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authorMarc Kleine-Budde <mkl@pengutronix.de>2020-09-30 11:49:00 +0300
committerMarc Kleine-Budde <mkl@pengutronix.de>2020-09-30 22:54:30 +0300
commit1f0e21a0c0651ce3d837f8f76b44bf9de2b030cd (patch)
treeee32773a90f039233b68f3567f5c897a2ff79496 /drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c
parentdba1572c23601025b99e418066c82105eca950bc (diff)
downloadlinux-1f0e21a0c0651ce3d837f8f76b44bf9de2b030cd.tar.xz
can: mcp251xfd: rename driver files and subdir to mcp251xfd
In [1] Geert noted that the autodetect compatible for the mcp25xxfd driver, which is "microchip,mcp25xxfd" might be too generic and overlap with upcoming, but incompatible chips. In the previous patch the autodetect DT compatbile has been renamed to "microchip,mcp251xfd", this patch changes the name of the driver subdir and the individual files accordinly. [1] http://lore.kernel.org/r/CAMuHMdVkwGjr6dJuMyhQNqFoJqbh6Ec5V2b5LenCshwpM2SDsQ@mail.gmail.com Link: https://lore.kernel.org/r/20200930091424.792165-8-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c')
-rw-r--r--drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c
new file mode 100644
index 000000000000..bc90afb34df2
--- /dev/null
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-crc16.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// mcp25xxfd - Microchip MCP25xxFD Family CAN controller driver
+//
+// Copyright (c) 2020 Pengutronix,
+// Marc Kleine-Budde <kernel@pengutronix.de>
+//
+// Based on:
+//
+// CAN bus driver for Microchip 25XXFD CAN Controller with SPI Interface
+//
+// Copyright (c) 2019 Martin Sperl <kernel@martin.sperl.org>
+//
+
+#include "mcp251xfd.h"
+
+/* The standard crc16 in linux/crc16.h is unfortunately not computing
+ * the correct results (left shift vs. right shift). So here an
+ * implementation with a table generated with the help of:
+ *
+ * http://lkml.iu.edu/hypermail/linux/kernel/0508.1/1085.html
+ */
+static const u16 mcp25xxfd_crc16_table[] = {
+ 0x0000, 0x8005, 0x800f, 0x000a, 0x801b, 0x001e, 0x0014, 0x8011,
+ 0x8033, 0x0036, 0x003c, 0x8039, 0x0028, 0x802d, 0x8027, 0x0022,
+ 0x8063, 0x0066, 0x006c, 0x8069, 0x0078, 0x807d, 0x8077, 0x0072,
+ 0x0050, 0x8055, 0x805f, 0x005a, 0x804b, 0x004e, 0x0044, 0x8041,
+ 0x80c3, 0x00c6, 0x00cc, 0x80c9, 0x00d8, 0x80dd, 0x80d7, 0x00d2,
+ 0x00f0, 0x80f5, 0x80ff, 0x00fa, 0x80eb, 0x00ee, 0x00e4, 0x80e1,
+ 0x00a0, 0x80a5, 0x80af, 0x00aa, 0x80bb, 0x00be, 0x00b4, 0x80b1,
+ 0x8093, 0x0096, 0x009c, 0x8099, 0x0088, 0x808d, 0x8087, 0x0082,
+ 0x8183, 0x0186, 0x018c, 0x8189, 0x0198, 0x819d, 0x8197, 0x0192,
+ 0x01b0, 0x81b5, 0x81bf, 0x01ba, 0x81ab, 0x01ae, 0x01a4, 0x81a1,
+ 0x01e0, 0x81e5, 0x81ef, 0x01ea, 0x81fb, 0x01fe, 0x01f4, 0x81f1,
+ 0x81d3, 0x01d6, 0x01dc, 0x81d9, 0x01c8, 0x81cd, 0x81c7, 0x01c2,
+ 0x0140, 0x8145, 0x814f, 0x014a, 0x815b, 0x015e, 0x0154, 0x8151,
+ 0x8173, 0x0176, 0x017c, 0x8179, 0x0168, 0x816d, 0x8167, 0x0162,
+ 0x8123, 0x0126, 0x012c, 0x8129, 0x0138, 0x813d, 0x8137, 0x0132,
+ 0x0110, 0x8115, 0x811f, 0x011a, 0x810b, 0x010e, 0x0104, 0x8101,
+ 0x8303, 0x0306, 0x030c, 0x8309, 0x0318, 0x831d, 0x8317, 0x0312,
+ 0x0330, 0x8335, 0x833f, 0x033a, 0x832b, 0x032e, 0x0324, 0x8321,
+ 0x0360, 0x8365, 0x836f, 0x036a, 0x837b, 0x037e, 0x0374, 0x8371,
+ 0x8353, 0x0356, 0x035c, 0x8359, 0x0348, 0x834d, 0x8347, 0x0342,
+ 0x03c0, 0x83c5, 0x83cf, 0x03ca, 0x83db, 0x03de, 0x03d4, 0x83d1,
+ 0x83f3, 0x03f6, 0x03fc, 0x83f9, 0x03e8, 0x83ed, 0x83e7, 0x03e2,
+ 0x83a3, 0x03a6, 0x03ac, 0x83a9, 0x03b8, 0x83bd, 0x83b7, 0x03b2,
+ 0x0390, 0x8395, 0x839f, 0x039a, 0x838b, 0x038e, 0x0384, 0x8381,
+ 0x0280, 0x8285, 0x828f, 0x028a, 0x829b, 0x029e, 0x0294, 0x8291,
+ 0x82b3, 0x02b6, 0x02bc, 0x82b9, 0x02a8, 0x82ad, 0x82a7, 0x02a2,
+ 0x82e3, 0x02e6, 0x02ec, 0x82e9, 0x02f8, 0x82fd, 0x82f7, 0x02f2,
+ 0x02d0, 0x82d5, 0x82df, 0x02da, 0x82cb, 0x02ce, 0x02c4, 0x82c1,
+ 0x8243, 0x0246, 0x024c, 0x8249, 0x0258, 0x825d, 0x8257, 0x0252,
+ 0x0270, 0x8275, 0x827f, 0x027a, 0x826b, 0x026e, 0x0264, 0x8261,
+ 0x0220, 0x8225, 0x822f, 0x022a, 0x823b, 0x023e, 0x0234, 0x8231,
+ 0x8213, 0x0216, 0x021c, 0x8219, 0x0208, 0x820d, 0x8207, 0x0202
+};
+
+static inline u16 mcp25xxfd_crc16_byte(u16 crc, const u8 data)
+{
+ u8 index = (crc >> 8) ^ data;
+
+ return (crc << 8) ^ mcp25xxfd_crc16_table[index];
+}
+
+static u16 mcp25xxfd_crc16(u16 crc, u8 const *buffer, size_t len)
+{
+ while (len--)
+ crc = mcp25xxfd_crc16_byte(crc, *buffer++);
+
+ return crc;
+}
+
+u16 mcp25xxfd_crc16_compute(const void *data, size_t data_size)
+{
+ u16 crc = 0xffff;
+
+ return mcp25xxfd_crc16(crc, data, data_size);
+}
+
+u16 mcp25xxfd_crc16_compute2(const void *cmd, size_t cmd_size,
+ const void *data, size_t data_size)
+{
+ u16 crc;
+
+ crc = mcp25xxfd_crc16_compute(cmd, cmd_size);
+ crc = mcp25xxfd_crc16(crc, data, data_size);
+
+ return crc;
+}