Commit graph

210 commits

Author SHA1 Message Date
Peter Rosin
c99a23e55f i2c: mux: pinctrl: stop double error reporting
i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-04-03 14:07:34 +02:00
Peter Rosin
0756ac3235 i2c: mux: pca954x: stop double error reporting
i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-04-03 14:07:33 +02:00
Peter Rosin
664d9bbada i2c: mux: pca9541: stop double error reporting
i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-04-03 14:07:33 +02:00
Peter Rosin
1b00900fa0 i2c: mux: gpio: stop double error reporting
i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-04-03 14:07:32 +02:00
Peter Rosin
1144d13eaa i2c: arb: gpio-challenge: stop double error reporting
i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-04-03 14:07:32 +02:00
Mike Looijmans
dbe4d69d25 i2c: mux: pca954x: Add missing pca9546 definition to chip_desc
The spec for the pca9546 was missing. This chip is the same as the pca9545
except that it lacks interrupt lines. While the i2c_device_id table mapped
the pca9546 to the pca9545 definition the compatible table did not.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-03-24 12:22:18 +01:00
Andy Shevchenko
e88162f9da Revert "i2c: mux: pca954x: Add ACPI support for pca954x"
In ACPI world any ID should be carefully chosen and registered
officially. The commit bbf9d262a1 seems did a wrong assumption because
PCA is the registered PNP ID for "PHILIPS BU ADD ON CARD". I'm pretty
sure this prefix has nothing to do with the driver in question.

Moreover, newer ACPI specification has a support of _DSD method and
special device IDs to allow drivers be enumerated via compatible string.
The slight change to support this kind of enumeration will be added in
sequential patch against pca954x.c.

Revert the commit bbf9d262a1 for good.

Cc: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-03-23 22:12:22 +01:00
Julia Cartwright
743cc37561 i2c: mux: pca954x: make use of raw_spinlock variants
The pca954x i2c mux driver currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel.  Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.

A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.

Signed-off-by: Julia Cartwright <julia@ni.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-03-15 23:22:43 +01:00
Wolfram Sang
465b2c4ab8 Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-4.11 2017-02-10 12:51:23 +01:00
Phil Reid
f2114795f7 i2c: mux: pca954x: Add interrupt controller support
Various muxes can aggregate multiple interrupts from each i2c bus.
All of the muxes with interrupt support combine the active low irq lines
using an internal 'and' function and generate a combined active low
output. The muxes do provide the ability to read a control register to
determine which irq is active. By making the mux an irq controller isr
latency can potentially be reduced by reading the status register and
then only calling the registered isr on that bus segment.

As there is no irq masking on the mux irq are disabled until irq_unmask is
called at least once.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-02-10 08:23:51 +01:00
Phil Reid
f8251f1dfd i2c: mux: pca954x: Add missing pca9542 definition to chip_desc
The spec for the pca954x was missing. This chip is the same as the pca9540
except that it has interrupt lines. While the i2c_device_id table mapped
the pca9542 to the pca9540 definition the compatible table did not. In
preparation for irq support add the pca9542 definition.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter Rosin <peda@axentia.se>
2017-02-10 08:23:50 +01:00
Javier Martinez Canillas
e278d64190 i2c: mux: pca9541: Export OF device ID table as module aliases
The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:31:05 +01:00
Javier Martinez Canillas
acf6ef1d6c i2c: mux: pca954x: Export OF device ID table as module aliases
The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:31:05 +01:00
Wei Yongjun
1da8726700 i2c: mux: mlxcpld: remove unused including <linux/version.h>
Remove including <linux/version.h> that don't need it.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:29:21 +01:00
Peter Rosin
649ac63a9a i2c: mux: mlxcpld: fix i2c mux selection caching
smbus functions return -ve on error, 0 on success.  However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater).

The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.

Fix this by making mlxcpld_mux_reg_write() return a -ve error code for
all failure cases, just as was done in commit 7f638c1cb0 ("i2c: mux:
pca954x: fix i2c mux selection caching").

This also aligns the implementations of these two muxes in this area.

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-12-18 08:54:38 +01:00
Russell King
7f638c1cb0 i2c: mux: pca954x: fix i2c mux selection caching
smbus functions return -ve on error, 0 on success.  However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater.)

The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.

Fix this by making pca954x_reg_write() return a negative error code for
all failure cases.

Fixes: 463e8f845c ("i2c: mux: pca954x: retry updating the mux selection on failure")
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-12-17 19:29:44 +01:00
Linus Torvalds
8600b697cd Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - the first series of making i2c_device_id optional instead of
   mandatory (in favor of alternatives like of_device_id).

   This involves adding a new probe callback (probe_new) which removes
   some peculiarities I2C had for a long time now. The new probe is
   matching the other subsystems now and the old one will be removed
   once all users are converted. It is expected to take a while but
   there is ongoing interest in that.

 - SMBus Host Notify introduced 4.9 got refactored. They are now using
   interrupts instead of the alert callback which solves multiple
   issues.

 - new drivers for iMX LowPower I2C, Mellanox CPLD and its I2C mux

 - significant refactoring for bcm2835 driver

 - the usual set of driver updates and improvements

* 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (46 commits)
  i2c: fsl-lpi2c: read lpi2c fifo size in probe()
  i2c: octeon: thunderx: Remove double-check after interrupt
  i2c: octeon: thunderx: TWSI software reset in recovery
  i2c: cadence: Allow Cadence I2C to be selected for Cadence Xtensa CPUs
  i2c: sh_mobile: Add per-Generation fallback bindings
  i2c: rcar: Add per-Generation fallback bindings
  i2c: imx-lpi2c: add low power i2c bus driver
  dt-bindings: i2c: imx-lpi2c: add devicetree bindings
  i2c: designware-pcidrv: Add 10bit address feature to medfield/merrifield
  i2c: pxa: Add support for the I2C units found in Armada 3700
  i2c: pxa: Add definition of fast and high speed modes via the regs layout
  dt-bindings: i2c: pxa: Update the documentation for the Armada 3700
  i2c: qup: support SMBus block read
  i2c: qup: add ACPI support
  i2c: designware: Consolidate default functionality bits
  i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep
  i2c: mux: pca954x: Add ACPI support for pca954x
  i2c: use an IRQ to report Host Notify events, not alert
  i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0
  i2c: i801: use the BIT() macro for FEATURES_* also
  ...
2016-12-15 12:56:35 -08:00
Peter Rosin
feff5c0a27 i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep
If the gpio controller supports it and the gpio lines are concentrated
to one gpio chip, the mux controller pins will get updated simultaneously.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-29 20:10:59 +01:00
tnhuynh@apm.com
bbf9d262a1 i2c: mux: pca954x: Add ACPI support for pca954x
This patch enables ACPI support for mux-pca954x driver.

Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Acked-by: Peter Rosin <peda@axentia.se>
[wsa: removed a trailing whitespace]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-29 20:06:47 +01:00
Alex Hemme
ad092de60f i2c: i2c-mux-pca954x: fix deselect enabling for device-tree
Deselect functionality can be ignored for device-trees with
"i2c-mux-idle-disconnect" entries if no platform_data is available.
By enabling the deselect functionality outside the platform_data
block the logic works as it did in previous kernels.

Fixes: 7fcac98071 ("i2c: i2c-mux-pca954x: convert to use an explicit i2c mux core")
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Alex Hemme <ahemme@cisco.com>
Signed-off-by: Ziyang Wu <ziywu@cisco.com>
[touched up a few minor issues /peda]
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-19 21:49:29 +01:00
Vadim Pasternak
c02b7bf532 i2c: mux: mellanox: add driver
This driver allows I2C routing controlled through CPLD select registers on
a wide range of Mellanox systems (CPLD Lattice device).
MUX selection is provided by digital and analog HW. Analog part is not
under SW control.
Digital part is under CPLD control (channel selection/de-selection).

Connectivity schema.
.---.             .-------------.
| l |             |             |-- i2cx1 -- i2cx8
| i |-- i2cn --+--| mlxcpld mux |
| n |          |  |             |-- i2cy1 -- i2cy8
| u |          |  '-------------'
| x |          |         |
'---'          '---------'

i2c-mux-mlxpcld does not necessarily require i2c-mlxcpld. It can be used
along with another bus driver, and still control i2c routing through CPLD
mux selection, in case the system is equipped with CPLD capable of mux
selection control.

The Kconfig currently controlling compilation of this code is:
drivers/i2c/muxes/Kconfig:config I2C_MUX_MLXCPLD

Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17 23:19:00 +01:00
Linus Walleij
93d710a65e i2c: mux: fix up dependencies
We get the following build error from UM Linux after adding
an entry to drivers/iio/gyro/Kconfig that issues "select I2C_MUX":

ERROR: "devm_ioremap_resource"
   [drivers/i2c/muxes/i2c-mux-reg.ko] undefined!
ERROR: "of_address_to_resource"
   [drivers/i2c/muxes/i2c-mux-reg.ko] undefined!

It appears that the I2C mux core code depends on HAS_IOMEM
for historical reasons, while CONFIG_I2C_MUX_REG does *not*
have a direct dependency on HAS_IOMEM.

This creates a situation where a allyesconfig or allmodconfig
for UM Linux will select I2C_MUX, and will implicitly enable
I2C_MUX_REG as well, and the compilation will fail for the
register driver.

Fix this up by making I2C_MUX_REG depend on HAS_IOMEM and
removing the dependency from I2C_MUX.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Jonathan Cameron <jic23@jic23.retrosnub.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-11-14 18:23:30 +01:00
Wolfram Sang
d052db11c1 i2c: mux: demux-pinctrl: make drivers with no pinctrl work again
Some drivers like i2c-gpio do not have dedicated pinctrl states. They
broke when error checking for pinctrl was added. Detect them now, and in
their case, simply skip over pinctrl configuration.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-10 21:12:47 +01:00
Linus Torvalds
87840a2b7e Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Here is the 4.9 pull request from I2C including:

   - centralized error messages when registering to the core
   - improved lockdep annotations to prevent false positives
   - DT support for muxes, gates, and arbitrators
   - bus speeds can now be obtained from ACPI
   - i2c-octeon got refactored and now supports ThunderX SoCs, too
   - i2c-tegra and i2c-designware got a bigger bunch of updates
   - a couple of standard driver fixes and improvements"

* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
  i2c: axxia: disable clks in case of failure in probe
  i2c: octeon: thunderx: Limit register access retries
  i2c: uniphier-f: fix misdetection of incomplete STOP condition
  gpio: pca953x: variable 'id' was used twice
  i2c: i801: Add support for Kaby Lake PCH-H
  gpio: pca953x: fix an incorrect lockdep warning
  i2c: add a warning to i2c_adapter_depth()
  lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
  i2c: export i2c_adapter_depth()
  i2c: rk3x: Fix variable 'min_total_ns' unused warning
  i2c: rk3x: Fix sparse warning
  i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
  i2c: octeon: Fix high-level controller status check
  i2c: octeon: Avoid sending STOP during recovery
  i2c: octeon: Fix set SCL recovery function
  i2c: rcar: add support for r8a7796 (R-Car M3-W)
  i2c: imx: make bus recovery through pinctrl optional
  i2c: meson: add gxbb compatible string
  i2c: uniphier-f: set the adapter to master mode when probing
  i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
  ...
2016-10-07 14:12:21 -07:00
Peter Rosin
463e8f845c i2c: mux: pca954x: retry updating the mux selection on failure
The cached value of the last selected channel prevents retries on the
next call, even on failure to update the selected channel. Fix that.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-09-21 23:10:21 +02:00
Wolfram Sang
e35478eac0 i2c: mux: demux-pinctrl: run properly with multiple instances
We can't use a static property for all the changesets, so we now create
dynamic ones for each changeset.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Fixes: 50a5ba8769 ("i2c: mux: demux-pinctrl: add driver")
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 16:56:21 +02:00
Peter Rosin
8a191a7ad4 i2c: pca954x: add device tree binding
No longer rely on the implicit matching with the i2c device name, use
an explicit compatible string instead.

