[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/thunderbolt/switch.c b/src/kernel/linux/v4.14/drivers/thunderbolt/switch.c
new file mode 100644
index 0000000..9cfc65c
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/thunderbolt/switch.c
@@ -0,0 +1,1571 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Thunderbolt Cactus Ridge driver - switch/port utility functions
+ *
+ * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/idr.h>
+#include <linux/nvmem-provider.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include "tb.h"
+
+/* Switch authorization from userspace is serialized by this lock */
+static DEFINE_MUTEX(switch_lock);
+
+/* Switch NVM support */
+
+#define NVM_DEVID 0x05
+#define NVM_VERSION 0x08
+#define NVM_CSS 0x10
+#define NVM_FLASH_SIZE 0x45
+
+#define NVM_MIN_SIZE SZ_32K
+#define NVM_MAX_SIZE SZ_512K
+
+static DEFINE_IDA(nvm_ida);
+
+struct nvm_auth_status {
+ struct list_head list;
+ uuid_t uuid;
+ u32 status;
+};
+
+/*
+ * Hold NVM authentication failure status per switch This information
+ * needs to stay around even when the switch gets power cycled so we
+ * keep it separately.
+ */
+static LIST_HEAD(nvm_auth_status_cache);
+static DEFINE_MUTEX(nvm_auth_status_lock);
+
+static struct nvm_auth_status *__nvm_get_auth_status(const struct tb_switch *sw)
+{
+ struct nvm_auth_status *st;
+
+ list_for_each_entry(st, &nvm_auth_status_cache, list) {
+ if (uuid_equal(&st->uuid, sw->uuid))
+ return st;
+ }
+
+ return NULL;
+}
+
+static void nvm_get_auth_status(const struct tb_switch *sw, u32 *status)
+{
+ struct nvm_auth_status *st;
+
+ mutex_lock(&nvm_auth_status_lock);
+ st = __nvm_get_auth_status(sw);
+ mutex_unlock(&nvm_auth_status_lock);
+
+ *status = st ? st->status : 0;
+}
+
+static void nvm_set_auth_status(const struct tb_switch *sw, u32 status)
+{
+ struct nvm_auth_status *st;
+
+ if (WARN_ON(!sw->uuid))
+ return;
+
+ mutex_lock(&nvm_auth_status_lock);
+ st = __nvm_get_auth_status(sw);
+
+ if (!st) {
+ st = kzalloc(sizeof(*st), GFP_KERNEL);
+ if (!st)
+ goto unlock;
+
+ memcpy(&st->uuid, sw->uuid, sizeof(st->uuid));
+ INIT_LIST_HEAD(&st->list);
+ list_add_tail(&st->list, &nvm_auth_status_cache);
+ }
+
+ st->status = status;
+unlock:
+ mutex_unlock(&nvm_auth_status_lock);
+}
+
+static void nvm_clear_auth_status(const struct tb_switch *sw)
+{
+ struct nvm_auth_status *st;
+
+ mutex_lock(&nvm_auth_status_lock);
+ st = __nvm_get_auth_status(sw);
+ if (st) {
+ list_del(&st->list);
+ kfree(st);
+ }
+ mutex_unlock(&nvm_auth_status_lock);
+}
+
+static int nvm_validate_and_write(struct tb_switch *sw)
+{
+ unsigned int image_size, hdr_size;
+ const u8 *buf = sw->nvm->buf;
+ u16 ds_size;
+ int ret;
+
+ if (!buf)
+ return -EINVAL;
+
+ image_size = sw->nvm->buf_data_size;
+ if (image_size < NVM_MIN_SIZE || image_size > NVM_MAX_SIZE)
+ return -EINVAL;
+
+ /*
+ * FARB pointer must point inside the image and must at least
+ * contain parts of the digital section we will be reading here.
+ */
+ hdr_size = (*(u32 *)buf) & 0xffffff;
+ if (hdr_size + NVM_DEVID + 2 >= image_size)
+ return -EINVAL;
+
+ /* Digital section start should be aligned to 4k page */
+ if (!IS_ALIGNED(hdr_size, SZ_4K))
+ return -EINVAL;
+
+ /*
+ * Read digital section size and check that it also fits inside
+ * the image.
+ */
+ ds_size = *(u16 *)(buf + hdr_size);
+ if (ds_size >= image_size)
+ return -EINVAL;
+
+ if (!sw->safe_mode) {
+ u16 device_id;
+
+ /*
+ * Make sure the device ID in the image matches the one
+ * we read from the switch config space.
+ */
+ device_id = *(u16 *)(buf + hdr_size + NVM_DEVID);
+ if (device_id != sw->config.device_id)
+ return -EINVAL;
+
+ if (sw->generation < 3) {
+ /* Write CSS headers first */
+ ret = dma_port_flash_write(sw->dma_port,
+ DMA_PORT_CSS_ADDRESS, buf + NVM_CSS,
+ DMA_PORT_CSS_MAX_SIZE);
+ if (ret)
+ return ret;
+ }
+
+ /* Skip headers in the image */
+ buf += hdr_size;
+ image_size -= hdr_size;
+ }
+
+ return dma_port_flash_write(sw->dma_port, 0, buf, image_size);
+}
+
+static int nvm_authenticate_host(struct tb_switch *sw)
+{
+ int ret;
+
+ /*
+ * Root switch NVM upgrade requires that we disconnect the
+ * existing PCIe paths first (in case it is not in safe mode
+ * already).
