30 Commits

Author SHA1 Message Date
Paul Cercueil
775a3c4741 i2c: img-scb: Remove #ifdef guards for PM related functions
Use the new PM macros for the suspend and resume functions to be
automatically dropped by the compiler when CONFIG_PM or
CONFIG_PM_SLEEP are disabled, without having to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230722115046.27323-10-paul@crapouillou.net
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2023-08-08 15:36:49 +02:00
Linus Torvalds
5def00ca25 Biggest news is not a patch this time
* I2C has now a co-maintainer taking care of the host drivers. Welcome
   Andi Shyti and have fun!
 * platform remove callback converted to return void in drivers
 * simplify drivers by using devm_clk_get_enabled()
 * introduce i2c_get_match_data() to avoid more boilerplate code
   (especially since the core stopped delivering an i2c_device_id)
 * and the usual bunch of driver updates
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Merge tag 'i2c-for-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

 - I2C has now a co-maintainer taking care of the host drivers. Welcome
   Andi Shyti and have fun!

 - platform remove callback converted to return void in drivers

 - simplify drivers by using devm_clk_get_enabled()

 - introduce i2c_get_match_data() to avoid more boilerplate code
   (especially since the core stopped delivering an i2c_device_id)

 - and the usual bunch of driver updates

* tag 'i2c-for-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits)
  i2c: uniphier: Use devm_clk_get_enabled()
  i2c: uniphier-f: Use devm_clk_get_enabled()
  i2c: owl: Use devm_clk_get_enabled()
  i2c: lpc2k: Use devm_clk_get_enabled()
  i2c: hix5hd2: Use devm_clk_get_enabled()
  i2c: sun6i-p2wi: Use devm_clk_get_enabled()
  i2c: pasemi-platform: Use devm_clk_get_enabled()
  i2c: mt7621: Use devm_clk_get_enabled()
  i2c: xiic: Use devm_clk_get_enabled()
  i2c: davinci: Use platform table macro over module_alias
  i2c: ocores: use devm_ managed clks
  i2c: nomadik: Use dev_err_probe() whenever possible
  i2c: nomadik: Use devm_clk_get_enabled()
  i2c: nomadik: Remove unnecessary goto label
  usb: typec: ucsi: Mark dGPUs as DEVICE scope
  i2c: wmt: Use devm_platform_get_and_ioremap_resource()
  i2c: versatile: Use devm_platform_get_and_ioremap_resource()
  i2c: hix5hd2: Add I2C_M_STOP flag support for i2c-hix5hd2 driver.
  i2c: mpc: Use of_property_read_reg() to parse "reg"
  i2c: imx-lpi2c: Don't open-code DIV_ROUND_UP
  ...
2023-07-02 10:22:38 -07:00
XU pengfei
edaac7d9ff i2c: img-scb: remove unnecessary (void*) conversion
Signed-off-by: XU pengfei <xupengfei@nfschina.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-06-08 22:19:06 +02:00
Christian Heusel
8110bf24c8 i2c: img-scb: Fix spelling mistake "innacurate" -> "inaccurate"
There is a spelling mistake in a comment. Fix it.

Signed-off-by: Christian Heusel <christian@heusel.eu>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-06-05 10:39:11 +02:00
Uwe Kleine-König
e190a0c389 i2c: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Rosin <peda@axentia.se>
Acked-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Asmaa Mnebhi <asnaa@nvidia.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Chris Pringle <chris.pringle@phabrix.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Tali Perry <tali.perry@nuvoton.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-06-05 09:47:37 +02:00
Qinglang Miao
223125e37a i2c: img-scb: fix reference leak when pm_runtime_get_sync fails
The PM reference count is not expected to be incremented on
return in functions img_i2c_xfer and img_i2c_init.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

Fixes: 93222bd9b966 ("i2c: img-scb: Add runtime PM")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-04-14 09:49:06 +02:00
Dejin Zheng
e42688ed5c i2c: busses: remove duplicate dev_err()
it will print an error message by itself when platform_get_irq()
goes wrong. so don't need dev_err() in here again.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-18 23:42:14 +02:00
Dejin Zheng
e0442d7621 i2c: busses: convert to devm_platform_ioremap_resource
use devm_platform_ioremap_resource() to simplify code, it
contains platform_get_resource and devm_ioremap_resource.

Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Robert Richter <rrichter@marvell.com>
Acked-by: Thor Thayer <thor.thayer@linux.intel.com>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-15 12:09:09 +02:00
Andy Shevchenko
90224e6468 i2c: drivers: Use generic definitions for bus frequencies
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>
2020-03-24 22:36:59 +01:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Ed Blake
93222bd9b9 i2c: img-scb: Add runtime PM
The i2c-img-scb driver already dynamically enables / disables clocks to
save power, but doesn't use the runtime PM framework. Convert the
driver to use runtime PM, so that dynamic clock management will be
disabled when runtime PM is disabled, and so that autosuspend can be
used to avoid unnecessarily disabling and re-enabling clocks repeatedly
during a sequence of transactions.

Signed-off-by: Ed Blake <ed.blake@sondrel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-28 14:03:45 +02:00
Kees Cook
b9e43e363d i2c/busses: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-27 15:53:30 +02:00
James Hogan
e0a8631287 Update James Hogan's email address
Update my imgtec.com and personal email address to my kernel.org one in
a few places as MIPS will soon no longer be part of Imagination
Technologies, and add mappings in .mailcap so get_maintainer.pl reports
the right address.

Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-04 17:11:53 -07:00
Geliang Tang
879bce2285 i2c: img-scb: use setup_timer
Use setup_timer() instead of init_timer() to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-16 21:51:30 +02:00
Wolfram Sang
ea734404f3 i2c: don't print error when adding adapter fails
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>
2016-08-22 08:19:55 +02:00
Wolfram Sang
9c01cae8dd i2c: img-scb: use new 8 bit address helper function
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-11 18:54:59 +02:00
Sifan Naeem
c20821a7f0 i2c: img-scb: support repeated starts on IP v3.3
In version 3.3 of the IP when transaction halt is set, an interrupt
will be generated after each byte of a transfer instead of after
every transfer but before the stop bit.
Due to this behaviour we have to be careful that every time we
release the transaction halt we have to re-enable it straight away
so that we only process a single byte, not doing so will result in
all remaining bytes been processed and a stop bit being issued,
which will prevent us having a repeated start.

This change will have no effect on earlier versions of the IP.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:05:21 +01:00
Sifan Naeem
c7b0a7c107 i2c: img-scb: add handle for Master halt interrupt
Master halt is issued after each byte of a transaction is processed in
IP version 3.3.
Master halt will stall the bus by holding the SCK line low until the
halt bit in the scb_general_control is cleared.

After the last byte of a transfer is processed we can use the Master
Halt interrupt to facilitate a repeated start transfer without
issuing a stop bit.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:55 +01:00
Sifan Naeem
dd29207e6c i2c: img-scb: add handle for stop detected interrupt
Stop Detected interrupt is triggered when a Stop bit is detected on
the bus, which indicates the end of the current transfer.

When the end of a transfer is indicated by the Stop Detected interrupt,
drain the FIFO and signal completion for the transaction.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:30 +01:00
Sifan Naeem
a8c5a8d8c9 i2c: img-scb: remove fifo EMPTYING interrupts handle
Now that we are using the transaction halt interrupt to safely control
repeated start transfers, we no longer need to handle the fifo
emptying interrupts.

Handling this interrupt along with Transaction Halt interrupt can
cause erratic behaviour.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:04:05 +01:00
Sifan Naeem
c55ebe0e72 i2c: img-scb: support I2C_M_IGNORE_NAK
This commit adds support for the I2C_M_IGNORE_NAK protocol
modification.

Such behaviour can only be implemented in atomic mode. So, if a
transaction contains a message with such flag the drivers
switches to atomic mode. The implementation consists simply in
treating NAKs as ACKs.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:03:39 +01:00
Sifan Naeem
58b0497dad i2c: img-scb: verify support for requested bit rate
The requested bit rate can be outside the range supported by the driver.
The maximum bit rate this driver supports at the moment is 400Khz.

If the requested bit rate is larger than the maximum supported by the
driver, set the bitrate to the maximum supported before bitrate_khz is
calculated.

Maximum speed supported by the driver can be increased to 1Mhz by
adding support for "fast plus mode" in the future.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:40:11 +01:00
Sifan Naeem
1ed6faedfc i2c: img-scb: Clear line and interrupt status before starting a transfer
Clear line status and all generated interrupts from the interrupt
status register before starting a transfer, as we may have
unserviced interrupts from previous transfers that might be
handled in the context of the new transfer.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:39:45 +01:00
Sifan Naeem
0f0a318997 i2c: img-scb: use line_status instead of i2c->line_status
i2c->line_status accumulates the line status bits that have been seen
with each interrupt. As we're only interested in that bit from the
current interrupt, refer to line_status (the argument to img_i2c_auto)
instead of i2c->line_status.

Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:39:20 +01:00
Sifan Naeem
987008dbc4 i2c: img-scb: fix LOW and HIGH period values for the SCL clock
Currently, after determining the minimum value for the High period
(TCKH) the remainder of the internal clock pulses is set as the Low
period (TCKL). This causes the i2c clock duty cycle to be much less
than 50%.

Modify the starting position to TCKH and TCKL at 50% of the internal
clock, and adjusts the TCKH and TCKL values from there should the
minimum value for TCKL not be met. This results in duty cycles closer
to 50%.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:38:55 +01:00
Sifan Naeem
5728d95f24 i2c: img-scb: use DIV_ROUND_UP to round divisor values
Using % can be slow depending on the architecture.

Using DIV_ROUND_UP is nicer and more efficient way to do it.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:38:31 +01:00
Sifan Naeem
2aefb1bd41 i2c: img-scb: do dummy writes before fifo access
Move scb_wr_rd_fence to before reading from fifo and writing to
fifo to make sure the the first read/write is done after the required
number of cycles.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:38:06 +01:00
Sifan Naeem
0e59378bc0 i2c: img-scb: enable fencing for all versions of the ip
The code to read from the master read fifo, and write to the master
write fifo, checks a bit in an SCB register before every byte to
ensure that the fifo is not full (write fifo) or empty (read fifo).
Due to clock domain crossing inside the SCB block the updated value
of this bit is only visible after 2 cycles.

The scb_wr_rd_fence() function does 2 dummy writes (to the read-only
revision register), and it's called before reading from or writing to the
fifos to ensure that subsequent reads of the fifo status bits do not read
stale values.

As the 2 dummy writes are required in all versions of the ip, the version
check is dropped.

Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: James Hartley <james.hartley@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-10 08:37:41 +01:00
Nicholas Mc Guire
913b1d85cd i2c: img-scb: fixup of wait_for_completion_timeout return handling
Return type of wait_for_completion_timeout is unsigned long not int.
Appropriately typed/named variable are added and assignment fixed up.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-15 10:54:09 +01:00
James Hogan
27bce457d5 i2c: img-scb: Add Imagination Technologies I2C SCB driver
Add support for the IMG I2C Serial Control Bus (SCB) found on the
Pistachio and TZ1090 SoCs.

Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
[Ezequiel: code cleaning and rebasing]
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-17 19:54:24 +01:00