thunderbolt: Make tb_switch_clx_disable() return CL states that were enabled

This allows us to disable all CL states temporarily when running lane
margining and then return back the previously enabled states.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

diff --git a/drivers/thunderbolt/clx.c b/drivers/thunderbolt/clx.c
index 960409df4405a73de4b4524a3675decf613a32a8..4f0cfbb24dd998b9185d95751f4736d9571f5442 100644 (file)
--- a/drivers/thunderbolt/clx.c
+++ b/drivers/thunderbolt/clx.c
@@ -317,6 +317,9 @@ int tb_switch_clx_enable(struct tb_switch *sw, unsigned int clx)
        struct tb_port *up, *down;
        int ret;
 
+       if (!clx)
+               return 0;
+
        if (!validate_mask(clx))
                return -EINVAL;
 
@@ -380,7 +383,8 @@ int tb_switch_clx_enable(struct tb_switch *sw, unsigned int clx)
  * Disables all CL states of the given router. Can be called on any
  * router and if the states were not enabled already does nothing.
  *
- * Returns %0 on success or an error code on failure.
+ * Returns the CL states that were disabled or negative errno in case of
+ * failure.
  */
 int tb_switch_clx_disable(struct tb_switch *sw)
 {
@@ -408,5 +412,5 @@ int tb_switch_clx_disable(struct tb_switch *sw)
        sw->clx = 0;
 
        tb_sw_dbg(sw, "CLx: %s disabled\n", clx_name(clx));
-       return 0;
+       return clx;
 }

diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
index e376ad25bf60a142c4edabba92c440e97aa47fd7..40b59e662ee3e3a8c19f7d84b5be98e280782219 100644 (file)
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -553,8 +553,9 @@ static int margining_run_write(void *data, u64 val)
        struct usb4_port *usb4 = port->usb4;
        struct tb_switch *sw = port->sw;
        struct tb_margining *margining;
+       struct tb_switch *down_sw;
        struct tb *tb = sw->tb;
-       int ret;
+       int ret, clx;
 
        if (val != 1)
                return -EINVAL;
@@ -566,15 +567,24 @@ static int margining_run_write(void *data, u64 val)
                goto out_rpm_put;
        }
 
-       /*
-        * CL states may interfere with lane margining so inform the user know
-        * and bail out.
-        */
-       if (tb_port_clx_is_enabled(port, TB_CL1 | TB_CL2)) {
-               tb_port_warn(port,
-                            "CL states are enabled, Disable them with clx=0 and re-connect\n");
-               ret = -EINVAL;
-               goto out_unlock;
+       if (tb_is_upstream_port(port))
+               down_sw = sw;
+       else if (port->remote)
+               down_sw = port->remote->sw;
+       else
+               down_sw = NULL;
+
+       if (down_sw) {
+               /*
+                * CL states may interfere with lane margining so
+                * disable them temporarily now.
+                */
+               ret = tb_switch_clx_disable(down_sw);
+               if (ret < 0) {
+                       tb_sw_warn(down_sw, "failed to disable CL states\n");
+                       goto out_unlock;
+               }
+               clx = ret;
        }
 
        margining = usb4->margining;
@@ -586,7 +596,7 @@ static int margining_run_write(void *data, u64 val)
                                          margining->right_high,
                                          USB4_MARGIN_SW_COUNTER_CLEAR);
                if (ret)
-                       goto out_unlock;
+                       goto out_clx;
 
                ret = usb4_port_sw_margin_errors(port, &margining->results[0]);
        } else {
@@ -600,6 +610,9 @@ static int margining_run_write(void *data, u64 val)
                                          margining->right_high, margining->results);
        }
 
+out_clx:
+       if (down_sw)
+               tb_switch_clx_enable(down_sw, clx);
 out_unlock:
        mutex_unlock(&tb->lock);
 out_rpm_put: