xref: /linux/drivers/spi/spi-pxa2xx.h (revision 001821b0e79716c4e17c71d8e053a23599a7a508)
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/dmaengine.h>
11 #include <linux/irqreturn.h>
12 #include <linux/types.h>
13 #include <linux/sizes.h>
14 
15 #include <linux/pxa2xx_ssp.h>
16 
17 struct gpio_desc;
18 
19 /*
20  * The platform data for SSP controller devices
21  * (resides in device.platform_data).
22  */
23 struct pxa2xx_spi_controller {
24 	u8 num_chipselect;
25 	u8 enable_dma;
26 	u8 dma_burst_size;
27 	bool is_target;
28 
29 	/* DMA engine specific config */
30 	dma_filter_fn dma_filter;
31 	void *tx_param;
32 	void *rx_param;
33 
34 	/* For non-PXA arches */
35 	struct ssp_device ssp;
36 };
37 
38 struct spi_controller;
39 struct spi_device;
40 struct spi_transfer;
41 
42 struct driver_data {
43 	/* SSP Info */
44 	struct ssp_device *ssp;
45 
46 	/* SPI framework hookup */
47 	enum pxa_ssp_type ssp_type;
48 	struct spi_controller *controller;
49 
50 	/* PXA hookup */
51 	struct pxa2xx_spi_controller *controller_info;
52 
53 	/* SSP masks*/
54 	u32 dma_cr1;
55 	u32 int_cr1;
56 	u32 clear_sr;
57 	u32 mask_sr;
58 
59 	/* DMA engine support */
60 	atomic_t dma_running;
61 
62 	/* Current transfer state info */
63 	void *tx;
64 	void *tx_end;
65 	void *rx;
66 	void *rx_end;
67 	u8 n_bytes;
68 	int (*write)(struct driver_data *drv_data);
69 	int (*read)(struct driver_data *drv_data);
70 	irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
71 
72 	void __iomem *lpss_base;
73 
74 	/* Optional slave FIFO ready signal */
75 	struct gpio_desc *gpiod_ready;
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 
134 #endif /* SPI_PXA2XX_H */
135