linux/drivers/mfd/mfd-core.c
Jean Delvare 81b5482c32 mfd: Fix ACPI conflict check
The code is currently always checking the first resource of every
device only (several times.) This has been broken since the ACPI check
was added in February 2010 in commit
91fedede03.

Fix the check to run on each resource individually, once.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@vger.kernel.org
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2012-02-23 17:34:22 +01:00

238 lines
5.5 KiB
C

/*
* drivers/mfd/mfd-core.c
*
* core MFD support
* Copyright (c) 2006 Ian Molton
* Copyright (c) 2007,2008 Dmitry Baryshkov
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/acpi.h>
#include <linux/mfd/core.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/module.h>
int mfd_cell_enable(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
int err = 0;
/* only call enable hook if the cell wasn't previously enabled */
if (atomic_inc_return(cell->usage_count) == 1)
err = cell->enable(pdev);
/* if the enable hook failed, decrement counter to allow retries */
if (err)
atomic_dec(cell->usage_count);
return err;
}
EXPORT_SYMBOL(mfd_cell_enable);
int mfd_cell_disable(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
int err = 0;
/* only disable if no other clients are using it */
if (atomic_dec_return(cell->usage_count) == 0)
err = cell->disable(pdev);
/* if the disable hook failed, increment to allow retries */
if (err)
atomic_inc(cell->usage_count);
/* sanity check; did someone call disable too many times? */
WARN_ON(atomic_read(cell->usage_count) < 0);
return err;
}
EXPORT_SYMBOL(mfd_cell_disable);
static int mfd_platform_add_cell(struct platform_device *pdev,
const struct mfd_cell *cell)
{
if (!cell)
return 0;
pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
if (!pdev->mfd_cell)
return -ENOMEM;
return 0;
}
static int mfd_add_device(struct device *parent, int id,
const struct mfd_cell *cell,
struct resource *mem_base,
int irq_base)
{
struct resource *res;
struct platform_device *pdev;
int ret = -ENOMEM;
int r;
pdev = platform_device_alloc(cell->name, id + cell->id);
if (!pdev)
goto fail_alloc;
res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL);
if (!res)
goto fail_device;
pdev->dev.parent = parent;
if (cell->pdata_size) {
ret = platform_device_add_data(pdev,
cell->platform_data, cell->pdata_size);
if (ret)
goto fail_res;
}
ret = mfd_platform_add_cell(pdev, cell);
if (ret)
goto fail_res;
for (r = 0; r < cell->num_resources; r++) {
res[r].name = cell->resources[r].name;
res[r].flags = cell->resources[r].flags;
/* Find out base to use */
if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) {
res[r].parent = mem_base;
res[r].start = mem_base->start +
cell->resources[r].start;
res[r].end = mem_base->start +
cell->resources[r].end;
} else if (cell->resources[r].flags & IORESOURCE_IRQ) {
res[r].start = irq_base +
cell->resources[r].start;
res[r].end = irq_base +
cell->resources[r].end;
} else {
res[r].parent = cell->resources[r].parent;
res[r].start = cell->resources[r].start;
res[r].end = cell->resources[r].end;
}
if (!cell->ignore_resource_conflicts) {
ret = acpi_check_resource_conflict(&res[r]);
if (ret)
goto fail_res;
}
}
ret = platform_device_add_resources(pdev, res, cell->num_resources);
if (ret)
goto fail_res;
ret = platform_device_add(pdev);
if (ret)
goto fail_res;
if (cell->pm_runtime_no_callbacks)
pm_runtime_no_callbacks(&pdev->dev);
kfree(res);
return 0;
fail_res:
kfree(res);
fail_device:
platform_device_put(pdev);
fail_alloc:
return ret;
}
int mfd_add_devices(struct device *parent, int id,
struct mfd_cell *cells, int n_devs,
struct resource *mem_base,
int irq_base)
{
int i;
int ret = 0;
atomic_t *cnts;
/* initialize reference counting for all cells */
cnts = kcalloc(sizeof(*cnts), n_devs, GFP_KERNEL);
if (!cnts)
return -ENOMEM;
for (i = 0; i < n_devs; i++) {
atomic_set(&cnts[i], 0);
cells[i].usage_count = &cnts[i];
ret = mfd_add_device(parent, id, cells + i, mem_base, irq_base);
if (ret)
break;
}
if (ret)
mfd_remove_devices(parent);
return ret;
}
EXPORT_SYMBOL(mfd_add_devices);
static int mfd_remove_devices_fn(struct device *dev, void *c)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
atomic_t **usage_count = c;
/* find the base address of usage_count pointers (for freeing) */
if (!*usage_count || (cell->usage_count < *usage_count))
*usage_count = cell->usage_count;
platform_device_unregister(pdev);
return 0;
}
void mfd_remove_devices(struct device *parent)
{
atomic_t *cnts = NULL;
device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
kfree(cnts);
}
EXPORT_SYMBOL(mfd_remove_devices);
int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
{
struct mfd_cell cell_entry;
struct device *dev;
struct platform_device *pdev;
int i;
/* fetch the parent cell's device (should already be registered!) */
dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
if (!dev) {
printk(KERN_ERR "failed to find device for cell %s\n", cell);
return -ENODEV;
}
pdev = to_platform_device(dev);
memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
WARN_ON(!cell_entry.enable);
for (i = 0; i < n_clones; i++) {
cell_entry.name = clones[i];
/* don't give up if a single call fails; just report error */
if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, NULL, 0))
dev_err(dev, "failed to create platform device '%s'\n",
clones[i]);
}
return 0;
}
EXPORT_SYMBOL(mfd_clone_cell);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");