This is a note to let you know that I've just added the patch titled
usb: typec: ucsi: Limit read size on v1.2
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-typec-ucsi-limit-read-size-on-v1.2.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 87e11f3db6757652c93aa7ba5eb4f8d7954e20ac
Author: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Date: Fri Feb 9 14:37:30 2024 -0800
usb: typec: ucsi: Limit read size on v1.2
[ Upstream commit b3db266fb031fba88c423d4bb8983a73a3db6527 ]
Between UCSI 1.2 and UCSI 2.0, the size of the MESSAGE_IN region was
increased from 16 to 256. In order to avoid overflowing reads for older
systems, add a mechanism to use the read UCSI version to truncate read
sizes on UCSI v1.2.
Tested-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
Reviewed-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240209143723.v5.1.Iacf5570a66b82b73ef03daa6557e2fc0db10266a@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 70d9f4eebf1a7..c4f5ee171cdeb 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -36,6 +36,19 @@
*/
#define UCSI_SWAP_TIMEOUT_MS 5000
+static int ucsi_read_message_in(struct ucsi *ucsi, void *buf,
+ size_t buf_size)
+{
+ /*
+ * Below UCSI 2.0, MESSAGE_IN was limited to 16 bytes. Truncate the
+ * reads here.
+ */
+ if (ucsi->version <= UCSI_VERSION_1_2)
+ buf_size = clamp(buf_size, 0, 16);
+
+ return ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, buf, buf_size);
+}
+
static int ucsi_acknowledge_command(struct ucsi *ucsi)
{
u64 ctrl;
@@ -72,7 +85,7 @@ static int ucsi_read_error(struct ucsi *ucsi)
if (ret < 0)
return ret;
- ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, &error, sizeof(error));
+ ret = ucsi_read_message_in(ucsi, &error, sizeof(error));
if (ret)
return ret;
@@ -174,7 +187,7 @@ int ucsi_send_command(struct ucsi *ucsi, u64 command,
length = ret;
if (data) {
- ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, data, size);
+ ret = ucsi_read_message_in(ucsi, data, size);
if (ret)
goto out;
}
@@ -1593,6 +1606,15 @@ int ucsi_register(struct ucsi *ucsi)
if (!ucsi->version)
return -ENODEV;
+ /*
+ * Version format is JJ.M.N (JJ = Major version, M = Minor version,
+ * N = sub-minor version).
+ */
+ dev_dbg(ucsi->dev, "Registered UCSI interface with version %x.%x.%x",
+ UCSI_BCD_GET_MAJOR(ucsi->version),
+ UCSI_BCD_GET_MINOR(ucsi->version),
+ UCSI_BCD_GET_SUBMINOR(ucsi->version));
+
queue_delayed_work(system_long_wq, &ucsi->work, 0);
ucsi_debugfs_register(ucsi);
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index 13ec976b1c747..2a886e58cd632 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -23,6 +23,17 @@ struct dentry;
#define UCSI_CONTROL 8
#define UCSI_MESSAGE_IN 16
#define UCSI_MESSAGE_OUT 32
+#define UCSIv2_MESSAGE_OUT 272
+
+/* UCSI versions */
+#define UCSI_VERSION_1_2 0x0120
+#define UCSI_VERSION_2_0 0x0200
+#define UCSI_VERSION_2_1 0x0210
+#define UCSI_VERSION_3_0 0x0300
+
+#define UCSI_BCD_GET_MAJOR(_v_) (((_v_) >> 8) & 0xFF)
+#define UCSI_BCD_GET_MINOR(_v_) (((_v_) >> 4) & 0x0F)
+#define UCSI_BCD_GET_SUBMINOR(_v_) ((_v_) & 0x0F)
/* Command Status and Connector Change Indication (CCI) bits */
#define UCSI_CCI_CONNECTOR(_c_) (((_c_) & GENMASK(7, 1)) >> 1)
