Since, qspi controller uses quad read. Configuring the command register, if the transfer of data needs dual or quad lines.
This patch has been done on top of the following patch[1], which is just the basic idea of adding dual/quad support in spi framework. $subject patch will undergo changes once the ongoing discussion in the community is freezed. This patch is posted to demonstrate how patch 1 of the series will support quad read. [1]: http://comments.gmane.org/gmane.linux.kernel.spi.devel/14047 Signed-off-by: Sourav Poddar <sourav.pod...@ti.com> --- drivers/spi/spi-ti-qspi.c | 22 ++++++++++++++++------ 1 files changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c index 73a1675..fac1722 100644 --- a/drivers/spi/spi-ti-qspi.c +++ b/drivers/spi/spi-ti-qspi.c @@ -265,18 +265,30 @@ static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t) static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t) { int wlen, count, ret; + unsigned cmd = qspi->cmd; count = t->len; wlen = t->bits_per_word; + switch (t->bitwidth) { + case SPI_BITWIDTH_QUAD: + cmd |= QSPI_RD_QUAD; + break; + case SPI_BITWIDTH_DUAL: + cmd |= QSPI_RD_DUAL; + break; + case SPI_BITWIDTH_SINGLE: + default: + cmd |= QSPI_RD_SNGL; + } + if (wlen == 8) { u8 *rxbuf; rxbuf = t->rx_buf; do { dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", qspi->cmd | QSPI_RD_SNGL, qspi->dc); - ti_qspi_write(qspi, qspi->cmd | QSPI_RD_SNGL, - QSPI_SPI_CMD_REG); + ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG); ret = wait_for_completion_timeout(&qspi->transfer_complete, QSPI_COMPLETION_TIMEOUT); if (ret == 0) { @@ -294,8 +306,7 @@ static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t) do { dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", qspi->cmd | QSPI_RD_SNGL, qspi->dc); - ti_qspi_write(qspi, qspi->cmd | QSPI_RD_SNGL, - QSPI_SPI_CMD_REG); + ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG); ret = wait_for_completion_timeout(&qspi->transfer_complete, QSPI_COMPLETION_TIMEOUT); if (ret == 0) { @@ -313,8 +324,7 @@ static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t) do { dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", qspi->cmd | QSPI_RD_SNGL, qspi->dc); - ti_qspi_write(qspi, qspi->cmd | QSPI_RD_SNGL, - QSPI_SPI_CMD_REG); + ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG); ret = wait_for_completion_timeout(&qspi->transfer_complete, QSPI_COMPLETION_TIMEOUT); if (ret == 0) { -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
