Re: [PATCH v4] usb: typec: intel_pmc_mux: Expose IOM port status to debugfs

[Rajat Khandelwal]

Hi,

On 5/22/2023 9:56 PM, Greg KH wrote:
> On Mon, May 22, 2023 at 03:24:13PM +0530, Rajat Khandelwal wrote:
> > Hi,
> >
> > On 5/22/2023 1:07 PM, Greg KH wrote:
> > > On Mon, May 22, 2023 at 12:33:43PM +0530, Rajat Khandelwal wrote:
> > > > IOM status has a crucial role during debugging to check the
> > > > current state of the type-C port.
> > > > There are ways to fetch the status, but all those require the
> > > > IOM port status offset, which could change with platform.
> > > >
> > > > Make a debugfs directory for intel_pmc_mux and expose the status
> > > > under it per port basis.
> > > >
> > > > Signed-off-by: Rajat Khandelwal <rajat.khandelwal@xxxxxxxxxxxxxxx>
> > > > Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> > > > ---
> > > >
> > > > v4:
> > > > 1. Maintain a root directory for PMC module and incorporate devices
> > > > under it
> > > > 2. Add the debugfs module under '/sys/kernel/debug/usb'
> > > > 3. Use the platform device 'pmc->dev' to assign the device's name
> > > >
> > > > v3: Allocate the debugfs directory name for the platform device with
> > > > its ACPI dev name included
> > > >
> > > > v2:
> > > > 1. Remove static declaration of the debugfs root for 'intel_pmc_mux'
> > > > 2. Remove explicitly defined one-liner functions
> > > >
> > > >    drivers/usb/typec/mux/intel_pmc_mux.c | 54 ++++++++++++++++++++++++++-
> > > >    1 file changed, 53 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c
> > > > index 34e4188a40ff..f400094c76f2 100644
> > > > --- a/drivers/usb/typec/mux/intel_pmc_mux.c
> > > > +++ b/drivers/usb/typec/mux/intel_pmc_mux.c
> > > > @@ -15,6 +15,8 @@
> > > >    #include <linux/usb/typec_mux.h>
> > > >    #include <linux/usb/typec_dp.h>
> > > >    #include <linux/usb/typec_tbt.h>
> > > > +#include <linux/debugfs.h>
> > > > +#include <linux/usb.h>
> > > >    #include <asm/intel_scu_ipc.h>
> > > > @@ -143,8 +145,14 @@ struct pmc_usb {
> > > >    	struct acpi_device *iom_adev;
> > > >    	void __iomem *iom_base;
> > > >    	u32 iom_port_status_offset;
> > > > +
> > > > +#ifdef CONFIG_DEBUG_FS
> > > > +	struct dentry *dentry;
> > > > +#endif
> > > No need for the #ifdef anymore, right?  In fact, I think it will break
> > > the build if you have it this way and CONFIG_DEBUG_FS is not enabled,
> > > right?
> > I guess you're right. Maybe it'd have been fine if the rest of the
> > debugfs stuff was also enclosed within the conditional macros.
> Which is not needed and not good kernel coding style, so it's right that
> they are not there.

Sure.

> > Anyways, removing it seems appropriate now.
> >
> > Also, is it OK to send you v5 on the public list directly?
> Where else would you send it?

I was under the impression that you'd again require the review
internally under Intel before releasing out to public list.
Anyways, sending out v5.

Thanks
Rajat

> confused,
>
> greg k-h