+ */
+ if (!sw->safe_mode) {
+ ret = tb_domain_disconnect_pcie_paths(sw->tb);
+ if (ret)
+ return ret;
+ /*
+ * The host controller goes away pretty soon after this if
+ * everything goes well so getting timeout is expected.
+ */
+ ret = dma_port_flash_update_auth(sw->dma_port);
+ return ret == -ETIMEDOUT ? 0 : ret;
+ }
+
+ /*
+ * From safe mode we can get out by just power cycling the
+ * switch.
+ */
+ dma_port_power_cycle(sw->dma_port);
+ return 0;
+}
+
+static int nvm_authenticate_device(struct tb_switch *sw)
+{
+ int ret, retries = 10;
+
+ ret = dma_port_flash_update_auth(sw->dma_port);
+ if (ret && ret != -ETIMEDOUT)
+ return ret;
+
+ /*
+ * Poll here for the authentication status. It takes some time
+ * for the device to respond (we get timeout for a while). Once
+ * we get response the device needs to be power cycled in order
+ * to the new NVM to be taken into use.
+ */
+ do {
+ u32 status;
+
+ ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
+ if (ret < 0 && ret != -ETIMEDOUT)
+ return ret;
+ if (ret > 0) {
+ if (status) {
+ tb_sw_warn(sw, "failed to authenticate NVM\n");
+ nvm_set_auth_status(sw, status);
+ }
+
+ tb_sw_info(sw, "power cycling the switch now\n");
+ dma_port_power_cycle(sw->dma_port);
+ return 0;
+ }
+
+ msleep(500);
+ } while (--retries);
+
+ return -ETIMEDOUT;
+}
+
+static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct tb_switch *sw = priv;
+
+ return dma_port_flash_read(sw->dma_port, offset, val, bytes);
+}
+
+static int tb_switch_nvm_no_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ return -EPERM;
+}
+
+static int tb_switch_nvm_write(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct tb_switch *sw = priv;
+ int ret = 0;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ /*
+ * Since writing the NVM image might require some special steps,
+ * for example when CSS headers are written, we cache the image
+ * locally here and handle the special cases when the user asks
+ * us to authenticate the image.
+ */
+ if (!sw->nvm->buf) {
+ sw->nvm->buf = vmalloc(NVM_MAX_SIZE);
+ if (!sw->nvm->buf) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+ }
+
+ sw->nvm->buf_data_size = offset + bytes;
+ memcpy(sw->nvm->buf + offset, val, bytes);
+
+unlock:
+ mutex_unlock(&switch_lock);
+
+ return ret;
+}
+
+static struct nvmem_device *register_nvmem(struct tb_switch *sw, int id,
+ size_t size, bool active)
+{
+ struct nvmem_config config;
+
+ memset(&config, 0, sizeof(config));
+
+ if (active) {
+ config.name = "nvm_active";
+ config.reg_read = tb_switch_nvm_read;
+ config.read_only = true;
+ } else {
+ config.name = "nvm_non_active";
+ config.reg_read = tb_switch_nvm_no_read;
+ config.reg_write = tb_switch_nvm_write;
+ config.root_only = true;
+ }
+
+ config.id = id;
+ config.stride = 4;
+ config.word_size = 4;
+ config.size = size;
+ config.dev = &sw->dev;
+ config.owner = THIS_MODULE;
+ config.priv = sw;
+
+ return nvmem_register(&config);
+}
+
+static int tb_switch_nvm_add(struct tb_switch *sw)
+{
+ struct nvmem_device *nvm_dev;
+ struct tb_switch_nvm *nvm;
+ u32 val;
+ int ret;
+
+ if (!sw->dma_port)
+ return 0;
+
+ nvm = kzalloc(sizeof(*nvm), GFP_KERNEL);
+ if (!nvm)
+ return -ENOMEM;
+
+ nvm->id = ida_simple_get(&nvm_ida, 0, 0, GFP_KERNEL);
+
+ /*
+ * If the switch is in safe-mode the only accessible portion of
+ * the NVM is the non-active one where userspace is expected to
+ * write new functional NVM.
