Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756097Ab3HAOAh (ORCPT ); Thu, 1 Aug 2013 10:00:37 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:56685 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755979Ab3HAOAe (ORCPT ); Thu, 1 Aug 2013 10:00:34 -0400 From: Sourav Poddar To: , , CC: , , , , Sourav Poddar Subject: [RFC/PATCH 2/2] driver: spi: Add quad spi read support Date: Thu, 1 Aug 2013 19:30:02 +0530 Message-ID: <1375365602-31321-3-git-send-email-sourav.poddar@ti.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1375365602-31321-1-git-send-email-sourav.poddar@ti.com> References: <1375365602-31321-1-git-send-email-sourav.poddar@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2824 Lines: 85 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 --- 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 majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/