/* -*- c-basic-offset: 8 -*-
*
* fw-device.c - Device probing and sysfs code.
*
* Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/errno.h>
#include <linux/kthread.h>
#include <linux/device.h>
#include <linux/delay.h>
#include "fw-transaction.h"
#include "fw-topology.h"
#include "fw-device.h"
void fw_csr_iterator_init(struct fw_csr_iterator *ci, u32 * p)
{
ci->p = p + 1;
ci->end = ci->p + (p[0] >> 16);
}
EXPORT_SYMBOL(fw_csr_iterator_init);
int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
{
*key = *ci->p >> 24;
*value = *ci->p & 0xffffff;
return ci->p++ < ci->end;
}
EXPORT_SYMBOL(fw_csr_iterator_next);
static int is_fw_unit(struct device *dev);
static int match_unit_directory(u32 * directory, const struct fw_device_id *id)
{
struct fw_csr_iterator ci;
int key, value, match;
match = 0;
fw_csr_iterator_init(&ci, directory);
while (fw_csr_iterator_next(&ci, &key, &value)) {
if (key == CSR_VENDOR && value == id->vendor)
match |= FW_MATCH_VENDOR;
if (key == CSR_MODEL && value == id->model)
match |= FW_MATCH_MODEL;
if (key == CSR_SPECIFIER_ID && value == id->specifier_id)
match |= FW_MATCH_SPECIFIER_ID;
if (key == CSR_VERSION && value == id->version)
match |= FW_MATCH_VERSION;
}
return (match & id->match_flags) == id->match_flags;
}
static int fw_unit_match(struct device *dev, struct device_driver *drv)
{
struct fw_unit *unit = fw_unit(dev);
struct fw_driver *driver = fw_driver(drv);
int i;
/* We only allow binding to fw_units. */
if (!is_fw_unit(dev))
return 0;
for (i = 0; driver->id_table[i].match_flags != 0; i++) {
if (match_unit_directory(unit->directory, &driver->id_table[i]))
return 1;
}
return 0;
}
static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
{
struct fw_device *device = fw_device(unit->device.parent);
struct fw_csr_iterator ci;
int key, value;
int vendor = 0;
int model = 0;
int specifier_id = 0;
int version = 0;
fw_csr_iterator_init(&ci, &device->config_rom[5]);
while (fw_csr_iterator_next(&ci, &key, &value)) {
switch (key) {
case CSR_VENDOR:
vendor = value;
break;
case CSR_MODEL:
model = value;
break;
}
}
fw_csr_iterator_init(&ci, unit->directory);
while (fw_csr_iterator_next(&ci, &key, &value)) {
switch (key) {
case CSR_SPECIFIER_ID:
specifier_id = value;
break;
case CSR_VERSION:
version = value;
break;
}
}
return snprintf(buffer, buffer_size,
"ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
vendor, model, specifier_id, version);
}
static int
fw_unit_uevent(struct device *dev, char **envp, int num_envp,
char *buffer, int buffer_size)
{
struct fw_unit *unit = fw_unit(dev);
char modalias[64];
int length = 0;
int i = 0;
if (!is_fw_unit(dev))
goto out;
get_modalias(unit, modalias, sizeof modalias);
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"MODALIAS=%s", modalias))
return -ENOMEM;
out:
envp[i] = NULL;
return 0;
}
struct bus_type fw_bus_type = {
.name = "firewire",
.match = fw_unit_match,
.uevent = fw_unit_uevent,
};
EXPORT_SYMBOL(fw_bus_type);
extern struct fw_device *fw_device_get(struct fw_device *device)
{
get_device(&device->device);
return device;
}
extern void fw_device_put(struct fw_device *device)
{
put_device(&device->device);
}
static void fw_device_release(struct device *dev)
{
struct fw_device *device = fw_device(dev);
unsigned long flags;
/* Take the card lock so we don't set this to NULL while a
* FW_NODE_UPDATED callback is being handled. */
spin_lock_irqsave(&device->card->lock, flags);
device->node->data = NULL;
spin_unlock_irqrestore(&device->card->lock, flags);
fw_node_put(device->node);
fw_card_put(device->card);
kfree(device->config_rom);
kfree(device);
}
int fw_device_enable_phys_dma(struct fw_device *device)
{
return device->card->driver->enable_phys_dma(device->card,
device->node_id,
device->generation);
}
