davidlt/kernel-ark
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
b943949105
kernel-ark/drivers/spi/spi-pxa2xx.h
Mika Westerberg a0d2642e92 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>
2013-02-08 13:14:40 +00:00

222 lines
5.6 KiB
C
Raw Blame History

/*
* 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/atomic.h>
#include <linux/dmaengine.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/scatterlist.h>
#include <linux/sizes.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;
/* DMA engine support */
struct dma_chan *rx_chan;
struct dma_chan *tx_chan;
struct sg_table rx_sgt;
struct sg_table tx_sgt;
int rx_nents;
int tx_nents;
void *dummy;
atomic_t dma_running;
/* 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);
void __iomem *lpss_base;
};
struct chip_data {
u32 cr0;
u32 cr1;
u32 psp;
u32 timeout;
u8 n_bytes;
u32 dma_burst_size;
u32 threshold;
u32 dma_threshold;
u16 lpss_rx_threshold;
u16 lpss_tx_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_SSP_REG(SSITF, SSITF)
DEFINE_SSP_REG(SSIRF, SSIRF)
#define START_STATE ((void *)0)
#define RUNNING_STATE ((void *)1)
#define DONE_STATE ((void *)2)
#define ERROR_STATE ((void *)-1)
#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);
/*
* Select the right DMA implementation.
*/
#if defined(CONFIG_SPI_PXA2XX_PXADMA)
#define SPI_PXA2XX_USE_DMA 1
#define MAX_DMA_LEN 8191
#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE)
#elif defined(CONFIG_SPI_PXA2XX_DMA)
#define SPI_PXA2XX_USE_DMA 1
#define MAX_DMA_LEN SZ_64K
#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
#else
#undef SPI_PXA2XX_USE_DMA
#define MAX_DMA_LEN 0
#define DEFAULT_DMA_CR1 0
#endif
#ifdef SPI_PXA2XX_USE_DMA
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 */
Reference in New Issue View Git Blame Copy Permalink