[PATCH v3 04/10] OF: import bus/device related functions from Linux OF API
Sebastian Hesselbarth
sebastian.hesselbarth at gmail.com
Tue Jul 2 14:14:33 EDT 2013
This imports some bus and device related functions from Linux OF API
with some modifcations for Barebox.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
---
Changelog:
v1->v2:
- check for existing devices on of_platform_device_create
- remove auxdata lookup from doxygen header
- fix whitespace damage (Reported by Sascha Hauer)
Cc: barebox at lists.infradead.org
---
drivers/of/Makefile | 2 +-
drivers/of/platform.c | 321 +++++++++++++++++++++++++++++++++++++++++++++++++
include/of.h | 18 +++
3 files changed, 340 insertions(+), 1 deletions(-)
create mode 100644 drivers/of/platform.c
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index b8add0b..186074e 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -1,4 +1,4 @@
-obj-y += address.o base.o fdt.o
+obj-y += address.o base.o fdt.o platform.o
obj-$(CONFIG_OFTREE_MEM_GENERIC) += mem_generic.o
obj-$(CONFIG_GPIOLIB) += gpio.o
obj-y += partition.o
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
new file mode 100644
index 0000000..e75a69b
--- /dev/null
+++ b/drivers/of/platform.c
@@ -0,0 +1,321 @@
+/*
+ * platform.c - bus/device related devicetree functions
+ *
+ * Copyright (c) 2012 Sascha Hauer <s.hauer at pengutronix.de>, Pengutronix
+ *
+ * based on Linux devicetree support
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 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 <common.h>
+#include <malloc.h>
+#include <of.h>
+#include <of_address.h>
+#include <linux/amba/bus.h>
+
+/**
+ * of_find_device_by_node - Find the platform_device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Returns platform_device pointer, or NULL if not found
+ */
+struct device_d *of_find_device_by_node(struct device_node *np)
+{
+ struct device_d *dev;
+ for_each_device(dev)
+ if (dev->device_node == np)
+ return dev;
+ return NULL;
+}
+EXPORT_SYMBOL(of_find_device_by_node);
+
+/**
+ * of_device_make_bus_id - Use the device node data to assign a unique name
+ * @dev: pointer to device structure that is linked to a device tree node
+ *
+ * This routine will first try using either the dcr-reg or the reg property
+ * value to derive a unique name. As a last resort it will use the node
+ * name followed by a unique number.
+ */
+static void of_device_make_bus_id(struct device_d *dev)
+{
+ static int bus_no_reg_magic;
+ struct device_node *np = dev->device_node;
+ const __be32 *reg, *addrp;
+ u64 addr;
+ char *name, *at;
+
+ name = xstrdup(np->name);
+ at = strchr(name, '@');
+ if (at)
+ *at = '\0';
+
+#ifdef CONFIG_PPC_DCR
+ /*
+ * If it's a DCR based device, use 'd' for native DCRs
+ * and 'D' for MMIO DCRs.
+ */
+ reg = of_get_property(np, "dcr-reg", NULL);
+ if (reg) {
+#ifdef CONFIG_PPC_DCR_NATIVE
+ snprintf(dev->name, MAX_DRIVER_NAME, "d%x.%s", *reg, name);
+#else /* CONFIG_PPC_DCR_NATIVE */
+ u64 addr = of_translate_dcr_address(np, *reg, NULL);
+ if (addr != OF_BAD_ADDR) {
+ snprintf(dev->name, MAX_DRIVER_NAME, "D%llx.%s",
+ (unsigned long long)addr, name);
+ free(name);
+ return;
+ }
+#endif /* !CONFIG_PPC_DCR_NATIVE */
+ }
+#endif /* CONFIG_PPC_DCR */
+
+ /*
+ * For MMIO, get the physical address
+ */
+ reg = of_get_property(np, "reg", NULL);
+ if (reg) {
+ if (of_can_translate_address(np)) {
+ addr = of_translate_address(np, reg);
+ } else {
+ addrp = of_get_address(np, 0, NULL, NULL);
+ if (addrp)
+ addr = of_read_number(addrp, 1);
+ else
+ addr = OF_BAD_ADDR;
+ }
+ if (addr != OF_BAD_ADDR) {
+ snprintf(dev->name, MAX_DRIVER_NAME, "%llx.%s",
+ (unsigned long long)addr, name);
+ free(name);
+ return;
+ }
+ }
+
+ /*
+ * No BusID, use the node name and add a globally incremented counter
+ */
+ snprintf(dev->name, MAX_DRIVER_NAME, "%s.%d", name, bus_no_reg_magic++);
+ free(name);
+}
+
+/**
+ * of_platform_device_create - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @parent: device model parent device.
