diff options
Diffstat (limited to 'drivers/of/platform.c')
-rw-r--r-- | drivers/of/platform.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/of/platform.c b/drivers/of/platform.c new file mode 100644 index 00000000..343ad29e --- /dev/null +++ b/drivers/of/platform.c @@ -0,0 +1,465 @@ +/* + * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp. + * <benh@kernel.crashing.org> + * and Arnd Bergmann, IBM Corp. + * Merged from powerpc/kernel/of_platform.c and + * sparc{,64}/kernel/of_device.c by Stephen Rothwell + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/amba/bus.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/slab.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +const struct of_device_id of_default_bus_match_table[] = { + { .compatible = "simple-bus", }, +#ifdef CONFIG_ARM_AMBA + { .compatible = "arm,amba-bus", }, +#endif /* CONFIG_ARM_AMBA */ + {} /* Empty terminated list */ +}; + +static int of_dev_node_match(struct device *dev, void *data) +{ + return dev->of_node == data; +} + +/** + * 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 platform_device *of_find_device_by_node(struct device_node *np) +{ + struct device *dev; + + dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match); + return dev ? to_platform_device(dev) : NULL; +} +EXPORT_SYMBOL(of_find_device_by_node); + +#if defined(CONFIG_PPC_DCR) +#include <asm/dcr.h> +#endif + +#ifdef CONFIG_OF_ADDRESS +/* + * The following routines scan a subtree and registers a device for + * each applicable node. + * + * Note: sparc doesn't use these routines because it has a different + * mechanism for creating devices from device tree nodes. + */ + +/** + * 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. + */ +void of_device_make_bus_id(struct device *dev) +{ + static atomic_t bus_no_reg_magic; + struct device_node *node = dev->of_node; + const u32 *reg; + u64 addr; + int magic; + +#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(node, "dcr-reg", NULL); + if (reg) { +#ifdef CONFIG_PPC_DCR_NATIVE + dev_set_name(dev, "d%x.%s", *reg, node->name); +#else /* CONFIG_PPC_DCR_NATIVE */ + u64 addr = of_translate_dcr_address(node, *reg, NULL); + if (addr != OF_BAD_ADDR) { + dev_set_name(dev, "D%llx.%s", + (unsigned long long)addr, node->name); + return; + } +#endif /* !CONFIG_PPC_DCR_NATIVE */ + } +#endif /* CONFIG_PPC_DCR */ + + /* + * For MMIO, get the physical address + */ + reg = of_get_property(node, "reg", NULL); + if (reg) { + addr = of_translate_address(node, reg); + if (addr != OF_BAD_ADDR) { + dev_set_name(dev, "%llx.%s", + (unsigned long long)addr, node->name); + return; + } + } + + /* + * No BusID, use the node name and add a globally incremented + * counter (and pray...) + */ + magic = atomic_add_return(1, &bus_no_reg_magic); + dev_set_name(dev, "%s.%d", node->name, magic - 1); +} + +/** + * of_device_alloc - Allocate and initialize an of_device + * @np: device node to assign to device + * @bus_id: Name to assign to the device. May be null to use default name. + * @parent: Parent device. + */ +struct platform_device *of_device_alloc(struct device_node *np, + const char *bus_id, + struct device *parent) +{ + struct platform_device *dev; + int rc, i, num_reg = 0, num_irq; + struct resource *res, temp_res; + + dev = platform_device_alloc("", -1); + if (!dev) + return NULL; + + /* count the io and irq resources */ + while (of_address_to_resource(np, num_reg, &temp_res) == 0) + num_reg++; + num_irq = of_irq_count(np); + + /* Populate the resource table */ + if (num_irq || num_reg) { + res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL); + if (!res) { + platform_device_put(dev); + return NULL; + } + + dev->num_resources = num_reg + num_irq; + dev->resource = res; + for (i = 0; i < num_reg; i++, res++) { + rc = of_address_to_resource(np, i, res); + WARN_ON(rc); + } + WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq); + } + + dev->dev.of_node = of_node_get(np); +#if defined(CONFIG_MICROBLAZE) + dev->dev.dma_mask = &dev->archdata.dma_mask; +#endif + dev->dev.parent = parent; + + if (bus_id) + dev_set_name(&dev->dev, "%s", bus_id); + else + of_device_make_bus_id(&dev->dev); + + return dev; +} +EXPORT_SYMBOL(of_device_alloc); + +/** + * of_platform_device_create_pdata - Alloc, initialize and register an of_device + * @np: pointer to node to create device for + * @bus_id: name to assign device + * @platform_data: pointer to populate platform_data pointer with + * @parent: Linux device model parent device. + * + * Returns pointer to created platform device, or NULL if a device was not + * registered. Unavailable devices will not get registered. + */ +struct platform_device *of_platform_device_create_pdata( + struct device_node *np, + const char *bus_id, + void *platform_data, + struct device *parent) +{ + struct platform_device *dev; + + if (!of_device_is_available(np)) + return NULL; + + dev = of_device_alloc(np, bus_id, parent); + if (!dev) + return NULL; + +#if defined(CONFIG_MICROBLAZE) + dev->archdata.dma_mask = 0xffffffffUL; +#endif + dev->dev.coherent_dma_mask = DMA_BIT_MASK(32); + dev->dev.bus = &platform_bus_type; + dev->dev.platform_data = platform_data; + + /* We do not fill the DMA ops for platform devices by default. + * This is currently the responsibility of the platform code + * to do such, possibly using a device notifier + */ + + if (of_device_add(dev) != 0) { + platform_device_put(dev); + return NULL; + } + + return dev; +} + +/** + * of_platform_device_create - Alloc, initialize and register an of_device + * @np: pointer to node to create device for + * @bus_id: name to assign device + * @parent: Linux device model parent device. + * + * Returns pointer to created platform device, or NULL if a device was not + * registered. Unavailable devices will not get registered. + */ +struct platform_device *of_platform_device_create(struct device_node *np, + const char *bus_id, + struct device *parent) +{ + return of_platform_device_create_pdata(np, bus_id, NULL, parent); +} +EXPORT_SYMBOL(of_platform_device_create); + +#ifdef CONFIG_ARM_AMBA +static struct amba_device *of_amba_device_create(struct device_node *node, + const char *bus_id, + void *platform_data, + struct device *parent) +{ + struct amba_device *dev; + const void *prop; + int i, ret; + + pr_debug("Creating amba device %s\n", node->full_name); + + if (!of_device_is_available(node)) + return NULL; + + dev = amba_device_alloc(NULL, 0, 0); + if (!dev) + return NULL; + + /* setup generic device info */ + dev->dev.coherent_dma_mask = ~0; + dev->dev.of_node = of_node_get(node); + dev->dev.parent = parent; + dev->dev.platform_data = platform_data; + if (bus_id) + dev_set_name(&dev->dev, "%s", bus_id); + else + of_device_make_bus_id(&dev->dev); + + /* setup amba-specific device info */ + dev->dma_mask = ~0; + + /* Allow the HW Peripheral ID to be overridden */ + prop = of_get_property(node, "arm,primecell-periphid", NULL); + if (prop) + dev->periphid = of_read_ulong(prop, 1); + + /* Decode the IRQs and address ranges */ + for (i = 0; i < AMBA_NR_IRQS; i++) + dev->irq[i] = irq_of_parse_and_map(node, i); + + ret = of_address_to_resource(node, 0, &dev->res); + if (ret) + goto err_free; + + ret = amba_device_add(dev, &iomem_resource); + if (ret) + goto err_free; + + return dev; + +err_free: + amba_device_put(dev); + return NULL; +} +#else /* CONFIG_ARM_AMBA */ +static struct amba_device *of_amba_device_create(struct device_node *node, + const char *bus_id, + void *platform_data, + struct device *parent) +{ + return NULL; +} +#endif /* CONFIG_ARM_AMBA */ + +/** + * of_devname_lookup() - Given a device node, lookup the preferred Linux name + */ +static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup, + struct device_node *np) +{ + struct resource res; + + if (!lookup) + return NULL; + + for(; lookup->compatible != NULL; lookup++) { + if (!of_device_is_compatible(np, lookup->compatible)) + continue; + if (of_address_to_resource(np, 0, &res)) + continue; + if (res.start != lookup->phys_addr) + continue; + pr_debug("%s: devname=%s\n", np->full_name, lookup->name); + return lookup; + } + + return NULL; +} + +/** + * 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 + * @lookup: auxdata table for matching id and platform_data with device nodes + * @parent: parent for new device, or NULL for top level. + * @strict: require compatible property + * + * 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, + const struct of_dev_auxdata *lookup, + struct device *parent, bool strict) +{ + const struct of_dev_auxdata *auxdata; + struct device_node *child; + struct platform_device *dev; + const char *bus_id = NULL; + void *platform_data = NULL; + int rc = 0; + + /* Make sure it has a compatible property */ + if (strict && (!of_get_property(bus, "compatible", NULL))) { + pr_debug("%s() - skipping %s, no compatible prop\n", + __func__, bus->full_name); + return 0; + } + + auxdata = of_dev_lookup(lookup, bus); + if (auxdata) { + bus_id = auxdata->name; + platform_data = auxdata->platform_data; + } + + if (of_device_is_compatible(bus, "arm,primecell")) { + of_amba_device_create(bus, bus_id, platform_data, parent); + return 0; + } + + dev = of_platform_device_create_pdata(bus, bus_id, platform_data, 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, lookup, &dev->dev, strict); + if (rc) { + of_node_put(child); + break; + } + } + return rc; +} + +/** + * of_platform_bus_probe() - Probe the device-tree for platform buses + * @root: parent of the first level to probe or NULL for the root of the tree + * @matches: match table for bus nodes + * @parent: parent to hook devices from, NULL for toplevel + * + * Note that children of the provided root are not instantiated as devices + * unless the specified root itself matches the bus list and is not NULL. + */ +int of_platform_bus_probe(struct device_node *root, + const struct of_device_id *matches, + struct device *parent) +{ + struct device_node *child; + int rc = 0; + + root = root ? of_node_get(root) : of_find_node_by_path("/"); + if (!root) + return -EINVAL; + + pr_debug("of_platform_bus_probe()\n"); + pr_debug(" starting at: %s\n", root->full_name); + + /* Do a self check of bus type, if there's a match, create children */ + if (of_match_node(matches, root)) { + rc = of_platform_bus_create(root, matches, NULL, parent, false); + } else for_each_child_of_node(root, child) { + if (!of_match_node(matches, child)) + continue; + rc = of_platform_bus_create(child, matches, NULL, parent, false); + if (rc) + break; + } + + of_node_put(root); + return rc; +} +EXPORT_SYMBOL(of_platform_bus_probe); + +/** + * 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 + * + * Similar to of_platform_bus_probe(), this function walks the device tree + * and creates devices from nodes. It differs in that it follows the modern + * convention of requiring all device nodes to have a 'compatible' property, + * and it is suitable for creating devices which are children of the root + * node (of_platform_bus_probe will only create children of the root which + * are selected by the @matches argument). + * + * New board support should be using this function instead of + * of_platform_bus_probe(). + * + * Returns 0 on success, < 0 on failure. + */ +int of_platform_populate(struct device_node *root, + const struct of_device_id *matches, + const struct of_dev_auxdata *lookup, + struct device *parent) +{ + struct device_node *child; + int rc = 0; + + root = root ? of_node_get(root) : of_find_node_by_path("/"); + if (!root) + return -EINVAL; + + for_each_child_of_node(root, child) { + rc = of_platform_bus_create(child, matches, lookup, parent, true); + if (rc) + break; + } + + of_node_put(root); + return rc; +} +#endif /* CONFIG_OF_ADDRESS */ |