Re: [PATCH v7 00/34] Improvements for Tegra I2C driver

From: Thierry Reding
Date: Mon Sep 21 2020 - 06:23:47 EST


On Wed, 09 Sep 2020 01:39:32 +0300, Dmitry Osipenko wrote:
> Hello!
>
> This series performs refactoring of the Tegra I2C driver code and hardens
> the atomic-transfer mode.
>
> Changelog:
>
> v7: - Reworked the "Clean up probe function" patch by moving out all
> variable renamings into the "Clean up variable names" patch.
> This results in a nicer diff, which was asked by Andy Shevchenko.
>
> - Squashed "Improve coding style of tegra_i2c_wait_for_config_load()"
> patch into "Factor out register polling into separate function" in
> order avoid unnecessary ping-pong changes, which was asked by
> Andy Shevchenko.
>
> - Added more indentation improvements, it should be ideal now.
>
> - I haven't changed order of the "Clean up variable types" patch,
> which was suggested by Andy Shevchenko, because I already moved
> that patch multiple times and we decided to sort patches starting
> with more important cleanups and down to less important. The type
> changes are more important than shuffling code around, IMO.
>
> v6: - Added new patch that adds missing RPM puts, thanks to Andy Shevchenko
> for the suggestion.
>
> - Improved commit messages by extending them with more a more detailed
> explanation of the changes.
>
> - Added clarifying comment to the "Use reset_control_reset()" change,
> which was asked by Andy Shevchenko.
>
> - Refactored the "Clean up probe function" patch by moving the
> dev_err_probe() change into the "Use clk-bulk helpers" patch,
> which was suggested by Andy Shevchenko.
>
> - Improved ordering of the patches like it was suggested by
> Andy Shevchenko.
>
> - Added Andy Shevchenko to suggested-by of the "Use clk-bulk helpers"
> patch.
>
> - Improved "Remove i2c_dev.clk_divisor_non_hs_mode member" patch by
> making the case-switch to use "fast plus mode" timing if clock rate
> is out-of-range. Just to make it more consistent.
>
> - The "Improve tegra_i2c_dev structure" patch is squashed into
> "Improve formatting of variables" and "Clean up types/names" patches.
>
> - All variable-renaming changes are squashed into a single "Clean up
> variable names" patch.
>
> - Made extra minor improvement to various patches, like more comments
> and indentations improved.
>
> v5: - Dropped the "Factor out runtime PM and hardware initialization"
> patch, like it was suggested by Michał Mirosław. Instead a less
> invasive "Factor out hardware initialization into separate function"
> patch added, it doesn't touch the RPM initialization.
>
> - The "Remove outdated barrier()" patch now removes outdated comments.
>
> - Updated commit description of the "Remove "dma" variable" patch,
> saying that the transfer mode may be changed by a callee. This was
> suggested by Michał Mirosław.
>
> - Reworked the "Clean up and improve comments" patch. Couple more
> comments are corrected and reworded now.
>
> - Added r-b's from Michał Mirosław.
>
> - New patches:
>
> i2c: tegra: Mask interrupt in tegra_i2c_issue_bus_clear()
> i2c: tegra: Remove redundant check in tegra_i2c_issue_bus_clear()
> i2c: tegra: Don't fall back to PIO mode if DMA configuration fails
> i2c: tegra: Clean up variable types
> i2c: tegra: Improve tegra_i2c_dev structure
>
> v4: - Reordered patches in the fixes/features/cleanups order like it was
> suggested by Andy Shevchenko.
>
> - Now using clk-bulk API, which was suggested by Andy Shevchenko.
>
> - Reworked "Make tegra_i2c_flush_fifos() usable in atomic transfer"
> patch to use iopoll API, which was suggested by Andy Shevchenko.
>
> - Separated "Clean up probe function" into several smaller patches.
>
> - Squashed "Add missing newline before returns" patch into
> "Clean up whitespaces, newlines and indentation".
>
> - The "Drop '_timeout' from wait/poll function names" is renamed to
> "Rename wait/poll functions".
>
> - The "Use reset_control_reset()" is changed to not fail tegra_i2c_init(),
> but only emit warning. This should be more friendly behaviour in oppose
> to having a non-bootable machine if reset-control fails.
>
> - New patches:
>
> i2c: tegra: Remove error message used for devm_request_irq() failure
