--- /dev/null
+/*
+ * 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/bug.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+#include <linux/idr.h>
+#include <linux/jiffies.h>
+#include <linux/kobject.h>
+#include <linux/list.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/random.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/workqueue.h>
+
+#include <linux/atomic.h>
+#include <asm/byteorder.h>
+
+#include "core.h"
+
+void fw_csr_iterator_init(struct fw_csr_iterator *ci, const 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 const u32 *search_leaf(const u32 *directory, int search_key)
+{
+ struct fw_csr_iterator ci;
+ int last_key = 0, key, value;
+
+ fw_csr_iterator_init(&ci, directory);
+ while (fw_csr_iterator_next(&ci, &key, &value)) {
+ if (last_key == search_key &&
+ key == (CSR_DESCRIPTOR | CSR_LEAF))
+ return ci.p - 1 + value;
+
+ last_key = key;
+ }
+
+ return NULL;
+}
+
+static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
+{
+ unsigned int quadlets, i;
+ char c;
+
+ if (!size || !buf)
+ return -EINVAL;
+
+ quadlets = min(block[0] >> 16, 256U);
+ if (quadlets < 2)
+ return -ENODATA;
+
+ if (block[1] != 0 || block[2] != 0)
+ /* unknown language/character set */
+ return -ENODATA;
+
+ block += 3;
+ quadlets -= 2;
+ for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
+ c = block[i / 4] >> (24 - 8 * (i % 4));
+ if (c == '\0')
+ break;
+ buf[i] = c;
+ }
+ buf[i] = '\0';
+
+ return i;
+}
+
+/**
+ * fw_csr_string() - reads a string from the configuration ROM
+ * @directory: e.g. root directory or unit directory
+ * @key: the key of the preceding directory entry
+ * @buf: where to put the string
+ * @size: size of @buf, in bytes
+ *
+ * The string is taken from a minimal ASCII text descriptor leaf after
+ * the immediate entry with @key. The string is zero-terminated.
+ * An overlong string is silently truncated such that it and the
+ * zero byte fit into @size.
+ *
+ * Returns strlen(buf) or a negative error code.
+ */
+int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
+{
+ const u32 *leaf = search_leaf(directory, key);
+ if (!leaf)
+ return -ENOENT;
+
+ return textual_leaf_to_string(leaf, buf, size);
+}
+EXPORT_SYMBOL(fw_csr_string);
+
+static void get_ids(const u32 *directory, int *id)
+{
+ struct fw_csr_iterator ci;
+ int key, value;
+
+ fw_csr_iterator_init(&ci, directory);
+ while (fw_csr_iterator_next(&ci, &key, &value)) {
+ switch (key) {
+ case CSR_VENDOR: id[0] = value; break;
+ case CSR_MODEL: id[1] = value; break;
+ case CSR_SPECIFIER_ID: id[2] = value; break;
+ case CSR_VERSION: id[3] = value; break;
+ }
+ }
+}
+
+static void get_modalias_ids(struct fw_unit *unit, int *id)
+{
+ get_ids(&fw_parent_device(unit)->config_rom[5], id);
+ get_ids(unit->directory, id);
+}
+
+static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
+{
+ int match = 0;
+
+ if (id[0] == id_table->vendor_id)
+ match |= IEEE1394_MATCH_VENDOR_ID;
+ if (id[1] == id_table->model_id)
+ match |= IEEE1394_MATCH_MODEL_ID;
+ if (id[2] == id_table->specifier_id)
+ match |= IEEE1394_MATCH_SPECIFIER_ID;
+ if (id[3] == id_table->version)
+ match |= IEEE1394_MATCH_VERSION;
+
+ return (match & id_table->match_flags) == id_table->match_flags;
+}
+
+static const struct ieee1394_device_id *unit_match(struct device *dev,
+ struct device_driver *drv)
+{
+ const struct ieee1394_device_id *id_table =
+ container_of(drv, struct fw_driver, driver)->id_table;
+ int id[] = {0, 0, 0, 0};
+
+ get_modalias_ids(fw_unit(dev), id);
+
+ for (; id_table->match_flags != 0; id_table++)
+ if (match_ids(id_table, id))
+ return id_table;
+
+ return NULL;
+}
+
+static bool is_fw_unit(struct device *dev);
+
+static int fw_unit_match(struct device *dev, struct device_driver *drv)
