| Message ID | 20210225023528.121135-1-zhangliguang@linux.alibaba.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | i2c: designware: Get right data length | expand |
On Thu, Feb 25, 2021 at 10:35:28AM +0800, Liguang Zhang wrote: > IC_DATA_CMD[11] indicates the first data byte received after the address > phase for receive transfer in Master receiver or Slave receiver mode, > this bit was set in some transfer flow. IC_DATA_CMD[7:0] contains the > data to be transmitted or received on the I2C bus, so we should use the > lower 8 bits to get the right data length. Thanks for the report and fix! My comments below. > Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com> > --- > drivers/i2c/busses/i2c-designware-master.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c > index d6425ad6e6a3..c3cf76f6c607 100644 > --- a/drivers/i2c/busses/i2c-designware-master.c > +++ b/drivers/i2c/busses/i2c-designware-master.c > @@ -432,7 +432,7 @@ i2c_dw_read(struct dw_i2c_dev *dev) > regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); > /* Ensure length byte is a valid value */ > if (flags & I2C_M_RECV_LEN && > - tmp <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { > + (tmp & 0xff) <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { Can we rather describe this as #define DW_IC_DATA_CMD_DAT GENMASK(7, 0) in *.h file and... (tmp & DW_IC_DATA_CMD_DAT) <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { ...here? > len = i2c_dw_recv_len(dev, tmp); > } > *buf++ = tmp; > -- > 2.19.1.6.gb485710b >
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index d6425ad6e6a3..c3cf76f6c607 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -432,7 +432,7 @@ i2c_dw_read(struct dw_i2c_dev *dev) regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); /* Ensure length byte is a valid value */ if (flags & I2C_M_RECV_LEN && - tmp <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { + (tmp & 0xff) <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { len = i2c_dw_recv_len(dev, tmp); } *buf++ = tmp;
IC_DATA_CMD[11] indicates the first data byte received after the address phase for receive transfer in Master receiver or Slave receiver mode, this bit was set in some transfer flow. IC_DATA_CMD[7:0] contains the data to be transmitted or received on the I2C bus, so we should use the lower 8 bits to get the right data length. Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com> --- drivers/i2c/busses/i2c-designware-master.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)