xref: /linux/drivers/spi/spi-pxa2xx.h (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 
25 struct 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 
93 struct chip_data {
94 	u32 cr0;
95 	u32 cr1;
96 	u32 dds_rate;
97 	u32 psp;
98 	u32 timeout;
99 	u8 n_bytes;
100 	u32 dma_burst_size;
101 	u32 threshold;
102 	u32 dma_threshold;
103 	u16 lpss_rx_threshold;
104 	u16 lpss_tx_threshold;
105 	u8 enable_dma;
106 	u8 bits_per_word;
107 	u32 speed_hz;
108 	union {
109 		int gpio_cs;
110 		unsigned int frm;
111 	};
112 	int gpio_cs_inverted;
113 	int (*write)(struct driver_data *drv_data);
114 	int (*read)(struct driver_data *drv_data);
115 	void (*cs_control)(u32 command);
116 };
117 
118 static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data,
119 				  unsigned reg)
120 {
121 	return __raw_readl(drv_data->ioaddr + reg);
122 }
123 
124 static  inline void pxa2xx_spi_write(const struct driver_data *drv_data,
125 				     unsigned reg, u32 val)
126 {
127 	__raw_writel(val, drv_data->ioaddr + reg);
128 }
129 
130 #define START_STATE ((void *)0)
131 #define RUNNING_STATE ((void *)1)
132 #define DONE_STATE ((void *)2)
133 #define ERROR_STATE ((void *)-1)
134 
135 #define IS_DMA_ALIGNED(x)	IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
136 #define DMA_ALIGNMENT		8
137 
138 static inline int pxa25x_ssp_comp(struct driver_data *drv_data)
139 {
140 	switch (drv_data->ssp_type) {
141 	case PXA25x_SSP:
142 	case CE4100_SSP:
143 	case QUARK_X1000_SSP:
144 		return 1;
145 	default:
146 		return 0;
147 	}
148 }
149 
150 static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
151 {
152 	if (drv_data->ssp_type == CE4100_SSP ||
153 	    drv_data->ssp_type == QUARK_X1000_SSP)
154 		val |= pxa2xx_spi_read(drv_data, SSSR) & SSSR_ALT_FRM_MASK;
155 
156 	pxa2xx_spi_write(drv_data, SSSR, val);
157 }
158 
159 extern int pxa2xx_spi_flush(struct driver_data *drv_data);
160 extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
161 
162 /*
163  * Select the right DMA implementation.
164  */
165 #if defined(CONFIG_SPI_PXA2XX_PXADMA)
166 #define SPI_PXA2XX_USE_DMA	1
167 #define MAX_DMA_LEN		8191
168 #define DEFAULT_DMA_CR1		(SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE)
169 #elif defined(CONFIG_SPI_PXA2XX_DMA)
170 #define SPI_PXA2XX_USE_DMA	1
171 #define MAX_DMA_LEN		SZ_64K
172 #define DEFAULT_DMA_CR1		(SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
173 #else
174 #undef SPI_PXA2XX_USE_DMA
175 #define MAX_DMA_LEN		0
176 #define DEFAULT_DMA_CR1		0
177 #endif
178 
179 #ifdef SPI_PXA2XX_USE_DMA
180 extern bool pxa2xx_spi_dma_is_possible(size_t len);
181 extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
182 extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
183 extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
184 extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
185 extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
186 extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
187 extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data);
188 extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
189 						  struct spi_device *spi,
190 						  u8 bits_per_word,
191 						  u32 *burst_code,
192 						  u32 *threshold);
193 #else
194 static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
195 static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
196 {
197 	return 0;
198 }
199 #define pxa2xx_spi_dma_transfer NULL
200 static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
201 					  u32 dma_burst) {}
202 static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
203 static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
204 {
205 	return 0;
206 }
207 static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
208 static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {}
209 static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
210 							 struct spi_device *spi,
211 							 u8 bits_per_word,
212 							 u32 *burst_code,
213 							 u32 *threshold)
214 {
215 	return -ENODEV;
216 }
217 #endif
218 
219 #endif /* SPI_PXA2XX_H */
220