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

[Rajat Khandelwal <rajat.khandelwal@linux.intel.com>]

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@linux.intel.com>
>>>> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
>>>> ---
>>>>
>>>> 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