In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data in one transaction, so the size of data to be write/read to/from TXDATAx/RXDATAx must be less than or equal 32 bytes at a time. Test on pinky board, elan receive 158 bytes data. Signed-off-by: Addy Ke <addy.ke@xxxxxxxxxxxxxx> --- drivers/i2c/busses/i2c-rk3x.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index 69e1185..dc0aa64 100644 --- a/drivers/i2c/busses/i2c-rk3x.c +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -323,6 +323,9 @@ static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd) /* ack interrupt */ i2c_writel(i2c, REG_INT_MBRF, REG_IPD); + /* Can only handle a maximum of 32 bytes at a time */ + len = (len > 32) ? 32 : len; + /* read the data from receive buffer */ for (i = 0; i < len; ++i) { if (i % 4 == 0) -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html