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: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 0c16a2b..fe69e94 100644 (file)
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -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) {