thunderbolt: Make tb_switch_alloc() return ERR_PTR()
In order to detect possible connections to other domains we need to be
able to find out why tb_switch_alloc() fails so make it return ERR_PTR()
instead. This allows the caller to differentiate between errors such as
-ENOMEM which comes from the kernel and for instance -EIO which comes
from the hardware when trying to access the possible switch.
Convert all the current call sites to handle this properly.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index 805958e..d1f6ec89 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -468,7 +468,7 @@ static void add_switch(struct tb_switch *parent_sw, u64 route,
pm_runtime_get_sync(&parent_sw->dev);
sw = tb_switch_alloc(parent_sw->tb, &parent_sw->dev, route);
- if (!sw)
+ if (IS_ERR(sw))
goto out;
sw->uuid = kmemdup(uuid, sizeof(*uuid), GFP_KERNEL);
@@ -1848,8 +1848,8 @@ static int icm_start(struct tb *tb)
tb->root_switch = tb_switch_alloc_safe_mode(tb, &tb->dev, 0);
else
tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
- if (!tb->root_switch)
- return -ENODEV;
+ if (IS_ERR(tb->root_switch))
+ return PTR_ERR(tb->root_switch);
/*
* NVM upgrade has not been tested on Apple systems and they