i2c: break out smbus support into separate file
authorWolfram Sang <wsa@the-dreams.de>
Tue, 23 May 2017 10:27:17 +0000 (12:27 +0200)
committerWolfram Sang <wsa@the-dreams.de>
Wed, 31 May 2017 19:01:03 +0000 (21:01 +0200)
Break out the exported SMBus functions and the emulation layer into a
separate file. This also involved splitting up the tracing header into
an I2C and an SMBus part.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Documentation/driver-api/i2c.rst
drivers/i2c/Makefile
drivers/i2c/i2c-core-base.c
drivers/i2c/i2c-core-smbus.c [new file with mode: 0644]
include/trace/events/i2c.h
include/trace/events/smbus.h [new file with mode: 0644]

index e6d4808..c215503 100644 (file)
@@ -44,3 +44,6 @@ i2c_adapter devices which don't support those I2C operations.
 
 .. kernel-doc:: drivers/i2c/i2c-core-base.c
    :export:
+
+.. kernel-doc:: drivers/i2c/i2c-core-smbus.c
+   :export:
index 6c54716..a6a90fe 100644 (file)
@@ -4,7 +4,7 @@
 
 obj-$(CONFIG_I2C_BOARDINFO)    += i2c-boardinfo.o
 obj-$(CONFIG_I2C)              += i2c-core.o
-i2c-core-objs                  := i2c-core-base.o
+i2c-core-objs                  := i2c-core-base.o i2c-core-smbus.o
 i2c-core-$(CONFIG_I2C_SLAVE)   += i2c-core-slave.o
 
 obj-$(CONFIG_I2C_SMBUS)                += i2c-smbus.o
index 88c0ca6..70fc462 100644 (file)
@@ -14,9 +14,6 @@
 /* ------------------------------------------------------------------------- */
 
 /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
-   All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
-   SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
-   Jean Delvare <jdelvare@suse.de>
    Mux support by Rodolfo Giometti <giometti@enneenne.com> and
    Michael Lawnick <michael.lawnick.ext@nsn.com>
    OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
@@ -3155,577 +3152,6 @@ void i2c_put_adapter(struct i2c_adapter *adap)
 }
 EXPORT_SYMBOL(i2c_put_adapter);
 
-/* The SMBus parts */
-
-#define POLY    (0x1070U << 3)
-static u8 crc8(u16 data)
-{
-       int i;
-
-       for (i = 0; i < 8; i++) {
-               if (data & 0x8000)
-                       data = data ^ POLY;
-               data = data << 1;
-       }
-       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)
-{
-       int i;
-
-       for (i = 0; i < count; i++)
-               crc = crc8((crc ^ p[i]) << 8);
-       return crc;
-}
-
-/* Assume a 7-bit address, which is reasonable for SMBus */
-static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg)
-{
-       /* The address will be sent first */
-       u8 addr = i2c_8bit_addr_from_msg(msg);
-       pec = i2c_smbus_pec(pec, &addr, 1);
-
-       /* The data buffer follows */
-       return i2c_smbus_pec(pec, msg->buf, msg->len);
-}
-
-/* Used for write only transactions */
-static inline void i2c_smbus_add_pec(struct i2c_msg *msg)
-{
-       msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg);
-       msg->len++;
-}
-
-/* Return <0 on CRC error
-   If there was a write before this read (most cases) we need to take the
-   partial CRC from the write part into account.
-   Note that this function does modify the message (we need to decrease the
-   message length to hide the CRC byte from the caller). */
-static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
-{
-       u8 rpec = msg->buf[--msg->len];
-       cpec = i2c_smbus_msg_pec(cpec, msg);
-
-       if (rpec != cpec) {
-               pr_debug("Bad PEC 0x%02x vs. 0x%02x\n",
-                       rpec, cpec);
-               return -EBADMSG;
-       }
-       return 0;
-}
-
-/**
- * i2c_smbus_read_byte - SMBus "receive byte" protocol
- * @client: Handle to slave device
- *
- * This executes the SMBus "receive byte" protocol, returning negative errno
- * else the byte received from the device.
- */
-s32 i2c_smbus_read_byte(const struct i2c_client *client)
-{
-       union i2c_smbus_data data;
-       int status;
-
-       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                               I2C_SMBUS_READ, 0,
-                               I2C_SMBUS_BYTE, &data);
-       return (status < 0) ? status : data.byte;
-}
-EXPORT_SYMBOL(i2c_smbus_read_byte);
-
-/**
- * i2c_smbus_write_byte - SMBus "send byte" protocol
- * @client: Handle to slave device
- * @value: Byte to be sent
- *
- * This executes the SMBus "send byte" protocol, returning negative errno
- * else zero on success.
- */
-s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value)
-{
-       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                             I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
-}
-EXPORT_SYMBOL(i2c_smbus_write_byte);
-
-/**
- * i2c_smbus_read_byte_data - SMBus "read byte" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- *
- * This executes the SMBus "read byte" protocol, returning negative errno
- * else a data byte received from the device.
- */
-s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command)
-{
-       union i2c_smbus_data data;
-       int status;
-
-       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                               I2C_SMBUS_READ, command,
-                               I2C_SMBUS_BYTE_DATA, &data);
-       return (status < 0) ? status : data.byte;
-}
-EXPORT_SYMBOL(i2c_smbus_read_byte_data);
-
-/**
- * i2c_smbus_write_byte_data - SMBus "write byte" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @value: Byte being written
- *
- * This executes the SMBus "write byte" protocol, returning negative errno
- * else zero on success.
- */
-s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command,
-                             u8 value)
-{
-       union i2c_smbus_data data;
-       data.byte = value;
-       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                             I2C_SMBUS_WRITE, command,
-                             I2C_SMBUS_BYTE_DATA, &data);
-}
-EXPORT_SYMBOL(i2c_smbus_write_byte_data);
-
-/**
- * i2c_smbus_read_word_data - SMBus "read word" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- *
- * This executes the SMBus "read word" protocol, returning negative errno
- * else a 16-bit unsigned "word" received from the device.
- */
-s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command)
-{
-       union i2c_smbus_data data;
-       int status;
-
-       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                               I2C_SMBUS_READ, command,
-                               I2C_SMBUS_WORD_DATA, &data);
-       return (status < 0) ? status : data.word;
-}
-EXPORT_SYMBOL(i2c_smbus_read_word_data);
-
-/**
- * i2c_smbus_write_word_data - SMBus "write word" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @value: 16-bit "word" being written
- *
- * This executes the SMBus "write word" protocol, returning negative errno
- * else zero on success.
- */
-s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command,
-                             u16 value)
-{
-       union i2c_smbus_data data;
-       data.word = value;
-       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                             I2C_SMBUS_WRITE, command,
-                             I2C_SMBUS_WORD_DATA, &data);
-}
-EXPORT_SYMBOL(i2c_smbus_write_word_data);
-
-/**
- * i2c_smbus_read_block_data - SMBus "block read" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @values: Byte array into which data will be read; big enough to hold
- *     the data returned by the slave.  SMBus allows at most 32 bytes.
- *
- * This executes the SMBus "block read" protocol, returning negative errno
- * else the number of data bytes in the slave's response.
