Re: [PATCH] mfd: rk8xx: register devices again with PLATFORM_DEVID_NONE

[Neil Armstrong]

Hi,

On 16/11/2023 12:35, Sebastian Reichel wrote:
> Hi,
>
> On Thu, Nov 16, 2023 at 09:53:05AM +0100, Neil Armstrong wrote:
> > Since commit 210f418f8ace ("mfd: rk8xx: Add rk806 support"), devices are
> > registered with "0" as id, causing devices to not have an automatic device id
> > and prevents having multiple RK8xx PMICs on the same system.
>
> They are not registered with "0" as ID - they are registered without
> any ID at all, because their cells have PLATFORM_DEVID_NONE.
>
> > This fixes a regression while booting the Odroid Go Ultra on v6.6.1:
> > sysfs: cannot create duplicate filename '/bus/platform/devices/rk808-clkout'
>
> ^ which you can see here. There is no ".0" suffix at the end of the
> sysfs path.
>
> > CPU: 3 PID: 97 Comm: kworker/u12:2 Not tainted 6.6.1 #1
> > Hardware name: Hardkernel ODROID-GO-Ultra (DT)
> > Workqueue: events_unbound deferred_probe_work_func
> > Call trace:
> > dump_backtrace+0x9c/0x11c
> > show_stack+0x18/0x24
> > dump_stack_lvl+0x78/0xc4
> > dump_stack+0x18/0x24
> > sysfs_warn_dup+0x64/0x80
> > sysfs_do_create_link_sd+0xf0/0xf8
> > sysfs_create_link+0x20/0x40
> > bus_add_device+0x114/0x160
> > device_add+0x3f0/0x7cc
> > platform_device_add+0x180/0x270
> > mfd_add_device+0x390/0x4a8
> > devm_mfd_add_devices+0xb0/0x150
> > rk8xx_probe+0x26c/0x410
> > rk8xx_i2c_probe+0x64/0x98
> > i2c_device_probe+0x104/0x2e8
> > really_probe+0x184/0x3c8
> > __driver_probe_device+0x7c/0x16c
> > driver_probe_device+0x3c/0x10c
> > __device_attach_driver+0xbc/0x158
> > bus_for_each_drv+0x80/0xdc
> > __device_attach+0x9c/0x1ac
> > device_initial_probe+0x14/0x20
> > bus_probe_device+0xac/0xb0
> > deferred_probe_work_func+0xa0/0xf4
> > process_one_work+0x1bc/0x378
> > worker_thread+0x1dc/0x3d4
> > kthread+0x104/0x118
> > ret_from_fork+0x10/0x20
> > rk8xx-i2c 0-001c: error -EEXIST: failed to add MFD devices
> > rk8xx-i2c: probe of 0-001c failed with error -17
> >
> > Fixes: 210f418f8ace ("mfd: rk8xx: Add rk806 support")
> > Reported-by: Adam Green <greena88@xxxxxxxxx>
> > Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> > ---
> > Lee, This is only a fix for the regression, as discussed with Sebastian at [1],
> > the driver would require some more cleanup to cleanly register all devices with
> > PLATFORM_DEVID_AUTO. I plan to send this later on.
> >
> > [1] https://lore.kernel.org/all/20231115180050.5r5xukttz27vviyi@xxxxxxxxxxxxxxxxxxxxxx/
>
> NAK, this would break rk806. You can use PLATFORM_DEVID_AUTO instead,
> since that has special handling in devm_mfd_add_devices and will
> ignore the PLATFORM_DEVID_NONE specified by the cells.

You're right, I was preparing the patch cleanup and it's clear it will
break rk806 because I just saw you specifically added PLATFORM_DEVID_AUTO
to rk806 cells.

I'll send a v2.

Thanks,
Neil

> Greetings,
>
> -- Sebastian
>
> > ---
> >   drivers/mfd/rk8xx-core.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mfd/rk8xx-core.c b/drivers/mfd/rk8xx-core.c
> > index c47164a3ec1d..58d8dec7ac02 100644
> > --- a/drivers/mfd/rk8xx-core.c
> > +++ b/drivers/mfd/rk8xx-core.c
> > @@ -684,7 +684,7 @@ int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap
> >   					     pre_init_reg[i].addr);
> >   	}
> >   
> > -	ret = devm_mfd_add_devices(dev, 0, cells, nr_cells, NULL, 0,
> > +	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, cells, nr_cells, NULL, 0,
> >   			      regmap_irq_get_domain(rk808->irq_data));
> >   	if (ret)
> >   		return dev_err_probe(dev, ret, "failed to add MFD devices\n");
> >
> > ---
> > base-commit: f31817cbcf48d191faee7cebfb59197d2048cd64
> > change-id: 20231116-topic-amlogic-upstream-fix-rk8xx-devid-auto-59ce0d1b738a
> >
> > Best regards,
> > --
> > Neil Armstrong <neil.armstrong@xxxxxxxxxx>