+ */
+ if (!sw->safe_mode) {
+ u32 nvm_size, hdr_size;
+
+ ret = dma_port_flash_read(sw->dma_port, NVM_FLASH_SIZE, &val,
+ sizeof(val));
+ if (ret)
+ goto err_ida;
+
+ hdr_size = sw->generation < 3 ? SZ_8K : SZ_16K;
+ nvm_size = (SZ_1M << (val & 7)) / 8;
+ nvm_size = (nvm_size - hdr_size) / 2;
+
+ ret = dma_port_flash_read(sw->dma_port, NVM_VERSION, &val,
+ sizeof(val));
+ if (ret)
+ goto err_ida;
+
+ nvm->major = val >> 16;
+ nvm->minor = val >> 8;
+
+ nvm_dev = register_nvmem(sw, nvm->id, nvm_size, true);
+ if (IS_ERR(nvm_dev)) {
+ ret = PTR_ERR(nvm_dev);
+ goto err_ida;
+ }
+ nvm->active = nvm_dev;
+ }
+
+ nvm_dev = register_nvmem(sw, nvm->id, NVM_MAX_SIZE, false);
+ if (IS_ERR(nvm_dev)) {
+ ret = PTR_ERR(nvm_dev);
+ goto err_nvm_active;
+ }
+ nvm->non_active = nvm_dev;
+
+ mutex_lock(&switch_lock);
+ sw->nvm = nvm;
+ mutex_unlock(&switch_lock);
+
+ return 0;
+
+err_nvm_active:
+ if (nvm->active)
+ nvmem_unregister(nvm->active);
+err_ida:
+ ida_simple_remove(&nvm_ida, nvm->id);
+ kfree(nvm);
+
+ return ret;
+}
+
+static void tb_switch_nvm_remove(struct tb_switch *sw)
+{
+ struct tb_switch_nvm *nvm;
+
+ mutex_lock(&switch_lock);
+ nvm = sw->nvm;
+ sw->nvm = NULL;
+ mutex_unlock(&switch_lock);
+
+ if (!nvm)
+ return;
+
+ /* Remove authentication status in case the switch is unplugged */
+ if (!nvm->authenticating)
+ nvm_clear_auth_status(sw);
+
+ nvmem_unregister(nvm->non_active);
+ if (nvm->active)
+ nvmem_unregister(nvm->active);
+ ida_simple_remove(&nvm_ida, nvm->id);
+ vfree(nvm->buf);
+ kfree(nvm);
+}
+
+/* port utility functions */
+
+static const char *tb_port_type(struct tb_regs_port_header *port)
+{
+ switch (port->type >> 16) {
+ case 0:
+ switch ((u8) port->type) {
+ case 0:
+ return "Inactive";
+ case 1:
+ return "Port";
+ case 2:
+ return "NHI";
+ default:
+ return "unknown";
+ }
+ case 0x2:
+ return "Ethernet";
+ case 0x8:
+ return "SATA";
+ case 0xe:
+ return "DP/HDMI";
+ case 0x10:
+ return "PCIe";
+ case 0x20:
+ return "USB";
+ default:
+ return "unknown";
+ }
+}
+
+static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port)
+{
+ tb_info(tb,
+ " Port %d: %x:%x (Revision: %d, TB Version: %d, Type: %s (%#x))\n",
+ port->port_number, port->vendor_id, port->device_id,
+ port->revision, port->thunderbolt_version, tb_port_type(port),
+ port->type);
+ tb_info(tb, " Max hop id (in/out): %d/%d\n",
+ port->max_in_hop_id, port->max_out_hop_id);
+ tb_info(tb, " Max counters: %d\n", port->max_counters);
+ tb_info(tb, " NFC Credits: %#x\n", port->nfc_credits);
+}
+
+/**
+ * tb_port_state() - get connectedness state of a port
+ *
+ * The port must have a TB_CAP_PHY (i.e. it should be a real port).
+ *
+ * Return: Returns an enum tb_port_state on success or an error code on failure.
+ */
+static int tb_port_state(struct tb_port *port)
+{
+ struct tb_cap_phy phy;
+ int res;
+ if (port->cap_phy == 0) {
+ tb_port_WARN(port, "does not have a PHY\n");
+ return -EINVAL;
+ }
+ res = tb_port_read(port, &phy, TB_CFG_PORT, port->cap_phy, 2);
+ if (res)
+ return res;
+ return phy.state;
+}
+
+/**
+ * tb_wait_for_port() - wait for a port to become ready
+ *
+ * Wait up to 1 second for a port to reach state TB_PORT_UP. If
+ * wait_if_unplugged is set then we also wait if the port is in state
+ * TB_PORT_UNPLUGGED (it takes a while for the device to be registered after
+ * switch resume). Otherwise we only wait if a device is registered but the link
+ * has not yet been established.
+ *
+ * Return: Returns an error code on failure. Returns 0 if the port is not
+ * connected or failed to reach state TB_PORT_UP within one second. Returns 1
+ * if the port is connected and in state TB_PORT_UP.
+ */
+int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged)
+{
+ int retries = 10;
+ int state;
+ if (!port->cap_phy) {
+ tb_port_WARN(port, "does not have PHY\n");
+ return -EINVAL;
+ }
+ if (tb_is_upstream_port(port)) {
+ tb_port_WARN(port, "is the upstream port\n");
+ return -EINVAL;
+ }
+
+ while (retries--) {
+ state = tb_port_state(port);
+ if (state < 0)
+ return state;
+ if (state == TB_PORT_DISABLED) {
+ tb_port_info(port, "is disabled (state: 0)\n");
+ return 0;
+ }
+ if (state == TB_PORT_UNPLUGGED) {
+ if (wait_if_unplugged) {
+ /* used during resume */
+ tb_port_info(port,
+ "is unplugged (state: 7), retrying...\n");
+ msleep(100);
+ continue;
+ }
+ tb_port_info(port, "is unplugged (state: 7)\n");
+ return 0;
+ }
+ if (state == TB_PORT_UP) {
+ tb_port_info(port,
+ "is connected, link is up (state: 2)\n");
+ return 1;
+ }
+
+ /*
+ * After plug-in the state is TB_PORT_CONNECTING. Give it some
+ * time.