- *
- * Note that using this function requires that the client's adapter support
- * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality.  Not all adapter drivers
- * support this; its emulation through I2C messaging relies on a specific
- * mechanism (I2C_M_RECV_LEN) which may not be implemented.
- */
-s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command,
-                             u8 *values)
-{
-       union i2c_smbus_data data;
-       int status;
-
-       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                               I2C_SMBUS_READ, command,
-                               I2C_SMBUS_BLOCK_DATA, &data);
-       if (status)
-               return status;
-
-       memcpy(values, &data.block[1], data.block[0]);
-       return data.block[0];
-}
-EXPORT_SYMBOL(i2c_smbus_read_block_data);
-
-/**
- * i2c_smbus_write_block_data - SMBus "block write" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @length: Size of data block; SMBus allows at most 32 bytes
- * @values: Byte array which will be written.
- *
- * This executes the SMBus "block write" protocol, returning negative errno
- * else zero on success.
- */
-s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command,
-                              u8 length, const u8 *values)
-{
-       union i2c_smbus_data data;
-
-       if (length > I2C_SMBUS_BLOCK_MAX)
-               length = I2C_SMBUS_BLOCK_MAX;
-       data.block[0] = length;
-       memcpy(&data.block[1], values, length);
-       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                             I2C_SMBUS_WRITE, command,
-                             I2C_SMBUS_BLOCK_DATA, &data);
-}
-EXPORT_SYMBOL(i2c_smbus_write_block_data);
-
-/* Returns the number of read bytes */
-s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command,
-                                 u8 length, u8 *values)
-{
-       union i2c_smbus_data data;
-       int status;
-
-       if (length > I2C_SMBUS_BLOCK_MAX)
-               length = I2C_SMBUS_BLOCK_MAX;
-       data.block[0] = length;
-       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                               I2C_SMBUS_READ, command,
-                               I2C_SMBUS_I2C_BLOCK_DATA, &data);
-       if (status < 0)
-               return status;
-
-       memcpy(values, &data.block[1], data.block[0]);
-       return data.block[0];
-}
-EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data);
-
-s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command,
-                                  u8 length, const u8 *values)
-{
-       union i2c_smbus_data data;
-
-       if (length > I2C_SMBUS_BLOCK_MAX)
-               length = I2C_SMBUS_BLOCK_MAX;
-       data.block[0] = length;
-       memcpy(data.block + 1, values, length);
-       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-                             I2C_SMBUS_WRITE, command,
-                             I2C_SMBUS_I2C_BLOCK_DATA, &data);
-}
-EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data);
-
-/* Simulate a SMBus command using the i2c protocol
-   No checking of parameters is done!  */
-static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
-                                  unsigned short flags,
-                                  char read_write, u8 command, int size,
-                                  union i2c_smbus_data *data)
-{
-       /* So we need to generate a series of msgs. In the case of writing, we
-         need to use only one message; when reading, we need two. We initialize
-         most things with sane defaults, to keep the code below somewhat
-         simpler. */
-       unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3];
-       unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2];
-       int num = read_write == I2C_SMBUS_READ ? 2 : 1;
-       int i;
-       u8 partial_pec = 0;
-       int status;
-       struct i2c_msg msg[2] = {
-               {
-                       .addr = addr,
-                       .flags = flags,
-                       .len = 1,
-                       .buf = msgbuf0,
-               }, {
-                       .addr = addr,
-                       .flags = flags | I2C_M_RD,
-                       .len = 0,
-                       .buf = msgbuf1,
-               },
-       };
-
-       msgbuf0[0] = command;
-       switch (size) {
-       case I2C_SMBUS_QUICK:
-               msg[0].len = 0;
-               /* Special case: The read/write field is used as data */
-               msg[0].flags = flags | (read_write == I2C_SMBUS_READ ?
-                                       I2C_M_RD : 0);
-               num = 1;
-               break;
-       case I2C_SMBUS_BYTE:
-               if (read_write == I2C_SMBUS_READ) {
-                       /* Special case: only a read! */
-                       msg[0].flags = I2C_M_RD | flags;
-                       num = 1;
-               }
-               break;
-       case I2C_SMBUS_BYTE_DATA:
-               if (read_write == I2C_SMBUS_READ)
-                       msg[1].len = 1;
-               else {
-                       msg[0].len = 2;
-                       msgbuf0[1] = data->byte;
-               }
-               break;
-       case I2C_SMBUS_WORD_DATA:
-               if (read_write == I2C_SMBUS_READ)
-                       msg[1].len = 2;
-               else {
-                       msg[0].len = 3;
-                       msgbuf0[1] = data->word & 0xff;
-                       msgbuf0[2] = data->word >> 8;
-               }
-               break;
-       case I2C_SMBUS_PROC_CALL:
-               num = 2; /* Special case */
-               read_write = I2C_SMBUS_READ;
-               msg[0].len = 3;
-               msg[1].len = 2;
-               msgbuf0[1] = data->word & 0xff;
-               msgbuf0[2] = data->word >> 8;
-               break;
-       case I2C_SMBUS_BLOCK_DATA:
-               if (read_write == I2C_SMBUS_READ) {
-                       msg[1].flags |= I2C_M_RECV_LEN;
-                       msg[1].len = 1; /* block length will be added by
-                                          the underlying bus driver */
-               } else {
-                       msg[0].len = data->block[0] + 2;
-                       if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) {
-                               dev_err(&adapter->dev,
-                                       "Invalid block write size %d\n",
-                                       data->block[0]);
-                               return -EINVAL;
-                       }
-                       for (i = 1; i < msg[0].len; i++)
-                               msgbuf0[i] = data->block[i-1];
-               }
-               break;
-       case I2C_SMBUS_BLOCK_PROC_CALL:
-               num = 2; /* Another special case */
-               read_write = I2C_SMBUS_READ;
-               if (data->block[0] > I2C_SMBUS_BLOCK_MAX) {
-                       dev_err(&adapter->dev,
-                               "Invalid block write size %d\n",
-                               data->block[0]);
-                       return -EINVAL;
-               }
-               msg[0].len = data->block[0] + 2;
-               for (i = 1; i < msg[0].len; i++)
-                       msgbuf0[i] = data->block[i-1];
-               msg[1].flags |= I2C_M_RECV_LEN;
-               msg[1].len = 1; /* block length will be added by
-                                  the underlying bus driver */
-               break;
-       case I2C_SMBUS_I2C_BLOCK_DATA:
-               if (read_write == I2C_SMBUS_READ) {
-                       msg[1].len = data->block[0];
-               } else {
-                       msg[0].len = data->block[0] + 1;
-                       if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) {
-                               dev_err(&adapter->dev,
-                                       "Invalid block write size %d\n",
-                                       data->block[0]);
-                               return -EINVAL;
-                       }
-                       for (i = 1; i <= data->block[0]; i++)
-                               msgbuf0[i] = data->block[i];
-               }
-               break;
-       default:
-               dev_err(&adapter->dev, "Unsupported transaction %d\n", size);
-               return -EOPNOTSUPP;
-       }
-
-       i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK
-                                     && size != I2C_SMBUS_I2C_BLOCK_DATA);
-       if (i) {
-               /* Compute PEC if first message is a write */
-               if (!(msg[0].flags & I2C_M_RD)) {
-                       if (num == 1) /* Write only */
-                               i2c_smbus_add_pec(&msg[0]);
-                       else /* Write followed by read */
-                               partial_pec = i2c_smbus_msg_pec(0, &msg[0]);
-               }
-               /* Ask for PEC if last message is a read */
-               if (msg[num-1].flags & I2C_M_RD)
-                       msg[num-1].len++;
-       }
-
-       status = i2c_transfer(adapter, msg, num);
-       if (status < 0)
-               return status;
-
-       /* Check PEC if last message is a read */
-       if (i && (msg[num-1].flags & I2C_M_RD)) {
-               status = i2c_smbus_check_pec(partial_pec, &msg[num-1]);
-               if (status < 0)
-                       return status;
-       }
-
-       if (read_write == I2C_SMBUS_READ)
-               switch (size) {
-               case I2C_SMBUS_BYTE:
-                       data->byte = msgbuf0[0];
-                       break;
-               case I2C_SMBUS_BYTE_DATA:
-                       data->byte = msgbuf1[0];
-                       break;
-               case I2C_SMBUS_WORD_DATA:
-               case I2C_SMBUS_PROC_CALL:
-                       data->word = msgbuf1[0] | (msgbuf1[1] << 8);
-                       break;
-               case I2C_SMBUS_I2C_BLOCK_DATA:
-                       for (i = 0; i < data->block[0]; i++)
-                               data->block[i+1] = msgbuf1[i];
-                       break;
-               case I2C_SMBUS_BLOCK_DATA:
-               case I2C_SMBUS_BLOCK_PROC_CALL:
-                       for (i = 0; i < msgbuf1[0] + 1; i++)
-                               data->block[i] = msgbuf1[i];
-                       break;
-               }
-       return 0;
-}
-
-/**
- * i2c_smbus_xfer - execute SMBus protocol operations
- * @adapter: Handle to I2C bus
- * @addr: Address of SMBus slave on that bus
- * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC)
- * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE
- * @command: Byte interpreted by slave, for protocols which use such bytes
- * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL
- * @data: Data to be read or written
- *
- * This executes an SMBus protocol operation, and returns a negative
- * errno code else zero on success.
