greybus: interface: implement generic mode-switch functionality
[cascardo/linux.git] / drivers / staging / greybus / interface.c
index 0c3613e..b5d243b 100644 (file)
@@ -8,6 +8,404 @@
  */
 
 #include "greybus.h"
+#include "greybus_trace.h"
+
+#define GB_INTERFACE_MODE_SWITCH_TIMEOUT       1000
+
+#define GB_INTERFACE_DEVICE_ID_BAD     0xff
+
+/* Don't-care selector index */
+#define DME_SELECTOR_INDEX_NULL                0
+
+/* DME attributes */
+/* FIXME: remove ES2 support and DME_T_TST_SRC_INCREMENT */
+#define DME_T_TST_SRC_INCREMENT                0x4083
+
+#define DME_DDBL1_MANUFACTURERID       0x5003
+#define DME_DDBL1_PRODUCTID            0x5004
+
+#define DME_TOSHIBA_ARA_VID            0x6000
+#define DME_TOSHIBA_ARA_PID            0x6001
+#define DME_TOSHIBA_ARA_SN0            0x6002
+#define DME_TOSHIBA_ARA_SN1            0x6003
+#define DME_TOSHIBA_ARA_INIT_STATUS    0x6101
+
+/* DDBL1 Manufacturer and Product ids */
+#define TOSHIBA_DMID                   0x0126
+#define TOSHIBA_ES2_BRIDGE_DPID                0x1000
+#define TOSHIBA_ES3_APBRIDGE_DPID      0x1001
+#define TOSHIBA_ES3_GBPHY_DPID 0x1002
+
+
+static int gb_interface_dme_attr_get(struct gb_interface *intf,
+                                                       u16 attr, u32 *val)
+{
+       return gb_svc_dme_peer_get(intf->hd->svc, intf->interface_id,
+                                       attr, DME_SELECTOR_INDEX_NULL, val);
+}
+
+static int gb_interface_read_ara_dme(struct gb_interface *intf)
+{
+       u32 sn0, sn1;
+       int ret;
+
+       /*
+        * Unless this is a Toshiba bridge, bail out until we have defined
+        * standard Ara attributes.
+        */
+       if (intf->ddbl1_manufacturer_id != TOSHIBA_DMID) {
+               dev_err(&intf->dev, "unknown manufacturer %08x\n",
+                               intf->ddbl1_manufacturer_id);
+               return -ENODEV;
+       }
+
+       ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_ARA_VID,
+                                       &intf->vendor_id);
+       if (ret)
+               return ret;
+
+       ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_ARA_PID,
+                                       &intf->product_id);
+       if (ret)
+               return ret;
+
+       ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_ARA_SN0, &sn0);
+       if (ret)
+               return ret;
+
+       ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_ARA_SN1, &sn1);
+       if (ret)
+               return ret;
+
+       intf->serial_number = (u64)sn1 << 32 | sn0;
+
+       return 0;
+}
+
+static int gb_interface_read_dme(struct gb_interface *intf)
+{
+       int ret;
+
+       ret = gb_interface_dme_attr_get(intf, DME_DDBL1_MANUFACTURERID,
+                                       &intf->ddbl1_manufacturer_id);
+       if (ret)
+               return ret;
+
+       ret = gb_interface_dme_attr_get(intf, DME_DDBL1_PRODUCTID,
+                                       &intf->ddbl1_product_id);
+       if (ret)
+               return ret;
+
+       if (intf->ddbl1_manufacturer_id == TOSHIBA_DMID &&
+                       intf->ddbl1_product_id == TOSHIBA_ES2_BRIDGE_DPID) {
+               intf->quirks |= GB_INTERFACE_QUIRK_NO_ARA_IDS;
+               intf->quirks |= GB_INTERFACE_QUIRK_NO_INIT_STATUS;
+       }
+
+       return gb_interface_read_ara_dme(intf);
+}
+
+static int gb_interface_route_create(struct gb_interface *intf)
+{
+       struct gb_svc *svc = intf->hd->svc;
+       u8 intf_id = intf->interface_id;
+       u8 device_id;
+       int ret;
+
+       /* Allocate an interface device id. */
+       ret = ida_simple_get(&svc->device_id_map,
+                            GB_SVC_DEVICE_ID_MIN, GB_SVC_DEVICE_ID_MAX + 1,
+                            GFP_KERNEL);
+       if (ret < 0) {
+               dev_err(&intf->dev, "failed to allocate device id: %d\n", ret);
+               return ret;
+       }
+       device_id = ret;
+
+       ret = gb_svc_intf_device_id(svc, intf_id, device_id);
+       if (ret) {
+               dev_err(&intf->dev, "failed to set device id %u: %d\n",
+                               device_id, ret);
+               goto err_ida_remove;
+       }
+
+       /* FIXME: Hard-coded AP device id. */
+       ret = gb_svc_route_create(svc, svc->ap_intf_id, GB_SVC_DEVICE_ID_AP,
