i2c: iproc: Fix i2c master read more than 63 bytes

Use SMBUS_MASTER_DATA_READ.MASTER_RD_STATUS bit to check for RX
FIFO empty condition because SMBUS_MASTER_FIFO_CONTROL.MASTER_RX_PKT_COUNT
is not updated for read >= 64 bytes. This fixes the issue when trying to
read from the I2C slave more than 63 bytes.

Fixes: c24b8d574b ("i2c: iproc: Extend I2C read up to 255 bytes")
Cc: stable@kernel.org
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Rayagonda Kokatanur 2019-07-24 13:58:27 +05:30 committed by Wolfram Sang
parent 3a5ff11be8
commit fd01eecdf9

View File

@ -392,16 +392,18 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
{
struct i2c_msg *msg = iproc_i2c->msg;
uint32_t val;
/* Read valid data from RX FIFO */
while (iproc_i2c->rx_bytes < msg->len) {
if (!((iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET) >> M_FIFO_RX_CNT_SHIFT)
& M_FIFO_RX_CNT_MASK))
val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
/* rx fifo empty */
if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
break;
msg->buf[iproc_i2c->rx_bytes] =
(iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET) >>
M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
(val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
iproc_i2c->rx_bytes++;
}
}