> i2c: tegra: Use devm_platform_get_and_ioremap_resource()
> i2c: tegra: Use platform_get_irq()
> i2c: tegra: Use clk-bulk helpers
> i2c: tegra: Remove bogus barrier()
> i2c: tegra: Factor out register polling into separate function
> i2c: tegra: Consolidate error handling in tegra_i2c_xfer_msg()
> i2c: tegra: Clean up and improve comments
> i2c: tegra: Rename couple "ret" variables to "err"
>
> v3: - Optimized "Make tegra_i2c_flush_fifos() usable in atomic transfer"
> patch by pre-checking FIFO state before starting to poll using
> ktime API, which may be expensive under some circumstances.
>
> - The "Clean up messages in the code" patch now makes all messages
> to use proper capitalization of abbreviations. Thanks to Andy Shevchenko
> and Michał Mirosław for the suggestion.
>
> - The "Remove unnecessary whitespaces and newlines" patch is transformed
> into "Clean up whitespaces and newlines", it now also adds missing
> newlines and spaces.
>
> - Reworked the "Clean up probe function" patch in accordance to
> suggestion from Michał Mirosław by factoring out only parts of
> the code that make error unwinding cleaner.
>
> - Added r-b from Michał Mirosław.
>
> - Added more patches:
>
> i2c: tegra: Reorder location of functions in the code
> i2c: tegra: Factor out packet header setup from tegra_i2c_xfer_msg()
> i2c: tegra: Remove "dma" variable
> i2c: tegra: Initialization div-clk rate unconditionally
> i2c: tegra: Remove i2c_dev.clk_divisor_non_hs_mode member
>
> v2: - Cleaned more messages in the "Clean up messages in the code" patch.
>
> - The error code of reset_control_reset() is checked now.
>
> - Added these new patches to clean up couple more things:
>
> i2c: tegra: Check errors for both positive and negative values
> i2c: tegra: Improve coding style of tegra_i2c_wait_for_config_load()
> i2c: tegra: Remove unnecessary whitespaces and newlines
> i2c: tegra: Rename variable in tegra_i2c_issue_bus_clear()
> i2c: tegra: Improve driver module description
>
> Dmitry Osipenko (34):
> i2c: tegra: Make tegra_i2c_flush_fifos() usable in atomic transfer
> i2c: tegra: Add missing pm_runtime_put()
> i2c: tegra: Handle potential error of tegra_i2c_flush_fifos()
> i2c: tegra: Mask interrupt in tegra_i2c_issue_bus_clear()
> i2c: tegra: Initialize div-clk rate unconditionally
> i2c: tegra: Remove i2c_dev.clk_divisor_non_hs_mode member
> i2c: tegra: Runtime PM always available on Tegra
> i2c: tegra: Remove error message used for devm_request_irq() failure
> i2c: tegra: Use reset_control_reset()
> i2c: tegra: Use devm_platform_get_and_ioremap_resource()
> i2c: tegra: Use platform_get_irq()
> i2c: tegra: Use clk-bulk helpers
> i2c: tegra: Move out all device-tree parsing into tegra_i2c_parse_dt()
> i2c: tegra: Clean up probe function
> i2c: tegra: Reorder location of functions in the code
> i2c: tegra: Clean up variable types
> i2c: tegra: Remove outdated barrier()
> i2c: tegra: Remove likely/unlikely from the code
> i2c: tegra: Remove redundant check in tegra_i2c_issue_bus_clear()
> i2c: tegra: Remove "dma" variable from tegra_i2c_xfer_msg()
> i2c: tegra: Don't fall back to PIO mode if DMA configuration fails
> i2c: tegra: Rename wait/poll functions
> i2c: tegra: Factor out error recovery from tegra_i2c_xfer_msg()
> i2c: tegra: Factor out packet header setup from tegra_i2c_xfer_msg()
> i2c: tegra: Factor out register polling into separate function
> i2c: tegra: Factor out hardware initialization into separate function
> i2c: tegra: Check errors for both positive and negative values
> i2c: tegra: Consolidate error handling in tegra_i2c_xfer_msg()
> i2c: tegra: Improve formatting of variables
> i2c: tegra: Clean up variable names
> i2c: tegra: Clean up printk messages
> i2c: tegra: Clean up and improve comments
> i2c: tegra: Clean up whitespaces, newlines and indentation
> i2c: tegra: Improve driver module description
>
> drivers/i2c/busses/i2c-tegra.c | 1435 ++++++++++++++++----------------
> 1 file changed, 701 insertions(+), 734 deletions(-)
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

Test results:
14 builds: 14 pass, 0 fail
9 boots: 9 pass, 0 fail
47 tests: 47 pass, 0 fail

Boards tested: tegra20-ventana, tegra30-cardhu-a04, tegra124-jetson-tk1,
tegra186-p2771-0000, tegra194-p2972-0000