Re: Regression in 4.18-rc1 caused by regulator: arizona-ldo1: Look up a descriptor and pass to the core

[Charles Keepax <ckeepax@opensource.cirrus.com>]

On Mon, Jun 18, 2018 at 07:14:10PM +0200, Matthias Reichl wrote:
> Commit e1739e86f0cb9c48e8745a610e6981a4e24cadad breaks reading
> the wlf,ldoena property from device tree. This causes ldo1 to
> stay off and thus arizona device detection to fail:
> 
> [    4.495958] of_get_named_gpiod_flags: parsed 'wlf,reset' property of node '/s
> oc/spi@7e204000/wm5102@1[0]' - status (0)
> [    4.509756] arizona-ldo1 arizona-ldo1: GPIO lookup for consumer wlf,ldoena
> [    4.511339] arizona-ldo1 arizona-ldo1: using lookup tables for GPIO lookup
> [    4.511351] arizona-ldo1 arizona-ldo1: No GPIO consumer wlf,ldoena found
> [    4.511413] LDO1: supplied by RPi-Cirrus 1v8
> [    4.549164] arizona spi0.1: Unknown device ID: 0
> 
> With this commit reverted the ldoena GPIO is properly found and
> asserted high and the arizona device type is read successfully:
> 
> [    4.630445] of_get_named_gpiod_flags: parsed 'wlf,reset' property of node '/s
> oc/spi@7e204000/wm5102@1[0]' - status (0)
> [    4.647622] of_get_named_gpiod_flags: parsed 'wlf,ldoena' property of node '/soc/spi@7e204000/wm5102@1[0]' - status (0)
> [    4.666100] arizona spi0.1: WM5102 revision C
> 
> I've tested this on a Raspberry Pi 3 with upstream 4.18-rc1,
> the Cirrus Logic Audio Card from Element 14 (using a WM5102
> connected via SPI) and the downstream card driver added as
> a module.
> 
> Both wlf,reset and wlf,ldoena properties are defined in
> the wm5102 devicetree node:
> 
> wm5102@1{
> 	compatible = "wlf,wm5102";
> 	reg = <1>;
> 	...
> 	wlf,reset = <&gpio 17 0>;
> 	wlf,ldoena = <&gpio 22 0>;
> 	...
> };
> 
> If I understand the code correctly the cuplrit seems to be that
> with this patch the gpio is looked up from the arizona-ldo1 dev,
> which has a NULL of_node:
> 
> config.ena_gpiod = devm_gpiod_get_optional(&pdev->dev, "wlf,ldoena", ...
> 
> The old version did an of lookup in the parent (arizona) dev, which
> contains the of_node with wlf,ldoena:
> 
> arizona_ldo1_common_init:
> 	struct device *parent_dev = pdev->dev.parent;
> 	struct regulator_config config = { };
> 	...
> 	config.dev = parent_dev;
> 	...
> 	arizona_ldo1_of_get_pdata(pdata, config, ...
> 
> arizona_ldo1_of_get_pdata:
> 	struct device_node *np = config->dev->of_node;
> 	...
> 	pdata->ldoena = of_get_named_gpio(np, "wlf,ldoena", 0);
> 

Urgh.. sorry about that. I did test that patch but it seems I
messed it up. On our boards the LDOENA defaults to on so I missed
that it wasn't getting configured anymore.

I think we just need to not use the devm version of the
get_optional and pass the correct device. I will get a patch
ready this morning and ping it through for testing.

Thanks,
Charles