- */
-s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
-                  char read_write, u8 command, int protocol,
-                  union i2c_smbus_data *data)
-{
-       unsigned long orig_jiffies;
-       int try;
-       s32 res;
-
-       /* If enabled, the following two tracepoints are conditional on
-        * read_write and protocol.
-        */
-       trace_smbus_write(adapter, addr, flags, read_write,
-                         command, protocol, data);
-       trace_smbus_read(adapter, addr, flags, read_write,
-                        command, protocol);
-
-       flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB;
-
-       if (adapter->algo->smbus_xfer) {
-               i2c_lock_bus(adapter, I2C_LOCK_SEGMENT);
-
-               /* Retry automatically on arbitration loss */
-               orig_jiffies = jiffies;
-               for (res = 0, try = 0; try <= adapter->retries; try++) {
-                       res = adapter->algo->smbus_xfer(adapter, addr, flags,
-                                                       read_write, command,
-                                                       protocol, data);
-                       if (res != -EAGAIN)
-                               break;
-                       if (time_after(jiffies,
-                                      orig_jiffies + adapter->timeout))
-                               break;
-               }
-               i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
-
-               if (res != -EOPNOTSUPP || !adapter->algo->master_xfer)
-                       goto trace;
-               /*
-                * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't
-                * implement native support for the SMBus operation.
-                */
-       }
-
-       res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
-                                     command, protocol, data);
-
-trace:
-       /* If enabled, the reply tracepoint is conditional on read_write. */
-       trace_smbus_reply(adapter, addr, flags, read_write,
-                         command, protocol, data);
-       trace_smbus_result(adapter, addr, flags, read_write,
-                          command, protocol, res);
-
-       return res;
-}
-EXPORT_SYMBOL(i2c_smbus_xfer);
-
-/**
- * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes
- * @values: Byte array into which data will be read; big enough to hold
- *     the data returned by the slave.  SMBus allows at most
- *     I2C_SMBUS_BLOCK_MAX bytes.
- *
- * This executes the SMBus "block read" protocol if supported by the adapter.
- * If block read is not supported, it emulates it using either word or byte
- * read protocols depending on availability.
- *
- * The addresses of the I2C slave device that are accessed with this function
- * must be mapped to a linear region, so that a block read will have the same
- * effect as a byte read. Before using this function you must double-check
- * if the I2C slave does support exchanging a block transfer with a byte
- * transfer.
- */
-s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
-                                             u8 command, u8 length, u8 *values)
-{
-       u8 i = 0;
-       int status;
-
-       if (length > I2C_SMBUS_BLOCK_MAX)
-               length = I2C_SMBUS_BLOCK_MAX;
-
-       if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK))
-               return i2c_smbus_read_i2c_block_data(client, command, length, values);
-
-       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA))
-               return -EOPNOTSUPP;
-
-       if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) {
-               while ((i + 2) <= length) {
-                       status = i2c_smbus_read_word_data(client, command + i);
-                       if (status < 0)
-                               return status;
-                       values[i] = status & 0xff;
-                       values[i + 1] = status >> 8;
-                       i += 2;
-               }
-       }
-
-       while (i < length) {
-               status = i2c_smbus_read_byte_data(client, command + i);
-               if (status < 0)
-                       return status;
-               values[i] = status;
-               i++;
-       }
-
-       return i;
-}
-EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated);
-
 MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
 MODULE_DESCRIPTION("I2C-Bus main module");
 MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
new file mode 100644 (file)
index 0000000..10f00a8
--- /dev/null
@@ -0,0 +1,594 @@
+/*
+ * Linux I2C core SMBus and SMBus emulation code
+ *
+ * This file contains the SMBus functions which are always included in the I2C
+ * core because they can be emulated via I2C. SMBus specific extensions
+ * (e.g. smbalert) are handled in a seperate i2c-smbus module.
+ *
+ * All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
+ * SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
+ * Jean Delvare <jdelvare@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/smbus.h>
+
+
+/* The SMBus parts */
+
+#define POLY    (0x1070U << 3)
+static u8 crc8(u16 data)
+{
+       int i;
+
+       for (i = 0; i < 8; i++) {
+               if (data & 0x8000)
+                       data = data ^ POLY;
+               data = data << 1;
+       }
+       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)
+{
+       int i;
+
+       for (i = 0; i < count; i++)
+               crc = crc8((crc ^ p[i]) << 8);
+       return crc;
+}
+
+/* Assume a 7-bit address, which is reasonable for SMBus */
+static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg)
+{
+       /* The address will be sent first */
+       u8 addr = i2c_8bit_addr_from_msg(msg);
+       pec = i2c_smbus_pec(pec, &addr, 1);
+
+       /* The data buffer follows */
+       return i2c_smbus_pec(pec, msg->buf, msg->len);
+}
+
+/* Used for write only transactions */
+static inline void i2c_smbus_add_pec(struct i2c_msg *msg)
+{
+       msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg);
+       msg->len++;
+}
+
+/* Return <0 on CRC error
+   If there was a write before this read (most cases) we need to take the
+   partial CRC from the write part into account.
