thunderbolt: Explicitly enable lane adapter hotplug events at startup

commit 5d2569cb4a65c373896ec0217febdf88739ed295 upstream.

Software that has run before the USB4 CM in Linux runs may have disabled
hotplug events for a given lane adapter.

Other CMs such as that one distributed with Windows 11 will enable hotplug
events. Do the same thing in the Linux CM which fixes hotplug events on
"AMD Pink Sardine".

Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 0508da6f63d9e9a759e2de26e63ec3fcc47a3790..744a274d108b0abe923b1aeacbe85c3e49d20b94 100644 (file)
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2822,6 +2822,26 @@ static void tb_switch_credits_init(struct tb_switch *sw)
                tb_sw_info(sw, "failed to determine preferred buffer allocation, using defaults\n");
 }
 
+static int tb_switch_port_hotplug_enable(struct tb_switch *sw)
+{
+       struct tb_port *port;
+
+       if (tb_switch_is_icm(sw))
+               return 0;
+
+       tb_switch_for_each_port(sw, port) {
+               int res;
+
+               if (!port->cap_usb4)
+                       continue;
+
+               res = usb4_port_hotplug_enable(port);
+               if (res)
+                       return res;
+       }
+       return 0;
+}
+
 /**
  * tb_switch_add() - Add a switch to the domain
  * @sw: Switch to add
@@ -2891,6 +2911,10 @@ int tb_switch_add(struct tb_switch *sw)
                        return ret;
        }
 
+       ret = tb_switch_port_hotplug_enable(sw);
+       if (ret)
+               return ret;
+
        ret = device_add(&sw->dev);
        if (ret) {
                dev_err(&sw->dev, "failed to add device: %d\n", ret);

diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 4602c69913fa0d9914c50246dfd5ff1f384988ef..eef6336bd166346fe8b5081bc5286eedc2bd1d9d 100644 (file)
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -1170,6 +1170,7 @@ int usb4_switch_add_ports(struct tb_switch *sw);
 void usb4_switch_remove_ports(struct tb_switch *sw);
 
 int usb4_port_unlock(struct tb_port *port);
+int usb4_port_hotplug_enable(struct tb_port *port);
 int usb4_port_configure(struct tb_port *port);
 void usb4_port_unconfigure(struct tb_port *port);
 int usb4_port_configure_xdomain(struct tb_port *port);

diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
index 6a16f61a72a1b1b478bf751ce40fbaa3fb7b6784..4e0c2a1ccab0cfc9b89f1fc13ace9815bdfcca80 100644 (file)
--- a/drivers/thunderbolt/tb_regs.h
+++ b/drivers/thunderbolt/tb_regs.h
@@ -302,6 +302,7 @@ struct tb_regs_port_header {
 #define ADP_CS_5                               0x05
 #define ADP_CS_5_LCA_MASK                      GENMASK(28, 22)
 #define ADP_CS_5_LCA_SHIFT                     22
+#define ADP_CS_5_DHP                           BIT(31)
 
 /* TMU adapter registers */
 #define TMU_ADP_CS_3                           0x03

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 3a2e7126db9dc894b65b5a92642b9a0cd0a895bd..f0b5a8f1ed3a3c39dd6ccbb39d681690421774df 100644 (file)
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1046,6 +1046,26 @@ int usb4_port_unlock(struct tb_port *port)
        return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_4, 1);
 }
 
+/**
+ * usb4_port_hotplug_enable() - Enables hotplug for a port
+ * @port: USB4 port to operate on
+ *
+ * Enables hot plug events on a given port. This is only intended
+ * to be used on lane, DP-IN, and DP-OUT adapters.
+ */
+int usb4_port_hotplug_enable(struct tb_port *port)
+{
+       int ret;
+       u32 val;
+
+       ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_5, 1);
+       if (ret)
+               return ret;
+
+       val &= ~ADP_CS_5_DHP;
+       return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_5, 1);
+}
+
 static int usb4_port_set_configured(struct tb_port *port, bool configured)
 {
        int ret;