+                                 intf_id, device_id);
+       if (ret) {
+               dev_err(&intf->dev, "failed to create route: %d\n", ret);
+               goto err_svc_id_free;
+       }
+
+       intf->device_id = device_id;
+
+       return 0;
+
+err_svc_id_free:
+       /*
+        * XXX Should we tell SVC that this id doesn't belong to interface
+        * XXX anymore.
+        */
+err_ida_remove:
+       ida_simple_remove(&svc->device_id_map, device_id);
+
+       return ret;
+}
+
+static void gb_interface_route_destroy(struct gb_interface *intf)
+{
+       struct gb_svc *svc = intf->hd->svc;
+
+       if (intf->device_id == GB_INTERFACE_DEVICE_ID_BAD)
+               return;
+
+       gb_svc_route_destroy(svc, svc->ap_intf_id, intf->interface_id);
+       ida_simple_remove(&svc->device_id_map, intf->device_id);
+       intf->device_id = GB_INTERFACE_DEVICE_ID_BAD;
+}
+
+/* Locking: Caller holds the interface mutex. */
+static int gb_interface_legacy_mode_switch(struct gb_interface *intf)
+{
+       int ret;
+
+       dev_info(&intf->dev, "legacy mode switch detected\n");
+
+       /* Mark as disconnected to prevent I/O during disable. */
+       intf->disconnected = true;
+       gb_interface_disable(intf);
+       intf->disconnected = false;
+
+       ret = gb_interface_enable(intf);
+       if (ret) {
+               dev_err(&intf->dev, "failed to re-enable interface: %d\n", ret);
+               gb_interface_deactivate(intf);
+       }
+
+       return ret;
+}
+
+void gb_interface_mailbox_event(struct gb_interface *intf, u16 result,
+                                                               u32 mailbox)
+{
+       mutex_lock(&intf->mutex);
+
+       if (result) {
+               dev_warn(&intf->dev,
+                               "mailbox event with UniPro error: 0x%04x\n",
+                               result);
+               goto err_disable;
+       }
+
+       if (mailbox != GB_SVC_INTF_MAILBOX_GREYBUS) {
+               dev_warn(&intf->dev,
+                               "mailbox event with unexpected value: 0x%08x\n",
+                               mailbox);
+               goto err_disable;
+       }
+
+       if (intf->quirks & GB_INTERFACE_QUIRK_LEGACY_MODE_SWITCH) {
+               gb_interface_legacy_mode_switch(intf);
+               goto out_unlock;
+       }
+
+       if (!intf->mode_switch) {
+               dev_warn(&intf->dev, "unexpected mailbox event: 0x%08x\n",
+                               mailbox);
+               goto err_disable;
+       }
+
+       dev_info(&intf->dev, "mode switch detected\n");
+
+       complete(&intf->mode_switch_completion);
+
+out_unlock:
+       mutex_unlock(&intf->mutex);
+
+       return;
+
+err_disable:
+       gb_interface_disable(intf);
+       gb_interface_deactivate(intf);
+       mutex_unlock(&intf->mutex);
+}
+
+static void gb_interface_mode_switch_work(struct work_struct *work)
+{
+       struct gb_interface *intf;
+       struct gb_control *control;
+       unsigned long timeout;
+       int ret;
+
+       intf = container_of(work, struct gb_interface, mode_switch_work);
+
+       mutex_lock(&intf->mutex);
+       /* Make sure interface is still enabled. */
+       if (!intf->enabled) {
+               dev_dbg(&intf->dev, "mode switch aborted\n");
+               intf->mode_switch = false;
+               mutex_unlock(&intf->mutex);
+               goto out_interface_put;
+       }
+
+       /*
+        * Prepare the control device for mode switch and make sure to get an
+        * extra reference before it goes away during interface disable.
+        */
+       control = gb_control_get(intf->control);
+       gb_control_mode_switch_prepare(control);
+       gb_interface_disable(intf);
+       mutex_unlock(&intf->mutex);
+
+       timeout = msecs_to_jiffies(GB_INTERFACE_MODE_SWITCH_TIMEOUT);
+       ret = wait_for_completion_interruptible_timeout(
+                       &intf->mode_switch_completion, timeout);
+
+       /* Finalise control-connection mode switch. */
+       gb_control_mode_switch_complete(control);
+       gb_control_put(control);
+
+       if (ret < 0) {
+               dev_err(&intf->dev, "mode switch interrupted\n");
+               goto err_deactivate;
