From f53f15ba5a852171eccf940b22530152450a045c Mon Sep 17 00:00:00 2001 From: Liguang Zhang Date: Thu, 25 Feb 2021 22:26:31 +0800 Subject: i2c: designware: Get right data length 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 real data length. Signed-off-by: Liguang Zhang Reviewed-by: Andy Shevchenko Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-designware-core.h | 2 ++ drivers/i2c/busses/i2c-designware-master.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 85307cfa7109..5392b82f68a4 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -38,6 +38,8 @@ #define DW_IC_CON_TX_EMPTY_CTRL BIT(8) #define DW_IC_CON_RX_FIFO_FULL_HLD_CTRL BIT(9) +#define DW_IC_DATA_CMD_DAT GENMASK(7, 0) + /* * Registers offset */ diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index d6425ad6e6a3..dd27b9dbe931 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 & DW_IC_DATA_CMD_DAT) <= I2C_SMBUS_BLOCK_MAX && tmp > 0) { len = i2c_dw_recv_len(dev, tmp); } *buf++ = tmp; -- cgit v1.2.3