Commit graph

13 commits

Author SHA1 Message Date
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