+       } else if (ret == 0) {
+               dev_err(&intf->dev, "mode switch timed out\n");
+               goto err_deactivate;
+       }
+
+       /* Re-enable (re-enumerate) interface if still active. */
+       mutex_lock(&intf->mutex);
+       intf->mode_switch = false;
+       if (intf->active) {
+               ret = gb_interface_enable(intf);
+               if (ret) {
+                       dev_err(&intf->dev, "failed to re-enable interface: %d\n",
+                                       ret);
+                       gb_interface_deactivate(intf);
+               }
+       }
+       mutex_unlock(&intf->mutex);
+
+out_interface_put:
+       gb_interface_put(intf);
+
+       return;
+
+err_deactivate:
+       mutex_lock(&intf->mutex);
+       intf->mode_switch = false;
+       gb_interface_deactivate(intf);
+       mutex_unlock(&intf->mutex);
+
+       gb_interface_put(intf);
+}
+
+int gb_interface_request_mode_switch(struct gb_interface *intf)
+{
+       int ret = 0;
+
+       mutex_lock(&intf->mutex);
+       if (intf->mode_switch) {
+               ret = -EBUSY;
+               goto out_unlock;
+       }
+
+       intf->mode_switch = true;
+       reinit_completion(&intf->mode_switch_completion);
+
+       /*
+        * Get a reference to the interface device, which will be put once the
+        * mode switch is complete.
+        */
+       get_device(&intf->dev);
+
+       if (!queue_work(system_long_wq, &intf->mode_switch_work)) {
+               put_device(&intf->dev);
+               ret = -EBUSY;
+               goto out_unlock;
+       }
+
+out_unlock:
+       mutex_unlock(&intf->mutex);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(gb_interface_request_mode_switch);
+
+/*
+ * T_TstSrcIncrement is written by the module on ES2 as a stand-in for the
+ * init-status attribute DME_TOSHIBA_INIT_STATUS. The AP needs to read and
+ * clear it after reading a non-zero value from it.
+ *
+ * FIXME: This is module-hardware dependent and needs to be extended for every
+ * type of module we want to support.
+ */
+static int gb_interface_read_and_clear_init_status(struct gb_interface *intf)
+{
+       struct gb_host_device *hd = intf->hd;
+       unsigned long bootrom_quirks;
+       int ret;
+       u32 value;
+       u16 attr;
+       u8 init_status;
+
+       /*
+        * ES2 bridges use T_TstSrcIncrement for the init status.
+        *
+        * FIXME: Remove ES2 support
+        */
+       if (intf->quirks & GB_INTERFACE_QUIRK_NO_INIT_STATUS)
+               attr = DME_T_TST_SRC_INCREMENT;
+       else
+               attr = DME_TOSHIBA_ARA_INIT_STATUS;
+
+       ret = gb_svc_dme_peer_get(hd->svc, intf->interface_id, attr,
+                                 DME_SELECTOR_INDEX_NULL, &value);
+       if (ret)
+               return ret;
+
+       /*
+        * A nonzero init status indicates the module has finished
+        * initializing.
+        */
+       if (!value) {
+               dev_err(&intf->dev, "invalid init status\n");
+               return -ENODEV;
+       }
+
+       /*
+        * Extract the init status.
+        *
+        * For ES2: We need to check lowest 8 bits of 'value'.
+        * For ES3: We need to check highest 8 bits out of 32 of 'value'.
+        *
+        * FIXME: Remove ES2 support
+        */
+       if (intf->quirks & GB_INTERFACE_QUIRK_NO_INIT_STATUS)
+               init_status = value & 0xff;
+       else
+               init_status = value >> 24;
+
+       /*
+        * Check if the interface is executing the quirky ES3 bootrom that,
+        * for example, requires E2EFC, CSD and CSV to be disabled.
+        */
+       bootrom_quirks = GB_INTERFACE_QUIRK_NO_CPORT_FEATURES |
+                               GB_INTERFACE_QUIRK_FORCED_DISABLE |
+                               GB_INTERFACE_QUIRK_LEGACY_MODE_SWITCH;
+       switch (init_status) {
+       case GB_INIT_BOOTROM_UNIPRO_BOOT_STARTED:
+       case GB_INIT_BOOTROM_FALLBACK_UNIPRO_BOOT_STARTED:
+               intf->quirks |= bootrom_quirks;
+               break;
+       default:
+               intf->quirks &= ~bootrom_quirks;
+       }
+
+       /* Clear the init status. */
+       return gb_svc_dme_peer_set(hd->svc, intf->interface_id, attr,
+                                  DME_SELECTOR_INDEX_NULL, 0);
+}
 