+ *
+ * Returns pointer to created platform device, or NULL if a device was not
+ * registered. Unavailable devices will not get registered.
+ */
+static struct device_d *of_platform_device_create(struct device_node *np,
+ struct device_d *parent)
+{
+ struct device_d *dev;
+ struct resource *res = NULL, temp_res;
+ int i, j, ret, num_reg = 0, match;
+
+ if (!of_device_is_available(np))
+ return NULL;
+
+ /* count the io resources */
+ if (of_can_translate_address(np))
+ while (of_address_to_resource(np, num_reg, &temp_res) == 0)
+ num_reg++;
+
+ /* Populate the resource table */
+ if (num_reg) {
+ res = xzalloc(sizeof(*res) * num_reg);
+ for (i = 0; i < num_reg; i++) {
+ ret = of_address_to_resource(np, i, &res[i]);
+ if (ret) {
+ free(res);
+ return NULL;
+ }
+ }
+
+ /*
+ * A device may already be registered as platform_device.
+ * Instead of registering the same device again, just
+ * add this node to the existing device.
+ */
+ for_each_device(dev) {
+ if (!dev->resource)
+ continue;
+
+ for (i = 0, match = 0; i < num_reg; i++)
+ for (j = 0; j < dev->num_resources; j++)
+ if (dev->resource[j].start ==
+ res[i].start &&
+ dev->resource[j].end ==
+ res[i].end) {
+ match++;
+ break;
+ }
+
+ /* check if all address resources match */
+ if (match == num_reg) {
+ debug("connecting %s to %s\n",
+ np->name, dev_name(dev));
+ dev->device_node = np;
+ free(res);
+ return dev;
+ }
+ }
+ }
+
+ debug("register device 0x%08x\n",
+ (num_reg) ? dev->resource[0].start : (-1));
+
+ /* setup generic device info */
+ dev = xzalloc(sizeof(*dev));
+ dev->id = DEVICE_ID_SINGLE;
+ dev->device_node = np;
+ dev->parent = parent;
+ dev->resource = res;
+ dev->num_resources = num_reg;
+ of_device_make_bus_id(dev);
+
+ ret = platform_device_register(dev);
+ if (!ret)
+ return dev;
+
+ free(dev);
+ if (num_reg)
+ free(res);
+ return NULL;
+}
+
+#ifdef CONFIG_ARM_AMBA
+static struct device_d *of_amba_device_create(struct device_node *np)
+{
+ struct amba_device *dev;
+ int ret;
+
+ debug("Creating amba device %s\n", np->full_name);
+
+ if (!of_device_is_available(np))
+ return NULL;
+
+ dev = xzalloc(sizeof(*dev));
+
+ /* setup generic device info */
+ dev->dev.id = DEVICE_ID_SINGLE;
+ dev->dev.device_node = np;
+ of_device_make_bus_id(&dev->dev);
+
+ ret = of_address_to_resource(np, 0, &dev->res);
+ if (ret)
+ goto amba_err_free;
+
+ dev->dev.resource = &dev->res;
+ dev->dev.num_resources = 1;
+
+ /* Allow the HW Peripheral ID to be overridden */
+ of_property_read_u32(np, "arm,primecell-periphid", &dev->periphid);
+
+ debug("register device 0x%08x\n", dev->dev.resource[0].start);
+
+ ret = amba_device_add(dev);
+ if (ret)
+ goto amba_err_free;
+
+ return &dev->dev;
+
+amba_err_free:
+ free(dev);
+ return NULL;
+}
+#else /* CONFIG_ARM_AMBA */
+static inline struct amba_device *of_amba_device_create(struct device_node *np)
+{
+ return NULL;
+}
+#endif /* CONFIG_ARM_AMBA */
+
+/**
+ * of_platform_bus_create() - Create a device for a node and its children.
