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authorMarc Kleine-Budde <mkl@pengutronix.de>2021-01-11 15:19:19 +0100
committerMarc Kleine-Budde <mkl@pengutronix.de>2021-01-13 09:42:59 +0100
commitbdd2e413192dd5f2153d166cd907b048cce872e8 (patch)
treecd3a0425d75cfa4d76d5fdf766eca8a9f89ac299 /drivers/net/can/dev/length.c
parent5a9d5ecd69ed65fc2d49cdecfc1c1ab1e4d7af34 (diff)
can: dev: move length related code into seperate file
This patch moves all CAN frame length related code of the CAN device infrastructure into a separate file. Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20210111141930.693847-5-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'drivers/net/can/dev/length.c')
-rw-r--r--drivers/net/can/dev/length.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/net/can/dev/length.c b/drivers/net/can/dev/length.c
new file mode 100644
index 000000000000..6fe18aa23ec9
--- /dev/null
+++ b/drivers/net/can/dev/length.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2012, 2020 Oliver Hartkopp <socketcan@hartkopp.net>
+ */
+
+#include <linux/can/dev.h>
+
+/* CAN DLC to real data length conversion helpers */
+
+static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 12, 16, 20, 24, 32, 48, 64};
+
+/* get data length from raw data length code (DLC) */
+u8 can_fd_dlc2len(u8 dlc)
+{
+ return dlc2len[dlc & 0x0F];
+}
+EXPORT_SYMBOL_GPL(can_fd_dlc2len);
+
+static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
+ 9, 9, 9, 9, /* 9 - 12 */
+ 10, 10, 10, 10, /* 13 - 16 */
+ 11, 11, 11, 11, /* 17 - 20 */
+ 12, 12, 12, 12, /* 21 - 24 */
+ 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
+ 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
+ 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
+ 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
+ 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */
+
+/* map the sanitized data length to an appropriate data length code */
+u8 can_fd_len2dlc(u8 len)
+{
+ if (unlikely(len > 64))
+ return 0xF;
+
+ return len2dlc[len];
+}
+EXPORT_SYMBOL_GPL(can_fd_len2dlc);