 /* interface sysfs attributes */
 #define gb_interface_attr(field, type)                                 \
@@ -16,50 +414,94 @@ static ssize_t field##_show(struct device *dev,                            \
                            char *buf)                                  \
 {                                                                      \
        struct gb_interface *intf = to_gb_interface(dev);               \
-       return scnprintf(buf, PAGE_SIZE, "%"#type"\n", intf->field);    \
+       return scnprintf(buf, PAGE_SIZE, type"\n", intf->field);        \
 }                                                                      \
 static DEVICE_ATTR_RO(field)
 
-gb_interface_attr(device_id, d);
-gb_interface_attr(vendor, x);
-gb_interface_attr(product, x);
-gb_interface_attr(unique_id, llX);
-gb_interface_attr(vendor_string, s);
-gb_interface_attr(product_string, s);
+gb_interface_attr(ddbl1_manufacturer_id, "0x%08x");
+gb_interface_attr(ddbl1_product_id, "0x%08x");
+gb_interface_attr(interface_id, "%u");
+gb_interface_attr(vendor_id, "0x%08x");
+gb_interface_attr(product_id, "0x%08x");
+gb_interface_attr(serial_number, "0x%016llx");
 
-static struct attribute *interface_attrs[] = {
-       &dev_attr_device_id.attr,
-       &dev_attr_vendor.attr,
-       &dev_attr_product.attr,
-       &dev_attr_unique_id.attr,
-       &dev_attr_vendor_string.attr,
-       &dev_attr_product_string.attr,
-       NULL,
-};
-ATTRIBUTE_GROUPS(interface);
+static ssize_t voltage_now_show(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+       struct gb_interface *intf = to_gb_interface(dev);
+       int ret;
+       u32 measurement;
 
+       ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
+                                           GB_SVC_PWRMON_TYPE_VOL,
+                                           &measurement);
+       if (ret) {
+               dev_err(&intf->dev, "failed to get voltage sample (%d)\n", ret);
+               return ret;
+       }
 
-/* XXX This could be per-host device */
-static DEFINE_SPINLOCK(gb_interfaces_lock);
+       return sprintf(buf, "%u\n", measurement);
+}
+static DEVICE_ATTR_RO(voltage_now);
 
-// FIXME, odds are you don't want to call this function, rework the caller to
-// not need it please.
-struct gb_interface *gb_interface_find(struct greybus_host_device *hd,
-                                      u8 interface_id)
+static ssize_t current_now_show(struct device *dev,
+                               struct device_attribute *attr, char *buf)
 {
-       struct gb_interface *intf;
+       struct gb_interface *intf = to_gb_interface(dev);
+       int ret;
+       u32 measurement;
+
+       ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
+                                           GB_SVC_PWRMON_TYPE_CURR,
+                                           &measurement);
+       if (ret) {
+               dev_err(&intf->dev, "failed to get current sample (%d)\n", ret);
+               return ret;
+       }
+
+       return sprintf(buf, "%u\n", measurement);
+}
+static DEVICE_ATTR_RO(current_now);
 
-       list_for_each_entry(intf, &hd->interfaces, links)
-               if (intf->interface_id == interface_id)
-                       return intf;
+static ssize_t power_now_show(struct device *dev,
+                             struct device_attribute *attr, char *buf)
+{
+       struct gb_interface *intf = to_gb_interface(dev);
+       int ret;
+       u32 measurement;
+
+       ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
+                                           GB_SVC_PWRMON_TYPE_PWR,
+                                           &measurement);
+       if (ret) {
+               dev_err(&intf->dev, "failed to get power sample (%d)\n", ret);
+               return ret;
+       }
 
