linux/drivers/spi/spi-pxa2xx.h
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   1/*
   2 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
   3 * Copyright (C) 2013, Intel Corporation
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 */
   9
  10#ifndef SPI_PXA2XX_H
  11#define SPI_PXA2XX_H
  12
  13#include <linux/atomic.h>
  14#include <linux/dmaengine.h>
  15#include <linux/errno.h>
  16#include <linux/io.h>
  17#include <linux/interrupt.h>
  18#include <linux/platform_device.h>
  19#include <linux/pxa2xx_ssp.h>
  20#include <linux/scatterlist.h>
  21#include <linux/sizes.h>
  22#include <linux/spi/spi.h>
  23#include <linux/spi/pxa2xx_spi.h>
  24
  25struct driver_data {
  26        /* Driver model hookup */
  27        struct platform_device *pdev;
  28
  29        /* SSP Info */
  30        struct ssp_device *ssp;
  31
  32        /* SPI framework hookup */
  33        enum pxa_ssp_type ssp_type;
  34        struct spi_master *master;
  35
  36        /* PXA hookup */
  37        struct pxa2xx_spi_master *master_info;
  38
  39        /* PXA private DMA setup stuff */
  40        int rx_channel;
  41        int tx_channel;
  42        u32 *null_dma_buf;
  43
  44        /* SSP register addresses */
  45        void __iomem *ioaddr;
  46        u32 ssdr_physical;
  47
  48        /* SSP masks*/
  49        u32 dma_cr1;
  50        u32 int_cr1;
  51        u32 clear_sr;
  52        u32 mask_sr;
  53
  54        /* Maximun clock rate */
  55        unsigned long max_clk_rate;
  56
  57        /* Message Transfer pump */
  58        struct tasklet_struct pump_transfers;
  59
  60        /* DMA engine support */
  61        struct dma_chan *rx_chan;
  62        struct dma_chan *tx_chan;
  63        struct sg_table rx_sgt;
  64        struct sg_table tx_sgt;
  65        int rx_nents;
  66        int tx_nents;
  67        void *dummy;
  68        atomic_t dma_running;
  69
  70        /* Current message transfer state info */
  71        struct spi_message *cur_msg;
  72        struct spi_transfer *cur_transfer;
  73        struct chip_data *cur_chip;
  74        size_t len;
  75        void *tx;
  76        void *tx_end;
  77        void *rx;
  78        void *rx_end;
  79        int dma_mapped;
  80        dma_addr_t rx_dma;
  81        dma_addr_t tx_dma;
  82        size_t rx_map_len;
  83        size_t tx_map_len;
  84        u8 n_bytes;
  85        int (*write)(struct driver_data *drv_data);
  86        int (*read)(struct driver_data *drv_data);
  87        irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
  88        void (*cs_control)(u32 command);
  89
  90        void __iomem *lpss_base;
  91};
  92
  93struct chip_data {
  94        u32 cr0;
  95        u32 cr1;
  96        u32 psp;
  97        u32 timeout;
  98        u8 n_bytes;
  99        u32 dma_burst_size;
 100        u32 threshold;
 101        u32 dma_threshold;
 102        u16 lpss_rx_threshold;
 103        u16 lpss_tx_threshold;
 104        u8 enable_dma;
 105        u8 bits_per_word;
 106        u32 speed_hz;
 107        union {
 108                int gpio_cs;
 109                unsigned int frm;
 110        };
 111        int gpio_cs_inverted;
 112        int (*write)(struct driver_data *drv_data);
 113        int (*read)(struct driver_data *drv_data);
 114        void (*cs_control)(u32 command);
 115};
 116
 117#define DEFINE_SSP_REG(reg, off) \
 118static inline u32 read_##reg(void const __iomem *p) \
 119{ return __raw_readl(p + (off)); } \
 120\
 121static inline void write_##reg(u32 v, void __iomem *p) \
 122{ __raw_writel(v, p + (off)); }
 123
 124DEFINE_SSP_REG(SSCR0, 0x00)
 125DEFINE_SSP_REG(SSCR1, 0x04)
 126DEFINE_SSP_REG(SSSR, 0x08)
 127DEFINE_SSP_REG(SSITR, 0x0c)
 128DEFINE_SSP_REG(SSDR, 0x10)
 129DEFINE_SSP_REG(SSTO, 0x28)
 130DEFINE_SSP_REG(SSPSP, 0x2c)
 131DEFINE_SSP_REG(SSITF, SSITF)
 132DEFINE_SSP_REG(SSIRF, SSIRF)
 133
 134#define START_STATE ((void *)0)
 135#define RUNNING_STATE ((void *)1)
 136#define DONE_STATE ((void *)2)
 137#define ERROR_STATE ((void *)-1)
 138
 139#define IS_DMA_ALIGNED(x)       IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
 140#define DMA_ALIGNMENT           8
 141
 142static inline int pxa25x_ssp_comp(struct driver_data *drv_data)
 143{
 144        if (drv_data->ssp_type == PXA25x_SSP)
 145                return 1;
 146        if (drv_data->ssp_type == CE4100_SSP)
 147                return 1;
 148        return 0;
 149}
 150
 151static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
 152{
 153        void __iomem *reg = drv_data->ioaddr;
 154
 155        if (drv_data->ssp_type == CE4100_SSP)
 156                val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK;
 157
 158        write_SSSR(val, reg);
 159}
 160
 161extern int pxa2xx_spi_flush(struct driver_data *drv_data);
 162extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
 163
 164/*
 165 * Select the right DMA implementation.
 166 */
 167#if defined(CONFIG_SPI_PXA2XX_PXADMA)
 168#define SPI_PXA2XX_USE_DMA      1
 169#define MAX_DMA_LEN             8191
 170#define DEFAULT_DMA_CR1         (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE)
 171#elif defined(CONFIG_SPI_PXA2XX_DMA)
 172#define SPI_PXA2XX_USE_DMA      1
 173#define MAX_DMA_LEN             SZ_64K
 174#define DEFAULT_DMA_CR1         (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
 175#else
 176#undef SPI_PXA2XX_USE_DMA
 177#define MAX_DMA_LEN             0
 178#define DEFAULT_DMA_CR1         0
 179#endif
 180
 181#ifdef SPI_PXA2XX_USE_DMA
 182extern bool pxa2xx_spi_dma_is_possible(size_t len);
 183extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
 184extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
 185extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
 186extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
 187extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
 188extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
 189extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data);
 190extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
 191                                                  struct spi_device *spi,
 192                                                  u8 bits_per_word,
 193                                                  u32 *burst_code,
 194                                                  u32 *threshold);
 195#else
 196static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
 197static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
 198{
 199        return 0;
 200}
 201#define pxa2xx_spi_dma_transfer NULL
 202static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
 203                                          u32 dma_burst) {}
 204static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
 205static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
 206{
 207        return 0;
 208}
 209static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
 210static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {}
 211static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
 212                                                         struct spi_device *spi,
 213                                                         u8 bits_per_word,
 214                                                         u32 *burst_code,
 215                                                         u32 *threshold)
 216{
 217        return -ENODEV;
 218}
 219#endif
 220
 221#endif /* SPI_PXA2XX_H */
 222