+ * @bus: device node of the bus to instantiate
+ * @matches: match table for bus nodes
+ * @parent: parent for new device, or NULL for top level.
+ *
+ * Creates a platform_device for the provided device_node, and optionally
+ * recursively create devices for all the child nodes.
+ */
+static int of_platform_bus_create(struct device_node *bus,
+ const struct of_device_id *matches,
+ struct device_d *parent)
+{
+ struct device_node *child;
+ struct device_d *dev;
+ int rc = 0;
+
+ /* Make sure it has a compatible property */
+ if (!of_get_property(bus, "compatible", NULL)) {
+ pr_debug("%s() - skipping %s, no compatible prop\n",
+ __func__, bus->full_name);
+ return 0;
+ }
+
+ if (of_device_is_compatible(bus, "arm,primecell")) {
+ of_amba_device_create(bus);
+ return 0;
+ }
+
+ dev = of_platform_device_create(bus, parent);
+ if (!dev || !of_match_node(matches, bus))
+ return 0;
+
+ for_each_child_of_node(bus, child) {
+ pr_debug(" create child: %s\n", child->full_name);
+ rc = of_platform_bus_create(child, matches, dev);
+ if (rc)
+ break;
+ }
+ return rc;
+}
+
+/**
+ * of_platform_populate() - Populate platform_devices from device tree data
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table, NULL to use the default
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * This function walks the device tree given by @root node and creates devices
+ * from nodes. It requires all device nodes to have a 'compatible' property,
+ * and it is suitable for creating devices which are children of the root
+ * node.
+ *
+ * Returns 0 on success, < 0 on failure.
+ */
+int of_platform_populate(struct device_node *root,
+ const struct of_device_id *matches,
+ struct device_d *parent)
+{
+ struct device_node *child;
+ int rc = 0;
+
+ if (!root)
+ root = of_find_node_by_path("/");
+ if (!root)
+ return -EINVAL;
+
+ for_each_child_of_node(root, child) {
+ rc = of_platform_bus_create(child, matches, parent);
+ if (rc)
+ break;
+ }
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(of_platform_populate);
diff --git a/include/of.h b/include/of.h
index 8cab797..f1f555f 100644
--- a/include/of.h
+++ b/include/of.h
@@ -61,6 +61,7 @@ struct of_reserve_map *of_get_reserve_map(void);
void of_clean_reserve_map(void);
void fdt_add_reserve_map(void *fdt);
+struct device_d;
struct driver_d;
int of_fix_tree(struct device_node *);
@@ -221,6 +222,11 @@ extern int of_modalias_node(struct device_node *node, char *modalias, int len);
extern struct device_node *of_get_root_node(void);
extern int of_set_root_node(struct device_node *node);
+extern int of_platform_populate(struct device_node *root,
+ const struct of_device_id *matches,
+ struct device_d *parent);
+extern struct device_d *of_find_device_by_node(struct device_node *np);
+
int of_parse_partitions(struct cdev *cdev, struct device_node *node);
int of_device_is_stdout_path(struct device_d *dev);
const char *of_get_model(void);
@@ -547,6 +553,18 @@ static inline int of_modalias_node(struct device_node *node, char *modalias,
{
return -ENOSYS;
}
+
+static inline int of_platform_populate(struct device_node *root,
+ const struct of_device_id *matches,
+ struct device_d *parent)
+{
+ return -ENOSYS;
+}
+
+static inline struct device_d *of_find_device_by_node(struct device_node *np)
+{
+ return NULL;
+}
#endif
#define for_each_node_by_name(dn, name) \
--
1.7.2.5
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