Re: [PATCH v3 2/3] platform/x86: think-lmi: Add possible_values for ThinkStation

["Mark Pearson" <mpearson-lenovo@squebb.ca>]

On Sat, Mar 18, 2023, at 7:52 PM, Thomas Weißschuh wrote:
> On Sat, Mar 18, 2023 at 01:53:33PM -0400, Mark Pearson wrote:
>> Thanks Thomas
>> 
>> On Sat, Mar 18, 2023, at 12:35 PM, Thomas Weißschuh wrote:
>> > Hi Mark,
>> >
>> > please also CC linux-kernel@vger.kernel.org and previous reviewers.
>> >
>> > On Fri, Mar 17, 2023 at 11:46:34AM -0400, Mark Pearson wrote:
>> >> -static struct kobj_attribute attr_current_val = __ATTR_RW_MODE(current_value, 0600);
>> >> +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
>> >> +		char *buf)
>> >> +{
>> >> +	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
>> >> +
>> >> +	if (setting->possible_values) {
>> >> +		/* Figure out what setting type is as BIOS does not return this */
>> >> +		if (strchr(setting->possible_values, ','))
>> >> +			return sysfs_emit(buf, "enumeration\n");
>> >> +	}
>> >> +	/* Anything else is going to be a string */
>> >> +	return sysfs_emit(buf, "string\n");
>> >> +}
>> >
>> > This patch seems to introduce a lot of churn, is it intentional?
>> Yes(ish). It got cleaned up as the functions were in a weird order when I introduced the is_visible. The actual changes are very small - but it did make it look messier than it really is.
>> Is this a big concern? I know it makes the review a bit more painful and my apologies for that.
>
> Not a big concern. The shuffling around could be done in a dedicated
> patch that explicitly only moves code around.
>
>> >> @@ -1440,6 +1451,25 @@ static int tlmi_analyze(void)
>> >>  			if (ret || !setting->possible_values)
>> >>  				pr_info("Error retrieving possible values for %d : %s\n",
>> >>  						i, setting->display_name);
>> >> +		} else {
>> >> +			/*
>> >> +			 * Older Thinkstations don't support the bios_selections API.
>> >> +			 * Instead they store this as a [Optional:Option1,Option2] section of the
>> >> +			 * name string.
>> >> +			 * Try and pull that out if it's available.
>> >> +			 */
>> >> +			char *item, *optstart, *optend;
>> >> +
>> >> +			if (!tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID)) {
>> >> +				optstart = strstr(item, "[Optional:");
>> >> +				if (optstart) {
>> >> +					optstart += strlen("[Optional:");
>> >> +					optend = strstr(optstart, "]");
>> >> +					if (optend)
>> >> +						setting->possible_values =
>> >> +							kstrndup(optstart, optend - optstart, GFP_KERNEL);
>> >> +				}
>> >> +			}
>> >
>> > The patch now does two things:
>> > 1) Hide the sysfs attributes if the value is not available
>> > 2) Extract the value from the description
>> >
>> > Maybe it could be split in two?
>> Sure. I did contemplate that and then ultimately decided it was all from the same intent so left it. But I can split.
>
> Would look nicer to me, but it's only one opinion.

I have worked through this and it is nicer. Next version will be split (and I unwound some of the code re-org too).
I'm going to hold off a couple of days before pushing the changes for review in case there are other pieces of feedback.

Mark