ssi: Add slave autoconnect helper

Added helper function to automatically connect SPI slaves based on the QOM child
nodes of a device. A SSI master device can call this routine to automatically
hook-up all child nodes to its SPI bus.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/hw/ssi.c b/hw/ssi.c
index c47419d57f..2b56357153 100644
--- a/hw/ssi.c
+++ b/hw/ssi.c
@@ -139,3 +139,36 @@ static void ssi_slave_register_types(void)
 }
 
 type_init(ssi_slave_register_types)
+
+typedef struct SSIAutoConnectArg {
+    qemu_irq **cs_linep;
+    SSIBus *bus;
+} SSIAutoConnectArg;
+
+static int ssi_auto_connect_slave(Object *child, void *opaque)
+{
+    SSIAutoConnectArg *arg = opaque;
+    SSISlave *dev = (SSISlave *)object_dynamic_cast(child, TYPE_SSI_SLAVE);
+    qemu_irq cs_line;
+
+    if (!dev) {
+        return 0;
+    }
+
+    cs_line = qdev_get_gpio_in(DEVICE(dev), 0);
+    qdev_set_parent_bus(DEVICE(dev), &arg->bus->qbus);
+    **arg->cs_linep = cs_line;
+    (*arg->cs_linep)++;
+    return 0;
+}
+
+void ssi_auto_connect_slaves(DeviceState *parent, qemu_irq *cs_line,
+                             SSIBus *bus)
+{
+    SSIAutoConnectArg arg = {
+        .cs_linep = &cs_line,
+        .bus = bus
+    };
+
+    object_child_foreach(OBJECT(parent), ssi_auto_connect_slave, &arg);
+}