EXPORT_SYMBOL(fw_device_enable_phys_dma);
static ssize_t
show_modalias_attribute(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct fw_unit *unit = fw_unit(dev);
int length;
length = get_modalias(unit, buf, PAGE_SIZE);
strcpy(buf + length, "\n");
return length + 1;
}
static struct device_attribute modalias_attribute = {
.attr = { .name = "modalias", .mode = S_IRUGO, },
.show = show_modalias_attribute,
};
static ssize_t
show_config_rom_attribute(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct fw_device *device = fw_device(dev);
memcpy(buf, device->config_rom, device->config_rom_length * 4);
return device->config_rom_length * 4;
}
static struct device_attribute config_rom_attribute = {
.attr = {.name = "config_rom", .mode = S_IRUGO,},
.show = show_config_rom_attribute,
};
struct read_quadlet_callback_data {
struct completion done;
int rcode;
u32 data;
};
static void
complete_transaction(struct fw_card *card, int rcode,
void *payload, size_t length, void *data)
{
struct read_quadlet_callback_data *callback_data = data;
if (rcode == RCODE_COMPLETE)
callback_data->data = be32_to_cpu(*(__be32 *)payload);
callback_data->rcode = rcode;
complete(&callback_data->done);
}
static int read_rom(struct fw_device *device, int index, u32 * data)
{
struct read_quadlet_callback_data callback_data;
struct fw_transaction t;
u64 offset;
init_completion(&callback_data.done);
offset = 0xfffff0000400ULL + index * 4;
fw_send_request(device->card, &t, TCODE_READ_QUADLET_REQUEST,
device->node_id,
device->generation, SCODE_100,
offset, NULL, 4, complete_transaction, &callback_data);
wait_for_completion(&callback_data.done);
*data = callback_data.data;
return callback_data.rcode;
}
static int read_bus_info_block(struct fw_device *device)
{
static u32 rom[256];
u32 stack[16], sp, key;
int i, end, length;
/* First read the bus info block. */
for (i = 0; i < 5; i++) {
if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
return -1;
/* As per IEEE1212 7.2, during power-up, devices can
* reply with a 0 for the first quadlet of the config
* rom to indicate that they are booting (for example,
* if the firmware is on the disk of a external
* harddisk). In that case we just fail, and the
* retry mechanism will try again later. */
if (i == 0 && rom[i] == 0)
return -1;
}
/* Now parse the config rom. The config rom is a recursive
* directory structure so we parse it using a stack of
* references to the blocks that make up the structure. We
* push a reference to the root directory on the stack to
* start things off. */
length = i;
sp = 0;
stack[sp++] = 0xc0000005;
while (sp > 0) {
/* Pop the next block reference of the stack. The
* lower 24 bits is the offset into the config rom,
* the upper 8 bits are the type of the reference the
* block. */
key = stack[--sp];
i = key & 0xffffff;
if (i >= ARRAY_SIZE(rom))
/* The reference points outside the standard
* config rom area, something's fishy. */
return -1;
/* Read header quadlet for the block to get the length. */
if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
return -1;
end = i + (rom[i] >> 16) + 1;
i++;
if (end > ARRAY_SIZE(rom))
/* This block extends outside standard config
* area (and the array we're reading it
* into). That's broken, so ignore this
* device. */
return -1;
/* Now read in the block. If this is a directory
* block, check the entries as we read them to see if
* it references another block, and push it in that case. */
while (i < end) {
if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
return -1;
if ((key >> 30) == 3 && (rom[i] >> 30) > 1 &&
sp < ARRAY_SIZE(stack))
stack[sp++] = i + rom[i];
i++;
}
if (length < i)
length = i;
}
device->config_rom = kmalloc(length * 4, GFP_KERNEL);
if (device->config_rom == NULL)
return -1;
memcpy(device->config_rom, rom, length * 4);