+ */
+ tb_port_info(port,
+ "is connected, link is not up (state: %d), retrying...\n",
+ state);
+ msleep(100);
+ }
+ tb_port_warn(port,
+ "failed to reach state TB_PORT_UP. Ignoring port...\n");
+ return 0;
+}
+
+/**
+ * tb_port_add_nfc_credits() - add/remove non flow controlled credits to port
+ *
+ * Change the number of NFC credits allocated to @port by @credits. To remove
+ * NFC credits pass a negative amount of credits.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_port_add_nfc_credits(struct tb_port *port, int credits)
+{
+ if (credits == 0)
+ return 0;
+ tb_port_info(port,
+ "adding %#x NFC credits (%#x -> %#x)",
+ credits,
+ port->config.nfc_credits,
+ port->config.nfc_credits + credits);
+ port->config.nfc_credits += credits;
+ return tb_port_write(port, &port->config.nfc_credits,
+ TB_CFG_PORT, 4, 1);
+}
+
+/**
+ * tb_port_clear_counter() - clear a counter in TB_CFG_COUNTER
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_port_clear_counter(struct tb_port *port, int counter)
+{
+ u32 zero[3] = { 0, 0, 0 };
+ tb_port_info(port, "clearing counter %d\n", counter);
+ return tb_port_write(port, zero, TB_CFG_COUNTERS, 3 * counter, 3);
+}
+
+/**
+ * tb_init_port() - initialize a port
+ *
+ * This is a helper method for tb_switch_alloc. Does not check or initialize
+ * any downstream switches.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+static int tb_init_port(struct tb_port *port)
+{
+ int res;
+ int cap;
+
+ res = tb_port_read(port, &port->config, TB_CFG_PORT, 0, 8);
+ if (res)
+ return res;
+
+ /* Port 0 is the switch itself and has no PHY. */
+ if (port->config.type == TB_TYPE_PORT && port->port != 0) {
+ cap = tb_port_find_cap(port, TB_PORT_CAP_PHY);
+
+ if (cap > 0)
+ port->cap_phy = cap;
+ else
+ tb_port_WARN(port, "non switch port without a PHY\n");
+ }
+
+ tb_dump_port(port->sw->tb, &port->config);
+
+ /* TODO: Read dual link port, DP port and more from EEPROM. */
+ return 0;
+
+}
+
+/* switch utility functions */
+
+static void tb_dump_switch(struct tb *tb, struct tb_regs_switch_header *sw)
+{
+ tb_info(tb,
+ " Switch: %x:%x (Revision: %d, TB Version: %d)\n",
+ sw->vendor_id, sw->device_id, sw->revision,
+ sw->thunderbolt_version);
+ tb_info(tb, " Max Port Number: %d\n", sw->max_port_number);
+ tb_info(tb, " Config:\n");
+ tb_info(tb,
+ " Upstream Port Number: %d Depth: %d Route String: %#llx Enabled: %d, PlugEventsDelay: %dms\n",
+ sw->upstream_port_number, sw->depth,
+ (((u64) sw->route_hi) << 32) | sw->route_lo,
+ sw->enabled, sw->plug_events_delay);
+ tb_info(tb,
+ " unknown1: %#x unknown4: %#x\n",
+ sw->__unknown1, sw->__unknown4);
+}
+
+/**
+ * reset_switch() - reconfigure route, enable and send TB_CFG_PKG_RESET
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_switch_reset(struct tb *tb, u64 route)
+{
+ struct tb_cfg_result res;
+ struct tb_regs_switch_header header = {
+ header.route_hi = route >> 32,
+ header.route_lo = route,
+ header.enabled = true,
+ };
+ tb_info(tb, "resetting switch at %llx\n", route);
+ res.err = tb_cfg_write(tb->ctl, ((u32 *) &header) + 2, route,
+ 0, 2, 2, 2);
+ if (res.err)
+ return res.err;
+ res = tb_cfg_reset(tb->ctl, route, TB_CFG_DEFAULT_TIMEOUT);
+ if (res.err > 0)
+ return -EIO;
+ return res.err;
+}
+
+struct tb_switch *get_switch_at_route(struct tb_switch *sw, u64 route)
+{
+ u8 next_port = route; /*
+ * Routes use a stride of 8 bits,
+ * eventhough a port index has 6 bits at most.
+ * */
+ if (route == 0)
+ return sw;
+ if (next_port > sw->config.max_port_number)
+ return NULL;
+ if (tb_is_upstream_port(&sw->ports[next_port]))
+ return NULL;
+ if (!sw->ports[next_port].remote)
+ return NULL;
+ return get_switch_at_route(sw->ports[next_port].remote->sw,
+ route >> TB_ROUTE_SHIFT);
+}
+
+/**
+ * tb_plug_events_active() - enable/disable plug events on a switch
+ *
+ * Also configures a sane plug_events_delay of 255ms.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+static int tb_plug_events_active(struct tb_switch *sw, bool active)
+{
+ u32 data;
+ int res;
+
+ if (!sw->config.enabled)
+ return 0;
+
+ sw->config.plug_events_delay = 0xff;
+ res = tb_sw_write(sw, ((u32 *) &sw->config) + 4, TB_CFG_SWITCH, 4, 1);
+ if (res)
+ return res;
+
+ res = tb_sw_read(sw, &data, TB_CFG_SWITCH, sw->cap_plug_events + 1, 1);
+ if (res)
+ return res;
+
+ if (active) {
+ data = data & 0xFFFFFF83;
+ switch (sw->config.device_id) {
+ case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
+ case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
+ case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
+ break;
+ default:
+ data |= 4;
+ }
+ } else {
+ data = data | 0x7c;
+ }
+ return tb_sw_write(sw, &data, TB_CFG_SWITCH,
+ sw->cap_plug_events + 1, 1);
+}
+
+static ssize_t authorized_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%u\n", sw->authorized);
+}
+
+static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)
+{
+ int ret = -EINVAL;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ if (sw->authorized)
+ goto unlock;
+
+ /*
+ * Make sure there is no PCIe rescan ongoing when a new PCIe
+ * tunnel is created. Otherwise the PCIe rescan code might find
+ * the new tunnel too early.
