There are few maximum bus frequencies being used in the I²C core code.
Provide generic definitions for bus frequencies and use them in the core.

The drivers may use predefined constants where it is appropriate.
Some of them are already using these under slightly different names.
We will convert them later to use newly introduced defines.

Note, the name of modes are chosen to follow well established naming
scheme [1].

These definitions will also help to avoid typos in the numbers that
may lead to subtle errors.

[1]: https://en.wikipedia.org/wiki/I%C2%B2C#Differences_between_modesAcked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We don't need dev_err() message because when something goes wrong,
platform_get_irq() has print an error message itself, so we should
remove duplicate dev_err().
Signed-off-by: NTang Bin <tangbin@cmss.chinamobile.com>
Acked-by: NOleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Fix spelling typos in the comments with help of `codespell`.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is no code left in the kernel which would be using the function.
So just remove it.
Signed-off-by: NSerge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: NAlexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The problem with detecting the FIFO depth in the platform driver
is that in order to implement this we have to access the controller
IC_COMP_PARAM_1 register. Currently it's done before the
i2c_dw_set_reg_access() method execution, which is errors prone since
the method determines the registers endianness and access mode and we
can't use dw_readl/dw_writel accessors before this information is
retrieved. We also can't move the i2c_dw_set_reg_access() function
invocation to after the master/slave probe functions call (when endianness
and access mode are determined), since the FIFO depth information is used
by them for initializations. So in order to fix the problem we have no
choice but to move the FIFO size detection methods to the common code and
call it at the probe stage.
Signed-off-by: NSerge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: NAlexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The struct cdev is embedded in the struct i2c_dev. In the current code,
we would free the i2c_dev struct directly in put_i2c_dev(), but the
cdev is manged by a kobject, and the release of it is not predictable.
So it is very possible that the i2c_dev is freed before the cdev is
entirely released. We can easily get the following call trace with
CONFIG_DEBUG_KOBJECT_RELEASE and CONFIG_DEBUG_OBJECTS_TIMERS enabled.
  ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x38
  WARNING: CPU: 19 PID: 1 at lib/debugobjects.c:325 debug_print_object+0xb0/0xf0
  Modules linked in:
  CPU: 19 PID: 1 Comm: swapper/0 Tainted: G        W         5.2.20-yocto-standard+ #120
  Hardware name: Marvell OcteonTX CN96XX board (DT)
  pstate: 80c00089 (Nzcv daIf +PAN +UAO)
  pc : debug_print_object+0xb0/0xf0
  lr : debug_print_object+0xb0/0xf0
  sp : ffff00001292f7d0
  x29: ffff00001292f7d0 x28: ffff800b82151788
  x27: 0000000000000001 x26: ffff800b892c0000
  x25: ffff0000124a2558 x24: 0000000000000000
  x23: ffff00001107a1d8 x22: ffff0000116b5088
  x21: ffff800bdc6afca8 x20: ffff000012471ae8
  x19: ffff00001168f2c8 x18: 0000000000000010
  x17: 00000000fd6f304b x16: 00000000ee79de43
  x15: ffff800bc0e80568 x14: 79616c6564203a74
  x13: 6e6968207473696c x12: 5f72656d6974203a
  x11: ffff0000113f0018 x10: 0000000000000000
  x9 : 000000000000001f x8 : 0000000000000000
  x7 : ffff0000101294cc x6 : 0000000000000000
  x5 : 0000000000000000 x4 : 0000000000000001
  x3 : 00000000ffffffff x2 : 0000000000000000
  x1 : 387fc15c8ec0f200 x0 : 0000000000000000
  Call trace:
   debug_print_object+0xb0/0xf0
   __debug_check_no_obj_freed+0x19c/0x228
   debug_check_no_obj_freed+0x1c/0x28
   kfree+0x250/0x440
   put_i2c_dev+0x68/0x78
   i2cdev_detach_adapter+0x60/0xc8
   i2cdev_notifier_call+0x3c/0x70
   notifier_call_chain+0x8c/0xe8
   blocking_notifier_call_chain+0x64/0x88
   device_del+0x74/0x380
   device_unregister+0x54/0x78
   i2c_del_adapter+0x278/0x2d0
   unittest_i2c_bus_remove+0x3c/0x80
   platform_drv_remove+0x30/0x50
   device_release_driver_internal+0xf4/0x1c0
   driver_detach+0x58/0xa0
   bus_remove_driver+0x84/0xd8
   driver_unregister+0x34/0x60
   platform_driver_unregister+0x20/0x30
   of_unittest_overlay+0x8d4/0xbe0
   of_unittest+0xae8/0xb3c
   do_one_initcall+0xac/0x450
   do_initcall_level+0x208/0x224
   kernel_init_freeable+0x2d8/0x36c
   kernel_init+0x18/0x108
   ret_from_fork+0x10/0x1c
  irq event stamp: 3934661
  hardirqs last  enabled at (3934661): [<ffff00001009fa04>] debug_exception_exit+0x4c/0x58
  hardirqs last disabled at (3934660): [<ffff00001009fb14>] debug_exception_enter+0xa4/0xe0
  softirqs last  enabled at (3934654): [<ffff000010081d94>] __do_softirq+0x46c/0x628
  softirqs last disabled at (3934649): [<ffff0000100b4a1c>] irq_exit+0x104/0x118

