linux/drivers/platform
Hans de Goede 97c2259ec7 platform/x86: int3472: Deal with probe ordering issues
The clk and regulator frameworks expect clk/regulator consumer-devices
to have info about the consumed clks/regulators described in the device's
fw_node.

To work around this info missing from the ACPI tables on devices where
the int3472 driver is used, the int3472 MFD-cell drivers attach info about
consumers to the clks/regulators when registering these.

This causes problems with the probe ordering wrt drivers for consumers
of these clks/regulators. Since the lookups are only registered when the
provider-driver binds, trying to get these clks/regulators before then
results in a -ENOENT error for clks and a dummy regulator for regulators.

All the sensor ACPI fw-nodes have a _DEP dependency on the INT3472 ACPI
fw-node, so to work around these probe ordering issues the ACPI core /
i2c-code does not instantiate the I2C-clients for any ACPI devices
which have a _DEP dependency on an INT3472 ACPI device until all
_DEP-s are met.

This relies on acpi_dev_clear_dependencies() getting called by the driver
for the _DEP-s when they are ready, add a acpi_dev_clear_dependencies()
call to the discrete.c probe code.

In the tps68470 case calling acpi_dev_clear_dependencies() is already done
by the acpi_gpiochip_add() call done by the driver for the GPIO MFD cell
(The GPIO cell is deliberately the last cell created to make sure the
clk + regulator cells are already instantiated when this happens).

However for proper probe ordering, the clk/regulator cells must not just
be instantiated the must be fully ready (the clks + regulators must be
registered with their subsystems).

Add MODULE_SOFTDEP dependencies for the clk and regulator drivers for
the instantiated MFD-cells so that these are loaded before us and so
that they bind immediately when the platform-devs are instantiated.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211203102857.44539-12-hdegoede@redhat.com
2021-12-13 11:44:51 +01:00
..
chrome platform/chrome: cros_ec_proto: Use ec_command for check_features 2021-10-31 15:52:55 -07:00
goldfish platform/goldfish: Convert pipe tasklet to threaded irq 2021-01-27 14:57:06 +01:00
mellanox platform/mellanox: mlxreg-lc: Add initial support for Nvidia line card devices 2021-10-19 10:41:56 +02:00
mips MIPS: Loongson: Fix boot warning about hwmon_device_register() 2020-07-16 10:49:55 +02:00
olpc Platform: OLPC: Constify static struct regulator_ops 2021-02-08 16:59:21 +01:00
surface platform/surface: aggregator_registry: Add initial support for Surface Pro 8 2021-10-28 11:21:17 +02:00
x86 platform/x86: int3472: Deal with probe ordering issues 2021-12-13 11:44:51 +01:00
Kconfig platform: Add Surface platform directory 2020-10-27 12:51:03 +01:00
Makefile platform: Add Surface platform directory 2020-10-27 12:51:03 +01:00