+ */
+ pci_lock_rescan_remove();
+
+ switch (val) {
+ /* Approve switch */
+ case 1:
+ if (sw->key)
+ ret = tb_domain_approve_switch_key(sw->tb, sw);
+ else
+ ret = tb_domain_approve_switch(sw->tb, sw);
+ break;
+
+ /* Challenge switch */
+ case 2:
+ if (sw->key)
+ ret = tb_domain_challenge_switch_key(sw->tb, sw);
+ break;
+
+ default:
+ break;
+ }
+
+ pci_unlock_rescan_remove();
+
+ if (!ret) {
+ sw->authorized = val;
+ /* Notify status change to the userspace */
+ kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
+ }
+
+unlock:
+ mutex_unlock(&switch_lock);
+ return ret;
+}
+
+static ssize_t authorized_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ unsigned int val;
+ ssize_t ret;
+
+ ret = kstrtouint(buf, 0, &val);
+ if (ret)
+ return ret;
+ if (val > 2)
+ return -EINVAL;
+
+ ret = tb_switch_set_authorized(sw, val);
+
+ return ret ? ret : count;
+}
+static DEVICE_ATTR_RW(authorized);
+
+static ssize_t device_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%#x\n", sw->device);
+}
+static DEVICE_ATTR_RO(device);
+
+static ssize_t
+device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%s\n", sw->device_name ? sw->device_name : "");
+}
+static DEVICE_ATTR_RO(device_name);
+
+static ssize_t key_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ ssize_t ret;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ if (sw->key)
+ ret = sprintf(buf, "%*phN\n", TB_SWITCH_KEY_SIZE, sw->key);
+ else
+ ret = sprintf(buf, "\n");
+
+ mutex_unlock(&switch_lock);
+ return ret;
+}
+
+static ssize_t key_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ u8 key[TB_SWITCH_KEY_SIZE];
+ ssize_t ret = count;
+ bool clear = false;
+
+ if (!strcmp(buf, "\n"))
+ clear = true;
+ else if (hex2bin(key, buf, sizeof(key)))
+ return -EINVAL;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ if (sw->authorized) {
+ ret = -EBUSY;
+ } else {
+ kfree(sw->key);
+ if (clear) {
+ sw->key = NULL;
+ } else {
+ sw->key = kmemdup(key, sizeof(key), GFP_KERNEL);
+ if (!sw->key)
+ ret = -ENOMEM;
+ }
+ }
+
+ mutex_unlock(&switch_lock);
+ return ret;
+}
+static DEVICE_ATTR(key, 0600, key_show, key_store);
+
+static ssize_t nvm_authenticate_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ u32 status;
+
+ nvm_get_auth_status(sw, &status);
+ return sprintf(buf, "%#x\n", status);
+}
+
+static ssize_t nvm_authenticate_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ bool val;
+ int ret;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ /* If NVMem devices are not yet added */
+ if (!sw->nvm) {
+ ret = -EAGAIN;
+ goto exit_unlock;
+ }
+
+ ret = kstrtobool(buf, &val);
+ if (ret)
+ goto exit_unlock;
+
+ /* Always clear the authentication status */
+ nvm_clear_auth_status(sw);
+
+ if (val) {
+ ret = nvm_validate_and_write(sw);
+ if (ret)
+ goto exit_unlock;
+
+ sw->nvm->authenticating = true;
+
+ if (!tb_route(sw))
+ ret = nvm_authenticate_host(sw);
+ else
+ ret = nvm_authenticate_device(sw);
+ }
+
+exit_unlock:
+ mutex_unlock(&switch_lock);
+
+ if (ret)
+ return ret;
+ return count;
+}
+static DEVICE_ATTR_RW(nvm_authenticate);
+
+static ssize_t nvm_version_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ int ret;
+
+ if (mutex_lock_interruptible(&switch_lock))
+ return -ERESTARTSYS;
+
+ if (sw->safe_mode)
+ ret = -ENODATA;
+ else if (!sw->nvm)
+ ret = -EAGAIN;
+ else
+ ret = sprintf(buf, "%x.%x\n", sw->nvm->major, sw->nvm->minor);
+
+ mutex_unlock(&switch_lock);
+
+ return ret;
+}
+static DEVICE_ATTR_RO(nvm_version);
+
+static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%#x\n", sw->vendor);
+}
+static DEVICE_ATTR_RO(vendor);
+
+static ssize_t
+vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%s\n", sw->vendor_name ? sw->vendor_name : "");
+}
+static DEVICE_ATTR_RO(vendor_name);
+
+static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%pUb\n", sw->uuid);
+}
+static DEVICE_ATTR_RO(unique_id);
+
+static struct attribute *switch_attrs[] = {
+ &dev_attr_authorized.attr,
+ &dev_attr_device.attr,
+ &dev_attr_device_name.attr,
+ &dev_attr_key.attr,
+ &dev_attr_nvm_authenticate.attr,
+ &dev_attr_nvm_version.attr,
+ &dev_attr_vendor.attr,
+ &dev_attr_vendor_name.attr,
+ &dev_attr_unique_id.attr,
+ NULL,
+};
+
+static umode_t switch_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ if (attr == &dev_attr_key.attr) {
+ if (tb_route(sw) &&
+ sw->tb->security_level == TB_SECURITY_SECURE &&
+ sw->security_level == TB_SECURITY_SECURE)
+ return attr->mode;
+ return 0;
+ } else if (attr == &dev_attr_nvm_authenticate.attr ||
+ attr == &dev_attr_nvm_version.attr) {
+ if (sw->dma_port)
+ return attr->mode;
+ return 0;
+ }
+
+ return sw->safe_mode ? 0 : attr->mode;
+}
+
+static struct attribute_group switch_group = {
+ .is_visible = switch_attr_is_visible,
+ .attrs = switch_attrs,
+};
+
+static const struct attribute_group *switch_groups[] = {
+ &switch_group,
+ NULL,
+};
+
+static void tb_switch_release(struct device *dev)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ dma_port_free(sw->dma_port);
+
+ kfree(sw->uuid);
+ kfree(sw->device_name);
+ kfree(sw->vendor_name);
+ kfree(sw->ports);
+ kfree(sw->drom);
+ kfree(sw->key);
+ kfree(sw);
+}
+
+struct device_type tb_switch_type = {
+ .name = "thunderbolt_device",
+ .release = tb_switch_release,
+};
+
+static int tb_switch_get_generation(struct tb_switch *sw)
+{
+ switch (sw->config.device_id) {
+ case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
+ case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
+ case PCI_DEVICE_ID_INTEL_LIGHT_PEAK:
+ case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_2C:
+ case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
+ case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
+ case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_2C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_4C_BRIDGE:
+ return 1;
+
+ case PCI_DEVICE_ID_INTEL_WIN_RIDGE_2C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_BRIDGE:
+ return 2;
+
+ case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_BRIDGE:
+ case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_BRIDGE:
+ return 3;
+
+ default:
+ /*
+ * For unknown switches assume generation to be 1 to be
+ * on the safe side.