This is a common issue when using cdev embedded in a struct.
Fortunately, we already have a mechanism to solve this kind of issue.
Please see commit 233ed09d ("chardev: add helper function to
register char devs with a struct device") for more detail.

In this patch, we choose to embed the struct device into the i2c_dev,
and use the API provided by the commit 233ed09d to make sure that
the release of i2c_dev and cdev are in sequence.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This driver doesn't call any DT platform functions like of_platform_*().
Remove the include as it isn't used.
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NBrendan Higgins <brendanhiggins@google.com>
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: NAmit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some lines are long here. Use a struct dev pointer to shorten lines and
simplify code. The clk_get() call can fail because of EPROBE_DEFER
problems too, so just remove the error print message because it isn't
useful. Finally, platform_get_irq() already prints an error so just
remove that error message.
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NBrendan Higgins <brendanhiggins@google.com>
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: NAmit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We don't need to force IRQF_TRIGGER_HIGH here as the DT or ACPI tables
should take care of this for us. Just use 0 instead so that we use the
flags from the firmware. Also, remove specify dev_name() for the irq
name so that we can get better information in /proc/interrupts about
which device is generating interrupts.

Cc: Alok Chauhan <alokc@codeaurora.org>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NBrendan Higgins <brendanhiggins@google.com>
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: NAmit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The PECR register provides received packet computed PEC value. 
It makes no sense restoring its value after a reset, and anyway,
as read-only register it cannot be restored.

Fixes: ea6dd25d ("i2c: stm32f7: add PM_SLEEP suspend/resume support")
Signed-off-by: NAlain Volmat <alain.volmat@st.com>
Reviewed-by: NPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

IRQ levels are now handled within the IRQ core. Remove the forgotten
references from the documentation.

Fixes: 9b9f2b8b ("i2c: i2c-smbus: Use threaded irq for smbalert")
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NLuca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Only few drivers use this call, so drivers and I2C core are converted at
once with this patch. By simply using i2c_new_client_device() instead of
i2c_new_device(), we easily can return an ERRPTR for this function as
well. To make out of tree users aware that something changed, the
function is renamed to i2c_new_smbus_alert_device().
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NLuca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add a new stm32mp15 specific compatible to handle FastMode+
registers handling which is different on the stm32mp15 compared
to the stm32f7 or stm32h7.
Indeed, on the stm32mp15, the FastMode+ set and clear registers
are separated while on the other platforms (F7 or H7) the control
is done in a unique register.
Signed-off-by: NAlain Volmat <alain.volmat@st.com>
Reviewed-by: NPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Defer the initial enabling of the Fast Mode Plus bits after the
stm32f7_i2c_setup_timing call in probe function in order to avoid
enabling them if speed is downgraded.
Clear & restore the Fast Mode Plus bits in the suspend/resume
handlers of the driver.
Signed-off-by: NAlain Volmat <alain.volmat@st.com>
Reviewed-by: NPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The HDMI blocks in the BCM2771 have an i2c controller to retrieve the
EDID. This block is split into two parts, the BSC and the AUTO_I2C,
lying in two separate register areas.