-       return NULL;
+       return sprintf(buf, "%u\n", measurement);
 }
+static DEVICE_ATTR_RO(power_now);
+
+static struct attribute *interface_attrs[] = {
+       &dev_attr_ddbl1_manufacturer_id.attr,
+       &dev_attr_ddbl1_product_id.attr,
+       &dev_attr_interface_id.attr,
+       &dev_attr_vendor_id.attr,
+       &dev_attr_product_id.attr,
+       &dev_attr_serial_number.attr,
+       &dev_attr_voltage_now.attr,
+       &dev_attr_current_now.attr,
+       &dev_attr_power_now.attr,
+       NULL,
+};
+ATTRIBUTE_GROUPS(interface);
 
 static void gb_interface_release(struct device *dev)
 {
        struct gb_interface *intf = to_gb_interface(dev);
 
+       trace_gb_interface_release(intf);
+
        kfree(intf);
 }
 
@@ -68,46 +510,6 @@ struct device_type greybus_interface_type = {
        .release =      gb_interface_release,
 };
 
-/*
- * Create kernel structures corresponding to a bundle and connection for
- * managing control/svc CPort.
- */
-int gb_create_bundle_connection(struct gb_interface *intf, u8 class)
-{
-       struct gb_bundle *bundle;
-       u32 ida_start, ida_end;
-       u8 bundle_id, protocol_id;
-       u16 cport_id;
-
-       if (class == GREYBUS_CLASS_CONTROL) {
-               protocol_id = GREYBUS_PROTOCOL_CONTROL;
-               bundle_id = GB_CONTROL_BUNDLE_ID;
-               cport_id = GB_CONTROL_CPORT_ID;
-               ida_start = 0;
-               ida_end = CPORT_ID_MAX;
-       } else if (class == GREYBUS_CLASS_SVC) {
-               protocol_id = GREYBUS_PROTOCOL_SVC;
-               bundle_id = GB_SVC_BUNDLE_ID;
-               cport_id = GB_SVC_CPORT_ID;
-               ida_start = GB_SVC_CPORT_ID;
-               ida_end = GB_SVC_CPORT_ID + 1;
-       } else {
-               WARN_ON(1);
-               return -EINVAL;
-       }
-
-       bundle = gb_bundle_create(intf, bundle_id, class);
-       if (!bundle)
-               return -EINVAL;
-
-       if (!gb_connection_create_range(bundle->intf->hd, bundle, &bundle->dev,
-                                       cport_id, protocol_id, ida_start,
-                                       ida_end))
-               return -EINVAL;
-
-       return 0;
-}
-
 /*
  * A Greybus module represents a user-replaceable component on an Ara
  * phone.  An interface is the physical connection on that module.  A
@@ -120,134 +522,268 @@ int gb_create_bundle_connection(struct gb_interface *intf, u8 class)
  * Returns a pointer to the new interfce or a null pointer if a
  * failure occurs due to memory exhaustion.
  */
-struct gb_interface *gb_interface_create(struct greybus_host_device *hd,
+struct gb_interface *gb_interface_create(struct gb_module *module,
                                         u8 interface_id)
 {
-       struct gb_module *module;
+       struct gb_host_device *hd = module->hd;
        struct gb_interface *intf;
-       int retval;
-
-       intf = gb_interface_find(hd, interface_id);
-       if (intf) {
-               dev_err(hd->parent, "Duplicate interface with interface-id: %d will not be created\n",
-                       interface_id);
-               return NULL;
-       }
-
-       module = gb_module_find(hd, endo_get_module_id(hd->endo, interface_id));
-       if (!module)
-               return NULL;
 
        intf = kzalloc(sizeof(*intf), GFP_KERNEL);
        if (!intf)
-               goto put_module;
+               return NULL;
 
        intf->hd = hd;          /* XXX refcount? */
        intf->module = module;
        intf->interface_id = interface_id;
        INIT_LIST_HEAD(&intf->bundles);
        INIT_LIST_HEAD(&intf->manifest_descs);
+       mutex_init(&intf->mutex);
+       INIT_WORK(&intf->mode_switch_work, gb_interface_mode_switch_work);
+       init_completion(&intf->mode_switch_completion);
 
        /* Invalid device id to start with */
-       intf->device_id = GB_DEVICE_ID_BAD;
+       intf->device_id = GB_INTERFACE_DEVICE_ID_BAD;
 
        intf->dev.parent = &module->dev;
        intf->dev.bus = &greybus_bus_type;
        intf->dev.type = &greybus_interface_type;
        intf->dev.groups = interface_groups;
-       intf->dev.dma_mask = hd->parent->dma_mask;
+       intf->dev.dma_mask = module->dev.dma_mask;
        device_initialize(&intf->dev);
-       dev_set_name(&intf->dev, "%s:%d", dev_name(&module->dev), interface_id);
+       dev_set_name(&intf->dev, "%s.%u", dev_name(&module->dev),
+                       interface_id);
+
+       trace_gb_interface_create(intf);
+
+       return intf;
+}
+
+static int gb_interface_vsys_set(struct gb_interface *intf, bool enable)
+{
+       struct gb_svc *svc = intf->hd->svc;
+       int ret;
+
+       dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
 
-       retval = device_add(&intf->dev);
-       if (retval) {
-               pr_err("failed to add interface device for id 0x%02hhx\n",
-                      interface_id);
-               goto free_intf;
+       ret = gb_svc_intf_vsys_set(svc, intf->interface_id, enable);
+       if (ret) {
+               dev_err(&intf->dev, "failed to set v_sys: %d\n", ret);
+               return ret;
        }
 
-       spin_lock_irq(&gb_interfaces_lock);
-       list_add(&intf->links, &hd->interfaces);
-       spin_unlock_irq(&gb_interfaces_lock);
+       return 0;
+}
 
-       return intf;
+static int gb_interface_refclk_set(struct gb_interface *intf, bool enable)
+{
+       struct gb_svc *svc = intf->hd->svc;
+       int ret;
 
-free_intf:
-       put_device(&intf->dev);
-       kfree(intf);
-put_module:
-       put_device(&module->dev);
-       return NULL;
+       dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
+
+       ret = gb_svc_intf_refclk_set(svc, intf->interface_id, enable);
+       if (ret) {
+               dev_err(&intf->dev, "failed to set refclk: %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int gb_interface_unipro_set(struct gb_interface *intf, bool enable)
+{
+       struct gb_svc *svc = intf->hd->svc;
+       int ret;
+
+       dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
+
+       ret = gb_svc_intf_unipro_set(svc, intf->interface_id, enable);
+       if (ret) {
+               dev_err(&intf->dev, "failed to set UniPro: %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int gb_interface_activate_operation(struct gb_interface *intf)
+{
+       struct gb_svc *svc = intf->hd->svc;
+       u8 type;
+       int ret;
+
+       dev_dbg(&intf->dev, "%s\n", __func__);
+
+       ret = gb_svc_intf_activate(svc, intf->interface_id, &type);
+       if (ret) {
+               dev_err(&intf->dev, "failed to activate: %d\n", ret);
+               return ret;
+       }
+
+       switch (type) {
+       case GB_SVC_INTF_TYPE_DUMMY:
+               dev_info(&intf->dev, "dummy interface detected\n");
+               /* FIXME: handle as an error for now */
+               return -ENODEV;
+       case GB_SVC_INTF_TYPE_UNIPRO:
+               dev_err(&intf->dev, "interface type UniPro not supported\n");
+               /* FIXME: check if this is a Toshiba bridge before retrying? */
+               return -EAGAIN;
+       case GB_SVC_INTF_TYPE_GREYBUS:
+               break;
+       default:
+               dev_err(&intf->dev, "unknown interface type: %u\n", type);
+               return -ENODEV;
+       }
+
+       return 0;
+}
+
+static int gb_interface_hibernate_link(struct gb_interface *intf)
+{
+       dev_dbg(&intf->dev, "%s\n", __func__);
+
+       /* FIXME: implement */
+
+       return 0;
 }
 
 /*
- * Tear down a previously set up module.
+ * Activate an interface.
+ *
+ * Locking: Caller holds the interface mutex.
  */
-static void interface_destroy(struct gb_interface *intf)
+int gb_interface_activate(struct gb_interface *intf)
 {
-       struct gb_module *module;
-       struct gb_bundle *bundle;
-       struct gb_bundle *next;
+       int ret;
+
+       if (intf->ejected)
+               return -ENODEV;
+
+       ret = gb_interface_vsys_set(intf, true);
+       if (ret)
+               return ret;
+
+       ret = gb_interface_refclk_set(intf, true);
+       if (ret)
+               goto err_vsys_disable;
+
+       ret = gb_interface_unipro_set(intf, true);
+       if (ret)
+               goto err_refclk_disable;
+
+       ret = gb_interface_activate_operation(intf);
+       if (ret)
+               goto err_unipro_disable;
+
+       ret = gb_interface_read_dme(intf);
+       if (ret)
+               goto err_hibernate_link;
+
+       ret = gb_interface_route_create(intf);
+       if (ret)
+               goto err_hibernate_link;
+
+       intf->active = true;
+
+       trace_gb_interface_activate(intf);
+
+       return 0;
+
+err_hibernate_link:
+       gb_interface_hibernate_link(intf);
+err_unipro_disable:
+       gb_interface_unipro_set(intf, false);
+err_refclk_disable:
+       gb_interface_refclk_set(intf, false);
+err_vsys_disable:
+       gb_interface_vsys_set(intf, false);
+
+       return ret;
+}
 
