Re: [BUG] omap: mfd/regulator: twl/core: init order

[Grygorii Strashko <grygorii.strashko@ti.com>]

On 04/13/2013 09:27 PM, Christoph Fritz wrote:
> Hi
>
>   while testing an omap3 board with device tree support I stumbled upon a
> bug which is due to wrong initialization order of twl-core and
> twl-regulator (I suppose): In the boot process they get loaded way too
> late so that a lot of drivers before where configured wrong or just
> refuse to load.
>
> For example the real time clock driver: The RTC kicks in way before
> twl_probe() and due to that it configures its register map wrong
> (at this time twl_priv->twl_id isn't configured yet).
>
> Another example is the omap display subsystem. It (DSS) fails loading
> while trying to register some not yet existent regulators and because it
> lacks EPROBE_DEFER.
>
> USB and MMC is also not working and I'm suspicious of the same cause.
>
> Any ideas?
Hi Christoph,

It happens, because I2C probes execution  have been deferred due to
"pinctrl-single" driver (, which is not ready at i2c bus initialization 
time:

[    0.525939] omap_i2c 48070000.i2c: could not find pctldev for node 
/ocp/pinmux@4a100040/pinmux_i2c1_pins, deferring probe
[    0.526000] platform 48070000.i2c: Driver omap_i2c requests probe 
deferral
[    0.526062] omap_i2c 48072000.i2c: could not find pctldev for node 
/ocp/pinmux@4a100040/pinmux_i2c2_pins, deferring probe
[    0.526092] platform 48072000.i2c: Driver omap_i2c requests probe 
deferral
[    0.526153] omap_i2c 48060000.i2c: could not find pctldev for node 
/ocp/pinmux@4a100040/pinmux_i2c3_pins, deferring probe
[    0.526184] platform 48060000.i2c: Driver omap_i2c requests probe 
deferral
[    0.526245] omap_i2c 48350000.i2c: could not find pctldev for node 
/ocp/pinmux@4a100040/pinmux_i2c4_pins, deferring probe
[    0.526275] platform 48350000.i2c: Driver omap_i2c requests probe 
deferral

I think following change should fix it, could you try it, pls:
diff --git a/drivers/pinctrl/pinctrl-single.c 
b/drivers/pinctrl/pinctrl-single.c
index 5c32e88..b2a9d4b 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -1014,7 +1014,18 @@ static struct platform_driver pcs_driver = {
         },
  };

-module_platform_driver(pcs_driver);
+static int __init pcs_driver_drv_init(void)
+{
+       return platform_driver_register(&pcs_driver);
+}
+postcore_initcall(pcs_driver_drv_init);
+
+static void __exit pcs_driver_drv_exit(void)
+{
+       platform_driver_unregister(&pcs_driver);
+}
+module_exit(pcs_driver_drv_exit);
+

  MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
  MODULE_DESCRIPTION("One-register-per-pin type device tree based 
pinctrl driver");

>   Thanks
>    -- Christoph
>
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