Keep a direct pointer to the chip description instead of an index into
the chip description array.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2016-08-25 22:11:04 +02:00
Peter Rosin
a1cbf338ab i2c: pca9541: add device tree binding
No longer rely on the implicit matching with the i2c device name, use
an explicit compatible string instead.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2016-08-25 22:11:03 +02:00
Peter Rosin
40839590f8 i2c: mux: inform the i2c mux core about how it is used
The i2c mux core can then take appropriate action depending on if it is
used for an actual i2c mux, for a gate or for an arbitrator (the last
is the case for these drivers). This adds support for the new clearer
and more compact devicetree bindings that was added recently.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2016-08-25 22:11:03 +02:00
Wolfram Sang
9a5382e8ff i2c: mux: demux-pinctrl: invalidate properly when switching fails
Make sure the index to the active channel is invalidated when switching
fails.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-25 18:41:34 +02:00
Wolfram Sang
ce8cb803d8 i2c: mux: demux-pinctrl: properly roll back when adding adapter fails
We also need to revert the dynamic OF change, so we get a consistent
state again. Otherwise, we might have two devices enabled e.g. after
pinctrl setup fails.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-08-15 00:55:07 +02:00
Lukasz Gemborowski
22ebf00eb5 i2c: mux: reg: wrong condition checked for of_address_to_resource return value
of_address_to_resource return 0 on successful call but
devm_ioremap_resource is called only if it returns non-zero value

Signed-off-by: Lukasz Gemborowski <lukasz.gemborowski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-07-06 00:33:49 +09:00
Lukasz Gemborowski
9f05e62190 i2c: mux: reg: Provide of_match_table
of_match_table was not filled which prevents device to be
instantiated from device tree node.

Signed-off-by: Lukasz Gemborowski <lukasz.gemborowski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-09 22:38:16 +02:00
Peter Rosin
6ef91fcca8 i2c: mux: relax locking of the top i2c adapter during mux-locked muxing
With a i2c topology like the following

                       GPIO ---|  ------ BAT1
                        |      v /
   I2C  -----+----------+---- MUX
             |                   \
           EEPROM                 ------ BAT2

there is a locking problem with the GPIO controller since it is a client
on the same i2c bus that it muxes. Transfers to the mux clients (e.g. BAT1)
will lock the whole i2c bus prior to attempting to switch the mux to the
correct i2c segment. In the above case, the GPIO device is an I/O expander
with an i2c interface, and since the GPIO subsystem knows nothing (and
rightfully so) about the lockless needs of the i2c mux code, this results
in a deadlock when the GPIO driver issues i2c transfers to modify the
mux.

So, observing that while it is needed to have the i2c bus locked during the
actual MUX update in order to avoid random garbage on the slave side, it
is not strictly a must to have it locked over the whole sequence of a full
select-transfer-deselect mux client operation. The mux itself needs to be
locked, so transfers to clients behind the mux are serialized, and the mux
needs to be stable during all i2c traffic (otherwise individual mux slave
segments might see garbage, or worse).

Introduce this new locking concept as "mux-locked" muxes, and call the
pre-existing mux locking scheme "parent-locked".

Modify the i2c mux locking so that muxes that are "mux-locked" locks only
the muxes on the parent adapter instead of the whole i2c bus when there is
a transfer to the slave side of the mux. This lock serializes transfers to
the slave side of the muxes on the parent adapter.

Add code to i2c-mux-gpio and i2c-mux-pinctrl that checks if all involved
gpio/pinctrl devices have a parent that is an i2c adapter in the same
adapter tree that is muxed, and request a "mux-locked mux" if that is the
case.

Modify the select-transfer-deselect code for "mux-locked" muxes so
that each of the select-transfer-deselect ops locks the mux parent
adapter individually.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-04 22:39:17 +02:00
Wolfram Sang
2c89e5d884 i2c: mux: pinctrl: fix indentation for better readability
smatch rightfully says:

drivers/i2c/muxes/i2c-mux-pinctrl.c:175 i2c_mux_pinctrl_probe() warn: inconsistent indenting

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-24 23:11:41 +02:00
Peter Rosin
193304aef8 i2c: i2c-mux-reg: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:41 +02:00
Peter Rosin
7fcac98071 i2c: i2c-mux-pca954x: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Add a mask to handle the case where not all child adapters should
cause a mux deselect to happen, now that there is a common deselect op
for all child adapters.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:40 +02:00
Peter Rosin
ab88b97c69 i2c: i2c-mux-pca9541: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:39 +02:00
Peter Rosin
8aacd90166 i2c: i2c-arb-gpio-challenge: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:38 +02:00
Peter Rosin
4bbe7fb0a2 i2c: i2c-mux-pinctrl: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:37 +02:00
Peter Rosin
bb44814763 i2c: i2c-mux-gpio: convert to use an explicit i2c mux core
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22 14:56:36 +02:00
Ben Hutchings
c0c508a418 i2c: mux: demux-pinctrl: Clean up sysfs attributes
sysfs attributes should use the same format for reads and writes,
rather than pretty-printing on read.

* Make the "cur_master" attribute read back as just the name of the
  master
* Expose the list of all masters as a read-only "available_masters"
  attribute, using space separators as in similar attributes of other
  devices

Also, spell out "cur_master" in full as "current_master".

Fixes: 50a5ba8769 ("i2c: mux: demux-pinctrl: add driver")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-01 13:00:07 +02:00
Wolfram Sang
50a5ba8769 i2c: mux: demux-pinctrl: add driver
This driver allows an I2C bus to switch between multiple masters. This
is not hot-switching because connected I2C slaves will be
re-instantiated. It is meant to select the best I2C core at runtime once
the task is known. Example: Prefer i2c-gpio over another I2C core
because of HW errata affecting your use case.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-02-12 19:16:04 +01:00
York Sun
5a73882fd2 i2c: mux: reg Change ioread endianness for readback
Reading the register (if allowed) after writing is to ensure writing
is completed on a posted bus. The endianness of reading doesn't matter.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-09-03 11:58:42 +02:00
Mike Rapoport
a05a34e7f6 i2c: mux: reg: fix compilation warnings
With CONFIG_OF=n, the following warnings occur when compiling
drivers/i2c/muxes/i2c-mux-reg.c:

  CC      drivers/i2c/muxes/i2c-mux-reg.o
drivers/i2c/muxes/i2c-mux-reg.c:170:13: warning: ‘struct gpiomux’ declared inside parameter list [enabled by default]
      struct platform_device *pdev)
             ^
drivers/i2c/muxes/i2c-mux-reg.c:170:13: warning: its scope
is only this definition or declaration, which is probably not what you want [enabled by default]
drivers/i2c/muxes/i2c-mux-reg.c: In function ‘i2c_mux_reg_probe’:
drivers/i2c/muxes/i2c-mux-reg.c:201:3: warning: passing argument 1 of ‘i2c_mux_reg_probe_dt’ from incompatible pointer type [enabled by default]
   ret = i2c_mux_reg_probe_dt(mux, pdev);
   ^

Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-09-03 11:56:23 +02:00
Wolfram Sang
fce388afd6 i2c: mux: reg: simplify register size checking
Checking was done at three different locations, just do it once and
properly at probing time.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: York Sun <yorksun@freescale.com>
2015-09-03 11:54:41 +02:00
Vladimir Zapolskiy
bdbf4a29ee i2c: muxes: fix leaked i2c adapter device node references
Every call of of_parse_phandle() increments user count of found device
node, if OF_DYNAMIC is enabled.

