Add support for SMBUS_READ_BLOCK_DATA to the i2c-mpc bus driver. Required to support the PMBus zl6100 driver with i2c-mpc.
Reported-by: Tang Yuantian <[email protected]> Cc: Tang Yuantian <[email protected]> Signed-off-by: Guenter Roeck <[email protected]> --- drivers/i2c/busses/i2c-mpc.c | 33 +++++++++++++++++++++++++-------- 1 files changed, 25 insertions(+), 8 deletions(-) diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index 107397a..77aade7 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -454,7 +454,7 @@ static int mpc_write(struct mpc_i2c *i2c, int target, } static int mpc_read(struct mpc_i2c *i2c, int target, - u8 *data, int length, int restart) + u8 *data, int length, int restart, bool block) { unsigned timeout = i2c->adap.timeout; int i, result; @@ -470,7 +470,7 @@ static int mpc_read(struct mpc_i2c *i2c, int target, return result; if (length) { - if (length == 1) + if (length == 1 && !block) writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); else writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA); @@ -479,17 +479,28 @@ static int mpc_read(struct mpc_i2c *i2c, int target, } for (i = 0; i < length; i++) { + u8 byte; + result = i2c_wait(i2c, timeout, 0); if (result < 0) return result; + byte = readb(i2c->base + MPC_I2C_DR); + /* + * Adjust length if first received byte is length + */ + if (i == 0 && block) { + if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + length += byte; + } + data[i] = byte; /* Generate txack on next to last byte */ if (i == length - 2) writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); /* Do not generate stop on last byte */ if (i == length - 1) writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX); - data[i] = readb(i2c->base + MPC_I2C_DR); } return length; @@ -532,12 +543,17 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) "Doing %s %d bytes to 0x%02x - %d of %d messages\n", pmsg->flags & I2C_M_RD ? "read" : "write", pmsg->len, pmsg->addr, i + 1, num); - if (pmsg->flags & I2C_M_RD) - ret = - mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); - else + if (pmsg->flags & I2C_M_RD) { + bool block = pmsg->flags & I2C_M_RECV_LEN; + + ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i, + block); + if (block && ret > 0) + pmsg->len = ret; + } else { ret = mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); + } } mpc_i2c_stop(i2c); return (ret < 0) ? ret : num; @@ -545,7 +561,8 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) static u32 mpc_functionality(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA; } static const struct i2c_algorithm mpc_algo = { -- 1.7.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
