thunderbolt: Add missing UNSET_INBOUND_SBTX for retimer access

commit cd0c1e582b055dea615001b8bd8eccaf6f69f7ce upstream.

According to USB4 retimer specification, the process of firmware update
sequence requires issuing a SET_INBOUND_SBTX port operation that later
shall be followed by UNSET_INBOUND_SBTX port operation. This last step
is not currently issued by the driver but it is necessary to make sure
the retimers are put back to passthrough mode even during enumeration.

If this step is missing the link may not come up properly after
soft-reboot for example.

For this reason issue UNSET_INBOUND_SBTX after SET_INBOUND_SBTX for
enumeration and also when the NVM upgrade is run.

Reported-by: Christian Schaubschläger <christian.schaubschlaeger@gmx.at>
Link: https://lore.kernel.org/linux-usb/b556f5ed-5ee8-9990-9910-afd60db93310@gmx.at/
Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.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/retimer.c b/drivers/thunderbolt/retimer.c
index 722694052f4a86d9d4bea58c0d1c28dc641db892..566c03105fb8d65fb20279ef2efde1e597c64183 100644 (file)
--- a/drivers/thunderbolt/retimer.c
+++ b/drivers/thunderbolt/retimer.c
@@ -208,6 +208,22 @@ static ssize_t nvm_authenticate_show(struct device *dev,
        return ret;
 }
 
+static void tb_retimer_set_inbound_sbtx(struct tb_port *port)
+{
+       int i;
+
+       for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
+               usb4_port_retimer_set_inbound_sbtx(port, i);
+}
+
+static void tb_retimer_unset_inbound_sbtx(struct tb_port *port)
+{
+       int i;
+
+       for (i = TB_MAX_RETIMER_INDEX; i >= 1; i--)
+               usb4_port_retimer_unset_inbound_sbtx(port, i);
+}
+
 static ssize_t nvm_authenticate_store(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t count)
 {
@@ -234,6 +250,7 @@ static ssize_t nvm_authenticate_store(struct device *dev,
        rt->auth_status = 0;
 
        if (val) {
+               tb_retimer_set_inbound_sbtx(rt->port);
                if (val == AUTHENTICATE_ONLY) {
                        ret = tb_retimer_nvm_authenticate(rt, true);
                } else {
@@ -253,6 +270,7 @@ static ssize_t nvm_authenticate_store(struct device *dev,
        }
 
 exit_unlock:
+       tb_retimer_unset_inbound_sbtx(rt->port);
        mutex_unlock(&rt->tb->lock);
 exit_rpm:
        pm_runtime_mark_last_busy(&rt->dev);
@@ -466,8 +484,7 @@ int tb_retimer_scan(struct tb_port *port, bool add)
         * Enable sideband channel for each retimer. We can do this
         * regardless whether there is device connected or not.
         */
-       for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
-               usb4_port_retimer_set_inbound_sbtx(port, i);
+       tb_retimer_set_inbound_sbtx(port);
 
        /*
         * Before doing anything else, read the authentication status.
@@ -490,6 +507,8 @@ int tb_retimer_scan(struct tb_port *port, bool add)
                        break;
        }
 
+       tb_retimer_unset_inbound_sbtx(port);
+
        if (!last_idx)
                return 0;
 

diff --git a/drivers/thunderbolt/sb_regs.h b/drivers/thunderbolt/sb_regs.h
index bda889ff3bda5a2702b10ca9125c1ed6d1429145..a8a35b04035be2cee6096805fb97624cd476f89e 100644 (file)
--- a/drivers/thunderbolt/sb_regs.h
+++ b/drivers/thunderbolt/sb_regs.h
@@ -20,6 +20,7 @@ enum usb4_sb_opcode {
        USB4_SB_OPCODE_ROUTER_OFFLINE = 0x4e45534c,             /* "LSEN" */
        USB4_SB_OPCODE_ENUMERATE_RETIMERS = 0x4d554e45,         /* "ENUM" */
        USB4_SB_OPCODE_SET_INBOUND_SBTX = 0x5055534c,           /* "LSUP" */
+       USB4_SB_OPCODE_UNSET_INBOUND_SBTX = 0x50555355,         /* "USUP" */
        USB4_SB_OPCODE_QUERY_LAST_RETIMER = 0x5453414c,         /* "LAST" */
        USB4_SB_OPCODE_GET_NVM_SECTOR_SIZE = 0x53534e47,        /* "GNSS" */
        USB4_SB_OPCODE_NVM_SET_OFFSET = 0x53504f42,             /* "BOPS" */

diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 8922217d580c7c61a69c85e5bc598706daa01073..db0d3d37772fb05a18ad13a240fa66fecc1edc9b 100644 (file)
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -1080,6 +1080,7 @@ int usb4_port_router_online(struct tb_port *port);
 int usb4_port_enumerate_retimers(struct tb_port *port);
 
 int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index);
+int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index);
 int usb4_port_retimer_read(struct tb_port *port, u8 index, u8 reg, void *buf,
                           u8 size);
 int usb4_port_retimer_write(struct tb_port *port, u8 index, u8 reg,

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 8c61fe78f7fbafb441de6e6e42cff9c515f3951d..36547afa189669fb3c50079eccf1f27f18ea8771 100644 (file)
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1441,6 +1441,20 @@ int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index)
                                    500);
 }
 
+/**
+ * usb4_port_retimer_unset_inbound_sbtx() - Disable sideband channel transactions
+ * @port: USB4 port
+ * @index: Retimer index
+ *
+ * Disables sideband channel transations on SBTX. The reverse of
+ * usb4_port_retimer_set_inbound_sbtx().
+ */
+int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index)
+{
+       return usb4_port_retimer_op(port, index,
+                                   USB4_SB_OPCODE_UNSET_INBOUND_SBTX, 500);
+}
+
 /**
  * usb4_port_retimer_read() - Read from retimer sideband registers
  * @port: USB4 port