+   Note that this function does modify the message (we need to decrease the
+   message length to hide the CRC byte from the caller). */
+static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
+{
+       u8 rpec = msg->buf[--msg->len];
+       cpec = i2c_smbus_msg_pec(cpec, msg);
+
+       if (rpec != cpec) {
+               pr_debug("Bad PEC 0x%02x vs. 0x%02x\n",
+                       rpec, cpec);
+               return -EBADMSG;
+       }
+       return 0;
+}
+
+/**
+ * i2c_smbus_read_byte - SMBus "receive byte" protocol
+ * @client: Handle to slave device
+ *
+ * This executes the SMBus "receive byte" protocol, returning negative errno
+ * else the byte received from the device.
+ */
+s32 i2c_smbus_read_byte(const struct i2c_client *client)
+{
+       union i2c_smbus_data data;
+       int status;
+
+       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                               I2C_SMBUS_READ, 0,
+                               I2C_SMBUS_BYTE, &data);
+       return (status < 0) ? status : data.byte;
+}
+EXPORT_SYMBOL(i2c_smbus_read_byte);
+
+/**
+ * i2c_smbus_write_byte - SMBus "send byte" protocol
+ * @client: Handle to slave device
+ * @value: Byte to be sent
+ *
+ * This executes the SMBus "send byte" protocol, returning negative errno
+ * else zero on success.
+ */
+s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value)
+{
+       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                             I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
+}
+EXPORT_SYMBOL(i2c_smbus_write_byte);
+
+/**
+ * i2c_smbus_read_byte_data - SMBus "read byte" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ *
+ * This executes the SMBus "read byte" protocol, returning negative errno
+ * else a data byte received from the device.
+ */
+s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command)
+{
+       union i2c_smbus_data data;
+       int status;
+
+       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                               I2C_SMBUS_READ, command,
+                               I2C_SMBUS_BYTE_DATA, &data);
+       return (status < 0) ? status : data.byte;
+}
+EXPORT_SYMBOL(i2c_smbus_read_byte_data);
+
+/**
+ * i2c_smbus_write_byte_data - SMBus "write byte" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @value: Byte being written
+ *
+ * This executes the SMBus "write byte" protocol, returning negative errno
+ * else zero on success.
+ */
+s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command,
+                             u8 value)
+{
+       union i2c_smbus_data data;
+       data.byte = value;
+       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                             I2C_SMBUS_WRITE, command,
+                             I2C_SMBUS_BYTE_DATA, &data);
+}
+EXPORT_SYMBOL(i2c_smbus_write_byte_data);
+
+/**
+ * i2c_smbus_read_word_data - SMBus "read word" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ *
+ * This executes the SMBus "read word" protocol, returning negative errno
+ * else a 16-bit unsigned "word" received from the device.
+ */
+s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command)
+{
+       union i2c_smbus_data data;
+       int status;
+
+       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                               I2C_SMBUS_READ, command,
+                               I2C_SMBUS_WORD_DATA, &data);
+       return (status < 0) ? status : data.word;
+}
+EXPORT_SYMBOL(i2c_smbus_read_word_data);
+
+/**
+ * i2c_smbus_write_word_data - SMBus "write word" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @value: 16-bit "word" being written
+ *
+ * This executes the SMBus "write word" protocol, returning negative errno
+ * else zero on success.
+ */
+s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command,
+                             u16 value)
+{
+       union i2c_smbus_data data;
+       data.word = value;
+       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                             I2C_SMBUS_WRITE, command,
+                             I2C_SMBUS_WORD_DATA, &data);
+}
+EXPORT_SYMBOL(i2c_smbus_write_word_data);
+
+/**
+ * i2c_smbus_read_block_data - SMBus "block read" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @values: Byte array into which data will be read; big enough to hold
+ *     the data returned by the slave.  SMBus allows at most 32 bytes.
+ *
+ * This executes the SMBus "block read" protocol, returning negative errno
+ * else the number of data bytes in the slave's response.
+ *
+ * Note that using this function requires that the client's adapter support
+ * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality.  Not all adapter drivers
+ * support this; its emulation through I2C messaging relies on a specific
+ * mechanism (I2C_M_RECV_LEN) which may not be implemented.
+ */
+s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command,
+                             u8 *values)
+{
+       union i2c_smbus_data data;
+       int status;
+
+       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                               I2C_SMBUS_READ, command,
+                               I2C_SMBUS_BLOCK_DATA, &data);
+       if (status)
+               return status;
+
+       memcpy(values, &data.block[1], data.block[0]);
+       return data.block[0];
+}
+EXPORT_SYMBOL(i2c_smbus_read_block_data);
+
+/**
+ * i2c_smbus_write_block_data - SMBus "block write" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @length: Size of data block; SMBus allows at most 32 bytes
+ * @values: Byte array which will be written.
+ *
+ * This executes the SMBus "block write" protocol, returning negative errno
+ * else zero on success.
+ */
+s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command,
+                              u8 length, const u8 *values)
+{
+       union i2c_smbus_data data;
+
+       if (length > I2C_SMBUS_BLOCK_MAX)
+               length = I2C_SMBUS_BLOCK_MAX;
+       data.block[0] = length;
+       memcpy(&data.block[1], values, length);
+       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                             I2C_SMBUS_WRITE, command,
+                             I2C_SMBUS_BLOCK_DATA, &data);
+}
+EXPORT_SYMBOL(i2c_smbus_write_block_data);
+
+/* Returns the number of read bytes */
+s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command,
+                                 u8 length, u8 *values)
+{
+       union i2c_smbus_data data;
+       int status;
+
+       if (length > I2C_SMBUS_BLOCK_MAX)
+               length = I2C_SMBUS_BLOCK_MAX;
+       data.block[0] = length;
+       status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                               I2C_SMBUS_READ, command,
+                               I2C_SMBUS_I2C_BLOCK_DATA, &data);
+       if (status < 0)
+               return status;
+
+       memcpy(values, &data.block[1], data.block[0]);
+       return data.block[0];
+}
+EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data);
+
+s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command,
+                                  u8 length, const u8 *values)
+{
+       union i2c_smbus_data data;
+
+       if (length > I2C_SMBUS_BLOCK_MAX)
+               length = I2C_SMBUS_BLOCK_MAX;
+       data.block[0] = length;
+       memcpy(data.block + 1, values, length);
+       return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+                             I2C_SMBUS_WRITE, command,
+                             I2C_SMBUS_I2C_BLOCK_DATA, &data);
+}
+EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data);
+
+/* Simulate a SMBus command using the i2c protocol
+   No checking of parameters is done!  */
+static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
+                                  unsigned short flags,
+                                  char read_write, u8 command, int size,
+                                  union i2c_smbus_data *data)
+{
+       /* So we need to generate a series of msgs. In the case of writing, we
+         need to use only one message; when reading, we need two. We initialize
+         most things with sane defaults, to keep the code below somewhat
+         simpler. */
+       unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3];
+       unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2];
+       int num = read_write == I2C_SMBUS_READ ? 2 : 1;
+       int i;
+       u8 partial_pec = 0;
+       int status;
+       struct i2c_msg msg[2] = {
+               {
+                       .addr = addr,
+                       .flags = flags,
+                       .len = 1,
+                       .buf = msgbuf0,
+               }, {
+                       .addr = addr,
+                       .flags = flags | I2C_M_RD,
+                       .len = 0,
+                       .buf = msgbuf1,
+               },
+       };
+
+       msgbuf0[0] = command;
+       switch (size) {
+       case I2C_SMBUS_QUICK:
+               msg[0].len = 0;
+               /* Special case: The read/write field is used as data */
+               msg[0].flags = flags | (read_write == I2C_SMBUS_READ ?
