Fix expression for residual bytes(less than word) transfer in I2C PIO mode RX/TX.
Signed-off-by: Bitan Biswas <[email protected]> --- drivers/i2c/busses/i2c-tegra.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 4dfb4c1..0596c12 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -514,7 +514,8 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) * If there is a partial word at the end of buf, handle it manually to * prevent overwriting past the end of buf */ - if (rx_fifo_avail > 0 && buf_remaining > 0) { + if (rx_fifo_avail > 0 && + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) { BUG_ON(buf_remaining > 3); val = i2c_readl(i2c_dev, I2C_RX_FIFO); val = cpu_to_le32(val); @@ -557,11 +558,10 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) words_to_transfer = tx_fifo_avail; /* - * Update state before writing to FIFO. If this casues us + * Update state before writing to FIFO. If this causes us * to finish writing all bytes (AKA buf_remaining goes to 0) we * have a potential for an interrupt (PACKET_XFER_COMPLETE is - * not maskable). We need to make sure that the isr sees - * buf_remaining as 0 and doesn't call us back re-entrantly. + * not maskable). */ buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; tx_fifo_avail -= words_to_transfer; @@ -580,7 +580,8 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) * prevent reading past the end of buf, which could cross a page * boundary and fault. */ - if (tx_fifo_avail > 0 && buf_remaining > 0) { + if (tx_fifo_avail > 0 && + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) { BUG_ON(buf_remaining > 3); memcpy(&val, buf, buf_remaining); val = le32_to_cpu(val); -- 2.7.4
