once it's set at the driver's probe time. All further changes are NO-OPs because CCF caches rate and skips rate-change if rate is unchanged. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Mask interrupt in tegra_i2c_issue_bus_clear()Dmitry Osipenko
The tegra_i2c_issue_bus_clear() may fail and in this case BUS_CLR_DONE stays unmasked. Hence let's mask it for consistency. This patch doesn't fix any known problems. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Handle potential error of tegra_i2c_flush_fifos()Dmitry Osipenko
Technically the tegra_i2c_flush_fifos() may fail and transfer should be aborted in this case, but this shouldn't ever happen in practice unless there is a bug somewhere in the driver. Let's add the error check just for completeness. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Add missing pm_runtime_put()Dmitry Osipenko
The pm_runtime_get_sync() always bumps refcount regardless of whether it succeeds or fails. Hence driver is responsible for restoring of the RPM refcounting. This patch adds missing RPM puts which restore refcounting in a case of pm_runtime_get_sync() error. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-10-05i2c: tegra: Make tegra_i2c_flush_fifos() usable in atomic transferDmitry Osipenko
The tegra_i2c_flush_fifos() shouldn't sleep in atomic transfer and jiffies are not updating if interrupts are disabled. Let's switch to use iopoll API helpers for register-polling. The iopoll API provides helpers for both atomic and non-atomic cases. Note that this patch doesn't fix any known problem because normally FIFO is flushed at the time of starting a new transfer. Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-28i2c: tegra: Avoid tegra_i2c_init_dma() for Tegra210 vi i2cSowjanya Komatineni
VI I2C is on host1x bus so APB DMA can't be used for Tegra210 VI I2C and there are no tx and rx dma channels for VI I2C. So, avoid attempt of requesting DMA channels. Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-28i2c: tegra: Fix runtime resume to re-init VI I2CSowjanya Komatineni
VI I2C is on host1x bus and is part of VE power domain. During suspend/resume VE power domain goes through power off/on. So, controller reset followed by i2c re-initialization is required after the domain power up. This patch fixes it. Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-28i2c: tegra: Fix the error path in tegra_i2c_runtime_resumeSowjanya Komatineni
tegra_i2c_runtime_resume does not disable prior enabled clocks properly. This patch fixes it. Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-28i2c: tegra: Remove NULL pointer check before ↵Sowjanya Komatineni
clk_enable/disable/prepare/unprepare clk_enable, clk_disable, clk_prepare, and clk_unprepare APIs have implementation for checking clk pointer not NULL and clock consumers can safely call these APIs without NULL pointer check. So, this patch cleans up Tegra i2c driver to remove explicit checks before these APIs. Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-28i2c: tegra: Don't mark VI I2C as IRQ safe runtime PMSowjanya Komatineni
Tegra VI I2C is part of VE power domain and typically used for camera usecases. VE power domain is not always on and is non-IRQ safe. So, IRQ safe device cannot be attached to a non-IRQ safe domain as it prevents powering off the PM domain and generic power domain driver will warn. Current driver marks all I2C devices as IRQ safe and VI I2C device does not require IRQ safe as it will not be used for atomic transfers. This patch has fix to make VI I2C as non-IRQ safe. Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-12i2c: tegra: Add support for the VI I2C on Tegra210Thierry Reding
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>
2020-05-12i2c: tegra: Use FIELD_PREP/FIELD_GET macrosThierry Reding
Using these macros helps increase readability of the code. Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-08i2c: tegra: Synchronize DMA before terminationDmitry Osipenko
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>
2020-05-08i2c: tegra: Better handle case where CPU0 is busy for a long timeDmitry Osipenko
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>
2020-05-08i2c: tegra: Keep IRQs enabled during suspend/resumeThierry Reding
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>
2020-05-08i2c: tegra: Restore pinmux on system resumeThierry Reding
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>
2020-05-07Revert "i2c: tegra: Fix suspending in active runtime PM state"Thierry Reding
This reverts commit 9f42de8d4ec2304f10bbc51dc0484f3503d61196. 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 1e2ef05bb8cf ("PM: Limit race conditions between runtime PM and system sleep (v2)"). Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-04-28Revert "i2c: tegra: Better handle case where CPU0 is busy for a long time"Wolfram Sang
This reverts commit a900aeac253729411cf33c6cb598c152e9e4137f because regressions were showing up. Suggested-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/dmaengine/20200319201140.17451-1-digetx@gmail.com/ Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-28Revert "i2c: tegra: Synchronize DMA before termination"Wolfram Sang
This reverts commit 8814044fe0fa182abc9ff818d3da562de98bc9a7 because regressions were showing up. Suggested-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/dmaengine/20200319201140.17451-1-digetx@gmail.com/ Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-15i2c: tegra: Synchronize DMA before terminationDmitry Osipenko
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: Wolfram Sang <wsa@the-dreams.de>
2020-04-15i2c: tegra: Better handle case where CPU0 is busy for a long timeDmitry Osipenko
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: Wolfram Sang <wsa@the-dreams.de>
2020-03-24i2c: drivers: Use generic definitions for bus frequenciesAndy Shevchenko
Since we have generic definitions for bus frequencies, let's use them. Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Acked-by: Robert Richter <rrichter@marvell.com> Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com> Acked-by: Elie Morisse <syniurge@gmail.com> Acked-by: Nehal Shah <nehal-bakulchandra.shah@amd.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Oleksij Rempel <o.rempel@pengutronix.de> Acked-by: Vladimir Zapolskiy <vz@mleia.com> Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Reviewed-by: Chris Brandt <chris.brandt@renesas.com> Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Acked-by: Patrice Chotard <patrice.chotard@st.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15i2c: tegra: Check DMA completion status in addition to left timeDmitry Osipenko
It is more robust to check completion status in addition to the left time in a case of DMA transfer because transfer's completion happens in two phases [one is ISR, other is tasklet] and thus it is possible that DMA is completed while I2C completion awaiting times out because of the deferred notification done by the DMA driver. The DMA completion status becomes 100% actual after DMA synchronization. This fixes spurious DMA timeouts when system is under load. Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>