Although I2C mux devices are easily enumerated using ACPI (_HID/_CID or
device property compatible string match), enumerating I2C client devices
connected through an I2C mux needs a little extra work.

This change implements a method for describing an I2C device hierarchy that
includes mux devices by using an ACPI Device() for each mux channel along
with an _ADR to set the channel number for the device.  See
Documentation/acpi/i2c-muxes.txt for a simple example.

To make this work the ismt, i801, and designware pci/platform devs now
share an ACPI companion with their I2C adapter dev similar to how it's done
in OF.  This is done on the assumption that power management functions will
not be called directly on the I2C dev that is sharing the ACPI node.
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NDustin Byford <dustin@cumulusnetworks.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch adds the SMBUS PCI ID of Intel Broxton.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Intel DNV SoC has the same legacy SMBus host controller than Intel
Sunrisepoint PCH. It also has same iTCO watchdog on the bus.

Add DNV PCI ID to the list of supported devices.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Starting from Intel Sunrisepoint (Skylake PCH) the iTCO watchdog resources
have been moved to reside under the i801 SMBus host controller whereas
previously they were under the LPC device.

In order to support the iTCO watchdog on newer PCHs we need to create the
platform device here in the SMBus driver and pass all known resources using
platform data.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

Simplifies the code a bit and makes easier to disable PCI device on driver
detach by removing the pcim_pin_device() call in the future if needed.

Reason why i2c-i801.c doesn't ever call pci_disable_device() was because it
made some systems to hang during power-off. See commit d6fcb3b9
("[PATCH] i2c-i801.c: don't pci_disable_device() after it was just enabled")
and
http://marc.info/?l=linux-kernel&m=115160053309535&w=2Signed-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>

Since pci_disable_device() is not called from i801_suspend() and power
state is set already it means that subsequent pci_enable_device() calls do
practically nothing but monotonically increase struct pci_dev enable_cnt.
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>

This simplifies the error and remove paths.
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>

struct pci_driver i801_driver forward declaration is needed only for
accessing the name field. Remove it and use dev_driver_string() instead.
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>

It makes more difficult to grep these error prints from sources if they are
split to multiple source lines.
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>

Signed-off-by: NDevin Ryles <devin.ryles@intel.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Don't log the host status register value in i801_isr(), it has very
little value and fills up the log when debugging is enabled.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is a control bit in the PCI configuration space which disables
interrupts. If this bit is set, the driver should not try to make use
of interrupts, it won't receive any.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i2c-i801 driver can work without interrupts, so there is no reason
to make a request_irq failure fatal. Instead we can simply fallback
to polling.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some systems have been reported to have trouble with interrupts. Use
wait_event_timeout() instead of wait_event() so we don't get stuck in
that case, and log the problem.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We have a central copy of the GPL for that. Some addresses were already
outdated.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>

This patch adds the I2C/SMBus Device IDs for the Intel Sunrise Point PCH.
Signed-off-by: NJames Ralston <james.d.ralston@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The SMBus host controller is the same as used in Baytrail so add the new
PCI ID to the driver's list of supported IDs.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A long name broke the alignment, shift the columns a bit to fix it and
make the table look nice again. While we're here, switch to the
standard comment style to make checkpatch happy, and use tabs instead
of spaces for column alignment.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Don't use DEFINE_PCI_DEVICE_TABLE macro, because this macro
is not preferred.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add Device ID of Intel BayTrail SMBus Controller.
Signed-off-by: NChew, Kean ho <kean.ho.chew@intel.com>
Signed-off-by: NChew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NJean Delvare <khali@linux-fr.org>

This patch adds the SMBus Device IDs for the Intel Wildcat Point-LP PCH.
Signed-off-by: NJames Ralston <james.d.ralston@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>

This patch adds the i801 SMBus Controller DeviceIDs for the Intel Coleto Creek PCH.
Signed-off-by: NSeth Heasley <seth.heasley@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Duplicate the feature bits documentation in modinfo, as not every user
will read the driver's source code or documentation file.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-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>

This patch adds the SMBus Device IDs for the Intel Wellsburg PCH
Signed-off-by: NJames Ralston <james.d.ralston@intel.com>
Reviewed-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NWolfram Sang <wolfram@the-dreams.de>

This patch adds the PCU SMBus DeviceID for the Intel Avoton SOC.
Signed-off-by: NSeth Heasley <seth.heasley@intel.com>
Reviewed-by: NJean Delvare <khali@linux-fr.org>
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>

