spi/pxa2xx: break out the private DMA API usage into a separate file

The PXA SPI driver uses PXA platform specific private DMA implementation
which does not work on non-PXA platforms. In order to use this driver on
other platforms we break out the private DMA implementation into a separate
file that gets compiled only when CONFIG_SPI_PXA2XX_PXADMA is set. The DMA
functions are stubbed out if there is no DMA implementation selected (i.e
we are building on non-PXA platform).

While we are there we can kill the dummy DMA bits in pxa2xx_spi.h as they
are not needed anymore for CE4100.

Once this is done we can add the generic DMA engine support to the driver
that allows usage of any DMA controller that implements DMA engine API.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 185 insertions, 0 deletions

diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h
new file mode 100644
index 000000000000..0a98905c916e
--- /dev/null
+++ b/drivers/spi/spi-pxa2xx.h
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
+ * Copyright (C) 2013, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef SPI_PXA2XX_H
+#define SPI_PXA2XX_H
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pxa2xx_ssp.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/pxa2xx_spi.h>
+
+struct driver_data {
+	/* Driver model hookup */
+	struct platform_device *pdev;
+
+	/* SSP Info */
+	struct ssp_device *ssp;
+
+	/* SPI framework hookup */
+	enum pxa_ssp_type ssp_type;
+	struct spi_master *master;
+
+	/* PXA hookup */
+	struct pxa2xx_spi_master *master_info;
+
+	/* PXA private DMA setup stuff */
+	int rx_channel;
+	int tx_channel;
+	u32 *null_dma_buf;
+
+	/* SSP register addresses */
+	void __iomem *ioaddr;
+	u32 ssdr_physical;
+
+	/* SSP masks*/
+	u32 dma_cr1;
+	u32 int_cr1;
+	u32 clear_sr;
+	u32 mask_sr;
+
+	/* Maximun clock rate */
+	unsigned long max_clk_rate;
+
+	/* Message Transfer pump */
+	struct tasklet_struct pump_transfers;
+
+	/* Current message transfer state info */
+	struct spi_message *cur_msg;
+	struct spi_transfer *cur_transfer;
+	struct chip_data *cur_chip;
+	size_t len;
+	void *tx;
+	void *tx_end;
+	void *rx;
+	void *rx_end;
+	int dma_mapped;
+	dma_addr_t rx_dma;
+	dma_addr_t tx_dma;
+	size_t rx_map_len;
+	size_t tx_map_len;
+	u8 n_bytes;
+	int (*write)(struct driver_data *drv_data);
+	int (*read)(struct driver_data *drv_data);
+	irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
+	void (*cs_control)(u32 command);
+};
+
+struct chip_data {
+	u32 cr0;
+	u32 cr1;
+	u32 psp;
+	u32 timeout;
+	u8 n_bytes;
+	u32 dma_burst_size;
+	u32 threshold;
+	u32 dma_threshold;
+	u8 enable_dma;
+	u8 bits_per_word;
+	u32 speed_hz;
+	union {
+		int gpio_cs;
+		unsigned int frm;
+	};
+	int gpio_cs_inverted;
+	int (*write)(struct driver_data *drv_data);
+	int (*read)(struct driver_data *drv_data);
+	void (*cs_control)(u32 command);
+};
+
+#define DEFINE_SSP_REG(reg, off) \
+static inline u32 read_##reg(void const __iomem *p) \
+{ return __raw_readl(p + (off)); } \
+\
+static inline void write_##reg(u32 v, void __iomem *p) \
+{ __raw_writel(v, p + (off)); }
+
+DEFINE_SSP_REG(SSCR0, 0x00)
+DEFINE_SSP_REG(SSCR1, 0x04)
+DEFINE_SSP_REG(SSSR, 0x08)
+DEFINE_SSP_REG(SSITR, 0x0c)
+DEFINE_SSP_REG(SSDR, 0x10)
+DEFINE_SSP_REG(SSTO, 0x28)
+DEFINE_SSP_REG(SSPSP, 0x2c)
+
+#define START_STATE ((void *)0)
+#define RUNNING_STATE ((void *)1)
+#define DONE_STATE ((void *)2)
+#define ERROR_STATE ((void *)-1)
+
+#define MAX_DMA_LEN		8191
+#define IS_DMA_ALIGNED(x)	IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
+#define DMA_ALIGNMENT		8
+
+static inline int pxa25x_ssp_comp(struct driver_data *drv_data)
+{
+	if (drv_data->ssp_type == PXA25x_SSP)
+		return 1;
+	if (drv_data->ssp_type == CE4100_SSP)
+		return 1;
+	return 0;
+}
+
+static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
+{
+	void __iomem *reg = drv_data->ioaddr;
+
+	if (drv_data->ssp_type == CE4100_SSP)
+		val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK;
+
+	write_SSSR(val, reg);
+}
+
+extern int pxa2xx_spi_flush(struct driver_data *drv_data);
+extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
+
+#if defined(CONFIG_SPI_PXA2XX_PXADMA)
+extern bool pxa2xx_spi_dma_is_possible(size_t len);
+extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
+extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
+extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
+extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
+extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
+extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
+extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data);
+extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+						  struct spi_device *spi,
+						  u8 bits_per_word,
+						  u32 *burst_code,
+						  u32 *threshold);
+#else
+static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
+static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
+{
+	return 0;
+}
+#define pxa2xx_spi_dma_transfer NULL
+static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
+					  u32 dma_burst) {}
+static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
+static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
+{
+	return 0;
+}
+static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
+static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {}
+static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
+							 struct spi_device *spi,
+							 u8 bits_per_word,
+							 u32 *burst_code,
+							 u32 *threshold)
+{
+	return -ENODEV;
+}
+#endif
+
+#endif /* SPI_PXA2XX_H */