manager.c

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/*
 * manager.c - Resource Management, Conflict Resolution, Activation and Disabling of Devices
 *
 * based on isapnp.c resource management (c) Jaroslav Kysela <[email protected]>
 * Copyright 2003 Adam Belay <[email protected]>
 * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
 *  Bjorn Helgaas <[email protected]>
 */

#include <linux/errno.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/pnp.h>
#include <linux/bitmap.h>
#include <linux/mutex.h>
#include "base.h"

DEFINE_MUTEX(pnp_res_mutex);

static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
{
    struct resource *res, local_res;

    res = pnp_get_resource(dev, IORESOURCE_IO, idx);
    if (res) {
        pnp_dbg(&dev->dev, "  io %d already set to %#llx-%#llx "
            "flags %#lx\n", idx, (unsigned long long) res->start,
            (unsigned long long) res->end, res->flags);
        return 0;
    }

    res = &local_res;
    res->flags = rule->flags | IORESOURCE_AUTO;
    res->start = 0;
    res->end = 0;

    if (!rule->size) {
        res->flags |= IORESOURCE_DISABLED;
        pnp_dbg(&dev->dev, "  io %d disabled\n", idx);
        goto __add;
    }

    res->start = rule->min;
    res->end = res->start + rule->size - 1;

    while (!pnp_check_port(dev, res)) {
        res->start += rule->align;
        res->end = res->start + rule->size - 1;
        if (res->start > rule->max || !rule->align) {
            pnp_dbg(&dev->dev, "  couldn't assign io %d "
                "(min %#llx max %#llx)\n", idx,
                (unsigned long long) rule->min,
                (unsigned long long) rule->max);
            return -EBUSY;
        }
    }

__add:
    pnp_add_io_resource(dev, res->start, res->end, res->flags);
    return 0;
}

static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
{
    struct resource *res, local_res;

    res = pnp_get_resource(dev, IORESOURCE_MEM, idx);
    if (res) {
        pnp_dbg(&dev->dev, "  mem %d already set to %#llx-%#llx "
            "flags %#lx\n", idx, (unsigned long long) res->start,
            (unsigned long long) res->end, res->flags);
        return 0;
    }

    res = &local_res;
    res->flags = rule->flags | IORESOURCE_AUTO;
    res->start = 0;
    res->end = 0;

    if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
        res->flags |= IORESOURCE_READONLY;
    if (rule->flags & IORESOURCE_MEM_CACHEABLE)
        res->flags |= IORESOURCE_CACHEABLE;
    if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
        res->flags |= IORESOURCE_RANGELENGTH;
    if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
        res->flags |= IORESOURCE_SHADOWABLE;

    if (!rule->size) {
        res->flags |= IORESOURCE_DISABLED;
        pnp_dbg(&dev->dev, "  mem %d disabled\n", idx);
        goto __add;
    }

    res->start = rule->min;
    res->end = res->start + rule->size - 1;

    while (!pnp_check_mem(dev, res)) {
        res->start += rule->align;
        res->end = res->start + rule->size - 1;
        if (res->start > rule->max || !rule->align) {
            pnp_dbg(&dev->dev, "  couldn't assign mem %d "
                "(min %#llx max %#llx)\n", idx,
                (unsigned long long) rule->min,
                (unsigned long long) rule->max);
            return -EBUSY;
        }
    }

__add:
    pnp_add_mem_resource(dev, res->start, res->end, res->flags);
    return 0;
}

static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
{
    struct resource *res, local_res;
    int i;

    /* IRQ priority: this table is good for i386 */
    static unsigned short xtab[16] = {
        5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
    };

    res = pnp_get_resource(dev, IORESOURCE_IRQ, idx);
    if (res) {
        pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
            idx, (int) res->start, res->flags);
        return 0;
    }

    res = &local_res;
    res->flags = rule->flags | IORESOURCE_AUTO;
    res->start = -1;
    res->end = -1;

    if (bitmap_empty(rule->map.bits, PNP_IRQ_NR)) {
        res->flags |= IORESOURCE_DISABLED;
        pnp_dbg(&dev->dev, "  irq %d disabled\n", idx);
        goto __add;
    }

    /* TBD: need check for >16 IRQ */
    res->start = find_next_bit(rule->map.bits, PNP_IRQ_NR, 16);
    if (res->start < PNP_IRQ_NR) {
        res->end = res->start;
        goto __add;
    }
    for (i = 0; i < 16; i++) {
        if (test_bit(xtab[i], rule->map.bits)) {
            res->start = res->end = xtab[i];
            if (pnp_check_irq(dev, res))
                goto __add;
        }
    }

    if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
        res->start = -1;
        res->end = -1;
        res->flags |= IORESOURCE_DISABLED;
        pnp_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
        goto __add;
    }

    pnp_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
    return -EBUSY;

__add:
    pnp_add_irq_resource(dev, res->start, res->flags);
    return 0;
}

#ifdef CONFIG_ISA_DMA_API
static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
{
    struct resource *res, local_res;
    int i;

