slimbus: Add Device Tree support for SLIMBUS

Slave devices can be added by listing them as child of a SLIMBUS
controller of_node in the Device Tree.
It is required to specify elemental address, and name of the slave
device.

Change-Id: Ie1b2f8fe58988f0237547a84f1bbb14ce4733eff
Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>

drivers/of/Kconfig

@@ -101,4 +101,10 @@ config OF_MTD
 	depends on MTD
 	def_bool y
 
+config OF_SLIMBUS
+	def_tristate SLIMBUS
+	depends on SLIMBUS
+	help
+	  OpenFirmware SLIMBUS accessors
+
 endmenu # OF

drivers/of/Makefile

@@ -14,3 +14,4 @@ obj-$(CONFIG_OF_PCI)	+= of_pci.o
 obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o
 obj-$(CONFIG_OF_SPMI)	+= of_spmi.o
 obj-$(CONFIG_OF_MTD)	+= of_mtd.o
+obj-$(CONFIG_OF_SLIMBUS)	+= of_slimbus.o

drivers/of/of_slimbus.c

@@ -0,0 +1,83 @@
+/* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/* OF helpers for SLIMbus */
+#include <linux/slimbus/slimbus.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_slimbus.h>
+
+int of_register_slim_devices(struct slim_controller *ctrl)
+{
+	struct device_node *node;
+	struct slim_boardinfo *binfo = NULL;
+	int n = 0;
+	int ret = 0;
+
+	if (!ctrl->dev.of_node)
+		return -EINVAL;
+
+	for_each_child_of_node(ctrl->dev.of_node, node) {
+		struct property *prop;
+		struct slim_device *slim;
+		char *name;
+		prop = of_find_property(node, "elemental-addr", NULL);
+		if (!prop || prop->length != 6) {
+			dev_err(&ctrl->dev, "of_slim: invalid E-addr");
+			continue;
+		}
+		name = kzalloc(SLIMBUS_NAME_SIZE, GFP_KERNEL);
+		if (!name) {
+			dev_err(&ctrl->dev, "of_slim: out of memory");
+			ret = -ENOMEM;
+			goto of_slim_err;
+		}
+		if (of_modalias_node(node, name, SLIMBUS_NAME_SIZE) < 0) {
+			dev_err(&ctrl->dev, "of_slim: modalias failure on %s\n",
+				node->full_name);
+			kfree(name);
+			continue;
+		}
+		slim = kzalloc(sizeof(struct slim_device), GFP_KERNEL);
+		if (!slim) {
+			dev_err(&ctrl->dev, "of_slim: out of memory");
+			ret = -ENOMEM;
+			kfree(name);
+			goto of_slim_err;
+		}
+		memcpy(slim->e_addr, prop->value, 6);
+
+		binfo = krealloc(binfo, (n + 1) * sizeof(struct slim_boardinfo),
+					GFP_KERNEL);
+		if (!binfo) {
+			dev_err(&ctrl->dev, "out of memory");
+			kfree(name);
+			kfree(slim);
+			return -ENOMEM;
+		}
+		slim->name = (const char *)name;
+		binfo[n].bus_num = ctrl->nr;
+		binfo[n].slim_slave = slim;
+		n++;
+	}
+	return slim_register_board_info(binfo, n);
+of_slim_err:
+	n--;
+	while (n >= 0) {
+		kfree(binfo[n].slim_slave->name);
+		kfree(binfo[n].slim_slave);
+	}
+	kfree(binfo);
+	return ret;
+}

include/linux/of_slimbus.h

@@ -0,0 +1,34 @@
+/* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/slimbus/slimbus.h>
+#include <linux/of_irq.h>
+
+#ifdef CONFIG_OF_SLIMBUS
+/*
+ * of_slim_register_devices() - Register devices in the SLIMbus Device Tree
+ * @ctrl: slim_controller which devices should be registered to.
+ *
+ * This routine scans the SLIMbus Device Tree, allocating resources and
+ * creating slim_devices according to the SLIMbus Device Tree
+ * hierarchy. Details of this hierarchy can be found in
+ * Documentation/devicetree/bindings/slimbus. This routine is normally
+ * called from the probe routine of the driver registering as a
+ * slim_controller.
+ */
+extern int of_register_slim_devices(struct slim_controller *ctrl);
+#else
+static int of_register_slim_devices(struct slim_controller *ctrl)
+{
+	return 0;
+}
+#endif /* CONFIG_OF_SLIMBUS */