+{
+ /* We only allow binding to fw_units. */
+ return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
+}
+
+static int fw_unit_probe(struct device *dev)
+{
+ struct fw_driver *driver =
+ container_of(dev->driver, struct fw_driver, driver);
+
+ return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
+}
+
+static int fw_unit_remove(struct device *dev)
+{
+ struct fw_driver *driver =
+ container_of(dev->driver, struct fw_driver, driver);
+
+ return driver->remove(fw_unit(dev)), 0;
+}
+
+static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
+{
+ int id[] = {0, 0, 0, 0};
+
+ get_modalias_ids(unit, id);
+
+ return snprintf(buffer, buffer_size,
+ "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
+ id[0], id[1], id[2], id[3]);
+}
+
+static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct fw_unit *unit = fw_unit(dev);
+ char modalias[64];
+
+ get_modalias(unit, modalias, sizeof(modalias));
+
+ if (add_uevent_var(env, "MODALIAS=%s", modalias))
+ return -ENOMEM;
+
+ return 0;
+}
+
+struct bus_type fw_bus_type = {
+ .name = "firewire",
+ .match = fw_unit_match,
+ .probe = fw_unit_probe,
+ .remove = fw_unit_remove,
+};
+EXPORT_SYMBOL(fw_bus_type);
+
+int fw_device_enable_phys_dma(struct fw_device *device)
+{
+ int generation = device->generation;
+
+ /* device->node_id, accessed below, must not be older than generation */
+ smp_rmb();
+
+ return device->card->driver->enable_phys_dma(device->card,
+ device->node_id,
+ generation);
+}
+EXPORT_SYMBOL(fw_device_enable_phys_dma);
+
+struct config_rom_attribute {
+ struct device_attribute attr;
+ u32 key;
+};
+
+static ssize_t show_immediate(struct device *dev,
+ struct device_attribute *dattr, char *buf)
+{
+ struct config_rom_attribute *attr =
+ container_of(dattr, struct config_rom_attribute, attr);
+ struct fw_csr_iterator ci;
+ const u32 *dir;
+ int key, value, ret = -ENOENT;
+
+ down_read(&fw_device_rwsem);
+
+ if (is_fw_unit(dev))
+ dir = fw_unit(dev)->directory;
+ else
+ dir = fw_device(dev)->config_rom + 5;
+
+ fw_csr_iterator_init(&ci, dir);
+ while (fw_csr_iterator_next(&ci, &key, &value))
+ if (attr->key == key) {
+ ret = snprintf(buf, buf ? PAGE_SIZE : 0,
+ "0x%06x\n", value);
+ break;
+ }
+
+ up_read(&fw_device_rwsem);
+
+ return ret;
+}
+
+#define IMMEDIATE_ATTR(name, key) \
+ { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
+
+static ssize_t show_text_leaf(struct device *dev,
+ struct device_attribute *dattr, char *buf)
+{
+ struct config_rom_attribute *attr =
+ container_of(dattr, struct config_rom_attribute, attr);
+ const u32 *dir;
+ size_t bufsize;
+ char dummy_buf[2];
+ int ret;
+
+ down_read(&fw_device_rwsem);
+
+ if (is_fw_unit(dev))
+ dir = fw_unit(dev)->directory;
+ else
+ dir = fw_device(dev)->config_rom + 5;
+
+ if (buf) {
+ bufsize = PAGE_SIZE - 1;
+ } else {
+ buf = dummy_buf;
+ bufsize = 1;
+ }
+
+ ret = fw_csr_string(dir, attr->key, buf, bufsize);
+
+ if (ret >= 0) {
+ /* Strip trailing whitespace and add newline. */
+ while (ret > 0 && isspace(buf[ret - 1]))
+ ret--;
+ strcpy(buf + ret, "\n");
+ ret++;
+ }
+
+ up_read(&fw_device_rwsem);
+
+ return ret;
+}
+
+#define TEXT_LEAF_ATTR(name, key) \
+ { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
+
+static struct config_rom_attribute config_rom_attributes[] = {
+ IMMEDIATE_ATTR(vendor, CSR_VENDOR),
+ IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
+ IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
+ IMMEDIATE_ATTR(version, CSR_VERSION),
+ IMMEDIATE_ATTR(model, CSR_MODEL),
+ TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
+ TEXT_LEAF_ATTR(model_name, CSR_MODEL),
+ TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
+};
+
+static void init_fw_attribute_group(struct device *dev,
+ struct device_attribute *attrs,
+ struct fw_attribute_group *group)
+{
+ struct device_attribute *attr;
+ int i, j;
+
+ for (j = 0; attrs[j].attr.name != NULL; j++)
+ group->attrs[j] = &attrs[j].attr;
+
+ for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
+ attr = &config_rom_attributes[i].attr;
+ if (attr->show(dev, attr, NULL) < 0)
+ continue;
+ group->attrs[j++] = &attr->attr;
+ }
+
+ group->attrs[j] = NULL;
+ group->groups[0] = &group->group;
+ group->groups[1] = NULL;
+ group->group.attrs = group->attrs;
+ dev->groups = (const struct attribute_group **) group->groups;
+}
+
+static ssize_t modalias_show(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 ssize_t rom_index_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fw_device *device = fw_device(dev->parent);
+ struct fw_unit *unit = fw_unit(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n",
+ (int)(unit->directory - device->config_rom));
+}
+
+static struct device_attribute fw_unit_attributes[] = {
+ __ATTR_RO(modalias),
+ __ATTR_RO(rom_index),
+ __ATTR_NULL,
+};
+
+static ssize_t config_rom_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fw_device *device = fw_device(dev);
+ size_t length;
+
+ down_read(&fw_device_rwsem);
+ length = device->config_rom_length * 4;
+ memcpy(buf, device->config_rom, length);
+ up_read(&fw_device_rwsem);
+
+ return length;
+}
+
+static ssize_t guid_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fw_device *device = fw_device(dev);
+ int ret;
+
+ down_read(&fw_device_rwsem);
+ ret = snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
+ device->config_rom[3], device->config_rom[4]);
+ up_read(&fw_device_rwsem);
+
+ return ret;
+}
+
+static ssize_t is_local_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fw_device *device = fw_device(dev);
+
+ return sprintf(buf, "%u\n", device->is_local);
+}
+
+static int units_sprintf(char *buf, const u32 *directory)
+{
+ struct fw_csr_iterator ci;
+ int key, value;
+ int specifier_id = 0;
+ int version = 0;
+
+ fw_csr_iterator_init(&ci, 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 sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
+}
+
+static ssize_t units_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct fw_device *device = fw_device(dev);
+ struct fw_csr_iterator ci;
+ int key, value, i = 0;
+
+ down_read(&fw_device_rwsem);
+ fw_csr_iterator_init(&ci, &device->config_rom[5]);
+ while (fw_csr_iterator_next(&ci, &key, &value)) {
+ if (key != (CSR_UNIT | CSR_DIRECTORY))
+ continue;
+ i += units_sprintf(&buf[i], ci.p + value - 1);
+ if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
+ break;
+ }
+ up_read(&fw_device_rwsem);
+
+ if (i)
+ buf[i - 1] = '\n';
+
+ return i;
+}
+
+static struct device_attribute fw_device_attributes[] = {
+ __ATTR_RO(config_rom),
+ __ATTR_RO(guid),
+ __ATTR_RO(is_local),
+ __ATTR_RO(units),
+ __ATTR_NULL,
+};
+
+static int read_rom(struct fw_device *device,
+ int generation, int index, u32 *data)
+{
+ u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
+ int i, rcode;
+
+ /* device->node_id, accessed below, must not be older than generation */
+ smp_rmb();
+
+ for (i = 10; i < 100; i += 10) {
+ rcode = fw_run_transaction(device->card,
+ TCODE_READ_QUADLET_REQUEST, device->node_id,
+ generation, device->max_speed, offset, data, 4);
+ if (rcode != RCODE_BUSY)
+ break;
+ msleep(i);
+ }
+ be32_to_cpus(data);
+
+ return rcode;
+}
+
+#define MAX_CONFIG_ROM_SIZE 256
+
+/*
+ * Read the bus info block, perform a speed probe, and read all of the rest of
+ * the config ROM. We do all this with a cached bus generation. If the bus
+ * generation changes under us, read_config_rom will fail and get retried.
+ * It's better to start all over in this case because the node from which we
+ * are reading the ROM may have changed the ROM during the reset.
+ * Returns either a result code or a negative error code.
+ */
+static int read_config_rom(struct fw_device *device, int generation)
+{
+ struct fw_card *card = device->card;
+ const u32 *old_rom, *new_rom;
+ u32 *rom, *stack;
+ u32 sp, key;
+ int i, end, length, ret;
+
+ rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
+ sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
+ if (rom == NULL)
+ return -ENOMEM;
+
+ stack = &rom[MAX_CONFIG_ROM_SIZE];
+ memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
+
+ device->max_speed = SCODE_100;
+
+ /* First read the bus info block. */
+ for (i = 0; i < 5; i++) {
+ ret = read_rom(device, generation, i, &rom[i]);
+ if (ret != RCODE_COMPLETE)
+ goto out;
+ /*
+ * As per IEEE1212 7.2, during initialization, 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) {
+ ret = RCODE_BUSY;
+ goto out;
+ }
+ }
+
+ device->max_speed = device->node->max_speed;
+
+ /*
+ * Determine the speed of
+ * - devices with link speed less than PHY speed,
+ * - devices with 1394b PHY (unless only connected to 1394a PHYs),
+ * - all devices if there are 1394b repeaters.
+ * Note, we cannot use the bus info block's link_spd as starting point
+ * because some buggy firmwares set it lower than necessary and because
+ * 1394-1995 nodes do not have the field.
+ */
+ if ((rom[2] & 0x7) < device->max_speed ||
+ device->max_speed == SCODE_BETA ||
+ card->beta_repeaters_present) {
+ u32 dummy;
+
+ /* for S1600 and S3200 */
+ if (device->max_speed == SCODE_BETA)
+ device->max_speed = card->link_speed;
+
+ while (device->max_speed > SCODE_100) {
+ if (read_rom(device, generation, 0, &dummy) ==
+ RCODE_COMPLETE)
+ break;
+ device->max_speed--;
+ }
+ }
+
+ /*
+ * 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 (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
+ ret = -ENXIO;
+ goto out;
+ }
+
+ /* Read header quadlet for the block to get the length. */
+ ret = read_rom(device, generation, i, &rom[i]);
+ if (ret != RCODE_COMPLETE)
+ goto out;
+ end = i + (rom[i] >> 16) + 1;
+ if (end > MAX_CONFIG_ROM_SIZE) {
+ /*
+ * This block extends outside the config ROM which is
+ * a firmware bug. Ignore this whole block, i.e.
+ * simply set a fake block length of 0.
+ */
+ fw_err(card, "skipped invalid ROM block %x at %llx\n",
+ rom[i],
+ i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
+ rom[i] = 0;
+ end = i;
+ }
+ i++;
+
+ /*
+ * 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.
+ */
+ for (; i < end; i++) {
+ ret = read_rom(device, generation, i, &rom[i]);
+ if (ret != RCODE_COMPLETE)
+ goto out;
+
+ if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
+ continue;
+ /*
+ * Offset points outside the ROM. May be a firmware
+ * bug or an Extended ROM entry (IEEE 1212-2001 clause
+ * 7.7.18). Simply overwrite this pointer here by a
+ * fake immediate entry so that later iterators over
+ * the ROM don't have to check offsets all the time.
+ */
+ if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
+ fw_err(card,
+ "skipped unsupported ROM entry %x at %llx\n",
+ rom[i],
+ i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
+ rom[i] = 0;
+ continue;
+ }
+ stack[sp++] = i + rom[i];
+ }
+ if (length < i)
+ length = i;
+ }
+
+ old_rom = device->config_rom;
+ new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
+ if (new_rom == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ down_write(&fw_device_rwsem);
+ device->config_rom = new_rom;
+ device->config_rom_length = length;
+ up_write(&fw_device_rwsem);
+
+ kfree(old_rom);
+ ret = RCODE_COMPLETE;
+ device->max_rec = rom[2] >> 12 & 0xf;
+ device->cmc = rom[2] >> 30 & 1;
+ device->irmc = rom[2] >> 31 & 1;
+ out:
+ kfree(rom);
+
+ return ret;
+}
+
+static void fw_unit_release(struct device *dev)
+{
+ struct fw_unit *unit = fw_unit(dev);
+
+ fw_device_put(fw_parent_device(unit));
+ kfree(unit);
+}
+
+static struct device_type fw_unit_type = {
+ .uevent = fw_unit_uevent,
+ .release = fw_unit_release,
+};
+
+static bool is_fw_unit(struct device *dev)
+{
+ return dev->type == &fw_unit_type;
+}
+
+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)
+ continue;
+
+ unit->directory = ci.p + value - 1;
+ unit->device.bus = &fw_bus_type;
+ unit->device.type = &fw_unit_type;
+ unit->device.parent = &device->device;
+ dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
+
+ BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
+ ARRAY_SIZE(fw_unit_attributes) +
+ ARRAY_SIZE(config_rom_attributes));
+ init_fw_attribute_group(&unit->device,
+ fw_unit_attributes,
+ &unit->attribute_group);
+
+ if (device_register(&unit->device) < 0)
+ goto skip_unit;
+
+ fw_device_get(device);
+ continue;
+
+ skip_unit:
+ kfree(unit);
+ }
+}
+
+static int shutdown_unit(struct device *device, void *data)
+{
+ device_unregister(device);
+
+ return 0;
+}
+
+/*
+ * fw_device_rwsem acts as dual purpose mutex:
+ * - serializes accesses to fw_device_idr,
+ * - serializes accesses to fw_device.config_rom/.config_rom_length and
+ * fw_unit.directory, unless those accesses happen at safe occasions
+ */
+DECLARE_RWSEM(fw_device_rwsem);
+
+DEFINE_IDR(fw_device_idr);
+int fw_cdev_major;
+
+struct fw_device *fw_device_get_by_devt(dev_t devt)
+{
+ struct fw_device *device;
+
+ down_read(&fw_device_rwsem);
+ device = idr_find(&fw_device_idr, MINOR(devt));
+ if (device)
+ fw_device_get(device);
+ up_read(&fw_device_rwsem);
+
+ return device;
+}
+
+struct workqueue_struct *fw_workqueue;
+EXPORT_SYMBOL(fw_workqueue);
+
+static void fw_schedule_device_work(struct fw_device *device,
+ unsigned long delay)
+{
+ queue_delayed_work(fw_workqueue, &device->work, delay);
+}
+
+/*
+ * 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 10
+#define RETRY_DELAY (3 * HZ)
+#define INITIAL_DELAY (HZ / 2)
+#define SHUTDOWN_DELAY (2 * HZ)
+
+static void fw_device_shutdown(struct work_struct *work)
+{
+ struct fw_device *device =
+ container_of(work, struct fw_device, work.work);
+ int minor = MINOR(device->device.devt);
+
+ if (time_before64(get_jiffies_64(),
+ device->card->reset_jiffies + SHUTDOWN_DELAY)
+ && !list_empty(&device->card->link)) {
+ fw_schedule_device_work(device, SHUTDOWN_DELAY);
+ return;
+ }
+
+ if (atomic_cmpxchg(&device->state,
+ FW_DEVICE_GONE,
+ FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
+ return;
+
+ fw_device_cdev_remove(device);
+ device_for_each_child(&device->device, NULL, shutdown_unit);
+ device_unregister(&device->device);
+
+ down_write(&fw_device_rwsem);
+ idr_remove(&fw_device_idr, minor);
+ up_write(&fw_device_rwsem);
+
+ fw_device_put(device);
+}
+
+static void fw_device_release(struct device *dev)
+{
+ struct fw_device *device = fw_device(dev);
+ struct fw_card *card = device->card;
+ unsigned long flags;
+
+ /*
+ * Take the card lock so we don't set this to NULL while a
+ * FW_NODE_UPDATED callback is being handled or while the
+ * bus manager work looks at this node.
+ */
+ spin_lock_irqsave(&card->lock, flags);
+ device->node->data = NULL;
+ spin_unlock_irqrestore(&card->lock, flags);
+
+ fw_node_put(device->node);
+ kfree(device->config_rom);
+ kfree(device);
+ fw_card_put(card);
+}
+
+static struct device_type fw_device_type = {
+ .release = fw_device_release,
+};
+
+static bool is_fw_device(struct device *dev)
+{
+ return dev->type == &fw_device_type;
+}
+
+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) {
+ device_lock(dev);
+ driver->update(unit);
+ device_unlock(dev);
+ }
+
+ return 0;
+}
+
+static void fw_device_update(struct work_struct *work)
+{
+ struct fw_device *device =
+ container_of(work, struct fw_device, work.work);
+
+ fw_device_cdev_update(device);
+ device_for_each_child(&device->device, NULL, update_unit);
+}
+
+/*
+ * If a device was pending for deletion because its node went away but its
+ * bus info block and root directory header matches that of a newly discovered
+ * device, revive the existing fw_device.
+ * The newly allocated fw_device becomes obsolete instead.
+ */
+static int lookup_existing_device(struct device *dev, void *data)
+{
+ struct fw_device *old = fw_device(dev);
+ struct fw_device *new = data;
+ struct fw_card *card = new->card;
+ int match = 0;
+
+ if (!is_fw_device(dev))
+ return 0;
+
+ down_read(&fw_device_rwsem); /* serialize config_rom access */
+ spin_lock_irq(&card->lock); /* serialize node access */
+
+ if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
+ atomic_cmpxchg(&old->state,
+ FW_DEVICE_GONE,
+ FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
+ struct fw_node *current_node = new->node;
+ struct fw_node *obsolete_node = old->node;
+
+ new->node = obsolete_node;
+ new->node->data = new;
+ old->node = current_node;
+ old->node->data = old;
+
+ old->max_speed = new->max_speed;
+ old->node_id = current_node->node_id;
+ smp_wmb(); /* update node_id before generation */
+ old->generation = card->generation;
+ old->config_rom_retries = 0;
+ fw_notice(card, "rediscovered device %s\n", dev_name(dev));
+
+ old->workfn = fw_device_update;
+ fw_schedule_device_work(old, 0);
+
+ if (current_node == card->root_node)
+ fw_schedule_bm_work(card, 0);
+
+ match = 1;
+ }
+
+ spin_unlock_irq(&card->lock);
+ up_read(&fw_device_rwsem);
+
+ return match;
+}
+
+enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
+
+static void set_broadcast_channel(struct fw_device *device, int generation)
+{
+ struct fw_card *card = device->card;
+ __be32 data;
+ int rcode;
+
+ if (!card->broadcast_channel_allocated)
+ return;
+
+ /*
+ * The Broadcast_Channel Valid bit is required by nodes which want to
+ * transmit on this channel. Such transmissions are practically
+ * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
+ * to be IRM capable and have a max_rec of 8 or more. We use this fact
+ * to narrow down to which nodes we send Broadcast_Channel updates.
+ */
+ if (!device->irmc || device->max_rec < 8)
+ return;
+
+ /*
+ * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
+ * Perform a read test first.
+ */
+ if (device->bc_implemented == BC_UNKNOWN) {
+ rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
+ device->node_id, generation, device->max_speed,
+ CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
+ &data, 4);
+ switch (rcode) {
+ case RCODE_COMPLETE:
+ if (data & cpu_to_be32(1 << 31)) {
+ device->bc_implemented = BC_IMPLEMENTED;
+ break;
+ }
+ /* else fall through to case address error */
+ case RCODE_ADDRESS_ERROR:
+ device->bc_implemented = BC_UNIMPLEMENTED;
+ }
+ }
+
+ if (device->bc_implemented == BC_IMPLEMENTED) {
+ data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
+ BROADCAST_CHANNEL_VALID);
+ fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
+ device->node_id, generation, device->max_speed,
+ CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
+ &data, 4);
+ }
+}
+
+int fw_device_set_broadcast_channel(struct device *dev, void *gen)
+{
+ if (is_fw_device(dev))
+ set_broadcast_channel(fw_device(dev), (long)gen);
+
+ return 0;
+}
+
+static void fw_device_init(struct work_struct *work)
+{
+ struct fw_device *device =
+ container_of(work, struct fw_device, work.work);
+ struct fw_card *card = device->card;
+ struct device *revived_dev;
+ int minor, ret;
+
+ /*
+ * 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.
+ */
+
+ ret = read_config_rom(device, device->generation);
+ if (ret != RCODE_COMPLETE) {
+ if (device->config_rom_retries < MAX_RETRIES &&
+ atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
+ device->config_rom_retries++;
+ fw_schedule_device_work(device, RETRY_DELAY);
+ } else {
+ if (device->node->link_on)
+ fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
+ device->node_id,
+ fw_rcode_string(ret));
+ if (device->node == card->root_node)
+ fw_schedule_bm_work(card, 0);
+ fw_device_release(&device->device);
+ }
+ return;
+ }
+
+ revived_dev = device_find_child(card->device,
+ device, lookup_existing_device);
+ if (revived_dev) {
+ put_device(revived_dev);
+ fw_device_release(&device->device);
+
+ return;
+ }
+
+ device_initialize(&device->device);
+
+ fw_device_get(device);
+ down_write(&fw_device_rwsem);
+ minor = idr_alloc(&fw_device_idr, device, 0, 1 << MINORBITS,
+ GFP_KERNEL);
+ up_write(&fw_device_rwsem);
+
+ if (minor < 0)
+ goto error;
+
+ device->device.bus = &fw_bus_type;
+ device->device.type = &fw_device_type;
+ device->device.parent = card->device;
+ device->device.devt = MKDEV(fw_cdev_major, minor);
+ dev_set_name(&device->device, "fw%d", minor);
+
+ BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
+ ARRAY_SIZE(fw_device_attributes) +
+ ARRAY_SIZE(config_rom_attributes));
+ init_fw_attribute_group(&device->device,
+ fw_device_attributes,
+ &device->attribute_group);
+
+ if (device_add(&device->device)) {
+ fw_err(card, "failed to add device\n");
+ goto error_with_cdev;
+ }
+
+ 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_GONE) {
+ device->workfn = fw_device_shutdown;
+ fw_schedule_device_work(device, SHUTDOWN_DELAY);
+ } else {
+ fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
+ dev_name(&device->device),
+ device->config_rom[3], device->config_rom[4],
+ 1 << device->max_speed);
+ device->config_rom_retries = 0;
+
+ set_broadcast_channel(device, device->generation);
+
+ add_device_randomness(&device->config_rom[3], 8);
+ }
+
+ /*
+ * 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 == card->root_node)
+ fw_schedule_bm_work(card, 0);
+
+ return;
+
+ error_with_cdev:
+ down_write(&fw_device_rwsem);
+ idr_remove(&fw_device_idr, minor);
+ up_write(&fw_device_rwsem);
+ error:
+ fw_device_put(device); /* fw_device_idr's reference */
+
+ put_device(&device->device); /* our reference */
+}
+
+/* Reread and compare bus info block and header of root directory */
+static int reread_config_rom(struct fw_device *device, int generation,
+ bool *changed)
+{
+ u32 q;
+ int i, rcode;
+
+ for (i = 0; i < 6; i++) {
+ rcode = read_rom(device, generation, i, &q);
+ if (rcode != RCODE_COMPLETE)
+ return rcode;
+
+ if (i == 0 && q == 0)
+ /* inaccessible (see read_config_rom); retry later */
+ return RCODE_BUSY;
+
+ if (q != device->config_rom[i]) {
+ *changed = true;
+ return RCODE_COMPLETE;
+ }
+ }
+
+ *changed = false;
+ return RCODE_COMPLETE;
+}
+
+static void fw_device_refresh(struct work_struct *work)
+{
+ struct fw_device *device =
+ container_of(work, struct fw_device, work.work);
+ struct fw_card *card = device->card;
+ int ret, node_id = device->node_id;
+ bool changed;
+
+ ret = reread_config_rom(device, device->generation, &changed);
+ if (ret != RCODE_COMPLETE)
+ goto failed_config_rom;
+
+ if (!changed) {
+ if (atomic_cmpxchg(&device->state,
+ FW_DEVICE_INITIALIZING,
+ FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
+ goto gone;
+
+ fw_device_update(work);
+ device->config_rom_retries = 0;
+ goto out;
+ }
+
+ /*
+ * Something changed. We keep things simple and don't investigate
+ * further. We just destroy all previous units and create new ones.
+ */
+ device_for_each_child(&device->device, NULL, shutdown_unit);
+
+ ret = read_config_rom(device, device->generation);
+ if (ret != RCODE_COMPLETE)
+ goto failed_config_rom;
+
+ fw_device_cdev_update(device);
+ create_units(device);
+
+ /* Userspace may want to re-read attributes. */
+ kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
+
+ if (atomic_cmpxchg(&device->state,
+ FW_DEVICE_INITIALIZING,
+ FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
+ goto gone;
+
+ fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
+ device->config_rom_retries = 0;
+ goto out;
+
+ failed_config_rom:
+ if (device->config_rom_retries < MAX_RETRIES &&
+ atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
+ device->config_rom_retries++;
+ fw_schedule_device_work(device, RETRY_DELAY);
+ return;
+ }
+
+ fw_notice(card, "giving up on refresh of device %s: %s\n",
+ dev_name(&device->device), fw_rcode_string(ret));
+ gone:
+ atomic_set(&device->state, FW_DEVICE_GONE);
+ device->workfn = fw_device_shutdown;
+ fw_schedule_device_work(device, SHUTDOWN_DELAY);
+ out:
+ if (node_id == card->root_node->node_id)
+ fw_schedule_bm_work(card, 0);
+}
+
+static void fw_device_workfn(struct work_struct *work)
+{
+ struct fw_device *device = container_of(to_delayed_work(work),
+ struct fw_device, work);
+ device->workfn(work);
+}
+
+void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
+{
+ struct fw_device *device;
+
+ switch (event) {
+ case FW_NODE_CREATED:
+ /*
+ * Attempt to scan the node, regardless whether its self ID has
+ * the L (link active) flag set or not. Some broken devices
+ * send L=0 but have an up-and-running link; others send L=1
+ * without actually having a link.
+ */
+ create:
+ 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().
+ *
+ * Attention: A lot of things, even fw_device_get(),
+ * cannot be done before fw_device_init() finished!
+ * You can basically just check device->state and
+ * schedule work until then, but only while holding
+ * card->lock.
+ */
+ 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;
+ device->is_local = node == card->local_node;
+ mutex_init(&device->client_list_mutex);
+ INIT_LIST_HEAD(&device->client_list);
+
+ /*
+ * 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.
+ */
+ device->workfn = fw_device_init;
+ INIT_DELAYED_WORK(&device->work, fw_device_workfn);
+ fw_schedule_device_work(device, INITIAL_DELAY);
+ break;
+
+ case FW_NODE_INITIATED_RESET:
+ case FW_NODE_LINK_ON:
+ device = node->data;
+ if (device == NULL)
+ goto create;
+
+ device->node_id = node->node_id;
+ smp_wmb(); /* update node_id before generation */
+ device->generation = card->generation;
+ if (atomic_cmpxchg(&device->state,
+ FW_DEVICE_RUNNING,
+ FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
+ device->workfn = fw_device_refresh;
+ fw_schedule_device_work(device,
+ device->is_local ? 0 : INITIAL_DELAY);
+ }
+ break;
+
+ case FW_NODE_UPDATED:
+ device = node->data;
+ if (device == NULL)
+ break;
+
+ device->node_id = node->node_id;
+ smp_wmb(); /* update node_id before generation */
+ device->generation = card->generation;
+ if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
+ device->workfn = fw_device_update;
+ fw_schedule_device_work(device, 0);
+ }
+ 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_GONE) == FW_DEVICE_RUNNING) {
+ device->workfn = fw_device_shutdown;
+ fw_schedule_device_work(device,
+ list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
+ }
+ break;
+ }
+}
Code Review / kvmfornfv.git / blobdiff