u-boot/drivers/core/uclass.c
Simon Glass 3346c87625 dm: Improve handling of a missing uclass
When a uclass definition is missing, no drivers in that uclass can operate.
This can happen if a board has a strange collection of options (e.g. the
driver is enabled but the uclass is not).

Unfortunately this is very confusing at present. Starting up driver model
results in a -ENOENT error, which is pretty generic. Quite a big of digging
is needed to get to the root cause.

To help with this, change the error to a very strange one with no other
users in U-Boot. Also add a debug message.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-09-02 21:28:23 -06:00

545 lines
10 KiB
C

/*
* Copyright (c) 2013 Google, Inc
*
* (C) Copyright 2012
* Pavel Herrmann <morpheus.ibis@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <errno.h>
#include <malloc.h>
#include <dm/device.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/uclass.h>
#include <dm/uclass-internal.h>
#include <dm/util.h>
DECLARE_GLOBAL_DATA_PTR;
struct uclass *uclass_find(enum uclass_id key)
{
struct uclass *uc;
if (!gd->dm_root)
return NULL;
/*
* TODO(sjg@chromium.org): Optimise this, perhaps moving the found
* node to the start of the list, or creating a linear array mapping
* id to node.
*/
list_for_each_entry(uc, &gd->uclass_root, sibling_node) {
if (uc->uc_drv->id == key)
return uc;
}
return NULL;
}
/**
* uclass_add() - Create new uclass in list
* @id: Id number to create
* @ucp: Returns pointer to uclass, or NULL on error
* @return 0 on success, -ve on error
*
* The new uclass is added to the list. There must be only one uclass for
* each id.
*/
static int uclass_add(enum uclass_id id, struct uclass **ucp)
{
struct uclass_driver *uc_drv;
struct uclass *uc;
int ret;
*ucp = NULL;
uc_drv = lists_uclass_lookup(id);
if (!uc_drv) {
debug("Cannot find uclass for id %d: please add the UCLASS_DRIVER() declaration for this UCLASS_... id\n",
id);
/*
* Use a strange error to make this case easier to find. When
* a uclass is not available it can prevent driver model from
* starting up and this failure is otherwise hard to debug.
*/
return -EPFNOSUPPORT;
}
uc = calloc(1, sizeof(*uc));
if (!uc)
return -ENOMEM;
if (uc_drv->priv_auto_alloc_size) {
uc->priv = calloc(1, uc_drv->priv_auto_alloc_size);
if (!uc->priv) {
ret = -ENOMEM;
goto fail_mem;
}
}
uc->uc_drv = uc_drv;
INIT_LIST_HEAD(&uc->sibling_node);
INIT_LIST_HEAD(&uc->dev_head);
list_add(&uc->sibling_node, &DM_UCLASS_ROOT_NON_CONST);
if (uc_drv->init) {
ret = uc_drv->init(uc);
if (ret)
goto fail;
}
*ucp = uc;
return 0;
fail:
if (uc_drv->priv_auto_alloc_size) {
free(uc->priv);
uc->priv = NULL;
}
list_del(&uc->sibling_node);
fail_mem:
free(uc);
return ret;
}
int uclass_destroy(struct uclass *uc)
{
struct uclass_driver *uc_drv;
struct udevice *dev;
int ret;
/*
* We cannot use list_for_each_entry_safe() here. If a device in this
* uclass has a child device also in this uclass, it will be also be
* unbound (by the recursion in the call to device_unbind() below).
* We can loop until the list is empty.
*/
while (!list_empty(&uc->dev_head)) {
dev = list_first_entry(&uc->dev_head, struct udevice,
uclass_node);
ret = device_remove(dev);
if (ret)
return ret;
ret = device_unbind(dev);
if (ret)
return ret;
}
uc_drv = uc->uc_drv;
if (uc_drv->destroy)
uc_drv->destroy(uc);
list_del(&uc->sibling_node);
if (uc_drv->priv_auto_alloc_size)
free(uc->priv);
free(uc);
return 0;
}
int uclass_get(enum uclass_id id, struct uclass **ucp)
{
struct uclass *uc;
*ucp = NULL;
uc = uclass_find(id);
if (!uc)
return uclass_add(id, ucp);
*ucp = uc;
return 0;
}
int uclass_find_device(enum uclass_id id, int index, struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
if (list_empty(&uc->dev_head))
return -ENODEV;
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
if (!index--) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_find_first_device(enum uclass_id id, struct udevice **devp)
{
struct uclass *uc;
int ret;
*devp = NULL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
if (list_empty(&uc->dev_head))
return 0;
*devp = list_first_entry(&uc->dev_head, struct udevice, uclass_node);
return 0;
}
int uclass_find_next_device(struct udevice **devp)
{
struct udevice *dev = *devp;
*devp = NULL;
if (list_is_last(&dev->uclass_node, &dev->uclass->dev_head))
return 0;
*devp = list_entry(dev->uclass_node.next, struct udevice, uclass_node);
return 0;
}
int uclass_find_device_by_name(enum uclass_id id, const char *name,
struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
if (!name)
return -EINVAL;
ret = uclass_get(id, &uc);
if (ret)
return ret;
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
if (!strncmp(dev->name, name, strlen(name))) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_find_device_by_seq(enum uclass_id id, int seq_or_req_seq,
bool find_req_seq, struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
debug("%s: %d %d\n", __func__, find_req_seq, seq_or_req_seq);
if (seq_or_req_seq == -1)
return -ENODEV;
ret = uclass_get(id, &uc);
if (ret)
return ret;
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