-       if (WARN_ON(!intf))
+/*
+ * Deactivate an interface.
+ *
+ * Locking: Caller holds the interface mutex.
+ */
+void gb_interface_deactivate(struct gb_interface *intf)
+{
+       if (!intf->active)
                return;
 
-       spin_lock_irq(&gb_interfaces_lock);
-       list_del(&intf->links);
-       spin_unlock_irq(&gb_interfaces_lock);
+       trace_gb_interface_deactivate(intf);
 
-       list_for_each_entry_safe(bundle, next, &intf->bundles, links)
-               gb_bundle_destroy(bundle);
+       /* Abort any ongoing mode switch. */
+       if (intf->mode_switch)
+               complete(&intf->mode_switch_completion);
 
-       kfree(intf->product_string);
-       kfree(intf->vendor_string);
+       gb_interface_route_destroy(intf);
+       gb_interface_hibernate_link(intf);
+       gb_interface_unipro_set(intf, false);
+       gb_interface_refclk_set(intf, false);
+       gb_interface_vsys_set(intf, false);
 
-       module = intf->module;
-       device_unregister(&intf->dev);
-       put_device(&module->dev);
+       intf->active = false;
 }
 
-/**
- * gb_interface_init
+/*
+ * Enable an interface by enabling its control connection, fetching the
+ * manifest and other information over it, and finally registering its child
+ * devices.
  *
- * Create connection for control CPort and then request/parse manifest.
- * Finally initialize all the bundles to set routes via SVC and initialize all
- * connections.
+ * Locking: Caller holds the interface mutex.
  */
-int gb_interface_init(struct gb_interface *intf, u8 device_id)
+int gb_interface_enable(struct gb_interface *intf)
 {
+       struct gb_control *control;
+       struct gb_bundle *bundle, *tmp;
        int ret, size;
        void *manifest;
 
-       intf->device_id = device_id;
-
-       /* Establish control CPort connection */
-       ret = gb_create_bundle_connection(intf, GREYBUS_CLASS_CONTROL);
+       ret = gb_interface_read_and_clear_init_status(intf);
        if (ret) {
-               dev_err(&intf->dev, "Failed to create control CPort connection (%d)\n", ret);
+               dev_err(&intf->dev, "failed to clear init status: %d\n", ret);
                return ret;
        }
 
+       /* Establish control connection */
+       control = gb_control_create(intf);
+       if (IS_ERR(control)) {
+               dev_err(&intf->dev, "failed to create control device: %ld\n",
+                               PTR_ERR(control));
+               return PTR_ERR(control);
+       }
+       intf->control = control;
+
+       ret = gb_control_enable(intf->control);
+       if (ret)
+               goto err_put_control;
+
        /* Get manifest size using control protocol on CPort */
        size = gb_control_get_manifest_size_operation(intf);
        if (size <= 0) {
-               dev_err(&intf->dev, "%s: Failed to get manifest size (%d)\n",
-                       __func__, size);
+               dev_err(&intf->dev, "failed to get manifest size: %d\n", size);
+
                if (size)
-                       return size;
+                       ret = size;
                else
-                       return -EINVAL;
+                       ret =  -EINVAL;
+
+               goto err_disable_control;
        }
 
        manifest = kmalloc(size, GFP_KERNEL);
-       if (!manifest)
-               return -ENOMEM;
+       if (!manifest) {
+               ret = -ENOMEM;
+               goto err_disable_control;
+       }
 
        /* Get manifest using control protocol on CPort */
        ret = gb_control_get_manifest_operation(intf, manifest, size);
        if (ret) {
-               dev_err(&intf->dev, "%s: Failed to get manifest\n", __func__);
-               goto free_manifest;
+               dev_err(&intf->dev, "failed to get manifest: %d\n", ret);
+               goto err_free_manifest;
        }
 
