tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 */