+                                       I2C_M_RD : 0);
+               num = 1;
+               break;
+       case I2C_SMBUS_BYTE:
+               if (read_write == I2C_SMBUS_READ) {
+                       /* Special case: only a read! */
+                       msg[0].flags = I2C_M_RD | flags;
+                       num = 1;
+               }
+               break;
+       case I2C_SMBUS_BYTE_DATA:
+               if (read_write == I2C_SMBUS_READ)
+                       msg[1].len = 1;
+               else {
+                       msg[0].len = 2;
+                       msgbuf0[1] = data->byte;
+               }
+               break;
+       case I2C_SMBUS_WORD_DATA:
+               if (read_write == I2C_SMBUS_READ)
+                       msg[1].len = 2;
+               else {
+                       msg[0].len = 3;
+                       msgbuf0[1] = data->word & 0xff;
+                       msgbuf0[2] = data->word >> 8;
+               }
+               break;
+       case I2C_SMBUS_PROC_CALL:
+               num = 2; /* Special case */
+               read_write = I2C_SMBUS_READ;
+               msg[0].len = 3;
+               msg[1].len = 2;
+               msgbuf0[1] = data->word & 0xff;
+               msgbuf0[2] = data->word >> 8;
+               break;
+       case I2C_SMBUS_BLOCK_DATA:
+               if (read_write == I2C_SMBUS_READ) {
+                       msg[1].flags |= I2C_M_RECV_LEN;
+                       msg[1].len = 1; /* block length will be added by
+                                          the underlying bus driver */
+               } else {
+                       msg[0].len = data->block[0] + 2;
+                       if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) {
+                               dev_err(&adapter->dev,
+                                       "Invalid block write size %d\n",
+                                       data->block[0]);
+                               return -EINVAL;
+                       }
+                       for (i = 1; i < msg[0].len; i++)
+                               msgbuf0[i] = data->block[i-1];
+               }
+               break;
+       case I2C_SMBUS_BLOCK_PROC_CALL:
+               num = 2; /* Another special case */
+               read_write = I2C_SMBUS_READ;
+               if (data->block[0] > I2C_SMBUS_BLOCK_MAX) {
+                       dev_err(&adapter->dev,
+                               "Invalid block write size %d\n",
+                               data->block[0]);
+                       return -EINVAL;
+               }
+               msg[0].len = data->block[0] + 2;
+               for (i = 1; i < msg[0].len; i++)
+                       msgbuf0[i] = data->block[i-1];
+               msg[1].flags |= I2C_M_RECV_LEN;
+               msg[1].len = 1; /* block length will be added by
+                                  the underlying bus driver */
+               break;
+       case I2C_SMBUS_I2C_BLOCK_DATA:
+               if (read_write == I2C_SMBUS_READ) {
+                       msg[1].len = data->block[0];
+               } else {
+                       msg[0].len = data->block[0] + 1;
+                       if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) {
+                               dev_err(&adapter->dev,
+                                       "Invalid block write size %d\n",
+                                       data->block[0]);
+                               return -EINVAL;
+                       }
+                       for (i = 1; i <= data->block[0]; i++)
+                               msgbuf0[i] = data->block[i];
+               }
+               break;
+       default:
+               dev_err(&adapter->dev, "Unsupported transaction %d\n", size);
+               return -EOPNOTSUPP;
+       }
+
+       i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK
+                                     && size != I2C_SMBUS_I2C_BLOCK_DATA);
+       if (i) {
+               /* Compute PEC if first message is a write */
+               if (!(msg[0].flags & I2C_M_RD)) {
+                       if (num == 1) /* Write only */
+                               i2c_smbus_add_pec(&msg[0]);
+                       else /* Write followed by read */
+                               partial_pec = i2c_smbus_msg_pec(0, &msg[0]);
+               }
+               /* Ask for PEC if last message is a read */
+               if (msg[num-1].flags & I2C_M_RD)
+                       msg[num-1].len++;
+       }
+
+       status = i2c_transfer(adapter, msg, num);
+       if (status < 0)
+               return status;
+
+       /* Check PEC if last message is a read */
+       if (i && (msg[num-1].flags & I2C_M_RD)) {
+               status = i2c_smbus_check_pec(partial_pec, &msg[num-1]);
+               if (status < 0)
+                       return status;
+       }
+
+       if (read_write == I2C_SMBUS_READ)
+               switch (size) {
+               case I2C_SMBUS_BYTE:
+                       data->byte = msgbuf0[0];
+                       break;
+               case I2C_SMBUS_BYTE_DATA:
+                       data->byte = msgbuf1[0];
+                       break;
+               case I2C_SMBUS_WORD_DATA:
+               case I2C_SMBUS_PROC_CALL:
+                       data->word = msgbuf1[0] | (msgbuf1[1] << 8);
+                       break;
+               case I2C_SMBUS_I2C_BLOCK_DATA:
+                       for (i = 0; i < data->block[0]; i++)
+                               data->block[i+1] = msgbuf1[i];
+                       break;
+               case I2C_SMBUS_BLOCK_DATA:
+               case I2C_SMBUS_BLOCK_PROC_CALL:
+                       for (i = 0; i < msgbuf1[0] + 1; i++)
+                               data->block[i] = msgbuf1[i];
+                       break;
+               }
+       return 0;
+}
+
+/**
+ * i2c_smbus_xfer - execute SMBus protocol operations
+ * @adapter: Handle to I2C bus
+ * @addr: Address of SMBus slave on that bus
+ * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC)
+ * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE
+ * @command: Byte interpreted by slave, for protocols which use such bytes
+ * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL
+ * @data: Data to be read or written
+ *
+ * This executes an SMBus protocol operation, and returns a negative
+ * errno code else zero on success.
+ */
+s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
+                  char read_write, u8 command, int protocol,
+                  union i2c_smbus_data *data)
+{
+       unsigned long orig_jiffies;
+       int try;
+       s32 res;
+
+       /* If enabled, the following two tracepoints are conditional on
+        * read_write and protocol.
+        */
+       trace_smbus_write(adapter, addr, flags, read_write,
+                         command, protocol, data);
+       trace_smbus_read(adapter, addr, flags, read_write,
+                        command, protocol);
+
+       flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB;
+
+       if (adapter->algo->smbus_xfer) {
+               i2c_lock_bus(adapter, I2C_LOCK_SEGMENT);
+
+               /* Retry automatically on arbitration loss */
+               orig_jiffies = jiffies;
+               for (res = 0, try = 0; try <= adapter->retries; try++) {
+                       res = adapter->algo->smbus_xfer(adapter, addr, flags,
+                                                       read_write, command,
+                                                       protocol, data);
+                       if (res != -EAGAIN)
+                               break;
+                       if (time_after(jiffies,
+                                      orig_jiffies + adapter->timeout))
+                               break;
+               }
+               i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
+
+               if (res != -EOPNOTSUPP || !adapter->algo->master_xfer)
+                       goto trace;
+               /*
+                * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't
+                * implement native support for the SMBus operation.
