From mboxrd@z Thu Jan 1 00:00:00 1970 From: Quan Nguyen Date: Mon, 29 Mar 2021 19:17:57 +0700 Subject: [PATCH v1 1/3] i2c: i2c-core-smbus: Expose PEC calculate function for generic use In-Reply-To: <20210329121759.5644-1-quan@os.amperecomputing.com> References: <20210329121759.5644-1-quan@os.amperecomputing.com> Message-ID: <20210329121759.5644-2-quan@os.amperecomputing.com> List-Id: To: linux-aspeed@lists.ozlabs.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Expose the PEC calculation i2c_smbus_pec() for generic use. Signed-off-by: Quan Nguyen --- drivers/i2c/i2c-core-smbus.c | 12 ++++++++++-- include/linux/i2c.h | 1 + 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c index d2d32c0fd8c3..e5b2d1465e7e 100644 --- a/drivers/i2c/i2c-core-smbus.c +++ b/drivers/i2c/i2c-core-smbus.c @@ -37,8 +37,15 @@ static u8 crc8(u16 data) return (u8)(data >> 8); } -/* Incremental CRC8 over count bytes in the array pointed to by p */ -static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) +/** + * i2c_smbus_pec - Incremental CRC8 over the given input data array + * @crc: previous return crc8 value + * @p: pointer to data buffer. + * @count: number of bytes in data buffer. + * + * Incremental CRC8 over count bytes in the array pointed to by p + */ +u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) { int i; @@ -46,6 +53,7 @@ static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) crc = crc8((crc ^ p[i]) << 8); return crc; } +EXPORT_SYMBOL(i2c_smbus_pec); /* Assume a 7-bit address, which is reasonable for SMBus */ static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 56622658b215..0d75e5bcdde6 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -144,6 +144,7 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, /* Now follow the 'nice' access routines. These also document the calling conventions of i2c_smbus_xfer. */ +u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count); s32 i2c_smbus_read_byte(const struct i2c_client *client); s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command); -- 2.28.0