| Message ID | 1224772209.4082.61.camel@galileo.recco.de (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Oct 23, 2008, at 9:30 AM, Wolfgang Ocker wrote: > --- linux-2.6.27.2/Documentation/powerpc/booting-without- > of.txt.of_gpiospecbase 2008-10-18 19:57:22.000000000 +0200 > +++ linux-2.6.27.2/Documentation/powerpc/booting-without-of.txt > 2008-10-23 16:23:07.000000000 +0200 > @@ -2580,12 +2582,17 @@ > Every GPIO controller node must have #gpio-cells property defined, > this information will be used to translate gpio-specifiers. > > +Optional properties: > + base: first GPIO number handled by this controller; default is -1, > + meaning dynamic ID allocation "default -1" doesn't make any sense. I assume you mean if the property doesn't it exist the behavior is "dynamic ID allocation" > > + > Example of two SOC GPIO banks defined as gpio-controller nodes: > > qe_pio_a: gpio-controller@1400 { > #gpio-cells = <2>; > compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank"; > reg = <0x1400 0x18>; > + base = < 0x20 >; > gpio-controller; > }; >
--- linux-2.6.27.2/drivers/of/gpio.c.of_gpiospecbase 2008-10-18 19:57:22.000000000 +0200 +++ linux-2.6.27.2/drivers/of/gpio.c 2008-10-23 10:55:19.000000000 +0200 @@ -164,6 +164,8 @@ int ret = -ENOMEM; struct of_gpio_chip *of_gc = &mm_gc->of_gc; struct gpio_chip *gc = &of_gc->gc; + const int *basep; + int baselen; gc->label = kstrdup(np->full_name, GFP_KERNEL); if (!gc->label) @@ -173,7 +175,11 @@ if (!mm_gc->regs) goto err1; - gc->base = -1; + basep = of_get_property(np, "base", &baselen); + if (!basep || baselen != sizeof(*basep)) + gc->base = -1; + else + gc->base = *basep; if (!of_gc->xlate) of_gc->xlate = of_gpio_simple_xlate; --- linux-2.6.27.2/Documentation/powerpc/booting-without-of.txt.of_gpiospecbase 2008-10-18 19:57:22.000000000 +0200 +++ linux-2.6.27.2/Documentation/powerpc/booting-without-of.txt 2008-10-23 16:23:07.000000000 +0200 @@ -2580,12 +2582,17 @@ Every GPIO controller node must have #gpio-cells property defined, this information will be used to translate gpio-specifiers. +Optional properties: + base: first GPIO number handled by this controller; default is -1, + meaning dynamic ID allocation + Example of two SOC GPIO banks defined as gpio-controller nodes: qe_pio_a: gpio-controller@1400 { #gpio-cells = <2>; compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank"; reg = <0x1400 0x18>; + base = < 0x20 >; gpio-controller; };
The GPIOLIB allows the specification of a base gpio number for a controller. That is not possible using OF. Instead, free gpio numbers are assigned. In order to allow static, predefined gpio numbers, a base property in the gpio controller node specifies the first gpio number. v2: added description of base property in doc Signed-off-by: Wolfgang Ocker <weo@reccoware.de> ---