target/linux/mvebu/patches-3.10/0176-of-irq-create-interrupts-extended-property.patch

   1 From 6dc29d94d92ccc558b946bd57cd8d7cb19d8def1 Mon Sep 17 00:00:00 2001
   2 From: Grant Likely <grant.likely@linaro.org>
   3 Date: Thu, 19 Dec 2013 09:30:47 -0300
   4 Subject: [PATCH 176/203] of/irq: create interrupts-extended property
   5
   6 The standard interrupts property in device tree can only handle
   7 interrupts coming from a single interrupt parent. If a device is wired
   8 to multiple interrupt controllers, then it needs to be attached to a
   9 node with an interrupt-map property to demux the interrupt specifiers
  10 which is confusing. It would be a lot easier if there was a form of the
  11 interrupts property that allows for a separate interrupt phandle for
  12 each interrupt specifier.
  13
  14 This patch does exactly that by creating a new interrupts-extended
  15 property which reuses the phandle+arguments pattern used by GPIOs and
  16 other core bindings.
  17
  18 Signed-off-by: Grant Likely <grant.likely@linaro.org>
  19 Acked-by: Tony Lindgren <tony@atomide.com>
  20 Acked-by: Kumar Gala <galak@codeaurora.org>
  21 [grant.likely: removed versatile platform hunks into separate patch]
  22 Cc: Rob Herring <rob.herring@calxeda.com>
  23
  24 Conflicts:
  25         arch/arm/boot/dts/testcases/tests-interrupts.dtsi
  26         drivers/of/selftest.c
  27 ---
  28  .../bindings/interrupt-controller/interrupts.txt   | 29 +++++++++++++++++-----
  29  drivers/of/irq.c                                   | 16 ++++++++----
  30  2 files changed, 34 insertions(+), 11 deletions(-)
  31
  32 --- a/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
  33 +++ b/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
  34 @@ -4,16 +4,33 @@ Specifying interrupt information for dev
  35  1) Interrupt client nodes
  36  -------------------------
  37
  38 -Nodes that describe devices which generate interrupts must contain an
  39 -"interrupts" property. This property must contain a list of interrupt
  40 -specifiers, one per output interrupt. The format of the interrupt specifier is
  41 -determined by the interrupt controller to which the interrupts are routed; see
  42 -section 2 below for details.
  43 +Nodes that describe devices which generate interrupts must contain an either an
  44 +"interrupts" property or an "interrupts-extended" property. These properties
  45 +contain a list of interrupt specifiers, one per output interrupt. The format of
  46 +the interrupt specifier is determined by the interrupt controller to which the
  47 +interrupts are routed; see section 2 below for details.
  48 +
  49 +  Example:
  50 +       interrupt-parent = <&intc1>;
  51 +       interrupts = <5 0>, <6 0>;
  52
  53  The "interrupt-parent" property is used to specify the controller to which
  54  interrupts are routed and contains a single phandle referring to the interrupt
  55  controller node. This property is inherited, so it may be specified in an
  56 -interrupt client node or in any of its parent nodes.
  57 +interrupt client node or in any of its parent nodes. Interrupts listed in the
  58 +"interrupts" property are always in reference to the node's interrupt parent.
  59 +
  60 +The "interrupts-extended" property is a special form for use when a node needs
  61 +to reference multiple interrupt parents. Each entry in this property contains
  62 +both the parent phandle and the interrupt specifier. "interrupts-extended"
  63 +should only be used when a device has multiple interrupt parents.
  64 +
  65 +  Example:
  66 +       interrupts-extended = <&intc1 5 1>, <&intc2 1 0>;
  67 +
  68 +A device node may contain either "interrupts" or "interrupts-extended", but not
  69 +both. If both properties are present, then the operating system should log an
  70 +error and use only the data in "interrupts".
  71
  72  2) Interrupt controller nodes
  73  -----------------------------
  74 --- a/drivers/of/irq.c
  75 +++ b/drivers/of/irq.c
  76 @@ -293,17 +293,23 @@ int of_irq_map_one(struct device_node *d
  77         if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
  78                 return of_irq_map_oldworld(device, index, out_irq);
  79
  80 +       /* Get the reg property (if any) */
  81 +       addr = of_get_property(device, "reg", NULL);
  82 +
  83         /* Get the interrupts property */
  84         intspec = of_get_property(device, "interrupts", &intlen);
  85 -       if (intspec == NULL)
  86 -               return -EINVAL;
  87 +       if (intspec == NULL) {
  88 +               /* Try the new-style interrupts-extended */
  89 +               res = of_parse_phandle_with_args(device, "interrupts-extended",
  90 +                                               "#interrupt-cells", index, out_irq);
  91 +               if (res)
  92 +                       return -EINVAL;
  93 +               return of_irq_parse_raw(addr, out_irq);
  94 +       }
  95         intlen /= sizeof(*intspec);
  96
  97         pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
  98
  99 -       /* Get the reg property (if any) */
 100 -       addr = of_get_property(device, "reg", NULL);
 101 -
 102         /* Look for the interrupt parent. */
 103         p = of_irq_find_parent(device);
 104         if (p == NULL)