Userspace can initiate system suspend on arbitrary times which means that
device drivers must make sure that their device gets quiesced before system
suspend is entered. Therefore disable the I2C host controller in the driver
system suspend hook.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch allows to set independantly SCL and SDA falling times.
The tLOW period is computed by taking into account the SCL falling time.
The tHIGH period is computed by taking into account the SDA falling time.

For instance in case the margin on tLOW is considered too small, it can
be increased by increasing the SCL falling time which is by default set
at 300ns.

The same applies for tHIGH period with the help of SDA falling time.
Signed-off-by: NRomain Baeriswyl <romainba@abilis.com>
Reviewed-by: NChristian Ruppert <christian.ruppert@abilis.com>
Acked-by: NShinya Kuribayashi <skuribay@pobox.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Newer Intel PCHs with LPSS have the same Designware I2C controllers than
Haswell but the ACPI IDs differ. Add these IDs to the driver list.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.
Reported-by: NZhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some Intel LPSS I2C devices make the SDA hold time and *CNT parameters
available via SSCN (standard mode) and FMCN (fast mode) ACPI methods.

Implement support for this so that we check whether an ACPI method exists
and if it does, fill in the SDA hold time and *CNT values to the device
private structure for core to use.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This follows what has already been done for the DeviceTree helpers. Move
the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update
documentation accordingly.

This also solves a problem reported by Jerry Snitselaar that we can't build
the ACPI I2C helpers as a module.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following
build warning when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SIMPLE_DEV_PM_OPS are only used when
the CONFIG_PM_SLEEP is enabled.

drivers/i2c/busses/i2c-designware-platdrv.c:211:12: warning: 'dw_i2c_suspend' defined but not used [-Wunused-function]
drivers/i2c/busses/i2c-designware-platdrv.c:221:12: warning: 'dw_i2c_resume' defined but not used [-Wunused-function]
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This fixes the following link error:

  drivers/built-in.o: In function `dw_i2c_probe':
  of_iommu.c:(.text+0x18c8f0): undefined reference to `__aeabi_uldivmod'
  make: *** [vmlinux] Error 1
Signed-off-by: NVincent Stehlé <vincent.stehle@freescale.com>
Tested-by: NKevin Hilman <khilman@linaro.org>
Reviewed-by: NChristian Ruppert <christian.ruppert@abilis.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch makes the SDA hold time configurable through device tree.
Signed-off-by: NChristian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: NPierrick Hascoet <pierrick.hascoet@abilis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This is the same controller as on Intel Lynxpoint but the ACPI ID is
different (8086F41). Add support for this.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Driver core already takes care of refcounting, no need to do this on
driver level again.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Using autosuspend helps to reduce the resume latency in situations where
another I2C message is going to be started soon. For example with HID over
I2C touch panels we get several messages in a short period of time while
the touch panel is in use.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

It is not good idea to mix static and dynamic I2C adapter numbering. In
this particular case on Lynxpoint we had graphics I2C adapter which took
the first numbers preventing the designware I2C driver from using the
adapter numbers it preferred.

Since Lynxpoint support was just introduced and there is no hardware available
outside Intel we can fix this by switching to use dynamic adapter numbering
instead of static.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This makes the error handling much more simpler than open-coding everything
and in addition makes the probe function smaller and tidier.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The ACPI handle of struct i2c_adapter's dev member should not be
set, because this causes that struct i2c_adapter to be associated
with the ACPI device node corresponding to its parent as the
second "physical_device", which is incorrect (this happens during
the registration of struct i2c_adapter).  Consequently,
acpi_i2c_register_devices() should use the ACPI handle of the
parent of the struct i2c_adapter it is called for rather than the
struct i2c_adapter's ACPI handle (which should be NULL).

Make that happen and modify the i2c-designware-platdrv driver,
which currently is the only driver for ACPI-enumerated I2C
controller chips, not to set the ACPI handle for the
struct i2c_adapter it creates.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NAaron Lu <aaron.lu@intel.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>

There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases.  This is just extra
cruft code that can be removed.

A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
  dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
  twice.
* I verified that there were no cases where xxx_get_drvdata() was
  being called in these drivers and checking for / relying on the NULL
  return value.

This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.
Reported-by: NWolfram Sang <wsa@the-dreams.de>
Reported-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Reviewed-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NPeter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NWolfram Sang <wolfram@the-dreams.de>

Intel Lynxpoint has two I2C controllers. These controllers are enumerated
from ACPI namespace with IDs INT33C2 and INT33C3. Add support for these to
the I2C DesignWare platform driver.

This is based on the work of Dirk Brandewie.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

In order to save power the device should be put to low power states
whenever it is not being used. We implement this by enabling minimal
runtime PM support.

There isn't much to do for the device itself as it is disabled once the
last transfer is completed but subsystem/domain runtime PM hooks can save
more power by power gating the device etc.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

CONFIG_HOTPLUG is going away as an option.  As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: NJean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

clk_{un}prepare is mandatory for platforms using common clock framework. Since
this driver is used by SPEAr platform, which supports common clock framework,
add clk_{un}prepare() support for designware i2c.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

This patch adds in support for standby/S2R/hybernate for i2c-designware driver.
Signed-off-by: NDeepak Sikri <deepak.sikri@st.com>
Signed-off-by: NRajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

There are few drivers which are available on i2c bus but have been initialized
with subsys_initcall. Also as I2C is a bus driver, it should be available as
early as possible.
Signed-off-by: NPratyush Anand <pratyush.anand@st.com>
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>

[wsa: Slightly updated the commit message]
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

Add of_match_table and DT style i2c registration to designware i2c
driver.

Refactored for pci/plat split by Dirk Brandewie.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>

Move all register manipulation code into the core, also move register
offset definitions to i2c-designware-core.c since the bus specific
portions of the driver no longer need/use them.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

With multiple I2C adapters possible in the system each running at
(possibly) different speeds we need to move the controller
configuration bit field to the adapter.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The functionality of the adapter depends on the configuration of the
IP block at silicon compile time and is adapter specific.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The clock frequecy supplied to the IP core is specific to a single
instance of the driver.  This patch makes it possible to have multiple
Designware I2C cores in the system possibly running at different core
frequencies.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This patch splits i2c-designware.c into three pieces:
     i2c-designware-core.c, contains the code that interacts directly
     with the core.

     i2c-designware-platdrv.c, contains the code specific to the
     platform driver using the core.

     i2c-designware-core.h contains the definitions and declareations
     shared by i2c-designware-core.c and i2c-designware-platdrv.c.

This patch is the first in a set to allow multiple instances of the
designware I2C core in the system.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>