From: Justin Chen justinpopo6@gmail.com
commit 4df3bea7f9d2ddd9ac2c29ba945c7c4db2def29c upstream.
Currently we set the tx/rx buffer to 0xff when NULL. This causes problems with some spi slaves where 0xff is a valid command. Looking at other drivers, the tx/rx buffer is usually set to 0x00 when NULL. Following this convention solves the issue.
Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver") Signed-off-by: Justin Chen justinpopo6@gmail.com Signed-off-by: Kamal Dasu kdasu.kdev@gmail.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200420190853.45614-6-kdasu.kdev@gmail.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/spi/spi-bcm-qspi.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -670,7 +670,7 @@ static void read_from_hw(struct bcm_qspi if (buf) buf[tp.byte] = read_rxram_slot_u8(qspi, slot); dev_dbg(&qspi->pdev->dev, "RD %02x\n", - buf ? buf[tp.byte] : 0xff); + buf ? buf[tp.byte] : 0x0); } else { u16 *buf = tp.trans->rx_buf;
@@ -678,7 +678,7 @@ static void read_from_hw(struct bcm_qspi buf[tp.byte / 2] = read_rxram_slot_u16(qspi, slot); dev_dbg(&qspi->pdev->dev, "RD %04x\n", - buf ? buf[tp.byte] : 0xffff); + buf ? buf[tp.byte / 2] : 0x0); }
update_qspi_trans_byte_count(qspi, &tp, @@ -733,13 +733,13 @@ static int write_to_hw(struct bcm_qspi * while (!tstatus && slot < MSPI_NUM_CDRAM) { if (tp.trans->bits_per_word <= 8) { const u8 *buf = tp.trans->tx_buf; - u8 val = buf ? buf[tp.byte] : 0xff; + u8 val = buf ? buf[tp.byte] : 0x00;
write_txram_slot_u8(qspi, slot, val); dev_dbg(&qspi->pdev->dev, "WR %02x\n", val); } else { const u16 *buf = tp.trans->tx_buf; - u16 val = buf ? buf[tp.byte / 2] : 0xffff; + u16 val = buf ? buf[tp.byte / 2] : 0x0000;
write_txram_slot_u16(qspi, slot, val); dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);