The change fixes all similar addressed cases in drivers/i2c.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-31 22:40:34 +02:00
York Sun
b3fdd32799 i2c: mux: Add register-based mux i2c-mux-reg
Based on i2c-mux-gpio driver, similarly the register-based mux
switch from one bus to another by setting a single register.
The register can be on PCIe bus, local bus, or any memory-mapped
address. The endianness of such register can be specified in device
tree if used, or in platform data.

Signed-off-by: York Sun <yorksun@freescale.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-24 14:05:18 +02:00
Vladimir Zapolskiy
0d1ad98dd8 i2c: arb-gpio-challenge: use of_get_i2c_adapter_by_node interface
This change is needed to properly lock I2C parent bus driver.

Prior to this change i2c_put_adapter() is misused, which may lead
to an overflow over zero of I2C bus driver user counter.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10 08:37:36 +02:00
Krzysztof Kozlowski
069d5b745b i2c: Drop owner assignment from i2c_driver
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10 08:37:35 +02:00
Alexander Sverdlin
0a8237ae31 i2c: mux: pca954x: Use __i2c_transfer because of quirks
pca9541 and pca954x are calling master_xfer() of the parent adapter directly
thus bypassing the quirks checks of the adapter. Use __i2c_transfer() instead.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Fixes: b7f6258402 ("i2c: add quirk checks to core")
2015-06-17 14:35:38 +02:00
Geert Uytterhoeven
7e5cd69a91 i2c: Allow compile test of GPIO consumers if !GPIOLIB
The GPIO subsystem provides dummy GPIO consumer functions if GPIOLIB is
not enabled. Hence drivers that depend on GPIOLIB, but use GPIO consumer
functionality only, can still be compiled if GPIOLIB is not enabled.

Relax the dependency on GPIOLIB if COMPILE_TEST is enabled, where
appropriate.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-05-12 15:22:52 +02:00
Ioan Nicu
623e4ecb86 i2c: i2c-mux-gpio: remove error messages for probe deferrals
Probe deferral is not an error case. It happens only when
the necessary dependencies are not there yet.

The driver core is already printing a message when a driver
requests probe deferral, so this can be traced in the logs
without these error prints.

This patch removes the error messages for these deferral cases.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@nokia.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-04-03 22:00:14 +02:00
Uwe Kleine-König
58b59e0f24 i2c: pca954x: improve usage of gpiod API
Since 39b2bbe3d7 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for
outputs.

Also there is an *_optional variant that serves well here.  The sematics
is slightly changed here by using it. Now if a reset gpio is specified
and getting hold on it fails, pca954x_probe fails, too.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:59 +01:00
Alexander Sverdlin
72f0271576 of: i2c: Add i2c-mux-idle-disconnect DT property to PCA954x mux driver
Add i2c-mux-idle-disconnect device tree property to PCA954x mux driver. The new
property forces the multiplexer to disconnect child buses in idle state. This is
used, for example, when there are several multiplexers on the same bus and the
devices on the underlying buses might have same I2C addresses.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
[wsa: added a newline]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-23 17:12:56 +01:00
Wolfram Sang
37e5dc1c27 i2c: muxes: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:38 +02:00
Linus Torvalds
f7dbaef505 Merge branch 'i2c/for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Highlights:

   - class based instantiation finally dropped for most embedded drivers
     bringing boot up performance gains
   - removed two drivers (one outdated, one a duplicate)
   - ACPI has now operation region support (thanks to Lan Tianyu)
   - the i2c-stub driver got overhauled and gained new features to
     become more useful when writing i2c client drivers (thanks to
     Guenter Roeck and Jean Delvare)

  The rest is driver bugfixes, added bindings/ids, cleanups..."

* 'i2c/for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (43 commits)
  i2c: mpc: delete unneeded test before of_node_put
  i2c: rk3x: fix interrupt handling issue
  i2c: imx: Fix format warning for dev_dbg
  i2c: qup: disable clks and return instead of just returning error
  i2c: exynos5: always enable HSI2C
  i2c: designware: add new bindings
  i2c: gpio: Drop dead code in i2c_gpio_remove
  i2c: pca954x: put the mux to disconnected state after resume
  i2c: st: Update i2c timings
  drivers/i2c/busses: use correct type for dma_map/unmap
  i2c: i2c-st: Use %pa to print 'resource_size_t' type
  i2c: s3c2410: resume the I2C controller earlier
  i2c: stub: Avoid an array overrun on I2C block transfers
  i2c: i801: Add device ID for Intel Wildcat Point PCH
  i2c: i801: Fix the alignment of the device table
  i2c: stub: Add support for banked register ranges
  i2c: stub: Remember the number of emulated chips
  i2c: stub: Add support for SMBus block commands
  i2c: efm32: correct namespacing of location property
  i2c: exynos5: remove extra line and fix an assignment
  ...
2014-08-09 09:15:07 -07:00
Jisheng Zhang
f5e596cd9f i2c: pca954x: put the mux to disconnected state after resume
pca954x may be power lost during suspend, so after resume we also suffer
the issue fixed by commit cd823db8b1,

 "pca954x power-on default is channel 0 connected. If multiple pca954x
 muxes are connected to the same physical I2C bus, the parent bus will
 see channel 0 devices behind both muxes by default."

What's more, when resume bootloader may also operate the mux, so the
the channel connected after that may not be the one driver thought.