device->config_rom_length = length;
return 0;
}
static void fw_unit_release(struct device *dev)
{
struct fw_unit *unit = fw_unit(dev);
kfree(unit);
}
static int is_fw_unit(struct device *dev)
{
return dev->release == fw_unit_release;
}
static void create_units(struct fw_device *device)
{
struct fw_csr_iterator ci;
struct fw_unit *unit;
int key, value, i;
i = 0;
fw_csr_iterator_init(&ci, &device->config_rom[5]);
while (fw_csr_iterator_next(&ci, &key, &value)) {
if (key != (CSR_UNIT | CSR_DIRECTORY))
continue;
/* Get the address of the unit directory and try to
* match the drivers id_tables against it. */
unit = kzalloc(sizeof *unit, GFP_KERNEL);
if (unit == NULL) {
fw_error("failed to allocate memory for unit\n");
continue;
}
unit->directory = ci.p + value - 1;
unit->device.bus = &fw_bus_type;
unit->device.release = fw_unit_release;
unit->device.parent = &device->device;
snprintf(unit->device.bus_id, sizeof unit->device.bus_id,
"%s.%d", device->device.bus_id, i++);
if (device_register(&unit->device) < 0) {
kfree(unit);
continue;
}
if (device_create_file(&unit->device, &modalias_attribute) < 0) {
device_unregister(&unit->device);
kfree(unit);
}
}
}
static int shutdown_unit(struct device *device, void *data)
{
struct fw_unit *unit = fw_unit(device);
if (is_fw_unit(device)) {
device_remove_file(&unit->device, &modalias_attribute);
device_unregister(&unit->device);
}
return 0;
}
static void fw_device_shutdown(struct work_struct *work)
{
struct fw_device *device =
container_of(work, struct fw_device, work.work);
device_remove_file(&device->device, &config_rom_attribute);
cdev_del(&device->cdev);
unregister_chrdev_region(device->device.devt, 1);
device_for_each_child(&device->device, NULL, shutdown_unit);
device_unregister(&device->device);
}
/* These defines control the retry behavior for reading the config
* rom. It shouldn't be necessary to tweak these; if the device
* doesn't respond to a config rom read within 10 seconds, it's not
* going to respond at all. As for the initial delay, a lot of
* devices will be able to respond within half a second after bus
* reset. On the other hand, it's not really worth being more
* aggressive than that, since it scales pretty well; if 10 devices
* are plugged in, they're all getting read within one second. */
#define MAX_RETRIES 5
#define RETRY_DELAY (2 * HZ)
#define INITIAL_DELAY (HZ / 2)
static void fw_device_init(struct work_struct *work)
{
static atomic_t serial = ATOMIC_INIT(-1);
struct fw_device *device =
container_of(work, struct fw_device, work.work);
/* All failure paths here set node->data to NULL, so that we
* don't try to do device_for_each_child() on a kfree()'d
* device. */
if (read_bus_info_block(device) < 0) {
if (device->config_rom_retries < MAX_RETRIES) {
device->config_rom_retries++;
schedule_delayed_work(&device->work, RETRY_DELAY);
} else {
fw_notify("giving up on config rom for node id %x\n",
device->node_id);
if (device->node == device->card->root_node)
schedule_delayed_work(&device->card->work, 0);
fw_device_release(&device->device);
}
return;
}
device->device.bus = &fw_bus_type;
device->device.release = fw_device_release;
device->device.parent = device->card->device;
snprintf(device->device.bus_id, sizeof device->device.bus_id,
"fw%d", atomic_inc_return(&serial));
if (alloc_chrdev_region(&device->device.devt, 0, 1, "fw")) {
fw_error("Failed to register char device region.\n");
goto error;
}
cdev_init(&device->cdev, &fw_device_ops);
device->cdev.owner = THIS_MODULE;
kobject_set_name(&device->cdev.kobj, device->device.bus_id);
if (cdev_add(&device->cdev, device->device.devt, 1)) {
fw_error("Failed to register char device.\n");
goto error;
}
if (device_add(&device->device)) {
fw_error("Failed to add device.\n");
goto error;