+ */
+ tb_sw_warn(sw, "unsupported switch device id %#x\n",
+ sw->config.device_id);
+ return 1;
+ }
+}
+
+/**
+ * tb_switch_alloc() - allocate a switch
+ * @tb: Pointer to the owning domain
+ * @parent: Parent device for this switch
+ * @route: Route string for this switch
+ *
+ * Allocates and initializes a switch. Will not upload configuration to
+ * the switch. For that you need to call tb_switch_configure()
+ * separately. The returned switch should be released by calling
+ * tb_switch_put().
+ *
+ * Return: Pointer to the allocated switch or %NULL in case of failure
+ */
+struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
+ u64 route)
+{
+ int i;
+ int cap;
+ struct tb_switch *sw;
+ int upstream_port = tb_cfg_get_upstream_port(tb->ctl, route);
+ if (upstream_port < 0)
+ return NULL;
+
+ sw = kzalloc(sizeof(*sw), GFP_KERNEL);
+ if (!sw)
+ return NULL;
+
+ sw->tb = tb;
+ if (tb_cfg_read(tb->ctl, &sw->config, route, 0, TB_CFG_SWITCH, 0, 5))
+ goto err_free_sw_ports;
+
+ tb_info(tb, "current switch config:\n");
+ tb_dump_switch(tb, &sw->config);
+
+ /* configure switch */
+ sw->config.upstream_port_number = upstream_port;
+ sw->config.depth = tb_route_length(route);
+ sw->config.route_lo = route;
+ sw->config.route_hi = route >> 32;
+ sw->config.enabled = 0;
+
+ /* initialize ports */
+ sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
+ GFP_KERNEL);
+ if (!sw->ports)
+ goto err_free_sw_ports;
+
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ /* minimum setup for tb_find_cap and tb_drom_read to work */
+ sw->ports[i].sw = sw;
+ sw->ports[i].port = i;
+ }
+
+ sw->generation = tb_switch_get_generation(sw);
+
+ cap = tb_switch_find_vse_cap(sw, TB_VSE_CAP_PLUG_EVENTS);
+ if (cap < 0) {
+ tb_sw_warn(sw, "cannot find TB_VSE_CAP_PLUG_EVENTS aborting\n");
+ goto err_free_sw_ports;
+ }
+ sw->cap_plug_events = cap;
+
+ /* Root switch is always authorized */
+ if (!route)
+ sw->authorized = true;
+
+ device_initialize(&sw->dev);
+ sw->dev.parent = parent;
+ sw->dev.bus = &tb_bus_type;
+ sw->dev.type = &tb_switch_type;
+ sw->dev.groups = switch_groups;
+ dev_set_name(&sw->dev, "%u-%llx", tb->index, tb_route(sw));
+
+ return sw;
+
+err_free_sw_ports:
+ kfree(sw->ports);
+ kfree(sw);
+
+ return NULL;
+}
+
+/**
+ * tb_switch_alloc_safe_mode() - allocate a switch that is in safe mode
+ * @tb: Pointer to the owning domain
+ * @parent: Parent device for this switch
+ * @route: Route string for this switch
+ *
+ * This creates a switch in safe mode. This means the switch pretty much
+ * lacks all capabilities except DMA configuration port before it is
+ * flashed with a valid NVM firmware.
+ *
+ * The returned switch must be released by calling tb_switch_put().
+ *
+ * Return: Pointer to the allocated switch or %NULL in case of failure
+ */
+struct tb_switch *
+tb_switch_alloc_safe_mode(struct tb *tb, struct device *parent, u64 route)
+{
+ struct tb_switch *sw;
+
+ sw = kzalloc(sizeof(*sw), GFP_KERNEL);
+ if (!sw)
+ return NULL;
+
+ sw->tb = tb;
+ sw->config.depth = tb_route_length(route);
+ sw->config.route_hi = upper_32_bits(route);
+ sw->config.route_lo = lower_32_bits(route);
+ sw->safe_mode = true;
+
+ device_initialize(&sw->dev);
+ sw->dev.parent = parent;
+ sw->dev.bus = &tb_bus_type;
+ sw->dev.type = &tb_switch_type;
+ sw->dev.groups = switch_groups;
+ dev_set_name(&sw->dev, "%u-%llx", tb->index, tb_route(sw));
+
+ return sw;
+}
+
+/**
+ * tb_switch_configure() - Uploads configuration to the switch
+ * @sw: Switch to configure
+ *
+ * Call this function before the switch is added to the system. It will
+ * upload configuration to the switch and makes it available for the
+ * connection manager to use.
