xref: /openbmc/linux/drivers/spi/spi-pxa2xx.h (revision 9cfc5c90)
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 	/* SSP register addresses */
40 	void __iomem *ioaddr;
41 	u32 ssdr_physical;
42 
43 	/* SSP masks*/
44 	u32 dma_cr1;
45 	u32 int_cr1;
46 	u32 clear_sr;
47 	u32 mask_sr;
48 
49 	/* Message Transfer pump */
50 	struct tasklet_struct pump_transfers;
51 
52 	/* DMA engine support */
53 	struct dma_chan *rx_chan;
54 	struct dma_chan *tx_chan;
55 	struct sg_table rx_sgt;
56 	struct sg_table tx_sgt;
57 	int rx_nents;
58 	int tx_nents;
59 	void *dummy;
60 	atomic_t dma_running;
61 
62 	/* Current message transfer state info */
63 	struct spi_message *cur_msg;
64 	struct spi_transfer *cur_transfer;
65 	struct chip_data *cur_chip;
66 	size_t len;
67 	void *tx;
68 	void *tx_end;
69 	void *rx;
70 	void *rx_end;
71 	int dma_mapped;
72 	dma_addr_t rx_dma;
73 	dma_addr_t tx_dma;
74 	size_t rx_map_len;
75 	size_t tx_map_len;
76 	u8 n_bytes;
77 	int (*write)(struct driver_data *drv_data);
78 	int (*read)(struct driver_data *drv_data);
79 	irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
80 	void (*cs_control)(u32 command);
81 
82 	void __iomem *lpss_base;
83 };
84 
85 struct chip_data {
86 	u32 cr1;
87 	u32 dds_rate;
88 	u32 timeout;
89 	u8 n_bytes;
90 	u32 dma_burst_size;
91 	u32 threshold;
92 	u32 dma_threshold;
93 	u16 lpss_rx_threshold;
94 	u16 lpss_tx_threshold;
95 	u8 enable_dma;
96 	union {
97 		int gpio_cs;
98 		unsigned int frm;
99 	};
100 	int gpio_cs_inverted;
101 	int (*write)(struct driver_data *drv_data);
102 	int (*read)(struct driver_data *drv_data);
103 	void (*cs_control)(u32 command);
104 };
105 
106 static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data,
107 				  unsigned reg)
108 {
109 	return __raw_readl(drv_data->ioaddr + reg);
110 }
111 
112 static  inline void pxa2xx_spi_write(const struct driver_data *drv_data,
113 				     unsigned reg, u32 val)
114 {
115 	__raw_writel(val, drv_data->ioaddr + reg);
116 }
117 
118 #define START_STATE ((void *)0)
119 #define RUNNING_STATE ((void *)1)
120 #define DONE_STATE ((void *)2)
121 #define ERROR_STATE ((void *)-1)
122 
123 #define IS_DMA_ALIGNED(x)	IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT)
124 #define DMA_ALIGNMENT		8
125 
126 static inline int pxa25x_ssp_comp(struct driver_data *drv_data)
127 {
128 	switch (drv_data->ssp_type) {
129 	case PXA25x_SSP:
130 	case CE4100_SSP:
131 	case QUARK_X1000_SSP:
132 		return 1;
133 	default:
134 		return 0;
135 	}
136 }
137 
138 static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
139 {
140 	if (drv_data->ssp_type == CE4100_SSP ||
141 	    drv_data->ssp_type == QUARK_X1000_SSP)
142 		val |= pxa2xx_spi_read(drv_data, SSSR) & SSSR_ALT_FRM_MASK;
143 
144 	pxa2xx_spi_write(drv_data, SSSR, val);
145 }
146 
147 extern int pxa2xx_spi_flush(struct driver_data *drv_data);
148 extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
149 
150 /*
151  * Select the right DMA implementation.
152  */
153 #if defined(CONFIG_SPI_PXA2XX_DMA)
154 #define SPI_PXA2XX_USE_DMA	1
155 #define MAX_DMA_LEN		SZ_64K
156 #define DEFAULT_DMA_CR1		(SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
157 #else
158 #undef SPI_PXA2XX_USE_DMA
159 #define MAX_DMA_LEN		0
160 #define DEFAULT_DMA_CR1		0
161 #endif
162 
163 #ifdef SPI_PXA2XX_USE_DMA
164 extern bool pxa2xx_spi_dma_is_possible(size_t len);
165 extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
166 extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
167 extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
168 extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
169 extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
170 extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
171 extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
172 						  struct spi_device *spi,
173 						  u8 bits_per_word,
174 						  u32 *burst_code,
175 						  u32 *threshold);
176 #else
177 static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
178 static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
179 {
180 	return 0;
181 }
182 #define pxa2xx_spi_dma_transfer NULL
183 static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
184 					  u32 dma_burst) {}
185 static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
186 static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
187 {
188 	return 0;
189 }
190 static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
191 static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
192 							 struct spi_device *spi,
193 							 u8 bits_per_word,
194 							 u32 *burst_code,
195 							 u32 *threshold)
196 {
197 	return -ENODEV;
198 }
199 #endif
200 
201 #endif /* SPI_PXA2XX_H */
202