The AUTO_I2C block has a mailbox-like interface and will take away the
BSC control from the CPU if enabled. However, the BSC is the actually
the same controller than the one supported by the brcmstb driver, and
the AUTO_I2C doesn't really bring any immediate benefit.

Let's use the BSC then, but let's also tie the AUTO_I2C registers with a
separate compatible so that we can enable AUTO_I2C if needed in the
future.

The AUTO_I2C is enabled by default at boot though, so we first need to
release the BSC from the AUTO_I2C control.

Cc: Kamal Dasu <kdasu.kdev@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: linux-i2c@vger.kernel.org
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Use a new API devm_platform_ioremap_resource() to simplify code.
Signed-off-by: Nchenqiwu <chenqiwu@xiaomi.com>
Tested-by: NLuca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: NLuca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: NVignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Use kobj_to_dev() API instead of container_of().
Signed-off-by: Nchenqiwu <chenqiwu@xiaomi.com>
Reviewed-by: NLuca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The comment had some flaws which are now fixed:
- the prefix is 'MAC' not 'AAPL'
- no kernel coding style and too short length
- 'we do' instead of 'we to'
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Allow the i2c-stm32f7 controller to become a wakeup-source
of the system. In such case, when a slave is registered to the
I2C controller, receiving a I2C message targeting that registered
slave address wakes up the suspended system.

In order to be able to wake-up, the I2C controller DT node
must have the property wakeup-source defined and a slave
must be registered.
Signed-off-by: NAlain Volmat <alain.volmat@st.com>
Reviewed-by: NPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rework the read and write code paths in the driver to support operation
in atomic contexts. To achieve this, the driver must not rely on IRQs
and not call schedule(), e.g. via a sleep routine, in these cases.

With this patch the driver supports normal operation, DMA transfers and
now the polling mode or also called sleep-free or IRQ-less operation. It
makes the code not simpler or easier to read, but atomic I2C transfers
are needed on some hardware configurations, e.g. to trigger reboots on
an external PMIC chip.
Signed-off-by: NStefan Lengfeld <contact@stefanchrist.eu>
[m.felsch@pengutronix.de: integrate https://patchwork.ozlabs.org/patch/1085943/ review feedback]
[m.felsch@pengutronix.de: adapt commit message]
Signed-off-by: NMarco Felsch <m.felsch@pengutronix.de>
Acked-by: NOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: NStefan Agner <stefan@agner.ch>
Tested-by: NStefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Implement i2c bus recovery when slaves devices might hold SDA low.
In this case re-assign SCL/SDA to gpios and issue 9 dummy clock pulses
until the slave release SDA.
Signed-off-by: NKamel Bouhara <kamel.bouhara@bootlin.com>
Signed-off-by: NCodrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: NLudovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

'PTR_ERR(p) == -E*' is a stronger condition than IS_ERR(p).
Hence, IS_ERR(p) is unneeded.

The semantic patch that generates this commit is as follows:

// <smpl>
@@
expression ptr;
constant error_code;
@@
-IS_ERR(ptr) && (PTR_ERR(ptr) == - error_code)
+PTR_ERR(ptr) == - error_code
// </smpl>

Link: http://lkml.kernel.org/r/20200106045833.1725-1-masahiroy@kernel.orgSigned-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Stephen Boyd <sboyd@kernel.org> [drivers/clk/clk.c]
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> [GPIO]
Acked-by: Wolfram Sang <wsa@the-dreams.de> [drivers/i2c]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [acpi/scan.c]
Acked-by: NRob Herring <robh@kernel.org>
Cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add ACPI HID HISI02A3 for Hisilicon Hip08 Lite, which has different
clock frequency from Hip08 for I2C controller.
Tested-by: NSheng Feng <fengsheng5@huawei.com>
Signed-off-by: NHanjun Guo <guohanjun@huawei.com>
Acked-by: NNikula <jarkko.nikula@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The initial patch was using the incorrect identifier.