+                */
+       }
+
+       res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
+                                     command, protocol, data);
+
+trace:
+       /* If enabled, the reply tracepoint is conditional on read_write. */
+       trace_smbus_reply(adapter, addr, flags, read_write,
+                         command, protocol, data);
+       trace_smbus_result(adapter, addr, flags, read_write,
+                          command, protocol, res);
+
+       return res;
+}
+EXPORT_SYMBOL(i2c_smbus_xfer);
+
+/**
+ * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes
+ * @values: Byte array into which data will be read; big enough to hold
+ *     the data returned by the slave.  SMBus allows at most
+ *     I2C_SMBUS_BLOCK_MAX bytes.
+ *
+ * This executes the SMBus "block read" protocol if supported by the adapter.
+ * If block read is not supported, it emulates it using either word or byte
+ * read protocols depending on availability.
+ *
+ * The addresses of the I2C slave device that are accessed with this function
+ * must be mapped to a linear region, so that a block read will have the same
+ * effect as a byte read. Before using this function you must double-check
+ * if the I2C slave does support exchanging a block transfer with a byte
+ * transfer.
+ */
+s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
+                                             u8 command, u8 length, u8 *values)
+{
+       u8 i = 0;
+       int status;
+
+       if (length > I2C_SMBUS_BLOCK_MAX)
+               length = I2C_SMBUS_BLOCK_MAX;
+
+       if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+               return i2c_smbus_read_i2c_block_data(client, command, length, values);
+
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA))
+               return -EOPNOTSUPP;
+
+       if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) {
+               while ((i + 2) <= length) {
+                       status = i2c_smbus_read_word_data(client, command + i);
+                       if (status < 0)
+                               return status;
+                       values[i] = status & 0xff;
+                       values[i + 1] = status >> 8;
+                       i += 2;
+               }
+       }
+
+       while (i < length) {
+               status = i2c_smbus_read_byte_data(client, command + i);
+               if (status < 0)
+                       return status;
+               values[i] = status;
+               i++;
+       }
+
+       return i;
+}
+EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated);
index 4abb8ea..86a4011 100644 (file)
@@ -1,4 +1,4 @@
-/* I2C and SMBUS message transfer tracepoints
+/* I2C message transfer tracepoints
  *
  * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
@@ -18,7 +18,7 @@
 #include <linux/tracepoint.h>
 
 /*
- * drivers/i2c/i2c-core.c
+ * drivers/i2c/i2c-core-base.c
  */
 extern int i2c_transfer_trace_reg(void);
 extern void i2c_transfer_trace_unreg(void);
@@ -144,228 +144,6 @@ TRACE_EVENT_FN(i2c_result,
               i2c_transfer_trace_reg,
               i2c_transfer_trace_unreg);
 
-/*
- * i2c_smbus_xfer() write data or procedure call request
- */
-TRACE_EVENT_CONDITION(smbus_write,
-       TP_PROTO(const struct i2c_adapter *adap,
-                u16 addr, unsigned short flags,
-                char read_write, u8 command, int protocol,
-                const union i2c_smbus_data *data),
-       TP_ARGS(adap, addr, flags, read_write, command, protocol, data),
-       TP_CONDITION(read_write == I2C_SMBUS_WRITE ||
-                    protocol == I2C_SMBUS_PROC_CALL ||
-                    protocol == I2C_SMBUS_BLOCK_PROC_CALL),
-       TP_STRUCT__entry(
-               __field(int,    adapter_nr              )
-               __field(__u16,  addr                    )
-               __field(__u16,  flags                   )
-               __field(__u8,   command                 )
-               __field(__u8,   len                     )
-               __field(__u32,  protocol                )
-               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
-       TP_fast_assign(
-               __entry->adapter_nr = adap->nr;
-               __entry->addr = addr;
-               __entry->flags = flags;
-               __entry->command = command;
-               __entry->protocol = protocol;
-
-               switch (protocol) {
-               case I2C_SMBUS_BYTE_DATA:
-                       __entry->len = 1;
-                       goto copy;
-               case I2C_SMBUS_WORD_DATA:
-               case I2C_SMBUS_PROC_CALL:
-                       __entry->len = 2;
-                       goto copy;
-               case I2C_SMBUS_BLOCK_DATA:
-               case I2C_SMBUS_BLOCK_PROC_CALL:
-               case I2C_SMBUS_I2C_BLOCK_DATA:
-                       __entry->len = data->block[0] + 1;
-               copy:
-                       memcpy(__entry->buf, data->block, __entry->len);
-                       break;
-               case I2C_SMBUS_QUICK:
-               case I2C_SMBUS_BYTE:
-               case I2C_SMBUS_I2C_BLOCK_BROKEN:
-               default:
-                       __entry->len = 0;
-               }
-                      ),
-       TP_printk("i2c-%d a=%03x f=%04x c=%x %s l=%u [%*phD]",
-                 __entry->adapter_nr,
-                 __entry->addr,
-                 __entry->flags,
-                 __entry->command,
-                 __print_symbolic(__entry->protocol,
-                                  { I2C_SMBUS_QUICK,           "QUICK" },
-                                  { I2C_SMBUS_BYTE,            "BYTE"  },
-                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
-                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
-                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
-                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
-                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
-                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
-                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" }),
-                 __entry->len,
-                 __entry->len, __entry->buf
-                 ));
-
-/*
- * i2c_smbus_xfer() read data request
- */
-TRACE_EVENT_CONDITION(smbus_read,
-       TP_PROTO(const struct i2c_adapter *adap,
-                u16 addr, unsigned short flags,
-                char read_write, u8 command, int protocol),
-       TP_ARGS(adap, addr, flags, read_write, command, protocol),
-       TP_CONDITION(!(read_write == I2C_SMBUS_WRITE ||
-                      protocol == I2C_SMBUS_PROC_CALL ||
-                      protocol == I2C_SMBUS_BLOCK_PROC_CALL)),
-       TP_STRUCT__entry(
-               __field(int,    adapter_nr              )
-               __field(__u16,  flags                   )
-               __field(__u16,  addr                    )
-               __field(__u8,   command                 )
-               __field(__u32,  protocol                )
-               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
-       TP_fast_assign(
-               __entry->adapter_nr = adap->nr;
-               __entry->addr = addr;
-               __entry->flags = flags;
-               __entry->command = command;
-               __entry->protocol = protocol;
-                      ),
-       TP_printk("i2c-%d a=%03x f=%04x c=%x %s",
-                 __entry->adapter_nr,
-                 __entry->addr,
-                 __entry->flags,
-                 __entry->command,
-                 __print_symbolic(__entry->protocol,
-                                  { I2C_SMBUS_QUICK,           "QUICK" },
-                                  { I2C_SMBUS_BYTE,            "BYTE"  },
-                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
-                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
-                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
-                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
-                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
-                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
-                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" })
-                 ));
-
-/*
- * i2c_smbus_xfer() read data or procedure call reply
- */
