Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4d676fc5 authored by Bob Liu's avatar Bob Liu Committed by Grant Likely
Browse files

spi/bfin_spi: support for multiples of 8bits with hardware CS 



We can do multiples of 8bit transfers when using the hardware CS and a
little bit of magic, so make it work.

Signed-off-by: default avatarBob Liu <lliubbo@gmail.com>
Signed-off-by: default avatarMike Frysinger <vapier@gentoo.org>
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
parent b214b7bb

drivers/spi/spi_bfin5xx.c

+71 −32
Original line number Diff line number Diff line
@@ -425,6 +425,7 @@ static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id) 
	struct bfin_spi_slave_data *chip = drv_data->cur_chip;

	struct spi_message *msg = drv_data->cur_msg;

	int n_bytes = drv_data->n_bytes;

	int loop = 0;



	/* wait until transfer finished. */

	while (!(read_STAT(drv_data) & BIT_STAT_RXS))
@@ -435,10 +436,15 @@ static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id) 
		/* last read */

		if (drv_data->rx) {

			dev_dbg(&drv_data->pdev->dev, "last read\n");

			if (n_bytes == 2)

				*(u16 *) (drv_data->rx) = read_RDBR(drv_data);

			else if (n_bytes == 1)

				*(u8 *) (drv_data->rx) = read_RDBR(drv_data);

			if (n_bytes % 2) {

				u16 *buf = (u16 *)drv_data->rx;

				for (loop = 0; loop < n_bytes / 2; loop++)

					*buf++ = read_RDBR(drv_data);

			} else {

				u8 *buf = (u8 *)drv_data->rx;

				for (loop = 0; loop < n_bytes; loop++)

					*buf++ = read_RDBR(drv_data);

			}

			drv_data->rx += n_bytes;

		}
@@ -458,29 +464,53 @@ static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id) 
	if (drv_data->rx && drv_data->tx) {

		/* duplex */

		dev_dbg(&drv_data->pdev->dev, "duplex: write_TDBR\n");

		if (drv_data->n_bytes == 2) {

			*(u16 *) (drv_data->rx) = read_RDBR(drv_data);

			write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));

		} else if (drv_data->n_bytes == 1) {

			*(u8 *) (drv_data->rx) = read_RDBR(drv_data);

			write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));

		if (n_bytes % 2) {

			u16 *buf = (u16 *)drv_data->rx;

			u16 *buf2 = (u16 *)drv_data->tx;

			for (loop = 0; loop < n_bytes / 2; loop++) {

				*buf++ = read_RDBR(drv_data);

				write_TDBR(drv_data, *buf2++);

			}

		} else {

			u8 *buf = (u8 *)drv_data->rx;

			u8 *buf2 = (u8 *)drv_data->tx;

			for (loop = 0; loop < n_bytes; loop++) {

				*buf++ = read_RDBR(drv_data);

				write_TDBR(drv_data, *buf2++);

			}

		}

	} else if (drv_data->rx) {

		/* read */

		dev_dbg(&drv_data->pdev->dev, "read: write_TDBR\n");

		if (drv_data->n_bytes == 2)

			*(u16 *) (drv_data->rx) = read_RDBR(drv_data);

		else if (drv_data->n_bytes == 1)

			*(u8 *) (drv_data->rx) = read_RDBR(drv_data);

		if (n_bytes % 2) {

			u16 *buf = (u16 *)drv_data->rx;

			for (loop = 0; loop < n_bytes / 2; loop++) {

				*buf++ = read_RDBR(drv_data);

				write_TDBR(drv_data, chip->idle_tx_val);

			}

		} else {

			u8 *buf = (u8 *)drv_data->rx;

			for (loop = 0; loop < n_bytes; loop++) {

				*buf++ = read_RDBR(drv_data);

				write_TDBR(drv_data, chip->idle_tx_val);

			}

		}

	} else if (drv_data->tx) {

		/* write */

		dev_dbg(&drv_data->pdev->dev, "write: write_TDBR\n");

		bfin_spi_dummy_read(drv_data);

		if (drv_data->n_bytes == 2)

			write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));

		else if (drv_data->n_bytes == 1)

			write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));

		if (n_bytes % 2) {

			u16 *buf = (u16 *)drv_data->tx;

			for (loop = 0; loop < n_bytes / 2; loop++) {

				read_RDBR(drv_data);

				write_TDBR(drv_data, *buf++);

			}

		} else {

			u8 *buf = (u8 *)drv_data->tx;

			for (loop = 0; loop < n_bytes; loop++) {

				read_RDBR(drv_data);

				write_TDBR(drv_data, *buf++);

			}

		}

	}



	if (drv_data->tx)
@@ -651,16 +681,16 @@ static void bfin_spi_pump_transfers(unsigned long data) 


	/* Bits per word setup */

	bits_per_word = transfer->bits_per_word ? : message->spi->bits_per_word;

	if (bits_per_word == 8) {

		drv_data->n_bytes = 1;

		drv_data->len = transfer->len;

		cr_width = 0;

		drv_data->ops = &bfin_bfin_spi_transfer_ops_u8;

	} else if (bits_per_word == 16) {

		drv_data->n_bytes = 2;

	if ((bits_per_word > 0) && (bits_per_word % 16 == 0)) {

		drv_data->n_bytes = bits_per_word/8;

		drv_data->len = (transfer->len) >> 1;

		cr_width = BIT_CTL_WORDSIZE;

		drv_data->ops = &bfin_bfin_spi_transfer_ops_u16;

	} else if ((bits_per_word > 0) && (bits_per_word % 8 == 0)) {

		drv_data->n_bytes = bits_per_word/8;

		drv_data->len = transfer->len;

		cr_width = 0;

		drv_data->ops = &bfin_bfin_spi_transfer_ops_u8;

	} else {

		dev_err(&drv_data->pdev->dev, "transfer: unsupported bits_per_word\n");

		message->status = -EINVAL;
@@ -815,10 +845,19 @@ static void bfin_spi_pump_transfers(unsigned long data) 
		if (drv_data->tx == NULL)

			write_TDBR(drv_data, chip->idle_tx_val);

		else {

			if (bits_per_word == 8)

				write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));

			else

				write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));

			int loop;

			if (bits_per_word % 16 == 0) {

				u16 *buf = (u16 *)drv_data->tx;

				for (loop = 0; loop < bits_per_word / 16;

						loop++) {

					write_TDBR(drv_data, *buf++);

				}

			} else if (bits_per_word % 8 == 0) {

				u8 *buf = (u8 *)drv_data->tx;

				for (loop = 0; loop < bits_per_word / 8; loop++)

					write_TDBR(drv_data, *buf++);

			}



			drv_data->tx += drv_data->n_bytes;

		}
@@ -1031,7 +1070,7 @@ static int bfin_spi_setup(struct spi_device *spi) 
		chip->ctl_reg &= bfin_ctl_reg;

	}



	if (spi->bits_per_word != 8 && spi->bits_per_word != 16) {

	if (spi->bits_per_word % 8) {

		dev_err(&spi->dev, "%d bits_per_word is not supported\n",

				spi->bits_per_word);

		goto error;