Commit 8263cb33 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Mark Brown
Browse files

spi: fsl-espi: add support for dual output read mode 



This patch adds support for dual output read mode.

It was successfully tested on a P1014-based device with S25FL128S
SPINOR flash. With 50MHz SPI clock the read rate is 11MByte/s.

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent aca75157

drivers/spi/spi-fsl-espi.c

+12 −1
Original line number Diff line number Diff line
@@ -334,6 +334,8 @@ static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) 
		mpc8xxx_spi->tx_len = mpc8xxx_spi->rxskip;

		mpc8xxx_spi->rx_len = t->len - mpc8xxx_spi->rxskip;

		mpc8xxx_spi->rx = t->rx_buf + mpc8xxx_spi->rxskip;

		if (t->rx_nbits == SPI_NBITS_DUAL)

			spcom |= SPCOM_DO;

	}



	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM, spcom);
@@ -369,6 +371,11 @@ static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans) 
	int ret;



	mspi->rxskip = fsl_espi_check_rxskip_mode(m);

	if (trans->rx_nbits == SPI_NBITS_DUAL && !mspi->rxskip) {

		dev_err(mspi->dev, "Dual output mode requires RXSKIP mode!\n");

		return -EINVAL;

	}



	fsl_espi_copy_to_buf(m, mspi);

	fsl_espi_setup_transfer(spi, trans);
@@ -387,7 +394,7 @@ static int fsl_espi_do_one_msg(struct spi_master *master, 
			       struct spi_message *m)

{

	struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);

	unsigned int delay_usecs = 0;

	unsigned int delay_usecs = 0, rx_nbits = 0;

	struct spi_transfer *t, trans = {};

	int ret;
@@ -398,6 +405,8 @@ static int fsl_espi_do_one_msg(struct spi_master *master, 
	list_for_each_entry(t, &m->transfers, transfer_list) {

		if (t->delay_usecs > delay_usecs)

			delay_usecs = t->delay_usecs;

		if (t->rx_nbits > rx_nbits)

			rx_nbits = t->rx_nbits;

	}



	t = list_first_entry(&m->transfers, struct spi_transfer,
@@ -409,6 +418,7 @@ static int fsl_espi_do_one_msg(struct spi_master *master, 
	trans.delay_usecs = delay_usecs;

	trans.tx_buf = mspi->local_buf;

	trans.rx_buf = mspi->local_buf;

	trans.rx_nbits = rx_nbits;



	if (trans.len)

		ret = fsl_espi_trans(m, &trans);
@@ -580,6 +590,7 @@ static int fsl_espi_probe(struct device *dev, struct resource *mem, 


	mpc8xxx_spi_probe(dev, mem, irq);



	master->mode_bits |= SPI_RX_DUAL;

	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);

	master->setup = fsl_espi_setup;

	master->cleanup = fsl_espi_cleanup;

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