Le jeu. 24 janv. 2019 à 19:46, Stephen Boyd [off-list ref] a 
écrit :

Quoting Paul Cercueil (2019-01-24 12:46:28)

quoted

 Le jeu. 24 janv. 2019 à 16:28, Stephen Boyd [off-list ref] a
 écrit :
 > Quoting Guenter Roeck (2019-01-23 10:01:55)
 >>  On Wed, Jan 23, 2019 at 02:25:53PM -0300, Paul Cercueil wrote:
 >>  > Hi,
 >>  >
 >>  > Le mer. 23 janv. 2019 Ã  11:31, Guenter Roeck
 >> [off-list ref] a écrit :
 >>  > >On 1/23/19 4:58 AM, Mathieu Malaterre wrote:
 >>  > >>On Wed, Dec 12, 2018 at 11:09 PM Paul Cercueil
 >> [off-list ref]
 >>  > >>wrote:
 >>  > >>>
 >>  > >>>From: Maarten ter Huurne [off-list ref]
 >>  > >>>
 >>  > >>>OST is the OS Timer, a 64-bit timer/counter with buffered
 >> reading.
 >>  > >>>
 >>  > >>>SoCs before the JZ4770 had (if any) a 32-bit OST; the 
JZ4770
 >> and
 >>  > >>>JZ4780 have a 64-bit OST.
 >>  > >>>
 >>  > >>>This driver will register both a clocksource and a 
sched_clock
 >> to the
 >>  > >>>system.
 >>  > >>>
 >>  > >>>Signed-off-by: Maarten ter Huurne [off-list ref]
 >>  > >>>Signed-off-by: Paul Cercueil [off-list ref]
 >>  > >>>---
 >>  > >>>
 >>  > >>>Notes:
 >>  > >>>      v5: New patch
 >>  > >>>
 >>  > >>>      v6: - Get rid of SoC IDs; pass pointer to
 >> ingenic_ost_soc_info
 >>  > >>>as
 >>  > >>>            devicetree match data instead.
 >>  > >>>          - Use device_get_match_data() instead of the of_*
 >> variant
 >>  > >>>          - Handle error of dev_get_regmap() properly
 >>  > >>>
 >>  > >>>      v7: Fix section mismatch by using
 >>  > >>>builtin_platform_driver_probe()
 >>  > >>>
 >>  > >>>      v8: builtin_platform_driver_probe() does not work
 >> anymore in
 >>  > >>>          4.20-rc6? The probe function won't be called. 
Work
 >> around
 >>  > >>>this
 >>  > >>>          for now by using late_initcall.
 >>  > >>>
 >>  > >
 >>  > >Did anyone notice this ? Either something is wrong with the
 >> driver, or
 >>  > >with the kernel core. Hacking around it seems like the worst
 >> possible
 >>  > >"solution".
 >>  >
 >>  > I can confirm it still happens on 5.0-rc3.
 >>  >
 >>  > Just to explain what I'm doing:
 >>  >
 >>  > My ingenic-timer driver probes with 
builtin_platform_driver_probe
 >> (this
 >>  > works),
 >>  > and then calls of_platform_populate to probe its children. 
This
 >> driver,
 >>  > ingenic-ost, is one of them, and will fail to probe with
 >>  > builtin_platform_driver_probe.
 >>  >
 >>
 >>  The big question is _why_ it fails to probe.
 >>
 >
 > Are you sharing the device tree node between a 'normal' platform
 > device
 > driver and something more low level DT that marks the device's 
backing
 > DT node as OF_POPULATED early on? That's my only guess why it's 
not
 > working.

 I do, but I clear the OF_POPULATED flag so that it is then probed 
as a
 normal platform device, and it's not on this driver's node but its
 parent.

Where do you clear the OF_POPULATED flag?

In the ingenic-timer driver introduced in patch [04/26], inside the 
probe function.