RE: [PATCH v10 11/15] platform/x86: dell-smbios-smm: test for WSMT

From: Mario.Limonciello
Date: Thu Oct 19 2017 - 14:12:35 EST


> -----Original Message-----
> From: Pali RohÃr [mailto:pali.rohar@xxxxxxxxx]
> Sent: Thursday, October 19, 2017 1:09 PM
> To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> Cc: dvhart@xxxxxxxxxxxxx; Andy Shevchenko <andy.shevchenko@xxxxxxxxx>;
> LKML <linux-kernel@xxxxxxxxxxxxxxx>; platform-driver-x86@xxxxxxxxxxxxxxx; Andy
> Lutomirski <luto@xxxxxxxxxx>; quasisec@xxxxxxxxxx; rjw@xxxxxxxxxxxxx;
> mjg59@xxxxxxxxxx; hch@xxxxxx; Greg KH <greg@xxxxxxxxx>; Alan Cox
> <gnomes@xxxxxxxxxxxxxxxxxxx>
> Subject: Re: [PATCH v10 11/15] platform/x86: dell-smbios-smm: test for WSMT
>
> On Thursday 19 October 2017 12:50:14 Mario Limonciello wrote:
> > +/* When enabled this indicates that SMM won't work */
> > +static bool test_wsmt_enabled(void)
> > +{
> > + struct calling_interface_token *token;
> > +
> > + /* if token doesn't exist, SMM will work */
> > + token = dell_smbios_find_token(WSMT_EN_TOKEN);
> > + if (!token)
> > + return false;
> > +
> > + /* if token exists, try to access over SMM */
> > + buffer->class = CLASS_TOKEN_READ;
> > + buffer->select = SELECT_TOKEN_STD;
> > + memset(buffer, 0, sizeof(struct calling_interface_buffer));
> > + buffer->input[0] = token->location;
> > + dell_smbios_smm_call(buffer);
> > +
> > + /* if lookup failed, we know WSMT was enabled */
> > + if (buffer->output[0] != 0)
> > + return true;
> > +
> > + /* query token status if it didn't fail */
> > + return (buffer->output[1] == token->value);
> > +}
> > +
> > static int __init dell_smbios_smm_init(void)
> > {
> > int ret;
> > @@ -115,6 +140,13 @@ static int __init dell_smbios_smm_init(void)
> >
> > dmi_walk(find_cmd_address, NULL);
> >
> > + ret = test_wsmt_enabled();
>
> ret is int, but test_wsmt_enabled() returns bool.

Yes, ret is re-used within this method.
0, 1 enum is a subset of int, so this seemed like a logical thing to me to do.