Ejemplo n.º 1
0
static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
{
	struct mpc83xx_spi *mpc83xx_spi;
	u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0;

	mpc83xx_spi = spi_master_get_devdata(spi->master);

	if (value == BITBANG_CS_INACTIVE) {
		if (mpc83xx_spi->deactivate_cs)
			mpc83xx_spi->deactivate_cs(spi->chip_select, pol);
	}

	if (value == BITBANG_CS_ACTIVE) {
		u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
		u32 len = spi->bits_per_word;
		if (len == 32)
			len = 0;
		else
			len = len - 1;

		/* mask out bits we are going to set */
		regval &= ~0x38ff0000;

		if (spi->mode & SPI_CPHA)
			regval |= SPMODE_CP_BEGIN_EDGECLK;
		if (spi->mode & SPI_CPOL)
			regval |= SPMODE_CI_INACTIVEHIGH;

		regval |= SPMODE_LEN(len);

		if ((mpc83xx_spi->sysclk / spi->max_speed_hz) >= 64) {
			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 64);
			regval |= SPMODE_PM(pm) | SPMODE_DIV16;
		} else {
			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 4);
			regval |= SPMODE_PM(pm);
		}

		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
		if (mpc83xx_spi->activate_cs)
			mpc83xx_spi->activate_cs(spi->chip_select, pol);
	}
}
Ejemplo n.º 2
0
static
int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
	struct mpc83xx_spi *mpc83xx_spi;
	u32 regval;
	u8 bits_per_word;
	u32 hz;

	mpc83xx_spi = spi_master_get_devdata(spi->master);

	if (t) {
		bits_per_word = t->bits_per_word;
		hz = t->speed_hz;
	} else {
		bits_per_word = 0;
		hz = 0;
	}

	/* spi_transfer level calls that work per-word */
	if (!bits_per_word)
		bits_per_word = spi->bits_per_word;

	/* Make sure its a bit width we support [4..16, 32] */
	if ((bits_per_word < 4)
	    || ((bits_per_word > 16) && (bits_per_word != 32)))
		return -EINVAL;

	mpc83xx_spi->rx_shift = 0;
	mpc83xx_spi->tx_shift = 0;
	if (bits_per_word <= 8) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
		if (mpc83xx_spi->qe_mode) {
			mpc83xx_spi->rx_shift = 16;
			mpc83xx_spi->tx_shift = 24;
		}
	} else if (bits_per_word <= 16) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u16;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u16;
		if (mpc83xx_spi->qe_mode) {
			mpc83xx_spi->rx_shift = 16;
			mpc83xx_spi->tx_shift = 16;
		}
	} else if (bits_per_word <= 32) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u32;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u32;
	} else
		return -EINVAL;

	if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) {
		mpc83xx_spi->tx_shift = 0;
		if (bits_per_word <= 8)
			mpc83xx_spi->rx_shift = 8;
		else
			mpc83xx_spi->rx_shift = 0;
	}

	/* nsecs = (clock period)/2 */
	if (!hz)
		hz = spi->max_speed_hz;
	mpc83xx_spi->nsecs = (1000000000 / 2) / hz;
	if (mpc83xx_spi->nsecs > MAX_UDELAY_MS * 1000)
		return -EINVAL;

	if (bits_per_word == 32)
		bits_per_word = 0;
	else
		bits_per_word = bits_per_word - 1;

	regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);

	/* mask out bits we are going to set */
	regval &= ~(SPMODE_LEN(0xF) | SPMODE_REV);
	regval |= SPMODE_LEN(bits_per_word);
	if (!(spi->mode & SPI_LSB_FIRST))
		regval |= SPMODE_REV;

	/* Turn off SPI unit prior changing mode */
	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);

	return 0;
}
Ejemplo n.º 3
0
static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
{
	struct mpc83xx_spi *mpc83xx_spi;
	u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0;

	mpc83xx_spi = spi_master_get_devdata(spi->master);

	if (value == BITBANG_CS_INACTIVE) {
		if (mpc83xx_spi->deactivate_cs)
			mpc83xx_spi->deactivate_cs(spi->chip_select, pol);
	}

	if (value == BITBANG_CS_ACTIVE) {
		u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
		u32 len = spi->bits_per_word;
		u8 pm;

		if (len == 32)
			len = 0;
		else
			len = len - 1;

		/* mask out bits we are going to set */
		regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
				| SPMODE_LEN(0xF) | SPMODE_DIV16
				| SPMODE_PM(0xF) | SPMODE_REV | SPMODE_LOOP);

		if (spi->mode & SPI_CPHA)
			regval |= SPMODE_CP_BEGIN_EDGECLK;
		if (spi->mode & SPI_CPOL)
			regval |= SPMODE_CI_INACTIVEHIGH;
		if (!(spi->mode & SPI_LSB_FIRST))
			regval |= SPMODE_REV;
		if (spi->mode & SPI_LOOP)
			regval |= SPMODE_LOOP;

		regval |= SPMODE_LEN(len);

		if ((mpc83xx_spi->spibrg / spi->max_speed_hz) >= 64) {
			pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 64) - 1;
			if (pm > 0x0f) {
				dev_err(&spi->dev, "Requested speed is too "
					"low: %d Hz. Will use %d Hz instead.\n",
					spi->max_speed_hz,
					mpc83xx_spi->spibrg / 1024);
				pm = 0x0f;
			}
			regval |= SPMODE_PM(pm) | SPMODE_DIV16;
		} else {
			pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);
			if (pm)
				pm--;
			regval |= SPMODE_PM(pm);
		}

		/* Turn off SPI unit prior changing mode */
		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
		if (mpc83xx_spi->activate_cs)
			mpc83xx_spi->activate_cs(spi->chip_select, pol);
	}
}
Ejemplo n.º 4
0
static
int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
	struct mpc83xx_spi *mpc83xx_spi;
	u32 regval;
	u8 bits_per_word;
	u32 hz;

	mpc83xx_spi = spi_master_get_devdata(spi->master);

	if (t) {
		bits_per_word = t->bits_per_word;
		hz = t->speed_hz;
	} else {
		bits_per_word = 0;
		hz = 0;
	}

	/* spi_transfer level calls that work per-word */
	if (!bits_per_word)
		bits_per_word = spi->bits_per_word;

	/* Make sure its a bit width we support [4..16, 32] */
	if ((bits_per_word < 4)
	    || ((bits_per_word > 16) && (bits_per_word != 32)))
		return -EINVAL;

	if (bits_per_word <= 8) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
	} else if (bits_per_word <= 16) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u16;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u16;
	} else if (bits_per_word <= 32) {
		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u32;
		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u32;
	} else
		return -EINVAL;

	/* nsecs = (clock period)/2 */
	if (!hz)
		hz = spi->max_speed_hz;
	mpc83xx_spi->nsecs = (1000000000 / 2) / hz;
	if (mpc83xx_spi->nsecs > MAX_UDELAY_MS * 1000)
		return -EINVAL;

	if (bits_per_word == 32)
		bits_per_word = 0;
	else
		bits_per_word = bits_per_word - 1;

	regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);

	/* Mask out bits_per_wordgth */
	regval &= 0xff0fffff;
	regval |= SPMODE_LEN(bits_per_word);

	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);

	return 0;
}