debug(" - %d %d\n", dev->req_seq, dev->seq);
if ((find_req_seq ? dev->req_seq : dev->seq) ==
seq_or_req_seq) {
*devp = dev;
debug(" - found\n");
return 0;
}
}
debug(" - not found\n");
return -ENODEV;
}
static int uclass_find_device_by_of_offset(enum uclass_id id, int node,
struct udevice **devp)
{
struct uclass *uc;
struct udevice *dev;
int ret;
*devp = NULL;
if (node < 0)
return -ENODEV;
ret = uclass_get(id, &uc);
if (ret)
return ret;
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
if (dev->of_offset == node) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
static int uclass_find_device_by_phandle(enum uclass_id id,
struct udevice *parent,
const char *name,
struct udevice **devp)
{
struct udevice *dev;
struct uclass *uc;
int find_phandle;
int ret;
*devp = NULL;
find_phandle = fdtdec_get_int(gd->fdt_blob, parent->of_offset, name,
-1);
if (find_phandle <= 0)
return -ENOENT;
ret = uclass_get(id, &uc);
if (ret)
return ret;
list_for_each_entry(dev, &uc->dev_head, uclass_node) {
uint phandle = fdt_get_phandle(gd->fdt_blob, dev->of_offset);
if (phandle == find_phandle) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int uclass_get_device_tail(struct udevice *dev, int ret,
struct udevice **devp)
{
if (ret)
return ret;
assert(dev);
ret = device_probe(dev);
if (ret)
return ret;
*devp = dev;
return 0;
}
int uclass_get_device(enum uclass_id id, int index, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device(id, index, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_name(enum uclass_id id, const char *name,
struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_name(id, name, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_seq(enum uclass_id id, int seq, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_seq(id, seq, false, &dev);
if (ret == -ENODEV) {
/*
* We didn't find it in probed devices. See if there is one
* that will request this seq if probed.
*/
ret = uclass_find_device_by_seq(id, seq, true, &dev);
}
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_of_offset(enum uclass_id id, int node,
struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_of_offset(id, node, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
const char *name, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_device_by_phandle(id, parent, name, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_first_device(enum uclass_id id, struct udevice **devp)
{
struct udevice *dev;
int ret;
*devp = NULL;
ret = uclass_find_first_device(id, &dev);
if (!dev)
return 0;
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_next_device(struct udevice **devp)
{
struct udevice *dev = *devp;
int ret;
*devp = NULL;
ret = uclass_find_next_device(&dev);
if (!dev)
return 0;
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_bind_device(struct udevice *dev)
{
struct uclass *uc;
int ret;
uc = dev->uclass;
list_add_tail(&dev->uclass_node, &uc->dev_head);
if (dev->parent) {
struct uclass_driver *uc_drv = dev->parent->uclass->uc_drv;
if (uc_drv->child_post_bind) {
ret = uc_drv->child_post_bind(dev);
if (ret)
goto err;
}
}
if (uc->uc_drv->post_bind) {
ret = uc->uc_drv->post_bind(dev);
if (ret)
goto err;
}
return 0;
err:
/* There is no need to undo the parent's post_bind call */
list_del(&dev->uclass_node);
return ret;
}
#if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
int uclass_unbind_device(struct udevice *dev)
{
struct uclass *uc;
int ret;
uc = dev->uclass;
if (uc->uc_drv->pre_unbind) {
ret = uc->uc_drv->pre_unbind(dev);
if (ret)
return ret;
}
list_del(&dev->uclass_node);
return 0;
}
#endif
int uclass_resolve_seq(struct udevice *dev)
{
struct udevice *dup;
int seq;
int ret;
assert(dev->seq == -1);
ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, dev->req_seq,
false, &dup);
if (!ret) {
dm_warn("Device '%s': seq %d is in use by '%s'\n",
dev->name, dev->req_seq, dup->name);
} else if (ret == -ENODEV) {
/* Our requested sequence number is available */
if (dev->req_seq != -1)
return dev->req_seq;
} else {
return ret;
}
for (seq = 0; seq < DM_MAX_SEQ; seq++) {
ret = uclass_find_device_by_seq(dev->uclass->uc_drv->id, seq,
false, &dup);
if (ret == -ENODEV)
break;
if (ret)
return ret;
}
return seq;
}
int uclass_pre_probe_device(struct udevice *dev)
{
struct uclass_driver *uc_drv;
int ret;
uc_drv = dev->uclass->uc_drv;
if (uc_drv->pre_probe) {
ret = uc_drv->pre_probe(dev);
if (ret)
return ret;
}
if (!dev->parent)
return 0;
uc_drv = dev->parent->uclass->uc_drv;
if (uc_drv->child_pre_probe)
return uc_drv->child_pre_probe(dev);
return 0;
}
int uclass_post_probe_device(struct udevice *dev)
{
struct uclass_driver *uc_drv = dev->uclass->uc_drv;
if (uc_drv->post_probe)
return uc_drv->post_probe(dev);
return 0;
}
#if CONFIG_IS_ENABLED(DM_DEVICE_REMOVE)
int uclass_pre_remove_device(struct udevice *dev)
{
struct uclass_driver *uc_drv;
struct uclass *uc;
int ret;
uc = dev->uclass;
uc_drv = uc->uc_drv;
if (uc->uc_drv->pre_remove) {
ret = uc->uc_drv->pre_remove(dev);
if (ret)
return ret;
}
if (uc_drv->per_device_auto_alloc_size) {
free(dev->uclass_priv);
dev->uclass_priv = NULL;
}
dev->seq = -1;
return 0;
}
#endif