[PATCH v1 1/1] thunderbolt: Introduce usb4_port_sb_opcode_err_to_errno() helper

From: Andy Shevchenko
Date: Thu Mar 30 2023 - 06:27:50 EST


The usb4_port_sb_opcode_err_to_errno() converts from USB4 error codes
to the Linux errno space. In particular, this makes the intention
of the repeating usb4_port_retimer_read() call in the
usb4_port_retimer_nvm_authenticate_status() clearer.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/thunderbolt/usb4.c | 41 +++++++++++++++++++-------------------
1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 12355929e586..485b6e430686 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1303,6 +1303,20 @@ static int usb4_port_sb_write(struct tb_port *port, enum usb4_sb_target target,
return 0;
}

+static int usb4_port_sb_opcode_err_to_errno(u32 val)
+{
+ switch (val) {
+ case 0:
+ return 0;
+ case USB4_SB_OPCODE_ERR:
+ return -EAGAIN;
+ case USB4_SB_OPCODE_ONS:
+ return -EOPNOTSUPP;
+ default:
+ return -EIO;
+ }
+}
+
static int usb4_port_sb_op(struct tb_port *port, enum usb4_sb_target target,
u8 index, enum usb4_sb_opcode opcode, int timeout_msec)
{
@@ -1325,21 +1339,8 @@ static int usb4_port_sb_op(struct tb_port *port, enum usb4_sb_target target,
if (ret)
return ret;

- switch (val) {
- case 0:
- return 0;
-
- case USB4_SB_OPCODE_ERR:
- return -EAGAIN;
-
- case USB4_SB_OPCODE_ONS:
- return -EOPNOTSUPP;
-
- default:
- if (val != opcode)
- return -EIO;
- break;
- }
+ if (val != opcode)
+ return usb4_port_sb_opcode_err_to_errno(val);
} while (ktime_before(ktime_get(), timeout));

return -ETIMEDOUT;
@@ -1814,12 +1815,13 @@ int usb4_port_retimer_nvm_authenticate_status(struct tb_port *port, u8 index,
if (ret)
return ret;

- switch (val) {
+ ret = usb4_port_sb_opcode_err_to_errno(val);
+ switch (ret) {
case 0:
*status = 0;
return 0;

- case USB4_SB_OPCODE_ERR:
+ case -EAGAIN:
ret = usb4_port_retimer_read(port, index, USB4_SB_METADATA,
&metadata, sizeof(metadata));
if (ret)
@@ -1828,11 +1830,8 @@ int usb4_port_retimer_nvm_authenticate_status(struct tb_port *port, u8 index,
*status = metadata & USB4_SB_METADATA_NVM_AUTH_WRITE_MASK;
return 0;

- case USB4_SB_OPCODE_ONS:
- return -EOPNOTSUPP;
-
default:
- return -EIO;
+ return ret;
}
}

--
2.40.0.1.gaa8946217a0b