We fix this problem by putting the mux to disconnected state and
clearing last_chan in the resume hook.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-01 19:54:59 +02:00
Linus Walleij
e556756a63 i2c: mux: pca954x: fix dependencies
This driver causes the following randconfig build error:

drivers/i2c/muxes/i2c-mux-pca954x.c: In function ‘pca954x_probe’:
drivers/i2c/muxes/i2c-mux-pca954x.c:204:2: error: implicit declaration
of function ‘devm_gpiod_get’ [-Werror=implicit-function-declaration]
  gpio = devm_gpiod_get(&client->dev, "reset");
  ^
drivers/i2c/muxes/i2c-mux-pca954x.c:204:7: warning: assignment makes
pointer from integer without a cast [enabled by default]
  gpio = devm_gpiod_get(&client->dev, "reset");
       ^
drivers/i2c/muxes/i2c-mux-pca954x.c:206:3: error: implicit declaration
of function ‘gpiod_direction_output’
[-Werror=implicit-function-declaration]
   gpiod_direction_output(gpio, 0);
   ^
cc1: some warnings being treated as errors
make[3]: *** [drivers/i2c/muxes/i2c-mux-pca954x.o] Error 1

This is because it is getting compiled without gpiolib, so
introduce an explicit dependency.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-27 14:27:19 +02:00
Laurent Pinchart
642653d16a i2c: pca954x: Fix compilation without CONFIG_GPIOLIB
The pca954x driver recently switched to the GPIO descriptor API without
including the correct <linux/gpio/consumer.h> header. This breaks
compilation without CONFIG_GPIOLIB.

drivers/i2c/muxes/i2c-mux-pca954x.c: In function ‘pca954x_probe’:
drivers/i2c/muxes/i2c-mux-pca954x.c:204:2: error: implicit declaration
of function ‘devm_gpiod_get’ [-Werror=implicit-function-declaration]
  gpio = devm_gpiod_get(&client->dev, "reset");
  ^
drivers/i2c/muxes/i2c-mux-pca954x.c:204:7: warning: assignment makes
pointer from integer without a cast [enabled by default]
  gpio = devm_gpiod_get(&client->dev, "reset");
       ^
drivers/i2c/muxes/i2c-mux-pca954x.c:206:3: error: implicit declaration
of function ‘gpiod_direction_output’
[-Werror=implicit-function-declaration]
   gpiod_direction_output(gpio, 0);
   ^
cc1: some warnings being treated as errors
make[3]: *** [drivers/i2c/muxes/i2c-mux-pca954x.o] Error 1

Fix it by including the right header.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-05 15:09:33 +02:00
Laurent Pinchart
4807e8459b i2c: mux: pca954x: Use the descriptor-based GPIO API
The ID-based GPIO API pushes handling of GPIO polarity to drivers.
Simplify the driver by switching to the descriptor-based GPIO API.

This also fixes a mismatch between the pca954x DT bindings that document
a "reset-gpios" property and the driver that requests a "reset-gpio"
property.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-03 14:24:20 +02:00
Linus Torvalds
f7a6ad9fa2 Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull more i2c updates from Wolfram Sang:
 "Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
  applied"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rcar: fix NACK error code
  i2c: update i2c_algorithm documentation
  i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
  i2c: rcar: do not print error if device nacks transfer
  i2c: rely on driver core when sanitizing devices
  i2c: delete non-required instances of include <linux/init.h>
  i2c: acorn: is tristate and should use module.h
  i2c: piix4: Standardize log messages
  i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
  i2c: piix4: Add support for AMD ML and CZ SMBus changes
2014-01-29 19:56:20 -08:00
Linus Torvalds
9076e0cae7 Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull hwmon updates from Jean Delvare:
 "This include it87 driver improvements, and a tree-wide change of my
  e-mail address"

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  Update Jean Delvare's e-mail address
  hwmon: (it87) Print proper names for the IT8771E and IT8772E
  hwmon: (it87) Add support for the ITE IT8603E
2014-01-29 18:56:27 -08:00
Jean Delvare
7c81c60f37 Update Jean Delvare's e-mail address
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2014-01-29 20:40:08 +01:00
Paul Gortmaker
21d0b7c0fa i2c: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-24 18:24:31 +01:00
Laurent Pinchart
12097957a9 i2c: pca954x: Add reset GPIO support
If a reset GPIO support is specified, request the GPIO and get the chip
out of reset at probe time.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-03 17:40:27 +01:00
Laurent Pinchart
bc12cfc87f i2c: pca954x: Use devm_kzalloc managed allocator
This simplifies error and removal paths.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-03 17:40:20 +01:00
Laurent Pinchart
4b9b00734b i2c: pca954x: Sort headers alphabetically
This helps avoiding duplicate includes.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-03 16:40:55 +01:00
Linus Torvalds
13509c3a9d Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c changes from Wolfram Sang:
 - new drivers for exynos5, bcm kona, and st micro
 - bigger overhauls for drivers mxs and rcar
 - typical driver bugfixes, cleanups, improvements
 - got rid of the superfluous 'driver' member in i2c_client struct This
   touches a few drivers in other subsystems.  All acked.

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits)
  i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe()
  i2c: i2c-eg20t: do not print error message in syslog if no ACK received
  i2c: bcm-kona: Introduce Broadcom I2C Driver
  i2c: cbus-gpio: Fix device tree binding
  i2c: wmt: add missing clk_disable_unprepare() on error
  i2c: designware: add new ACPI IDs
  i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH
  i2c: exynos5: Remove incorrect clk_disable_unprepare
  i2c: i2c-st: Add ST I2C controller
  i2c: exynos5: add High Speed I2C controller driver
  i2c: rcar: fixup rcar type naming
  i2c: scmi: remove some bogus NULL checks
  i2c: sh_mobile & rcar: Enable the driver on all ARM platforms
  i2c: sh_mobile: Convert to clk_prepare/unprepare
  i2c: mux: gpio: use reg value for i2c_add_mux_adapter
  i2c: mux: gpio: use gpio_set_value_cansleep()
  i2c: Include linux/of.h header
  i2c: mxs: Fix PIO mode on i.MX23
  i2c: mxs: Rework the PIO mode operation
  i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller
  ...
2013-11-18 15:50:07 -08:00
Ionut Nicu
8c0ec2500e i2c: mux: gpio: use reg value for i2c_add_mux_adapter
The i2c-mux driver requires that the chan_id parameter
passed to the i2c_add_mux_adapter() function is equal
to the reg value for that adapter:

for_each_child_of_node(mux_dev->of_node, child) {
	ret = of_property_read_u32(child, "reg", &reg);
	if (ret)
		continue;
	if (chan_id == reg) {
		priv->adap.dev.of_node = child;
		break;
	}
}

The i2c-mux-gpio driver uses an internal logical index
for chan_id when calling i2c_add_mux_adapter() instead
of using the reg value.

Because of this, there will problems in selecting the
right adapter when the i2c-mux-gpio's index into
mux->data.values doesn't match the reg value.

An example of such a case:

mux->data.values = { 1, 0 }

For chan_id = 0, i2c-mux will bind the adapter to the
of_node with reg = <0>, but when it will call the
select() callback with chan_id set to 0, the i2c-mux-gpio
will use it as an index into mux->data.values and it will
actually select the bus with reg = <1>.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2013-10-30 17:29:46 +01:00
Ionut Nicu
250ad590d6 i2c: mux: gpio: use gpio_set_value_cansleep()
Some gpio chips may have get/set operations that
can sleep. gpio_set_value() only works for chips
which do not sleep, for the others we will get a
kernel warning. Using gpio_set_value_cansleep()
will work for both chips that do sleep and those
who don't.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2013-10-30 17:29:40 +01:00
Sachin Kamat
4edd65e63f i2c: Include linux/of.h header
'of_match_ptr' is defined in linux/of.h. Include it explicitly to
avoid build breakage in the future.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-30 16:46:30 +01:00
Wolfram Sang
2737de460e i2c: i2c-mux-pinctrl: use deferred probe when adapter not found
If it is not there yet, it might appear later.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:35 +02:00
Wolfram Sang
0cd98069ad i2c: i2c-arb-gpio-challenge: use deferred probe when adapter not found
If it is not there yet, it might appear later.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:34 +02:00
Ionut Nicu
9937b8d89e i2c: i2c-mux-gpio: use deferred probing
If the i2c-parent bus driver is not loaded, returning
-ENODEV will force people to unload and then reload the
module again to get it working.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:33 +02:00
Ionut Nicu
492ed77bfa i2c: i2c-mux-gpio: don't ignore of_get_named_gpio errors
of_get_named_gpio could return -E_PROBE_DEFER or another
error code. This error should be passed further instead
of being ignored.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@nsn.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:32 +02:00
Sachin Kamat
4e9053231a i2c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-03 22:00:41 +02:00
Wolfram Sang
687b81d083 i2c: move OF helpers into the core
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: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:20 +02:00
Jingoo Han
6d4028c644 i2c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-19 19:46:30 +02:00
Linus Torvalds
5647ac0ad4 Removal of GENERIC_GPIO for v3.10
GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any valid
 cases for enableing GENERIC_GPIO without GPIOLIB, even though it is
 possible to do so which has been causing confusion and breakage. This
 branch does the work to completely eliminate GENERIC_GPIO.
 
 However, it is not trivial to just create a branch to remove it. Over
 the course of the v3.9 cycle more code referencing GENERIC_GPIO has been
 added to linux-next that conflicts with this branch. The following must
 be done to resolve the conflicts when merging this branch into mainline:
 
 * "git grep CONFIG_GENERIC_GPIO" should return 0 hits. Matches should be
   replaced with CONFIG_GPIOLIB
 * "git grep '\bGENERIC_GPIO\b'" should return 1 hit in the Chinese
   documentation.
 * Selectors of GENERIC_GPIO should be turned into selectors of GPIOLIB
 * definitions of the option in architecture Kconfig code should be deleted.
 
 Stephen has 3 merge fixup patches[1] that do the above. They are currently
 applicable on mainline as of May 2nd.
 
 [1] http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg428056.html
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux

Pull removal of GENERIC_GPIO from Grant Likely:
 "GENERIC_GPIO now synonymous with GPIOLIB.  There are no longer any
  valid cases for enableing GENERIC_GPIO without GPIOLIB, even though it
  is possible to do so which has been causing confusion and breakage.
  This branch does the work to completely eliminate GENERIC_GPIO."

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux:
  gpio: update gpio Chinese documentation
  Remove GENERIC_GPIO config option
  Convert selectors of GENERIC_GPIO to GPIOLIB
  blackfin: force use of gpiolib
  m68k: coldfire: use gpiolib
  mips: pnx833x: remove requirement for GENERIC_GPIO
  openrisc: default GENERIC_GPIO to false
  avr32: default GENERIC_GPIO to false
  xtensa: remove explicit selection of GENERIC_GPIO
  sh: replace CONFIG_GENERIC_GPIO by CONFIG_GPIOLIB
  powerpc: remove redundant GENERIC_GPIO selection
  unicore32: default GENERIC_GPIO to false
  unicore32: remove unneeded select GENERIC_GPIO
  arm: plat-orion: use GPIO driver on CONFIG_GPIOLIB
  arm: remove redundant GENERIC_GPIO selection
  mips: alchemy: require gpiolib
  mips: txx9: change GENERIC_GPIO to GPIOLIB
  mips: loongson: use GPIO driver on CONFIG_GPIOLIB
  mips: remove redundant GENERIC_GPIO select
2013-05-09 09:59:16 -07:00
Doug Anderson
b81dfaa01f i2c: mux: Add i2c-arb-gpio-challenge 'mux' driver
The i2c-arb-gpio-challenge driver implements an I2C arbitration scheme
where masters need to claim the bus with a GPIO before they can start
a transaction.  This should generally only be used when standard I2C
multimaster isn't appropriate for some reason (errata/bugs).

This driver is based on code that Simon Glass added to the i2c-s3c2410
driver in the Chrome OS kernel 3.4 tree.  The current incarnation as a
mux driver is as suggested by Grant Likely.  See
<https://patchwork.kernel.org/patch/1877311/> for some history.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-17 11:31:03 +02:00
Alexandre Courbot
76ec9d18b8 Convert selectors of GENERIC_GPIO to GPIOLIB
GENERIC_GPIO is now equivalent to GPIOLIB and features that depended on
GENERIC_GPIO can now depend on GPIOLIB to allow removal of this option.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2013-04-16 18:47:14 +09:00
Lars-Peter Clausen
a205e63d12 i2c: Ignore the return value of i2c_del_mux_adapter()
i2c_del_mux_adapter() always returns 0. So all checks testing whether it will be
non zero will always evaluate to false and the conditional code is dead code.
This patch updates all callers of i2c_del_mux_adapter() to ignore its return
value and assume that it will always succeed (which it will). A subsequent
patch will make the return type of i2c_del_mux_adapter() void.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02 07:07:29 +02:00
Jean Delvare
7fafae669a i2c: mux: gpio: Check gpio_direction_output return value
gpio_direction_output() may fail, check for that and deal with it
appropriately. Also log an error message if gpio_request() fails.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-27 08:55:13 +01:00
Guenter Roeck
b104153e36 i2c: Fix my e-mail address in drivers and documentation
My old e-mail address is no longer working.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-22 11:18:34 +01:00
Linus Torvalds
52caa59ed3 Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Highlights:

   - new drivers for Intel ismt & Broadcom bcm2835
   - a number of drivers got support for more variants and mostly got
     cleaned up on the way (sis630, i801, at91, tegra, designware)
   - i2c got rid of all *_set_drvdata(..., NULL) on remove/probe failure
   - removed the i2c_smbus_process_call from the core since there are no
     users
   - mxs can now switch between PIO and DMA depending on the message
     size and the bus speed can now be arbitrary

  In addition, there is the usual bunch of fixes, cleanups, devm_*
  conversions, etc"

Fixed conflict (and buggy devm_* conversion) in i2c-s3c2410.c

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (39 commits)
  i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
  i2c: pxa: remove incorrect __exit annotations
  i2c: ocores: Fix pointer to integer cast warning
  i2c: tegra: remove warning dump if timeout happen in transfer
  i2c: fix i2c-ismt.c printk format warning
  i2c: i801: Add Device IDs for Intel Wellsburg PCH
  i2c: add bcm2835 driver
  i2c: ismt: Add Seth and Myself as maintainers
  i2c: sis630: checkpatch cleanup
  i2c: sis630: display unsigned hex
  i2c: sis630: use hex to constants for SMBus commands
  i2c: sis630: fix behavior after collision
  i2c: sis630: clear sticky bits
  i2c: sis630: Add SIS964 support
  i2c: isch: Add module parameter for backbone clock rate if divider is unset
  i2c: at91: fix unsed variable warning when building with !CONFIG_OF
  i2c: Adding support for Intel iSMT SMBus 2.0 host controller
  i2c: sh_mobile: don't send a stop condition by default inside transfers
  i2c: sh_mobile: eliminate an open-coded "goto" loop
  i2c: sh_mobile: fix timeout error handling
  ...
2013-02-26 09:41:53 -08:00
Doug Anderson
55827f4aa6 i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
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: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2013-02-22 00:25:50 +01:00
Greg Kroah-Hartman
422d26b6ec Merge 3.8-rc5 into driver-core-next
This resolves a gpio driver merge issue pointed out in linux-next.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-25 21:06:30 -08:00
Laurent Navet
43a2bd42d0 i2c: muxes: fix wrong use of sizeof(ptr)
sizeof when applied to a pointer typed expression gives the size of
the pointer

The semantic patch that makes this output is available
in scripts/coccinelle/misc/noderef.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/

Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-01-22 09:54:32 +01:00
Kees Cook
240335fd04 drivers/i2c/muxes: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Stephen Warren <swarren@nvidia.com>
CC: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
2013-01-11 11:38:05 -08:00
Bill Pemberton
0b255e927d i2c: remove __dev* attributes from subsystem
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: Bill 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: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-12-22 20:13:45 +01:00
Linus Torvalds
752451f01c Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull i2c-embedded changes from Wolfram Sang:
 - CBUS driver (an I2C variant)
 - continued rework of the omap driver
 - s3c2410 gets lots of fixes and gains pinctrl support
 - at91 gains DMA support
 - the GPIO muxer gains devicetree probing
 - typical fixes and additions all over

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (45 commits)
  i2c: omap: Remove the OMAP_I2C_FLAG_RESET_REGS_POSTIDLE flag
  i2c: at91: add dma support
  i2c: at91: change struct members indentation
  i2c: at91: fix compilation warning
  i2c: mxs: Do not disable the I2C SMBus quick mode
  i2c: mxs: Handle i2c DMA failure properly
  i2c: s3c2410: Remove recently introduced performance overheads
  i2c: ocores: Move grlib set/get functions into #ifdef CONFIG_OF block
  i2c: s3c2410: Add fix for i2c suspend/resume
  i2c: s3c2410: Fix code to free gpios
  i2c: i2c-cbus-gpio: introduce driver
  i2c: ocores: Add support for the GRLIB port of the controller and use function pointers for getreg and setreg functions
  i2c: ocores: Add irq support for sparc
  i2c: omap: Move the remove constraint
  ARM: dts: cfa10049: Add the i2c muxer buses to the CFA-10049
  i2c: s3c2410: do not special case HDMIPHY stuck bus detection
  i2c: s3c2410: use exponential back off while polling for bus idle
  i2c: s3c2410: do not generate STOP for QUIRK_HDMIPHY
  i2c: s3c2410: grab adapter lock while changing i2c clock
  i2c: s3c2410: Add support for pinctrl
  ...
2012-12-18 16:51:10 -08:00
Maxime Ripard
9b7a0c40de i2c: mux: Add dt support to i2c-mux-gpio driver
Allow the i2c-mux-gpio to be used by a device tree enabled device. The
bindings are inspired by the one found in the i2c-mux-pinctrl driver.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>

[wsa: fixed some whitespace]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-16 09:28:27 +01:00
Guenter Roeck
aa1e3e81e7 i2c-mux-pinctrl: Fix probe error path
When allocating the memory for i2c busses, the code checked the wrong
variable and thus never detected if there was a memory error.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-11-13 22:27:19 +01:00
Jean Delvare
e7ee514058 i2c-mux-gpio: Add support for dynamically allocated GPIO pins
The code instantiating an i2c-mux-gpio platform device doesn't
necessarily know in advance the GPIO pin numbers it wants to use. If
pins are on a GPIO device which gets its base GPIO number assigned
dynamically at run-time, the values can't be hard-coded.

In that case, let the caller tell i2c-mux-gpio the name of the GPIO
chip and the (relative) GPIO pin numbers to use. At probe time, the
i2c-mux-gpio driver will look for the chip and apply the proper offset
to turn relative GPIO pin numbers to absolute GPIO pin numbers.

The same could be (and was so far) done on the caller's end, however
doing it in i2c-mux-gpio has two benefits:
* It avoids duplicating the code on every caller's side (about 30
  lines of code.)
* It allows for deferred probing for the muxed part of the I2C bus
  only. If finding the GPIO chip is the caller's responsibility, then
  deferred probing (if the GPIO chip isn't there yet) will not only
  affect the mux and the I2C bus segments behind it, but also the I2C
  bus trunk.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
2012-10-05 22:23:54 +02:00
Maxime Ripard
2614a85941 i2c-mux-gpio: Use devm_kzalloc instead of kzalloc
Use the devm_kzalloc managed function to stripdown the error and remove
code.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05 22:23:53 +02:00
Jean Delvare
eee543e824 i2c-mux: Add support for device auto-detection
Let I2C bus segments behind multiplexers have a class. This allows for
device auto-detection on these segments. As long as parent segments
don't share the same class, it should be fine.

