Re: [PATCH V2 05/13] pm80xx : Support for char device.

Jinpu Wang
2020-03-11T17:08:24Z

On Tue, Jan 28, 2020 at 10:43 AM <Deepak.Ukey@microchip.com> wrote:
>
>
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
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> On 22/01/2020 08:50, Deepak.Ukey@microchip.com wrote:
> > -r--r--r-- 1 root root 4096 Jan 21 12:05 running_disparity_error_count
> > ***
> > -r--r--r-- 1 root root 4096 Jan 21 12:05 sas_address
> > lrwxrwxrwx 1 root root 0 Jan 21 11:45 subsystem ->
> > ../../../../../../../class/sas_phy
> > -r--r--r-- 1 root root 4096 Jan 21 12:05 target_port_protocols
> > -rw-r--r-- 1 root root 4096 Jan 21 11:45 uevent
> >
> > Maybe the other stuff provided in the patches are useful, I don't know.
> > But debugfs seems better for that.
> >
> > - 0006-pm80xx-sysfs-attribute-for-number-of-phys
> > - 0007-pm80xx-IOCTL-functionality-to-get-phy-status gets things like Programmed Link Rate, Negotiated Link Rate, PHY Identifier
> > - 0008-pm80xx-IOCTL-functionality-to-get-phy-error provides other things like Invalid Dword Error Count, Disparity Error Count
> > - Thanks for addressing it. We can get this info from /sys/class/sas_phy and /sys/class/sas_port so we will drop these above mentioned three patches from the next - patch series.
> >

> >
> > - 0009-pm80xx-IOCTL-functionality-for-GPIO
> > - 0013-pm80xx-IOCTL-functionality-for-TWI-device
> > - For the above patches management utility passes command specific information to driver through IOCTL structure, which used by driver to frame the command and - send to FW. We are using the IOCTL interface for the same. Please let us know your thought.
>
> So I specifically questioned the SGPIO patch and why it would have an IOCTL, as this function is supported in kernel libsas/SAS transport code as an SMP function.
> > Thank you for your suggestions. We will make use of function supported in libsas.

So basically you only need IOCTL for GPIO and TWI devices, others can
implement via libsas interface or from sysfs directly.

I would like to suggest you do send out other changes without the
IOCTL parts first, and consider again Is it really needed by the user
to control GPIO and TWI, and if there is other way to do it?

Sorry, I don't have a better suggestion!

Regards,
Jack Wang