thunderbolt: Properly disable path

We need to wait until all buffers have been drained before the path can
be considered disabled. Do this for every hop in a path.

This adds another bit field to struct tb_regs_hop even if we are trying
to get rid of them but we can clean them up another day.

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

diff --git a/drivers/thunderbolt/path.c b/drivers/thunderbolt/path.c
index a11956522bacdfa52da0a3dd00a4373b86196ec4..8c2e19a6117ad2aa00b2342d64582b02b23b6cb7 100644 (file)
--- a/drivers/thunderbolt/path.c
+++ b/drivers/thunderbolt/path.c
@@ -7,6 +7,8 @@
 
 #include <linux/slab.h>
 #include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/ktime.h>
 
 #include "tb.h"
 
@@ -74,14 +76,51 @@ static void __tb_path_deallocate_nfc(struct tb_path *path, int first_hop)
        }
 }
 
+static int __tb_path_deactivate_hop(struct tb_port *port, int hop_index)
+{
+       struct tb_regs_hop hop;
+       ktime_t timeout;
+       int ret;
+
+       /* Disable the path */
+       ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2);
+       if (ret)
+               return ret;
+
+       /* Already disabled */
+       if (!hop.enable)
+               return 0;
+
+       hop.enable = 0;
+
+       ret = tb_port_write(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2);
+       if (ret)
+               return ret;
+
+       /* Wait until it is drained */
+       timeout = ktime_add_ms(ktime_get(), 500);
+       do {
+               ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2);
+               if (ret)
+                       return ret;
+
+               if (!hop.pending)
+                       return 0;
+
+               usleep_range(10, 20);
+       } while (ktime_before(ktime_get(), timeout));
+
+       return -ETIMEDOUT;
+}
+
 static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop)
 {
        int i, res;
-       struct tb_regs_hop hop = { };
+
        for (i = first_hop; i < path->path_length; i++) {
-               res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS,
-                                   2 * path->hops[i].in_hop_index, 2);
-               if (res)
+               res = __tb_path_deactivate_hop(path->hops[i].in_port,
+                                              path->hops[i].in_hop_index);
+               if (res && res != -ENODEV)
                        tb_port_warn(path->hops[i].in_port,
                                     "hop deactivation failed for hop %d, index %d\n",
                                     i, path->hops[i].in_hop_index);

diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
index 1ab6e0fb31c0f8d18fe73460deecca6424fbcb11..82ac4ec8757f0071829d4331f6a8895a56fea7b9 100644 (file)
--- a/drivers/thunderbolt/tb_regs.h
+++ b/drivers/thunderbolt/tb_regs.h
@@ -234,7 +234,8 @@ struct tb_regs_hop {
        bool egress_fc:1;
        bool ingress_shared_buffer:1;
        bool egress_shared_buffer:1;
-       u32 unknown3:4; /* set to zero */
+       bool pending:1;
+       u32 unknown3:3; /* set to zero */
 } __packed;
 
 /* Common link controller registers */