-TRACE_EVENT_CONDITION(smbus_reply,
-       TP_PROTO(const struct i2c_adapter *adap,
-                u16 addr, unsigned short flags,
-                char read_write, u8 command, int protocol,
-                const union i2c_smbus_data *data),
-       TP_ARGS(adap, addr, flags, read_write, command, protocol, data),
-       TP_CONDITION(read_write == I2C_SMBUS_READ),
-       TP_STRUCT__entry(
-               __field(int,    adapter_nr              )
-               __field(__u16,  addr                    )
-               __field(__u16,  flags                   )
-               __field(__u8,   command                 )
-               __field(__u8,   len                     )
-               __field(__u32,  protocol                )
-               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
-       TP_fast_assign(
-               __entry->adapter_nr = adap->nr;
-               __entry->addr = addr;
-               __entry->flags = flags;
-               __entry->command = command;
-               __entry->protocol = protocol;
-
-               switch (protocol) {
-               case I2C_SMBUS_BYTE:
-               case I2C_SMBUS_BYTE_DATA:
-                       __entry->len = 1;
-                       goto copy;
-               case I2C_SMBUS_WORD_DATA:
-               case I2C_SMBUS_PROC_CALL:
-                       __entry->len = 2;
-                       goto copy;
-               case I2C_SMBUS_BLOCK_DATA:
-               case I2C_SMBUS_BLOCK_PROC_CALL:
-               case I2C_SMBUS_I2C_BLOCK_DATA:
-                       __entry->len = data->block[0] + 1;
-               copy:
-                       memcpy(__entry->buf, data->block, __entry->len);
-                       break;
-               case I2C_SMBUS_QUICK:
-               case I2C_SMBUS_I2C_BLOCK_BROKEN:
-               default:
-                       __entry->len = 0;
-               }
-                      ),
-       TP_printk("i2c-%d a=%03x f=%04x c=%x %s l=%u [%*phD]",
-                 __entry->adapter_nr,
-                 __entry->addr,
-                 __entry->flags,
-                 __entry->command,
-                 __print_symbolic(__entry->protocol,
-                                  { I2C_SMBUS_QUICK,           "QUICK" },
-                                  { I2C_SMBUS_BYTE,            "BYTE"  },
-                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
-                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
-                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
-                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
-                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
-                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
-                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" }),
-                 __entry->len,
-                 __entry->len, __entry->buf
-                 ));
-
-/*
- * i2c_smbus_xfer() result
- */
-TRACE_EVENT(smbus_result,
-           TP_PROTO(const struct i2c_adapter *adap,
-                    u16 addr, unsigned short flags,
-                    char read_write, u8 command, int protocol,
-                    int res),
-           TP_ARGS(adap, addr, flags, read_write, command, protocol, res),
-           TP_STRUCT__entry(
-                   __field(int,        adapter_nr              )
-                   __field(__u16,      addr                    )
-                   __field(__u16,      flags                   )
-                   __field(__u8,       read_write              )
-                   __field(__u8,       command                 )
-                   __field(__s16,      res                     )
-                   __field(__u32,      protocol                )
-                            ),
-           TP_fast_assign(
-                   __entry->adapter_nr = adap->nr;
-                   __entry->addr = addr;
-                   __entry->flags = flags;
-                   __entry->read_write = read_write;
-                   __entry->command = command;
-                   __entry->protocol = protocol;
-                   __entry->res = res;
-                          ),
-           TP_printk("i2c-%d a=%03x f=%04x c=%x %s %s res=%d",
-                     __entry->adapter_nr,
-                     __entry->addr,
-                     __entry->flags,
-                     __entry->command,
-                     __print_symbolic(__entry->protocol,
-                                      { I2C_SMBUS_QUICK,               "QUICK" },
-                                      { I2C_SMBUS_BYTE,                "BYTE"  },
-                                      { I2C_SMBUS_BYTE_DATA,           "BYTE_DATA" },
-                                      { I2C_SMBUS_WORD_DATA,           "WORD_DATA" },
-                                      { I2C_SMBUS_PROC_CALL,           "PROC_CALL" },
-                                      { I2C_SMBUS_BLOCK_DATA,          "BLOCK_DATA" },
-                                      { I2C_SMBUS_I2C_BLOCK_BROKEN,    "I2C_BLOCK_BROKEN" },
-                                      { I2C_SMBUS_BLOCK_PROC_CALL,     "BLOCK_PROC_CALL" },
-                                      { I2C_SMBUS_I2C_BLOCK_DATA,      "I2C_BLOCK_DATA" }),
-                     __entry->read_write == I2C_SMBUS_WRITE ? "wr" : "rd",
-                     __entry->res
-                     ));
-
 #endif /* _TRACE_I2C_H */
 
 /* This part must be outside protection */
diff --git a/include/trace/events/smbus.h b/include/trace/events/smbus.h
new file mode 100644 (file)
index 0000000..d2fb6e1
--- /dev/null
@@ -0,0 +1,249 @@
+/* SMBUS message transfer tracepoints
+ *
+ * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM smbus
+
+#if !defined(_TRACE_SMBUS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SMBUS_H
+
+#include <linux/i2c.h>
+#include <linux/tracepoint.h>
+
+/*
+ * drivers/i2c/i2c-core-smbus.c
+ */
+
+/*
+ * i2c_smbus_xfer() write data or procedure call request
+ */
+TRACE_EVENT_CONDITION(smbus_write,
+       TP_PROTO(const struct i2c_adapter *adap,
+                u16 addr, unsigned short flags,
+                char read_write, u8 command, int protocol,
+                const union i2c_smbus_data *data),
+       TP_ARGS(adap, addr, flags, read_write, command, protocol, data),
+       TP_CONDITION(read_write == I2C_SMBUS_WRITE ||
+                    protocol == I2C_SMBUS_PROC_CALL ||
+                    protocol == I2C_SMBUS_BLOCK_PROC_CALL),
+       TP_STRUCT__entry(
+               __field(int,    adapter_nr              )
+               __field(__u16,  addr                    )
+               __field(__u16,  flags                   )
+               __field(__u8,   command                 )
+               __field(__u8,   len                     )
+               __field(__u32,  protocol                )
+               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
+       TP_fast_assign(
+               __entry->adapter_nr = adap->nr;
+               __entry->addr = addr;
+               __entry->flags = flags;
+               __entry->command = command;
+               __entry->protocol = protocol;
+
+               switch (protocol) {
+               case I2C_SMBUS_BYTE_DATA:
+                       __entry->len = 1;
+                       goto copy;
+               case I2C_SMBUS_WORD_DATA:
+               case I2C_SMBUS_PROC_CALL:
+                       __entry->len = 2;
+                       goto copy;
+               case I2C_SMBUS_BLOCK_DATA:
+               case I2C_SMBUS_BLOCK_PROC_CALL:
+               case I2C_SMBUS_I2C_BLOCK_DATA:
+                       __entry->len = data->block[0] + 1;
+               copy:
+                       memcpy(__entry->buf, data->block, __entry->len);
+                       break;
+               case I2C_SMBUS_QUICK:
+               case I2C_SMBUS_BYTE:
+               case I2C_SMBUS_I2C_BLOCK_BROKEN:
+               default:
+                       __entry->len = 0;
+               }
+                      ),
+       TP_printk("i2c-%d a=%03x f=%04x c=%x %s l=%u [%*phD]",
+                 __entry->adapter_nr,
+                 __entry->addr,
+                 __entry->flags,
+                 __entry->command,
+                 __print_symbolic(__entry->protocol,
+                                  { I2C_SMBUS_QUICK,           "QUICK" },
