linux/drivers/mfd/mfd-core.c
Johan Hovold a77c50b44c mfd: core: Fix platform-device name collisions
Since commit 6e3f62f079 ("mfd: core: Fix platform-device id
generation") we honour PLATFORM_DEVID_AUTO and PLATFORM_DEVID_NONE when
registering mfd-devices.

Unfortunately, some mfd-drivers rely on the old behaviour of generating
platform-device ids by adding the cell id also to the special value of
PLATFORM_DEVID_NONE. The resulting platform ids are not only used to
generate device-unique names, but are also used instead of the cell id
to identify cells when probing subdevices.

These drivers should be updated to use PLATFORM_DEVID_AUTO, which would
also allow more than one device to be registered without resorting to
hacks (see for example wm831x), but lets fix the regression first by
partially reverting the above mentioned commit with respect to
PLATFORM_DEVID_NONE.

Fixes: 6e3f62f079 ("mfd: core: Fix platform-device id generation")
Cc: stable <stable@vger.kernel.org>	# v3.19
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-03-30 08:19:57 +01:00

341 lines
8.1 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>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <linux/regulator/consumer.h>
static struct device_type mfd_dev_type = {
.name = "mfd_device",
};
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,
atomic_t *usage_count)
{
if (!cell)
return 0;
pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
if (!pdev->mfd_cell)
return -ENOMEM;
pdev->mfd_cell->usage_count = usage_count;
return 0;
}
#if IS_ENABLED(CONFIG_ACPI)
static void mfd_acpi_add_device(const struct mfd_cell *cell,
struct platform_device *pdev)
{
struct acpi_device *parent_adev;
struct acpi_device *adev;
parent_adev = ACPI_COMPANION(pdev->dev.parent);
if (!parent_adev)
return;
/*
* MFD child device gets its ACPI handle either from the ACPI
* device directly under the parent that matches the acpi_pnpid or
* it will use the parent handle if is no acpi_pnpid is given.
*/
adev = parent_adev;
if (cell->acpi_pnpid) {
struct acpi_device_id ids[2] = {};
struct acpi_device *child_adev;
strlcpy(ids[0].id, cell->acpi_pnpid, sizeof(ids[0].id));
list_for_each_entry(child_adev, &parent_adev->children, node)
if (acpi_match_device_ids(child_adev, ids)) {
adev = child_adev;
break;
}
}
ACPI_COMPANION_SET(&pdev->dev, adev);
}
#else
static inline void mfd_acpi_add_device(const struct mfd_cell *cell,
struct platform_device *pdev)
{
}
#endif
static int mfd_add_device(struct device *parent, int id,
const struct mfd_cell *cell, atomic_t *usage_count,
struct resource *mem_base,
int irq_base, struct irq_domain *domain)
{
struct resource *res;
struct platform_device *pdev;
struct device_node *np = NULL;
int ret = -ENOMEM;
int platform_id;
int r;
if (id == PLATFORM_DEVID_AUTO)
platform_id = id;
else
platform_id = id + cell->id;
pdev = platform_device_alloc(cell->name, platform_id);
if (!pdev)
goto fail_alloc;
res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL);
if (!res)
goto fail_device;
pdev->dev.parent = parent;
pdev->dev.type = &mfd_dev_type;
pdev->dev.dma_mask = parent->dma_mask;
pdev->dev.dma_parms = parent->dma_parms;
pdev->dev.coherent_dma_mask = parent->coherent_dma_mask;
ret = regulator_bulk_register_supply_alias(
&pdev->dev, cell->parent_supplies,
parent, cell->parent_supplies,
cell->num_parent_supplies);
if (ret < 0)
goto fail_res;
if (parent->of_node && cell->of_compatible) {
for_each_child_of_node(parent->of_node, np) {
if (of_device_is_compatible(np, cell->of_compatible)) {
pdev->dev.of_node = np;
break;
}
}
}
mfd_acpi_add_device(cell, pdev);
if (cell->pdata_size) {
ret = platform_device_add_data(pdev,
cell->platform_data, cell->pdata_size);
if (ret)
goto fail_alias;
}
ret = mfd_platform_add_cell(pdev, cell, usage_count);
if (ret)
goto fail_alias;
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) {
if (domain) {
/* Unable to create mappings for IRQ ranges. */
WARN_ON(cell->resources[r].start !=
cell->resources[r].end);
res[r].start = res[r].end = irq_create_mapping(
domain, cell->resources[r].start);
} else {
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_alias;
}
}
ret = platform_device_add_resources(pdev, res, cell->num_resources);
if (ret)
goto fail_alias;
ret = platform_device_add(pdev);
if (ret)
goto fail_alias;
if (cell->pm_runtime_no_callbacks)
pm_runtime_no_callbacks(&pdev->dev);
kfree(res);
return 0;
fail_alias:
regulator_bulk_unregister_supply_alias(&pdev->dev,
cell->parent_supplies,
cell->num_parent_supplies);
fail_res:
kfree(res);
fail_device:
platform_device_put(pdev);
fail_alloc:
return ret;
}
int mfd_add_devices(struct device *parent, int id,
const struct mfd_cell *cells, int n_devs,
struct resource *mem_base,
int irq_base, struct irq_domain *domain)
{
int i;
int ret;
atomic_t *cnts;
/* initialize reference counting for all cells */
cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL);
if (!cnts)
return -ENOMEM;
for (i = 0; i < n_devs; i++) {
atomic_set(&cnts[i], 0);
ret = mfd_add_device(parent, id, cells + i, cnts + i, mem_base,
irq_base, domain);
if (ret)
goto fail;
}
return 0;
fail:
if (i)
mfd_remove_devices(parent);
else
kfree(cnts);
return ret;
}
EXPORT_SYMBOL(mfd_add_devices);
static int mfd_remove_devices_fn(struct device *dev, void *c)
{
struct platform_device *pdev;
const struct mfd_cell *cell;
atomic_t **usage_count = c;
if (dev->type != &mfd_dev_type)
return 0;
pdev = to_platform_device(dev);
cell = mfd_get_cell(pdev);
regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
cell->num_parent_supplies);
/* 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,
cell_entry.usage_count, NULL, 0, NULL))
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");