kern/157070: Improve API description in gpio_if.m

[Henrik Brix Andersen]

>Number:         157070
>Category:       kern
>Synopsis:       Improve API description in gpio_if.m
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Sun May 15 18:00:21 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Henrik Brix Andersen
>Release:        FreeBSD 9.0-CURRENT i386
>Organization:
>Environment:
System: FreeBSD drpepper.brixandersen.dk 9.0-CURRENT FreeBSD 9.0-CURRENT #3 r221961: Sun May 15 17:11:34 CEST 2011 root at drpepper.brixandersen.dk:/usr/obj/usr/home/brix/projects/freebsd/src/head/sys/GENERIC i386


	
>Description:
The API description for the GPIO_PIN_MAX() method is misleading.  The function should provide the maximum supported pin_num, not the total number of pins.

Most (if not all) in-tree GPIO drivers already name the second argument to this function 'maxpin', which seems less confusing.

>How-To-Repeat:
	
>Fix:
The following patch improves the API description and renames the second argument to better reflect the intent.

--- gpio_if.m.diff begins here ---
Index: sys/dev/gpio/gpio_if.m
===================================================================
--- sys/dev/gpio/gpio_if.m	(revision 221961)
+++ sys/dev/gpio/gpio_if.m	(working copy)
@@ -32,11 +32,11 @@
 INTERFACE gpio;
 
 #
-# Get total number of pins
+# Get the maximum pin_num
 #
 METHOD int pin_max {
 	device_t dev;
-	int *npins;
+	int *maxpin;
 };
 
 #
--- gpio_if.m.diff ends here ---


>Release-Note:
>Audit-Trail:
>Unformatted: