| /* |
| * 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/rwsem.h> |
| #include <linux/slab.h> |
| #include <linux/spinlock.h> |
| #include <linux/string.h> |
| #include <linux/workqueue.h> |
| |
| #include <asm/atomic.h> |
| #include <asm/byteorder.h> |
| #include <asm/system.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. |
| * 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 bool is_fw_unit(struct device *dev); |
| |
| static int fw_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}; |
| |
| /* We only allow binding to fw_units. */ |
| if (!is_fw_unit(dev)) |
| return 0; |
| |
| get_modalias_ids(fw_unit(dev), id); |
| |
| for (; id_table->match_flags != 0; id_table++) |
| if (match_ids(id_table, id)) |
| return 1; |
| |
| return 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, |
| }; |
| 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 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(units), |
| __ATTR_NULL, |
| }; |
| |
| static int read_rom(struct fw_device *device, |
| int generation, int index, u32 *data) |
| { |
| int rcode; |
| |
| /* device->node_id, accessed below, must not be older than generation */ |
| smp_rmb(); |
| |
| rcode = fw_run_transaction(device->card, TCODE_READ_QUADLET_REQUEST, |
| device->node_id, generation, device->max_speed, |
| (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4, |
| data, 4); |
| 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. |
| */ |
| static int read_config_rom(struct fw_device *device, int generation) |
| { |
| const u32 *old_rom, *new_rom; |
| u32 *rom, *stack; |
| u32 sp, key; |
| int i, end, length, ret = -1; |
| |
| 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++) { |
| if (read_rom(device, generation, i, &rom[i]) != RCODE_COMPLETE) |
| goto out; |
| /* |
| * 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) |
| 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 || |
| device->card->beta_repeaters_present) { |
| u32 dummy; |
| |
| /* for S1600 and S3200 */ |
| if (device->max_speed == SCODE_BETA) |
| device->max_speed = device->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)) |
| goto out; |
| |
| /* Read header quadlet for the block to get the length. */ |
| if (read_rom(device, generation, i, &rom[i]) != 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_error("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++) { |
| if (read_rom(device, generation, i, &rom[i]) != |
| 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_error("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) |
| 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 = 0; |
| 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); |
| |
| 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) { |
| fw_error("failed to allocate memory for unit\n"); |
| 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; |
| |
| 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_wq; |
| |
| static void fw_schedule_device_work(struct fw_device *device, |
| unsigned long delay) |
| { |
| queue_delayed_work(fw_wq, &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_notify("rediscovered device %s\n", dev_name(dev)); |
| |
| PREPARE_DELAYED_WORK(&old->work, 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 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. |
| */ |
| |
| if (read_config_rom(device, device->generation) < 0) { |
| 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_notify("giving up on config rom for node id %x\n", |
| device->node_id); |
| if (device->node == device->card->root_node) |
| fw_schedule_bm_work(device->card, 0); |
| fw_device_release(&device->device); |
| } |
| return; |
| } |
| |
| revived_dev = device_find_child(device->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); |
| ret = idr_pre_get(&fw_device_idr, GFP_KERNEL) ? |
| idr_get_new(&fw_device_idr, device, &minor) : |
| -ENOMEM; |
| up_write(&fw_device_rwsem); |
| |
| if (ret < 0) |
| goto error; |
| |
| device->device.bus = &fw_bus_type; |
| device->device.type = &fw_device_type; |
| device->device.parent = device->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_error("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) { |
| PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown); |
| fw_schedule_device_work(device, SHUTDOWN_DELAY); |
| } else { |
| if (device->config_rom_retries) |
| fw_notify("created device %s: GUID %08x%08x, S%d00, " |
| "%d config ROM retries\n", |
| dev_name(&device->device), |
| device->config_rom[3], device->config_rom[4], |
| 1 << device->max_speed, |
| device->config_rom_retries); |
| else |
| fw_notify("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); |
| } |
| |
| /* |
| * 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) |
| fw_schedule_bm_work(device->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 */ |
| } |
| |
| enum { |
| REREAD_BIB_ERROR, |
| REREAD_BIB_GONE, |
| REREAD_BIB_UNCHANGED, |
| REREAD_BIB_CHANGED, |
| }; |
| |
| /* Reread and compare bus info block and header of root directory */ |
| static int reread_config_rom(struct fw_device *device, int generation) |
| { |
| u32 q; |
| int i; |
| |
| for (i = 0; i < 6; i++) { |
| if (read_rom(device, generation, i, &q) != RCODE_COMPLETE) |
| return REREAD_BIB_ERROR; |
| |
| if (i == 0 && q == 0) |
| return REREAD_BIB_GONE; |
| |
| if (q != device->config_rom[i]) |
| return REREAD_BIB_CHANGED; |
| } |
| |
| return REREAD_BIB_UNCHANGED; |
| } |
| |
| 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 node_id = device->node_id; |
| |
| switch (reread_config_rom(device, device->generation)) { |
| case REREAD_BIB_ERROR: |
| if (device->config_rom_retries < MAX_RETRIES / 2 && |
| atomic_read(&device->state) == FW_DEVICE_INITIALIZING) { |
| device->config_rom_retries++; |
| fw_schedule_device_work(device, RETRY_DELAY / 2); |
| |
| return; |
| } |
| goto give_up; |
| |
| case REREAD_BIB_GONE: |
| goto gone; |
| |
| case REREAD_BIB_UNCHANGED: |
| 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; |
| |
| case REREAD_BIB_CHANGED: |
| break; |
| } |
| |
| /* |
| * 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); |
| |
| if (read_config_rom(device, device->generation) < 0) { |
| 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; |
| } |
| goto give_up; |
| } |
| |
| 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_notify("refreshed device %s\n", dev_name(&device->device)); |
| device->config_rom_retries = 0; |
| goto out; |
| |
| give_up: |
| fw_notify("giving up on refresh of device %s\n", dev_name(&device->device)); |
| gone: |
| atomic_set(&device->state, FW_DEVICE_GONE); |
| PREPARE_DELAYED_WORK(&device->work, 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); |
| } |
| |
| 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. |
| */ |
| INIT_DELAYED_WORK(&device->work, fw_device_init); |
| 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) { |
| PREPARE_DELAYED_WORK(&device->work, 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) { |
| PREPARE_DELAYED_WORK(&device->work, 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) { |
| PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown); |
| fw_schedule_device_work(device, |
| list_empty(&card->link) ? 0 : SHUTDOWN_DELAY); |
| } |
| break; |
| } |
| } |