Fixes: 9af1563a ("i2c: cros-ec-tunnel: Make the device acpi compatible")
Signed-off-by: NRaul E Rangel <rrangel@chromium.org>
Acked-by: NEnric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

During adding of the adapter the slave device registration
use to fail as the acpi companion field was not populated.

Fixes: 9af1563a ("i2c: cros-ec-tunnel: Make the device acpi compatible")
Signed-off-by: NAkshu Agrawal <akshu.agrawal@amd.com>
Acked-by: NRaul E Rangel <rrangel@chromium.org>
Reviewed-by: NEnric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Backup/restore I2C registers as part of the suspend/resume
handlers. The device is marked as suspended to ensure that
transfers are rejected during the suspended period.
Signed-off-by: NPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: NAlain Volmat <alain.volmat@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Fix wording based on checkpatch.pl
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

E.g. pm_runtime_set_active must be called while the power
management system is disabled. Fixes extra hanging clk_enable.
Signed-off-by: NTopi Kuutela <topi.kuutela@gmail.com>
Acked-by: NSören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Do not print error in case of EPROBE_DEFER.
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Under certain conditions, Cadence's I2C controller's transfer_size
register will roll over and generate invalid read transactions. Before
this change, the ISR relied solely on the RXDV bit to determine when to
write more data to the user's buffer. The invalid read data would cause
overruns, smashing stacks and worse.

This change stops the buffer writes to the requested boundary and
reports the error. The controller will be reset so normal transactions
may resume.
Signed-off-by: NAlex Williams <alex.williams@ni.com>
Reviewed-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com> # in a seperate mail
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add support for Intel Comet Lake PCH-V which is based on Intel Kaby
Lake. Difference between it and other Comet Lake variants is that former
uses previous iTCO version 4 and latter use version 6 like Intel Cannon
Lake PCH.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is a statement that is indented one level too deeply, remove
the extraneous tab.

Fixes: b4c119db ("i2c: xiic: Add timeout to the rx fifo wait loop")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NShubhrajyoti Datta <shubhrajyoti.datta@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is a spelling mistake in a module parameter description.
Fix it.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Update the help text to reflect current support devices:
1. The Exynos high speed I2C driver supports Exynos5 (ARMv7), Exynos5433
   and Exynos7 (both ARMv8) SoCs,
2. The S3C I2C driver supports S3C, S5Pv210 and Exynos{3,4,5} SoCs.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some of the I2C bus drivers can be compile tested to increase build
coverage.  This requires also:
1. Adding dependencies on COMMON_CLK for BCM2835 and Meson I2C
   controllers,
2. Adding 'if' conditional to 'default y' so they will not get enabled
   by default on all other architectures,
3. Limiting few compile test options to supported architectures (which
   provide the readsX()/writesX() primitives).
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
[wsa: revert chunk for ZX2967. it needs more preparation]
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The recommendation is that the set_active should be done
with pm runtime disabled.
Also fix the remove path for clocking.
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

It's not always the case that clock is already available when i2c
driver get probed at the first time, e.g. the clock is provided by
clock wizard which may be probed after i2c driver. So let's defer
the probe when devm_clk_get() call fails and give it chance to
try later.
Signed-off-by: NVenkatesh Yadav Abbarapu <venkatesh.abbarapu@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add timeout to the rx fifo empty wait loop. Also check for the return
value for xiic_reinit and pass it to xiic_start_xfer.
Signed-off-by: NShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>