        /*
@@ -255,40 +791,113 @@ int gb_interface_init(struct gb_interface *intf, u8 device_id)
         * what's in it.
         */
        if (!gb_manifest_parse(intf, manifest, size)) {
-               dev_err(&intf->dev, "%s: Failed to parse manifest\n", __func__);
+               dev_err(&intf->dev, "failed to parse manifest\n");
                ret = -EINVAL;
-               goto free_manifest;
+               goto err_destroy_bundles;
        }
 
-       /*
-        * XXX
-        * We've successfully parsed the manifest.  Now we need to
-        * allocate CPort Id's for connecting to the CPorts found on
-        * other modules.  For each of these, establish a connection
-        * between the local and remote CPorts (including
-        * configuring the switch to allow them to communicate).
-        */
+       ret = gb_control_get_bundle_versions(intf->control);
+       if (ret)
+               goto err_destroy_bundles;
+
+       /* Register the control device and any bundles */
+       ret = gb_control_add(intf->control);
+       if (ret)
+               goto err_destroy_bundles;
+
+       list_for_each_entry_safe_reverse(bundle, tmp, &intf->bundles, links) {
+               ret = gb_bundle_add(bundle);
+               if (ret) {
+                       gb_bundle_destroy(bundle);
+                       continue;
+               }
+       }
 
-free_manifest:
        kfree(manifest);
+
+       intf->enabled = true;
+
+       trace_gb_interface_enable(intf);
+
+       return 0;
+
+err_destroy_bundles:
+       list_for_each_entry_safe(bundle, tmp, &intf->bundles, links)
+               gb_bundle_destroy(bundle);
+err_free_manifest:
+       kfree(manifest);
+err_disable_control:
+       gb_control_disable(intf->control);
+err_put_control:
+       gb_control_put(intf->control);
+       intf->control = NULL;
+
        return ret;
 }
 
-void gb_interface_remove(struct greybus_host_device *hd, u8 interface_id)
+/*
+ * Disable an interface and destroy its bundles.
+ *
+ * Locking: Caller holds the interface mutex.
+ */
+void gb_interface_disable(struct gb_interface *intf)
 {
-       struct gb_interface *intf = gb_interface_find(hd, interface_id);
+       struct gb_bundle *bundle;
+       struct gb_bundle *next;
 
-       if (intf)
-               interface_destroy(intf);
-       else
-               dev_err(hd->parent, "interface id %d not found\n",
-                       interface_id);
+       if (!intf->enabled)
+               return;
+
+       trace_gb_interface_disable(intf);
+
+       /* Set disconnected flag to avoid I/O during connection tear down. */
+       if (intf->quirks & GB_INTERFACE_QUIRK_FORCED_DISABLE)
+               intf->disconnected = true;
+
+       list_for_each_entry_safe(bundle, next, &intf->bundles, links)
+               gb_bundle_destroy(bundle);
+
+       gb_control_del(intf->control);
+       gb_control_disable(intf->control);
+       gb_control_put(intf->control);
+       intf->control = NULL;
+
+       intf->enabled = false;
 }
 
-void gb_interfaces_remove(struct greybus_host_device *hd)
+/* Register an interface. */
+int gb_interface_add(struct gb_interface *intf)
 {
-       struct gb_interface *intf, *temp;
+       int ret;
+
+       ret = device_add(&intf->dev);
+       if (ret) {
+               dev_err(&intf->dev, "failed to register interface: %d\n", ret);
+               return ret;
+       }
+
+       trace_gb_interface_add(intf);
 
-       list_for_each_entry_safe(intf, temp, &hd->interfaces, links)
-               interface_destroy(intf);
+       dev_info(&intf->dev, "Interface added: VID=0x%08x, PID=0x%08x\n",
+                intf->vendor_id, intf->product_id);
+       dev_info(&intf->dev, "DDBL1 Manufacturer=0x%08x, Product=0x%08x\n",
+                intf->ddbl1_manufacturer_id, intf->ddbl1_product_id);
+
+       return 0;
+}
+
+/* Deregister an interface. */
+void gb_interface_del(struct gb_interface *intf)
+{
+       if (device_is_registered(&intf->dev)) {
+               trace_gb_interface_del(intf);
+
+               device_del(&intf->dev);
+               dev_info(&intf->dev, "Interface removed\n");
+       }
+}
+
+void gb_interface_put(struct gb_interface *intf)
+{
+       put_device(&intf->dev);
 }