I did not receive a single bug report after interrupt support was
added for a limited number of chips. So I'd say the code is good and
should be enabled for all supported chips, that is: ICH5 and later.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Reviewed-by: NDaniel Kurtz <djkurtz@chromium.org>

Add support for probing slave devices parsed from the device tree.
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Signed-off-by: NJean Delvare <khali@linux-fr.org>

Arbitrarily selecting GPIOLIB causes trouble on some architectures,
so don't do that. Instead, just make the optional multiplexing code
depend on CONFIG_I2C_MUX_GPIO instead of CONFIG_I2C_MUX for now. We
can revisit if the i2c-i801 driver ever supports other multiplexing
flavors.

Also make that optional code depend on DMI, as it won't do anything
without that.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>

Now that i2c-mux-gpio is able to find the GPIO chip by itself, we can
delegate this task. The great thing here is that i2c-mux-gpio can
defer device probing until the gpio chip is available, so we no longer
depend on the module loading order.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Add support for SMBus multiplexing on Asus Z8 motherboard series. On
these boards, the memory slots are behind a GPIO-controlled I2C
multiplexer. Models with 6 or 12 memory slots have 2 segments behind
the multiplexer, while models with 18 memory slots have 3 such
segments.

On these boards, only the memory slots are behind the multiplexer,
so it is possible to keep the autodetection mechanism.

The code is generic enough so it could work on other boards as long as
the multiplexer is controlled by GPIO pins. For other forms of
multiplexing (for example using an I2C device) additional code will be
needed.

Thanks to Asus for providing a board to develop and test this feature,
as well as all the technical information required.

At the moment, the GPIO driver must be loaded before the i2c-i801
driver, but I hope to solve this soon, using deferred probing on
the i2c-mux-gpio side.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Add the SMBus Device IDs for the Intel Lynx Point-LP PCH.
Signed-off-by: NJames Ralston <james.d.ralston@intel.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Byte-by-byte transactions are used primarily for accessing I2C devices
with an SMBus controller.  For these transactions, for each byte that is
read or written, the SMBus controller generates a BYTE_DONE IRQ.  The isr
reads/writes the next byte, and clears the IRQ flag to start the next byte.
On the penultimate IRQ, the isr also sets the LAST_BYTE flag.

There is no locking around the cmd/len/count/data variables, since the
I2C adapter lock ensures there is never multiple simultaneous transactions
for the same device, and the driver thread never accesses these variables
while interrupts might be occurring.

The end result is faster I2C block read and write transactions.

Note: This patch has only been tested and verified by doing I2C read and
write block transfers on Cougar Point 6 Series PCH, as well as I2C read
block transfers on ICH5.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Enable interrupts on more devices. ICH5, ICH7(-M) and ICH10 have been
tested to work OK. ICH8 and ICH9 are expected to work just fine as
they are very close to ICH7 and ICH10.

Ultimately we want to enable this feature on at least every device
since the ICH5, but for now we limit the exposure. We'll enable it for
other devices if we don't get negative feedback.

As a bonus, let the user know when interrupts are used.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Daniel Kurtz <djkurtz@chromium.org>

Add a new 'feature' to i2c-i801 to enable using PCI interrupts.
When the feature is enabled, then an isr is installed for the device's
PCI IRQ.

An I2C/SMBus transaction is always terminated by one of the following
interrupt sources: FAILED, BUS_ERR, DEV_ERR, or on success: INTR.

When the isr fires for one of these cases, it sets the ->status variable
and wakes up the waitq.  The waitq then saves off the status code, and
clears ->status (in preparation for some future transaction).
The SMBus controller generates an INTR irq at the end of each
transaction where INTREN was set in the HST_CNT register.

No locking is needed around accesses to priv->status since all writes to
it are serialized: it is only ever set once in the isr at the end of a
transaction, and cleared while no interrupts can occur.  In addition, the
I2C adapter lock guarantees that entire I2C transactions for a single
adapter are always serialized.

For this patch, the INTREN bit is set only for SMBus block, byte and word
transactions, but not for I2C reads or writes.  The use of the DS
(BYTE_DONE) interrupt with byte-by-byte I2C transactions is implemented in
a subsequent patch.

The interrupt feature has only been enabled for COUGARPOINT hardware.
In addition, it is disabled if SMBus is using the SMI# interrupt.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Signed-off-by: NJean Delvare <khali@linux-fr.org>