4 files changed, 183 insertions, 0 deletions

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index d2b9ce857818..346b41e7d5d1 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -7,6 +7,7 @@
  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
  */
 
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
 #include <linux/pci.h>
@@ -492,6 +493,22 @@ static irqreturn_t nhi_msi(int irq, void *data)
         return IRQ_HANDLED;
 }
 
+static int nhi_suspend_noirq(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct tb *tb = pci_get_drvdata(pdev);
+        thunderbolt_suspend(tb);
+        return 0;
+}
+
+static int nhi_resume_noirq(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct tb *tb = pci_get_drvdata(pdev);
+        thunderbolt_resume(tb);
+        return 0;
+}
+
 static void nhi_shutdown(struct tb_nhi *nhi)
 {
         int i;
@@ -600,6 +617,21 @@ static void nhi_remove(struct pci_dev *pdev)
         nhi_shutdown(nhi);
 }
 
+/*
+ * The tunneled pci bridges are siblings of us. Use resume_noirq to reenable
+ * the tunnels asap. A corresponding pci quirk blocks the downstream bridges
+ * resume_noirq until we are done.
+ */
+static const struct dev_pm_ops nhi_pm_ops = {
+        .suspend_noirq = nhi_suspend_noirq,
+        .resume_noirq = nhi_resume_noirq,
+        .freeze_noirq = nhi_suspend_noirq, /*
+                                            * we just disable hotplug, the
+                                            * pci-tunnels stay alive.
+                                            */
+        .restore_noirq = nhi_resume_noirq,
+};
+
 struct pci_device_id nhi_ids[] = {
         /*
          * We have to specify class, the TB bridges use the same device and
@@ -626,6 +658,7 @@ static struct pci_driver nhi_driver = {
         .id_table = nhi_ids,
         .probe = nhi_probe,
         .remove = nhi_remove,
+        .driver.pm = &nhi_pm_ops,
 };
 
 static int __init nhi_init(void)
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index aeb5c30f8d76..c2a24b6fb883 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -229,6 +229,30 @@ static void tb_dump_switch(struct tb *tb, struct tb_regs_switch_header *sw)
                 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; /*
@@ -412,3 +436,63 @@ void tb_sw_set_unpplugged(struct tb_switch *sw)
         }
 }
 
+int tb_switch_resume(struct tb_switch *sw)
+{
+        int i, err;
+        u64 uid;
+        tb_sw_info(sw, "resuming switch\n");
+
+        err = tb_eeprom_read_uid(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_unpplugged(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?
+         */
+}
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 177f61df464d..1aa6dd7dc68b 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -69,6 +69,28 @@ static void tb_free_invalid_tunnels(struct tb *tb)
 }
 
 /**
+ * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
+ */
+static void tb_free_unplugged_children(struct tb_switch *sw)
+{
+        int i;
+        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 (port->remote->sw->is_unplugged) {
+                        tb_switch_free(port->remote->sw);
+                        port->remote = NULL;
+                } else {
+                        tb_free_unplugged_children(port->remote->sw);
+                }
+        }
+}
+
+
+/**
  * find_pci_up_port() - return the first PCIe up port on @sw or NULL
  */
 static struct tb_port *tb_find_pci_up_port(struct tb_switch *sw)
@@ -368,3 +390,42 @@ err_locked:
         return NULL;
 }
 
+void thunderbolt_suspend(struct tb *tb)
+{
+        tb_info(tb, "suspending...\n");
+        mutex_lock(&tb->lock);
+        tb_switch_suspend(tb->root_switch);
+        tb_ctl_stop(tb->ctl);
+        tb->hotplug_active = false; /* signal tb_handle_hotplug to quit */
+        mutex_unlock(&tb->lock);
+        tb_info(tb, "suspend finished\n");
+}
+
+void thunderbolt_resume(struct tb *tb)
+{
+        struct tb_pci_tunnel *tunnel, *n;
+        tb_info(tb, "resuming...\n");
+        mutex_lock(&tb->lock);
+        tb_ctl_start(tb->ctl);
+
+        /* remove any pci devices the firmware might have setup */
+        tb_switch_reset(tb, 0);
+
+        tb_switch_resume(tb->root_switch);
+        tb_free_invalid_tunnels(tb);
+        tb_free_unplugged_children(tb->root_switch);
+        list_for_each_entry_safe(tunnel, n, &tb->tunnel_list, list)
+                tb_pci_restart(tunnel);
+        if (!list_empty(&tb->tunnel_list)) {
+                /*
+                 * the pcie links need some time to get going.
+                 * 100ms works for me...
+                 */
+                tb_info(tb, "tunnels restarted, sleeping for 100ms\n");
+                msleep(100);
+        }
+         /* Allow tb_handle_hotplug to progress events */
+        tb->hotplug_active = true;
+        mutex_unlock(&tb->lock);
+        tb_info(tb, "resume finished\n");
+}
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index a89087f2da71..63e89d01047c 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -214,9 +214,14 @@ static inline int tb_port_write(struct tb_port *port, void *buffer,
 
 struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi);
 void thunderbolt_shutdown_and_free(struct tb *tb);
+void thunderbolt_suspend(struct tb *tb);
+void thunderbolt_resume(struct tb *tb);
 
 struct tb_switch *tb_switch_alloc(struct tb *tb, u64 route);
 void tb_switch_free(struct tb_switch *sw);
+void tb_switch_suspend(struct tb_switch *sw);
+int tb_switch_resume(struct tb_switch *sw);
+int tb_switch_reset(struct tb *tb, u64 route);
 void tb_sw_set_unpplugged(struct tb_switch *sw);
 struct tb_switch *get_switch_at_route(struct tb_switch *sw, u64 route);