}
if (device_create_file(&device->device, &config_rom_attribute) < 0) {
fw_error("Failed to create config rom file.\n");
goto error_with_device;
}
create_units(device);
/* Transition the device to running state. If it got pulled
* out from under us while we did the intialization work, we
* have to shut down the device again here. Normally, though,
* fw_node_event will be responsible for shutting it down when
* necessary. We have to use the atomic cmpxchg here to avoid
* racing with the FW_NODE_DESTROYED case in
* fw_node_event(). */
if (atomic_cmpxchg(&device->state,
FW_DEVICE_INITIALIZING,
FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN)
fw_device_shutdown(&device->work.work);
else
fw_notify("created new fw device %s (%d config rom retries)\n",
device->device.bus_id, device->config_rom_retries);
/* Reschedule the IRM work if we just finished reading the
* root node config rom. If this races with a bus reset we
* just end up running the IRM work a couple of extra times -
* pretty harmless. */
if (device->node == device->card->root_node)
schedule_delayed_work(&device->card->work, 0);
return;
error_with_device:
device_del(&device->device);
error:
cdev_del(&device->cdev);
unregister_chrdev_region(device->device.devt, 1);
put_device(&device->device);
}
static int update_unit(struct device *dev, void *data)
{
struct fw_unit *unit = fw_unit(dev);
struct fw_driver *driver = (struct fw_driver *)dev->driver;
if (is_fw_unit(dev) && driver != NULL && driver->update != NULL)
driver->update(unit);
return 0;
}
void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
{
struct fw_device *device;
switch (event) {
case FW_NODE_CREATED:
case FW_NODE_LINK_ON:
if (!node->link_on)
break;
device = kzalloc(sizeof(*device), GFP_ATOMIC);
if (device == NULL)
break;
/* Do minimal intialization of the device here, the
* rest will happen in fw_device_init(). We need the
* card and node so we can read the config rom and we
* need to do device_initialize() now so
* device_for_each_child() in FW_NODE_UPDATED is
* doesn't freak out. */
device_initialize(&device->device);
atomic_set(&device->state, FW_DEVICE_INITIALIZING);
device->card = fw_card_get(card);
device->node = fw_node_get(node);
device->node_id = node->node_id;
device->generation = card->generation;
/* Set the node data to point back to this device so
* FW_NODE_UPDATED callbacks can update the node_id
* and generation for the device. */
node->data = device;
/* Many devices are slow to respond after bus resets,
* especially if they are bus powered and go through
* power-up after getting plugged in. We schedule the
* first config rom scan half a second after bus reset. */
INIT_DELAYED_WORK(&device->work, fw_device_init);
schedule_delayed_work(&device->work, INITIAL_DELAY);
break;
case FW_NODE_UPDATED:
if (!node->link_on || node->data == NULL)
break;
device = node->data;
device->node_id = node->node_id;
device->generation = card->generation;
device_for_each_child(&device->device, NULL, update_unit);
break;
case FW_NODE_DESTROYED:
case FW_NODE_LINK_OFF:
if (!node->data)
break;
/* Destroy the device associated with the node. There
* are two cases here: either the device is fully
* initialized (FW_DEVICE_RUNNING) or we're in the
* process of reading its config rom
* (FW_DEVICE_INITIALIZING). If it is fully
* initialized we can reuse device->work to schedule a
* full fw_device_shutdown(). If not, there's work
* scheduled to read it's config rom, and we just put
* the device in shutdown state to have that code fail
* to create the device. */
device = node->data;
if (atomic_xchg(&device->state,
FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) {
INIT_DELAYED_WORK(&device->work, fw_device_shutdown);
schedule_delayed_work(&device->work, 0);
}
break;
}
}
