Commit graph

4 commits

Author SHA1 Message Date
Andy Shevchenko
79dd67306f platform/x86: i2c-multi-instantiate: Get rid of obsolete conditional
Now, when i2c_acpi_new_device() never returns NULL, there is no point to check
for it. Besides that, i2c_acpi_new_device() returns -EPROBE_DEFER directly and
caller doesn't need to guess is better.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
2018-12-03 21:40:02 +02:00
Andy Shevchenko
1aaeae493a platform/x86: i2c-multi-instantiate: Defer probe when no adapter found
Likewise the rest of the i2c_acpi_new_device() users, defer the probe
of the i2c-multi-intantiate driver in case adapter is not yet found.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
2018-12-03 21:40:02 +02:00
Andy Shevchenko
41daf98582 platform/x86: i2c-multi-instantiate: Accept errors of i2c_acpi_new_device()
In the future i2c_acpi_new_device() will return error pointer in some cases.
Prepare i2c-multi-instantiate driver to support that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
2018-12-03 21:40:01 +02:00
Hans de Goede
e64e84987d platform/x86: Add ACPI i2c-multi-instantiate pseudo driver
On systems with ACPI instantiated i2c-clients, normally there is 1 fw_node
per i2c-device and that fw-node contains 1 I2cSerialBus resource for that 1
i2c-device.

But in some rare cases the manufacturer has decided to describe multiple
i2c-devices in a single ACPI fwnode with multiple I2cSerialBus resources.

An earlier attempt to fix this in the i2c-core resulted in a lot of extra
code to support this corner-case.

This commit introduces a new i2c-multi-instantiate driver which fixes this
in a different way. This new driver can be built as a module which will
only loaded on affected systems.

This driver will instantiate a new i2c-client per I2cSerialBus resource,
using the driver_data from the acpi_device_id it is binding to to tell it
which chip-type (and optional irq-resource) to use when instantiating.

Note this driver depends on a platform device being instantiated for the
ACPI fwnode, see the i2c_multi_instantiate_ids list of ACPI device-ids in
drivers/acpi/scan.c: acpi_device_enumeration_by_parent().

Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-09 13:58:21 +02:00