Morning Andy On 19/01/2021 09:33, Andy Shevchenko wrote: > On Tue, Jan 19, 2021 at 12:11:40AM +0000, Daniel Scally wrote: >> On 18/01/2021 21:19, Daniel Scally wrote: >> I'm more and more confident that this will work, but it has some >> knock-on effects: >> >> The both clk and regulator gpio driver expects to be able to fetch the >> GPIO using devm_gpiod_get(&pdev->dev, "enable", ...). That won't work of >> course, so we need to add another GPIO lookup table so those drivers can >> see the GPIOs. For that, we need to know what dev_name(&pdev->dev) will >> be so we can set the .dev_id member of a gpiod_lookup_table to that >> value, but that isn't set until _after_ the pdev is registered (because >> it has to figure out the id, we can't manually set the IDs because there >> could be more than one instance of int3472-discrete bound to multiple >> PMIC devices, and we don't know which id the current one should have). >> Finally, we can't wait until the device is registered because it >> immediately probes, can't find the GPIO and then fails probe. >> >> It's similar problem that causes us to need the i2c-acpi name format >> macros, but complicated by the dynamic ID part of dev_name(&pdev->dev) >> >> Solving it is a bit of a sticky one; perhaps something like moving the >> dev_set_name() part of platform_device_add() [1] to its own function, >> that's called in both platform_device_alloc() and >> platform_device_register(). That way it would be available before the >> device itself was registered, meaning we could create the lookup table >> before it probes the driver. > See my previous reply. TL;DR: you have to modify clk-gpio.c to export couple of > methods to be able to use it as a library. Ack! Ok, I thought about that the wrong way. I'll take another look tonight then. >> (also, Laurent, if we did it this way we wouldn't be able to also handle >> the led-indicator GPIO here without some fairly major rework) > LED indicators are done as LED class devices (see plenty of examples in PDx86 > drivers: drivers/platform/x86/) And this too - thanks very much
