of/irq: Fix lookup to use 'interrupts-extended' property first

In case the Device Tree blob passed by the boot agent supplies both an
'interrupts-extended' and an 'interrupts' property in order to allow for
older kernels to be usable, prefer the new-style 'interrupts-extended'
property which conveys a lot more information.

This allows us to have bootloaders willingly maintaining backwards
compatibility with older kernels without entirely deprecating the
'interrupts' property.

Update the bindings documentation to describe a situation where both the
'interrupts-extended' and the 'interrupts' property are present, and
which one takes precedence over the other.

Cc: stable@vger.kernel.org # 3.13+
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This commit is contained in:
Florian Fainelli 2014-08-06 13:02:27 -07:00 committed by Grant Likely
parent b951f9dc7f
commit a9ecdc0fdc
2 changed files with 16 additions and 13 deletions

View File

@ -4,11 +4,13 @@ Specifying interrupt information for devices
1) Interrupt client nodes
-------------------------
Nodes that describe devices which generate interrupts must contain an either an
"interrupts" property or an "interrupts-extended" property. These properties
contain a list of interrupt specifiers, one per output interrupt. The format of
the interrupt specifier is determined by the interrupt controller to which the
interrupts are routed; see section 2 below for details.
Nodes that describe devices which generate interrupts must contain an
"interrupts" property, an "interrupts-extended" property, or both. If both are
present, the latter should take precedence; the former may be provided simply
for compatibility with software that does not recognize the latter. These
properties contain a list of interrupt specifiers, one per output interrupt. The
format of the interrupt specifier is determined by the interrupt controller to
which the interrupts are routed; see section 2 below for details.
Example:
interrupt-parent = <&intc1>;

View File

@ -301,16 +301,17 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar
/* Get the reg property (if any) */
addr = of_get_property(device, "reg", NULL);
/* Try the new-style interrupts-extended first */
res = of_parse_phandle_with_args(device, "interrupts-extended",
"#interrupt-cells", index, out_irq);
if (!res)
return of_irq_parse_raw(addr, out_irq);
/* Get the interrupts property */
intspec = of_get_property(device, "interrupts", &intlen);
if (intspec == NULL) {
/* Try the new-style interrupts-extended */
res = of_parse_phandle_with_args(device, "interrupts-extended",
"#interrupt-cells", index, out_irq);
if (res)
return -EINVAL;
return of_irq_parse_raw(addr, out_irq);
}
if (intspec == NULL)
return -EINVAL;
intlen /= sizeof(*intspec);
pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);