+ *
+ * Return: %0 in case of success and negative errno in case of failure
+ */
+int tb_switch_configure(struct tb_switch *sw)
+{
+ struct tb *tb = sw->tb;
+ u64 route;
+ int ret;
+
+ route = tb_route(sw);
+ tb_info(tb,
+ "initializing Switch at %#llx (depth: %d, up port: %d)\n",
+ route, tb_route_length(route), sw->config.upstream_port_number);
+
+ if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
+ tb_sw_warn(sw, "unknown switch vendor id %#x\n",
+ sw->config.vendor_id);
+
+ sw->config.enabled = 1;
+
+ /* upload configuration */
+ ret = tb_sw_write(sw, 1 + (u32 *)&sw->config, TB_CFG_SWITCH, 1, 3);
+ if (ret)
+ return ret;
+
+ return tb_plug_events_active(sw, true);
+}
+
+static int tb_switch_set_uuid(struct tb_switch *sw)
+{
+ u32 uuid[4];
+ int cap, ret;
+
+ ret = 0;
+ if (sw->uuid)
+ return ret;
+
+ /*
+ * The newer controllers include fused UUID as part of link
+ * controller specific registers
+ */
+ cap = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
+ if (cap > 0) {
+ ret = tb_sw_read(sw, uuid, TB_CFG_SWITCH, cap + 3, 4);
+ if (ret)
+ return ret;
+ } else {
+ /*
+ * ICM generates UUID based on UID and fills the upper
+ * two words with ones. This is not strictly following
+ * UUID format but we want to be compatible with it so
+ * we do the same here.
+ */
+ uuid[0] = sw->uid & 0xffffffff;
+ uuid[1] = (sw->uid >> 32) & 0xffffffff;
+ uuid[2] = 0xffffffff;
+ uuid[3] = 0xffffffff;
+ }
+
+ sw->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
+ if (!sw->uuid)
+ ret = -ENOMEM;
+ return ret;
+}
+
+static int tb_switch_add_dma_port(struct tb_switch *sw)
+{
+ u32 status;
+ int ret;
+
+ switch (sw->generation) {
+ case 3:
+ break;
+
+ case 2:
+ /* Only root switch can be upgraded */
+ if (tb_route(sw))
+ return 0;
+ break;
+
+ default:
+ /*
+ * DMA port is the only thing available when the switch
+ * is in safe mode.
+ */
+ if (!sw->safe_mode)
+ return 0;
+ break;
+ }
+
+ if (sw->no_nvm_upgrade)
+ return 0;
+
+ sw->dma_port = dma_port_alloc(sw);
+ if (!sw->dma_port)
+ return 0;
+
+ /*
+ * Check status of the previous flash authentication. If there
+ * is one we need to power cycle the switch in any case to make
+ * it functional again.
+ */
+ ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
+ if (ret <= 0)
+ return ret;
+
+ if (status) {
+ tb_sw_info(sw, "switch flash authentication failed\n");
+ ret = tb_switch_set_uuid(sw);
+ if (ret)
+ return ret;
+ nvm_set_auth_status(sw, status);
+ }
+
+ tb_sw_info(sw, "power cycling the switch now\n");
+ dma_port_power_cycle(sw->dma_port);
+
+ /*
+ * We return error here which causes the switch adding failure.
+ * It should appear back after power cycle is complete.
+ */
+ return -ESHUTDOWN;
+}
+
+/**
+ * tb_switch_add() - Add a switch to the domain
+ * @sw: Switch to add
+ *
+ * This is the last step in adding switch to the domain. It will read
+ * identification information from DROM and initializes ports so that
+ * they can be used to connect other switches. The switch will be
+ * exposed to the userspace when this function successfully returns. To
+ * remove and release the switch, call tb_switch_remove().
+ *
+ * Return: %0 in case of success and negative errno in case of failure
+ */
+int tb_switch_add(struct tb_switch *sw)
+{
+ int i, ret;
+
+ /*
+ * Initialize DMA control port now before we read DROM. Recent
+ * host controllers have more complete DROM on NVM that includes
+ * vendor and model identification strings which we then expose
+ * to the userspace. NVM can be accessed through DMA
+ * configuration based mailbox.
+ */
+ ret = tb_switch_add_dma_port(sw);
+ if (ret)
+ return ret;
+
+ if (!sw->safe_mode) {
+ /* read drom */
+ ret = tb_drom_read(sw);
+ if (ret) {
+ tb_sw_warn(sw, "tb_eeprom_read_rom failed\n");
+ return ret;
+ }
+ tb_sw_info(sw, "uid: %#llx\n", sw->uid);
+
+ ret = tb_switch_set_uuid(sw);
+ if (ret)
+ return ret;
+
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ if (sw->ports[i].disabled) {
+ tb_port_info(&sw->ports[i], "disabled by eeprom\n");
+ continue;
+ }
+ ret = tb_init_port(&sw->ports[i]);
+ if (ret)
+ return ret;
+ }
+ }
+
+ ret = device_add(&sw->dev);
+ if (ret)
+ return ret;
+
+ ret = tb_switch_nvm_add(sw);
+ if (ret)
+ device_del(&sw->dev);
+
+ return ret;
+}
+
+/**
+ * tb_switch_remove() - Remove and release a switch
+ * @sw: Switch to remove
+ *
+ * This will remove the switch from the domain and release it after last
+ * reference count drops to zero. If there are switches connected below
+ * this switch, they will be removed as well.
