xref: /openbmc/linux/drivers/spi/spi-pxa2xx.h (revision 37002bc6)
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 
53 	void __iomem *lpss_base;
54 
55 	/* Optional slave FIFO ready signal */
56 	struct gpio_desc *gpiod_ready;
57 };
58 
59 struct chip_data {
60 	u32 cr1;
61 	u32 dds_rate;
62 	u32 timeout;
63 	u8 enable_dma;
64 	u32 dma_burst_size;
65 	u32 dma_threshold;
66 	u32 threshold;
67 	u16 lpss_rx_threshold;
68 	u16 lpss_tx_threshold;
69 };
70 
71 static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data, u32 reg)
72 {
73 	return pxa_ssp_read_reg(drv_data->ssp, reg);
74 }
75 
76 static inline void pxa2xx_spi_write(const struct driver_data *drv_data, u32 reg, u32 val)
77 {
78 	pxa_ssp_write_reg(drv_data->ssp, reg, val);
79 }
80 
81 #define DMA_ALIGNMENT		8
82 
83 static inline int pxa25x_ssp_comp(const struct driver_data *drv_data)
84 {
85 	switch (drv_data->ssp_type) {
86 	case PXA25x_SSP:
87 	case CE4100_SSP:
88 	case QUARK_X1000_SSP:
89 		return 1;
90 	default:
91 		return 0;
92 	}
93 }
94 
95 static inline void clear_SSCR1_bits(const struct driver_data *drv_data, u32 bits)
96 {
97 	pxa2xx_spi_write(drv_data, SSCR1, pxa2xx_spi_read(drv_data, SSCR1) & ~bits);
98 }
99 
100 static inline u32 read_SSSR_bits(const struct driver_data *drv_data, u32 bits)
101 {
102 	return pxa2xx_spi_read(drv_data, SSSR) & bits;
103 }
104 
105 static inline void write_SSSR_CS(const struct driver_data *drv_data, u32 val)
106 {
107 	if (drv_data->ssp_type == CE4100_SSP ||
108 	    drv_data->ssp_type == QUARK_X1000_SSP)
109 		val |= read_SSSR_bits(drv_data, SSSR_ALT_FRM_MASK);
110 
111 	pxa2xx_spi_write(drv_data, SSSR, val);
112 }
113 
114 extern int pxa2xx_spi_flush(struct driver_data *drv_data);
115 
116 #define MAX_DMA_LEN		SZ_64K
117 #define DEFAULT_DMA_CR1		(SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
118 
119 extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
120 extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
121 				  struct spi_transfer *xfer);
122 extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
123 extern void pxa2xx_spi_dma_stop(struct driver_data *drv_data);
124 extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
125 extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
126 extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
127 						  struct spi_device *spi,
128 						  u8 bits_per_word,
129 						  u32 *burst_code,
130 						  u32 *threshold);
131 
132 #endif /* SPI_PXA2XX_H */
133