spi_mpc83xx.c: support QE enabled 83xx CPU's like mpc832x

Quicc Engine enabled mpc83xx CPU's has a somewhat different HW interface to
the SPI controller.  This patch adds a qe_mode knob that sees to that
needed adaptions are performed.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
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>

2 files changed, 30 insertions, 4 deletions

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index bbd51bc88a60..3295cfcc9f20 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -47,6 +47,7 @@ struct mpc83xx_spi_reg {
 #define SPMODE_ENABLE           (1 << 24)
 #define SPMODE_LEN(x)           ((x) << 20)
 #define SPMODE_PM(x)            ((x) << 16)
+#define SPMODE_OP               (1 << 14)
 
 /*
  * Default for SPI Mode:
@@ -85,6 +86,11 @@ struct mpc83xx_spi {
         unsigned nsecs;         /* (clock cycle time)/2 */
 
         u32 sysclk;
+        u32 rx_shift;           /* RX data reg shift when in qe mode */
+        u32 tx_shift;           /* TX data reg shift when in qe mode */
+
+        bool qe_mode;
+
         void (*activate_cs) (u8 cs, u8 polarity);
         void (*deactivate_cs) (u8 cs, u8 polarity);
 };
@@ -103,7 +109,7 @@ static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg)
 void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \
 {                                                                         \
         type * rx = mpc83xx_spi->rx;                                      \
-        *rx++ = (type)data;                                               \
+        *rx++ = (type)(data >> mpc83xx_spi->rx_shift);                    \
         mpc83xx_spi->rx = rx;                                             \
 }
 
@@ -114,7 +120,7 @@ u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi)	\
         const type * tx = mpc83xx_spi->tx;                      \
         if (!tx)                                                \
                 return 0;                                       \
-        data = *tx++;                                           \
+        data = *tx++ << mpc83xx_spi->tx_shift;                  \
         mpc83xx_spi->tx = tx;                                   \
         return data;                                            \
 }
@@ -203,12 +209,22 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
             || ((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;
@@ -386,7 +402,6 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
                 ret = -ENODEV;
                 goto free_master;
         }
-
         mpc83xx_spi = spi_master_get_devdata(master);
         mpc83xx_spi->bitbang.master = spi_master_get(master);
         mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect;
@@ -395,9 +410,17 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
         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;
 
+        mpc83xx_spi->rx_shift = 0;
+        mpc83xx_spi->tx_shift = 0;
+        if (mpc83xx_spi->qe_mode) {
+                mpc83xx_spi->rx_shift = 16;
+                mpc83xx_spi->tx_shift = 24;
+        }
+
         mpc83xx_spi->bitbang.master->setup = mpc83xx_spi_setup;
         init_completion(&mpc83xx_spi->done);
 
@@ -432,6 +455,9 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
 
         /* Enable SPI interface */
         regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+        if (pdata->qe_mode)
+                regval |= SPMODE_OP;
+
         mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
 
         ret = spi_bitbang_start(&mpc83xx_spi->bitbang);
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index 12e631f0fb77..695741b0e420 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -112,7 +112,7 @@ struct fsl_usb2_platform_data {
 struct fsl_spi_platform_data {
         u32     initial_spmode; /* initial SPMODE value */
         u16     bus_num;
-
+        bool    qe_mode;
         /* board specific information */
         u16     max_chipselect;
         void    (*activate_cs)(u8 cs, u8 polarity);