Commit e24a4d1e authored by Anton Vorontsov's avatar Anton Vorontsov Committed by Linus Torvalds
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spi_mpc83xx: in "QE mode", use sysclk/2 



For MPC8349E input to the SPI Baud Rate Generator is SYSCLK, but it's
SYSCLK/2 for MPC8323E (SPI in QE).  Fix this, and remove confusion by
renaming the mpc83xx_spi->sysclk member as mpc83xx_spi->spibrg.

Signed-off-by: default avatarAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8dfe9c21

drivers/spi/spi_mpc83xx.c

+13 −8
Original line number Diff line number Diff line
@@ -86,7 +86,7 @@ struct mpc83xx_spi { 


	unsigned nsecs;		/* (clock cycle time)/2 */



	u32 sysclk;

	u32 spibrg;		/* SPIBRG input clock */

	u32 rx_shift;		/* RX data reg shift when in qe mode */

	u32 tx_shift;		/* TX data reg shift when in qe mode */
@@ -169,17 +169,18 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value) 


		regval |= SPMODE_LEN(len);



		if ((mpc83xx_spi->sysclk / spi->max_speed_hz) >= 64) {

			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 64);

		if ((mpc83xx_spi->spibrg / spi->max_speed_hz) >= 64) {

			u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 64);

			if (pm > 0x0f) {

				printk(KERN_WARNING "MPC83xx SPI: SPICLK can't be less then a SYSCLK/1024!\n"

						"Requested SPICLK is %d Hz. Will use %d Hz instead.\n",

						spi->max_speed_hz, mpc83xx_spi->sysclk / 1024);

				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 {

			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 4);

			u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);

			regval |= SPMODE_PM(pm);

		}
@@ -429,13 +430,17 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev) 
	mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect;

	mpc83xx_spi->bitbang.setup_transfer = mpc83xx_spi_setup_transfer;

	mpc83xx_spi->bitbang.txrx_bufs = mpc83xx_spi_bufs;

	mpc83xx_spi->sysclk = pdata->sysclk;

	mpc83xx_spi->activate_cs = pdata->activate_cs;

	mpc83xx_spi->deactivate_cs = pdata->deactivate_cs;

	mpc83xx_spi->qe_mode = pdata->qe_mode;

	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->spibrg = pdata->sysclk / 2;

	else

		mpc83xx_spi->spibrg = pdata->sysclk;



	mpc83xx_spi->rx_shift = 0;

	mpc83xx_spi->tx_shift = 0;

	if (mpc83xx_spi->qe_mode) {

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