spi/pxa2xx: add support for Intel Low Power Subsystem SPI

Intel LPSS SPI is pretty much the same as the PXA27xx SPI except that it
has few additional features over the original:

	o FIFO depth is 256 entries
	o RX FIFO has one watermark
	o TX FIFO has two watermarks, low and high
	o chip select can be controlled by writing to a register

The new FIFO registers follow immediately the PXA27xx registers but then there
are some additional LPSS private registers at offset 1k or 2k from the base
address. For these private registers we add new accessors that take advantage
of drv_data->lpss_base once it is resolved.

We add a new type LPSS_SSP that can be used to distinguish the LPSS devices
from others.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/pxa2xx_ssp.h b/include/linux/pxa2xx_ssp.h
index 065e7f6c3ad7..467cc6307b62 100644
--- a/include/linux/pxa2xx_ssp.h
+++ b/include/linux/pxa2xx_ssp.h
@@ -155,6 +155,14 @@
 #define SSACD_ACDS(x)           ((x) << 0)      /* Audio clock divider select */
 #define SSACD_SCDX8             (1 << 7)        /* SYSCLK division ratio select */
 
+/* LPSS SSP */
+#define SSITF                   0x44            /* TX FIFO trigger level */
+#define SSITF_TxLoThresh(x)     (((x) - 1) << 8)
+#define SSITF_TxHiThresh(x)     ((x) - 1)
+
+#define SSIRF                   0x48            /* RX FIFO trigger level */
+#define SSIRF_RxThresh(x)       ((x) - 1)
+
 enum pxa_ssp_type {
         SSP_UNDEFINED = 0,
         PXA25x_SSP,  /* pxa 210, 250, 255, 26x */
@@ -164,6 +172,7 @@ enum pxa_ssp_type {
         PXA168_SSP,
         PXA910_SSP,
         CE4100_SSP,
+        LPSS_SSP,
 };
 
 struct ssp_device {