On Mon, Oct 25, 2021 at 12:42 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: > > 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. Just a side note: MODULE_SOFTDEP() won't work in some (special?) cases when module tools are limited in functionality (e.g. busybox implementation as of today). -- With Best Regards, Andy Shevchenko
