spi/dw_spi: add DMA support

dw_spi driver in upstream only supports PIO mode, and this patch
will support it to cowork with the Designware dma controller used
on Intel Moorestown platform, at the same time it provides a general
framework to support dw_spi core to cowork with dma controllers on
other platforms

It has been tested with a Option GTM501L 3G modem and Infenion 60x60
modem. To use DMA mode, DMA controller 2 of Moorestown has to be enabled

Also change the dma interface suggested by Linus Walleij.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
[Typo fix and renames to match intel_mid_dma renaming]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 19 insertions, 5 deletions

diff --git a/include/linux/spi/dw_spi.h b/include/linux/spi/dw_spi.h
index c91302f3a257..6cd10f6ad472 100644
--- a/include/linux/spi/dw_spi.h
+++ b/include/linux/spi/dw_spi.h
@@ -1,5 +1,6 @@
 #ifndef DW_SPI_HEADER_H
 #define DW_SPI_HEADER_H
+
 #include <linux/io.h>
 
 /* Bit fields in CTRLR0 */
@@ -82,6 +83,13 @@ struct dw_spi_reg {
                                 though only low 16 bits matters */
 } __packed;
 
+struct dw_spi;
+struct dw_spi_dma_ops {
+        int (*dma_init)(struct dw_spi *dws);
+        void (*dma_exit)(struct dw_spi *dws);
+        int (*dma_transfer)(struct dw_spi *dws, int cs_change);
+};
+
 struct dw_spi {
         struct spi_master       *master;
         struct spi_device       *cur_dev;
@@ -136,13 +144,15 @@ struct dw_spi {
         /* Dma info */
         int                     dma_inited;
         struct dma_chan         *txchan;
+        struct scatterlist      tx_sgl;
         struct dma_chan         *rxchan;
-        int                     txdma_done;
-        int                     rxdma_done;
-        u64                     tx_param;
-        u64                     rx_param;
+        struct scatterlist      rx_sgl;
+        int                     dma_chan_done;
         struct device           *dma_dev;
-        dma_addr_t              dma_addr;
+        dma_addr_t              dma_addr; /* phy address of the Data register */
+        struct dw_spi_dma_ops   *dma_ops;
+        void                    *dma_priv; /* platform relate info */
+        struct pci_dev          *dmac;
 
         /* Bus interface info */
         void                    *priv;
@@ -216,4 +226,8 @@ extern int dw_spi_add_host(struct dw_spi *dws);
 extern void dw_spi_remove_host(struct dw_spi *dws);
 extern int dw_spi_suspend_host(struct dw_spi *dws);
 extern int dw_spi_resume_host(struct dw_spi *dws);
+extern void dw_spi_xfer_done(struct dw_spi *dws);
+
+/* platform related setup */
+extern int dw_spi_mid_init(struct dw_spi *dws); /* Intel MID platforms */
 #endif /* DW_SPI_HEADER_H */