    /* DMA priority: this table is good for i386 */
    static unsigned short xtab[8] = {
        1, 3, 5, 6, 7, 0, 2, 4
    };

    res = pnp_get_resource(dev, IORESOURCE_DMA, idx);
    if (res) {
        pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
            idx, (int) res->start, res->flags);
        return 0;
    }

    res = &local_res;
    res->flags = rule->flags | IORESOURCE_AUTO;
    res->start = -1;
    res->end = -1;

    for (i = 0; i < 8; i++) {
        if (rule->map & (1 << xtab[i])) {
            res->start = res->end = xtab[i];
            if (pnp_check_dma(dev, res))
                goto __add;
        }
    }
#ifdef MAX_DMA_CHANNELS
    res->start = res->end = MAX_DMA_CHANNELS;
#endif
    res->flags |= IORESOURCE_DISABLED;
    pnp_dbg(&dev->dev, "  disable dma %d\n", idx);

__add:
    pnp_add_dma_resource(dev, res->start, res->flags);
    return 0;
}
#endif /* CONFIG_ISA_DMA_API */

void pnp_init_resources(struct pnp_dev *dev)
{
    pnp_free_resources(dev);
}

static void pnp_clean_resource_table(struct pnp_dev *dev)
{
    struct pnp_resource *pnp_res, *tmp;

    list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
        if (pnp_res->res.flags & IORESOURCE_AUTO)
            pnp_free_resource(pnp_res);
    }
}

static int pnp_assign_resources(struct pnp_dev *dev, int set)
{
    struct pnp_option *option;
    int nport = 0, nmem = 0, nirq = 0;
    int ndma __maybe_unused = 0;
    int ret = 0;

    pnp_dbg(&dev->dev, "pnp_assign_resources, try dependent set %d\n", set);
    mutex_lock(&pnp_res_mutex);
    pnp_clean_resource_table(dev);

    list_for_each_entry(option, &dev->options, list) {
        if (pnp_option_is_dependent(option) &&
            pnp_option_set(option) != set)
                continue;

        switch (option->type) {
        case IORESOURCE_IO:
            ret = pnp_assign_port(dev, &option->u.port, nport++);
            break;
        case IORESOURCE_MEM:
            ret = pnp_assign_mem(dev, &option->u.mem, nmem++);
            break;
        case IORESOURCE_IRQ:
            ret = pnp_assign_irq(dev, &option->u.irq, nirq++);
            break;
#ifdef CONFIG_ISA_DMA_API
        case IORESOURCE_DMA:
            ret = pnp_assign_dma(dev, &option->u.dma, ndma++);
            break;
#endif
        default:
            ret = -EINVAL;
            break;
        }
        if (ret < 0)
            break;
    }

    mutex_unlock(&pnp_res_mutex);
    if (ret < 0) {
        pnp_dbg(&dev->dev, "pnp_assign_resources failed (%d)\n", ret);
        pnp_clean_resource_table(dev);
    } else
        dbg_pnp_show_resources(dev, "pnp_assign_resources succeeded");
    return ret;
}

int pnp_auto_config_dev(struct pnp_dev *dev)
{
    int i, ret;

    if (!pnp_can_configure(dev)) {
        pnp_dbg(&dev->dev, "configuration not supported\n");
        return -ENODEV;
    }

    ret = pnp_assign_resources(dev, 0);
    if (ret == 0)
        return 0;

    for (i = 1; i < dev->num_dependent_sets; i++) {
        ret = pnp_assign_resources(dev, i);
        if (ret == 0)
            return 0;
    }

    dev_err(&dev->dev, "unable to assign resources\n");
    return ret;
}

int pnp_start_dev(struct pnp_dev *dev)
{
    if (!pnp_can_write(dev)) {
        pnp_dbg(&dev->dev, "activation not supported\n");
        return -EINVAL;
    }

    dbg_pnp_show_resources(dev, "pnp_start_dev");
    if (dev->protocol->set(dev) < 0) {
        dev_err(&dev->dev, "activation failed\n");
        return -EIO;
    }

    dev_info(&dev->dev, "activated\n");
    return 0;
}

int pnp_stop_dev(struct pnp_dev *dev)
{
    if (!pnp_can_disable(dev)) {
        pnp_dbg(&dev->dev, "disabling not supported\n");
        return -EINVAL;
    }
    if (dev->protocol->disable(dev) < 0) {
        dev_err(&dev->dev, "disable failed\n");
        return -EIO;
    }

    dev_info(&dev->dev, "disabled\n");
    return 0;
}

int pnp_activate_dev(struct pnp_dev *dev)
{
    int error;

    if (dev->active)
        return 0;

    /* ensure resources are allocated */
    if (pnp_auto_config_dev(dev))
        return -EBUSY;

    error = pnp_start_dev(dev);
    if (error)
        return error;

    dev->active = 1;
    return 0;
}

int pnp_disable_dev(struct pnp_dev *dev)
{
    int error;

    if (!dev->active)
        return 0;

    error = pnp_stop_dev(dev);
    if (error)
        return error;

    dev->active = 0;

    /* release the resources so that other devices can use them */
    mutex_lock(&pnp_res_mutex);
    pnp_clean_resource_table(dev);
    mutex_unlock(&pnp_res_mutex);

    return 0;
}

EXPORT_SYMBOL(pnp_start_dev);
EXPORT_SYMBOL(pnp_stop_dev);
EXPORT_SYMBOL(pnp_activate_dev);
EXPORT_SYMBOL(pnp_disable_dev);