I implemented support in drivers i2c-mux-gpio and i2c-mux-pca954x. I
left i2c-mux-pca9541 and i2c-mux-pinctrl alone for the moment as I
don't know if this feature makes sense for the use cases of these
drivers.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Rodolfo Giometti <giometti@linux.it>
2012-10-05 22:23:51 +02:00
Guenter Roeck
83a638df36 i2c: Update Guenter Roeck's e-mail address
My old e-mail address won't be valid for much longer. Time to update it.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:56 +02:00
Stephen Warren
ae58d1e406 i2c: Add generic I2C multiplexer using pinctrl API
This is useful for SoCs whose I2C module's signals can be routed to
different sets of pins at run-time, using the pinctrl API.

                                 +-----+  +-----+
                                 | dev |  | dev |
    +------------------------+   +-----+  +-----+
    | SoC                    |      |        |
    |                   /----|------+--------+
    |   +---+   +------+     | child bus A, on first set of pins
    |   |I2C|---|Pinmux|     |
    |   +---+   +------+     | child bus B, on second set of pins
    |                   \----|------+--------+--------+
    |                        |      |        |        |
    +------------------------+  +-----+  +-----+  +-----+
                                | dev |  | dev |  | dev |
                                +-----+  +-----+  +-----+

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-06-04 16:49:43 +02:00
Jean Delvare
e7065e20d9 i2c: Rename last mux driver to standard pattern
Update the MAINTAINERS entry and all other references accordingly.

Based on an original patch by Wolfram Sang.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>

[wsa: fixed merge conflict due to rework in i2c_add_mux_adapter()]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-12 14:28:18 +02:00
Wolfram Sang
b4f0b74ea3 i2c: muxes: rename first set of drivers to a standard pattern
Apply a naming pattern like in the rest of the subsystem to a first set
of mux drivers. Those drivers are the low-hanging fruit; we want to pick
them to motivate upcoming drivers to follow the new pattern. The missing
GPIO driver will be converted in a later patch.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (pca9541)
Acked-by: Jean Delvare <khali@linux-fr.org>
2012-05-12 14:28:17 +02:00
David Daney
5a3ecd5f98 i2c: Add a struct device * parameter to i2c_add_mux_adapter()
And adjust all callers.

The new device parameter is used in the next patch to initialize the
mux's of_node so that its children may be automatically populated.

Signed-off-by: David Daney <david.daney@cavium.com>
Tested-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-12 14:28:15 +02:00
Axel Lin
de05497aab i2c: Convert drivers/i2c/muxes/* to use module_i2c_driver()
This patch converts the drivers in drivers/i2c/muxes/* to use the
module_i2c_driver() macro which makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-03-26 21:47:19 +02:00
Axel Lin
245e99cfe8 i2c/gpio-i2cmux: Convert to use module_platform_driver()
Convert gpio-i2cmux to use the module_platform_driver() macro which
makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-01-12 20:32:04 +01:00
Petri Gynther
cd823db8b1 i2c/pca954x: Initialize the mux to disconnected state
pca954x power-on default is channel 0 connected. If multiple pca954x
muxes are connected to the same physical I2C bus, the parent bus will
see channel 0 devices behind both muxes by default. This is bad.

Scenario:
            -- pca954x @ 0x70 -- ch 0 (I2C-bus-101) -- EEPROM @ 0x50
            |
I2C-bus-1 ---
            |
            -- pca954x @ 0x71 -- ch 0 (I2C-bus-111) -- EEPROM @ 0x50

1. Load I2C bus driver: creates I2C-bus-1
2. Load pca954x driver: creates virtual I2C-bus-101 and I2C-bus-111
3. Load eeprom driver
4. Try to read EEPROM @ 0x50 on I2C-bus-101. The transaction will also bleed
   onto I2C-bus-111 because pca954x @ 0x71 channel 0 is connected by default.

Fix: Initialize pca954x to disconnected state in pca954x_probe()

Signed-off-by: Petri Gynther <pgynther@google.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org
2011-06-29 11:36:11 +02:00
Peter Korsgaard
92ed1a76ca i2c: Add generic I2C multiplexer using GPIO API
Add an i2c mux driver providing access to i2c bus segments using a
hardware MUX sitting on a master bus and controlled through gpio pins.

E.G. something like:

  ----------              ----------  Bus segment 1   - - - - -
 |          | SCL/SDA    |          |-------------- |           |
 |          |------------|          |
 |          |            |          | Bus segment 2 |           |
 |  Linux   | GPIO 1..N  |   MUX    |---------------   Devices
 |          |------------|          |               |           |
 |          |            |          | Bus segment M
 |          |            |          |---------------|           |
  ----------              ----------                  - - - - -

SCL/SDA of the master I2C bus is multiplexed to bus segment 1..M
according to the settings of the GPIO pins 1..N.

Signed-off-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-01-10 22:11:23 +01:00
Guenter Roeck
db79f2a1d2 i2c/pca954x: Remove __devinit and __devexit from probe and remove functions
The underlying I2C adapter may or may not be present when this driver
gets initialized, and may disappear later, so there is no safe time at
which the probe and remove functions can be discarded.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-10-24 18:16:59 +02:00
Guenter Roeck
ae63b13bbe i2c/mux: Driver for PCA9541 I2C Master Selector
This patch adds support for PCA9541, an I2C Bus Master Selector.
The driver is modeled as single channel I2C Multiplexer to be able to utilize
the I2C multiplexer framework.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Tom Grennan <tom.grennan@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
2010-10-24 18:16:58 +02:00
matt mooney
ef9d9b8fb6 i2c: Change to new flag variable
Replace EXTRA_CFLAGS with ccflags-y.

Signed-off-by: matt mooney <mfm@muteddisk.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-10-24 18:16:58 +02:00
Michael Lawnick
7f528135da i2c: I2C bus multiplexer driver pca954x
I2C driver for PCA954x I2C multiplexer series.

Signed-off-by: Michael Lawnick <ml.lawnick@gmx.de>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-08-11 18:21:03 +02:00