+                                  { I2C_SMBUS_BYTE,            "BYTE"  },
+                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
+                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
+                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
+                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
+                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
+                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
+                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" }),
+                 __entry->len,
+                 __entry->len, __entry->buf
+                 ));
+
+/*
+ * i2c_smbus_xfer() read data request
+ */
+TRACE_EVENT_CONDITION(smbus_read,
+       TP_PROTO(const struct i2c_adapter *adap,
+                u16 addr, unsigned short flags,
+                char read_write, u8 command, int protocol),
+       TP_ARGS(adap, addr, flags, read_write, command, protocol),
+       TP_CONDITION(!(read_write == I2C_SMBUS_WRITE ||
+                      protocol == I2C_SMBUS_PROC_CALL ||
+                      protocol == I2C_SMBUS_BLOCK_PROC_CALL)),
+       TP_STRUCT__entry(
+               __field(int,    adapter_nr              )
+               __field(__u16,  flags                   )
+               __field(__u16,  addr                    )
+               __field(__u8,   command                 )
+               __field(__u32,  protocol                )
+               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
+       TP_fast_assign(
+               __entry->adapter_nr = adap->nr;
+               __entry->addr = addr;
+               __entry->flags = flags;
+               __entry->command = command;
+               __entry->protocol = protocol;
+                      ),
+       TP_printk("i2c-%d a=%03x f=%04x c=%x %s",
+                 __entry->adapter_nr,
+                 __entry->addr,
+                 __entry->flags,
+                 __entry->command,
+                 __print_symbolic(__entry->protocol,
+                                  { I2C_SMBUS_QUICK,           "QUICK" },
+                                  { I2C_SMBUS_BYTE,            "BYTE"  },
+                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
+                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
+                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
+                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
+                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
+                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
+                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" })
+                 ));
+
+/*
+ * i2c_smbus_xfer() read data or procedure call reply
+ */
+TRACE_EVENT_CONDITION(smbus_reply,
+       TP_PROTO(const struct i2c_adapter *adap,
+                u16 addr, unsigned short flags,
+                char read_write, u8 command, int protocol,
+                const union i2c_smbus_data *data),
+       TP_ARGS(adap, addr, flags, read_write, command, protocol, data),
+       TP_CONDITION(read_write == I2C_SMBUS_READ),
+       TP_STRUCT__entry(
+               __field(int,    adapter_nr              )
+               __field(__u16,  addr                    )
+               __field(__u16,  flags                   )
+               __field(__u8,   command                 )
+               __field(__u8,   len                     )
+               __field(__u32,  protocol                )
+               __array(__u8, buf, I2C_SMBUS_BLOCK_MAX + 2)     ),
+       TP_fast_assign(
+               __entry->adapter_nr = adap->nr;
+               __entry->addr = addr;
+               __entry->flags = flags;
+               __entry->command = command;
+               __entry->protocol = protocol;
+
+               switch (protocol) {
+               case I2C_SMBUS_BYTE:
+               case I2C_SMBUS_BYTE_DATA:
+                       __entry->len = 1;
+                       goto copy;
+               case I2C_SMBUS_WORD_DATA:
+               case I2C_SMBUS_PROC_CALL:
+                       __entry->len = 2;
+                       goto copy;
+               case I2C_SMBUS_BLOCK_DATA:
+               case I2C_SMBUS_BLOCK_PROC_CALL:
+               case I2C_SMBUS_I2C_BLOCK_DATA:
+                       __entry->len = data->block[0] + 1;
+               copy:
+                       memcpy(__entry->buf, data->block, __entry->len);
+                       break;
+               case I2C_SMBUS_QUICK:
+               case I2C_SMBUS_I2C_BLOCK_BROKEN:
+               default:
+                       __entry->len = 0;
+               }
+                      ),
+       TP_printk("i2c-%d a=%03x f=%04x c=%x %s l=%u [%*phD]",
+                 __entry->adapter_nr,
+                 __entry->addr,
+                 __entry->flags,
+                 __entry->command,
+                 __print_symbolic(__entry->protocol,
+                                  { I2C_SMBUS_QUICK,           "QUICK" },
+                                  { I2C_SMBUS_BYTE,            "BYTE"  },
+                                  { I2C_SMBUS_BYTE_DATA,               "BYTE_DATA" },
+                                  { I2C_SMBUS_WORD_DATA,               "WORD_DATA" },
+                                  { I2C_SMBUS_PROC_CALL,               "PROC_CALL" },
+                                  { I2C_SMBUS_BLOCK_DATA,              "BLOCK_DATA" },
+                                  { I2C_SMBUS_I2C_BLOCK_BROKEN,        "I2C_BLOCK_BROKEN" },
+                                  { I2C_SMBUS_BLOCK_PROC_CALL, "BLOCK_PROC_CALL" },
+                                  { I2C_SMBUS_I2C_BLOCK_DATA,  "I2C_BLOCK_DATA" }),
+                 __entry->len,
+                 __entry->len, __entry->buf
+                 ));
+
+/*
+ * i2c_smbus_xfer() result
+ */
+TRACE_EVENT(smbus_result,
+           TP_PROTO(const struct i2c_adapter *adap,
+                    u16 addr, unsigned short flags,
+                    char read_write, u8 command, int protocol,
+                    int res),
+           TP_ARGS(adap, addr, flags, read_write, command, protocol, res),
+           TP_STRUCT__entry(
+                   __field(int,        adapter_nr              )
+                   __field(__u16,      addr                    )
+                   __field(__u16,      flags                   )
+                   __field(__u8,       read_write              )
+                   __field(__u8,       command                 )
+                   __field(__s16,      res                     )
+                   __field(__u32,      protocol                )
+                            ),
+           TP_fast_assign(
+                   __entry->adapter_nr = adap->nr;
+                   __entry->addr = addr;
+                   __entry->flags = flags;
+                   __entry->read_write = read_write;
+                   __entry->command = command;
+                   __entry->protocol = protocol;
+                   __entry->res = res;
+                          ),
+           TP_printk("i2c-%d a=%03x f=%04x c=%x %s %s res=%d",
+                     __entry->adapter_nr,
+                     __entry->addr,
+                     __entry->flags,
+                     __entry->command,
+                     __print_symbolic(__entry->protocol,
+                                      { I2C_SMBUS_QUICK,               "QUICK" },
+                                      { I2C_SMBUS_BYTE,                "BYTE"  },
+                                      { I2C_SMBUS_BYTE_DATA,           "BYTE_DATA" },
+                                      { I2C_SMBUS_WORD_DATA,           "WORD_DATA" },
+                                      { I2C_SMBUS_PROC_CALL,           "PROC_CALL" },
+                                      { I2C_SMBUS_BLOCK_DATA,          "BLOCK_DATA" },
+                                      { I2C_SMBUS_I2C_BLOCK_BROKEN,    "I2C_BLOCK_BROKEN" },
+                                      { I2C_SMBUS_BLOCK_PROC_CALL,     "BLOCK_PROC_CALL" },
+                                      { I2C_SMBUS_I2C_BLOCK_DATA,      "I2C_BLOCK_DATA" }),
+                     __entry->read_write == I2C_SMBUS_WRITE ? "wr" : "rd",
+                     __entry->res
+                     ));
+
+#endif /* _TRACE_SMBUS_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>