xref: /openbmc/linux/drivers/spi/spi-pxa2xx.h (revision f3956ebb)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
4  * Copyright (C) 2013, 2021 Intel Corporation
5  */
6 
7 #ifndef SPI_PXA2XX_H
8 #define SPI_PXA2XX_H
9 
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/types.h>
13 #include <linux/sizes.h>
14 
15 #include <linux/pxa2xx_ssp.h>
16 
17 struct gpio_desc;
18 struct pxa2xx_spi_controller;
19 struct spi_controller;
20 struct spi_device;
21 struct spi_transfer;
22 
23 struct driver_data {
24 	/* SSP Info */
25 	struct ssp_device *ssp;
26 
27 	/* SPI framework hookup */
28 	enum pxa_ssp_type ssp_type;
29 	struct spi_controller *controller;
30 
31 	/* PXA hookup */
32 	struct pxa2xx_spi_controller *controller_info;
33 
34 	/* SSP masks*/
35 	u32 dma_cr1;
36 	u32 int_cr1;
37 	u32 clear_sr;
38 	u32 mask_sr;
39 
40 	/* DMA engine support */
41 	atomic_t dma_running;
42 
43 	/* Current transfer state info */
44 	void *tx;
45 	void *tx_end;
46 	void *rx;
47 	void *rx_end;
48 	u8 n_bytes;
49 	int (*write)(struct driver_data *drv_data);
50 	int (*read)(struct driver_data *drv_data);
51 	irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
52 	void (*cs_control)(u32 command);
53 
54 	void __iomem *lpss_base;
55 
56 	/* Optional slave FIFO ready signal */
57 	struct gpio_desc *gpiod_ready;
58 };
59 
60 struct chip_data {
61 	u32 cr1;
62 	u32 dds_rate;
63 	u32 timeout;
64 	u8 n_bytes;
65 	u8 enable_dma;
66 	u32 dma_burst_size;
67 	u32 dma_threshold;
68 	u32 threshold;
69 	u16 lpss_rx_threshold;
70 	u16 lpss_tx_threshold;
71 
72 	int (*write)(struct driver_data *drv_data);
73 	int (*read)(struct driver_data *drv_data);
74 
75 	void (*cs_control)(u32 command);
76 };
77 
78 static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data, u32 reg)
79 {
80 	return pxa_ssp_read_reg(drv_data->ssp, reg);
81 }
82 
83 static inline void pxa2xx_spi_write(const struct driver_data *drv_data, u32 reg, u32 val)
84 {
85 	pxa_ssp_write_reg(drv_data->ssp, reg, val);
86 }
87 
88 #define DMA_ALIGNMENT		8
89 
90 static inline int pxa25x_ssp_comp(const struct driver_data *drv_data)
91 {
92 	switch (drv_data->ssp_type) {
93 	case PXA25x_SSP:
94 	case CE4100_SSP:
95 	case QUARK_X1000_SSP:
96 		return 1;
97 	default:
98 		return 0;
99 	}
100 }
101 
102 static inline void clear_SSCR1_bits(const struct driver_data *drv_data, u32 bits)
103 {
104 	pxa2xx_spi_write(drv_data, SSCR1, pxa2xx_spi_read(drv_data, SSCR1) & ~bits);
105 }
106 
107 static inline u32 read_SSSR_bits(const struct driver_data *drv_data, u32 bits)
108 {
109 	return pxa2xx_spi_read(drv_data, SSSR) & bits;
110 }
111 
112 static inline void write_SSSR_CS(const struct driver_data *drv_data, u32 val)
113 {
114 	if (drv_data->ssp_type == CE4100_SSP ||
115 	    drv_data->ssp_type == QUARK_X1000_SSP)
116 		val |= read_SSSR_bits(drv_data, SSSR_ALT_FRM_MASK);
117 
118 	pxa2xx_spi_write(drv_data, SSSR, val);
119 }
120 
121 extern int pxa2xx_spi_flush(struct driver_data *drv_data);
122 
123 #define MAX_DMA_LEN		SZ_64K
124 #define DEFAULT_DMA_CR1		(SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
125 
126 extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
127 extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
128 				  struct spi_transfer *xfer);
129 extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
130 extern void pxa2xx_spi_dma_stop(struct driver_data *drv_data);
131 extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
132 extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
133 extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
134 						  struct spi_device *spi,
135 						  u8 bits_per_word,
136 						  u32 *burst_code,
137 						  u32 *threshold);
138 
139 #endif /* SPI_PXA2XX_H */
140