+ */
+void tb_switch_remove(struct tb_switch *sw)
+{
+ int i;
+
+ /* port 0 is the switch itself and never has a remote */
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ if (tb_is_upstream_port(&sw->ports[i]))
+ continue;
+ if (sw->ports[i].remote)
+ tb_switch_remove(sw->ports[i].remote->sw);
+ sw->ports[i].remote = NULL;
+ }
+
+ if (!sw->is_unplugged)
+ tb_plug_events_active(sw, false);
+
+ tb_switch_nvm_remove(sw);
+ device_unregister(&sw->dev);
+}
+
+/**
+ * tb_sw_set_unplugged() - set is_unplugged on switch and downstream switches
+ */
+void tb_sw_set_unplugged(struct tb_switch *sw)
+{
+ int i;
+ if (sw == sw->tb->root_switch) {
+ tb_sw_WARN(sw, "cannot unplug root switch\n");
+ return;
+ }
+ if (sw->is_unplugged) {
+ tb_sw_WARN(sw, "is_unplugged already set\n");
+ return;
+ }
+ sw->is_unplugged = true;
+ for (i = 0; i <= sw->config.max_port_number; i++) {
+ if (!tb_is_upstream_port(&sw->ports[i]) && sw->ports[i].remote)
+ tb_sw_set_unplugged(sw->ports[i].remote->sw);
+ }
+}
+
+int tb_switch_resume(struct tb_switch *sw)
+{
+ int i, err;
+ tb_sw_info(sw, "resuming switch\n");
+
+ /*
+ * Check for UID of the connected switches except for root
+ * switch which we assume cannot be removed.
+ */
+ if (tb_route(sw)) {
+ u64 uid;
+
+ err = tb_drom_read_uid_only(sw, &uid);
+ if (err) {
+ tb_sw_warn(sw, "uid read failed\n");
+ return err;
+ }
+ if (sw->uid != uid) {
+ tb_sw_info(sw,
+ "changed while suspended (uid %#llx -> %#llx)\n",
+ sw->uid, uid);
+ return -ENODEV;
+ }
+ }
+
+ /* upload configuration */
+ err = tb_sw_write(sw, 1 + (u32 *) &sw->config, TB_CFG_SWITCH, 1, 3);
+ if (err)
+ return err;
+
+ err = tb_plug_events_active(sw, true);
+ if (err)
+ return err;
+
+ /* check for surviving downstream switches */
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ struct tb_port *port = &sw->ports[i];
+ if (tb_is_upstream_port(port))
+ continue;
+ if (!port->remote)
+ continue;
+ if (tb_wait_for_port(port, true) <= 0
+ || tb_switch_resume(port->remote->sw)) {
+ tb_port_warn(port,
+ "lost during suspend, disconnecting\n");
+ tb_sw_set_unplugged(port->remote->sw);
+ }
+ }
+ return 0;
+}
+
+void tb_switch_suspend(struct tb_switch *sw)
+{
+ int i, err;
+ err = tb_plug_events_active(sw, false);
+ if (err)
+ return;
+
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ if (!tb_is_upstream_port(&sw->ports[i]) && sw->ports[i].remote)
+ tb_switch_suspend(sw->ports[i].remote->sw);
+ }
+ /*
+ * TODO: invoke tb_cfg_prepare_to_sleep here? does not seem to have any
+ * effect?
+ */
+}
+
+struct tb_sw_lookup {
+ struct tb *tb;
+ u8 link;
+ u8 depth;
+ const uuid_t *uuid;
+};
+
+static int tb_switch_match(struct device *dev, void *data)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+ struct tb_sw_lookup *lookup = data;
+
+ if (!sw)
+ return 0;
+ if (sw->tb != lookup->tb)
+ return 0;
+
+ if (lookup->uuid)
+ return !memcmp(sw->uuid, lookup->uuid, sizeof(*lookup->uuid));
+
+ /* Root switch is matched only by depth */
+ if (!lookup->depth)
+ return !sw->depth;
+
+ return sw->link == lookup->link && sw->depth == lookup->depth;
+}
+
+/**
+ * tb_switch_find_by_link_depth() - Find switch by link and depth
+ * @tb: Domain the switch belongs
+ * @link: Link number the switch is connected
+ * @depth: Depth of the switch in link
+ *
+ * Returned switch has reference count increased so the caller needs to
+ * call tb_switch_put() when done with the switch.
+ */
+struct tb_switch *tb_switch_find_by_link_depth(struct tb *tb, u8 link, u8 depth)
+{
+ struct tb_sw_lookup lookup;
+ struct device *dev;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.tb = tb;
+ lookup.link = link;
+ lookup.depth = depth;
+
+ dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
+ if (dev)
+ return tb_to_switch(dev);
+
+ return NULL;
+}
+
+/**
+ * tb_switch_find_by_link_depth() - Find switch by UUID
+ * @tb: Domain the switch belongs
+ * @uuid: UUID to look for
+ *
+ * Returned switch has reference count increased so the caller needs to
+ * call tb_switch_put() when done with the switch.
+ */
+struct tb_switch *tb_switch_find_by_uuid(struct tb *tb, const uuid_t *uuid)
+{
+ struct tb_sw_lookup lookup;
+ struct device *dev;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.tb = tb;
+ lookup.uuid = uuid;
+
+ dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
+ if (dev)
+ return tb_to_switch(dev);
+
+ return NULL;
+}
+
+void tb_switch_exit(void)
+{
+ ida_destroy(&nvm_ida);
+}