platform.c

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/*
 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
 *           <[email protected]>
 *    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;
}

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.
 */

void of_device_make_bus_id(struct device *dev)
{
    static atomic_t bus_no_reg_magic;
    struct device_node *node = dev->of_node;
    const __be32 *reg;
    u64 addr;
    const __be32 *addrp;
    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) {
        if (of_can_translate_address(node)) {
            addr = of_translate_address(node, reg);
        } else {
            addrp = of_get_address(node, 0, NULL, NULL);
            if (addrp)
                addr = of_read_number(addrp, 1);
            else
                addr = OF_BAD_ADDR;
        }
        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);
}

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 */
    if (of_can_translate_address(np))
        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);

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;
}

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 */

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))
            if (res.start != lookup->phys_addr)
                continue;
        pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
        return lookup;
    }

    return NULL;
}

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;
}

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);

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;
}
EXPORT_SYMBOL_GPL(of_platform_populate);
#endif /* CONFIG_OF_ADDRESS */