firewire: Add device probing and sysfs integration.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
new file mode 100644
index 0000000..ec1cb7f
--- /dev/null
+++ b/drivers/firewire/fw-device.c
@@ -0,0 +1,613 @@
+/* -*- 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, 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 = "fw",
+ .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 | LOCAL_BUS,
+ 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 int serial;
+ 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 %d\n",
+ device->node_id);
+ 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", 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 (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;
+
+ /* Ignore events for the local node (i.e. the node that
+ * corresponds to the ieee1394 controller in this linux box). */
+ if (node == card->local_node)
+ return;
+
+ 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);
+ 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 (xchg(&device->state,
+ FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) {
+ INIT_DELAYED_WORK(&device->work, fw_device_shutdown);
+ schedule_delayed_work(&device->work, 0);
+ }
+ break;
+ }
+}