1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * MIPI Display Bus Interface (DBI) LCD controller support
4  *
5  * Copyright 2016 Noralf Trønnes
6  */
7 
8 #ifndef __LINUX_MIPI_DBI_H
9 #define __LINUX_MIPI_DBI_H
10 
11 #include <linux/mutex.h>
12 #include <drm/drm_device.h>
13 #include <drm/drm_simple_kms_helper.h>
14 
15 struct drm_rect;
16 struct spi_device;
17 struct gpio_desc;
18 struct regulator;
19 
20 /**
21  * struct mipi_dbi - MIPI DBI interface
22  */
23 struct mipi_dbi {
24 	/**
25 	 * @cmdlock: Command lock
26 	 */
27 	struct mutex cmdlock;
28 
29 	/**
30 	 * @command: Bus specific callback executing commands.
31 	 */
32 	int (*command)(struct mipi_dbi *dbi, u8 *cmd, u8 *param, size_t num);
33 
34 	/**
35 	 * @read_commands: Array of read commands terminated by a zero entry.
36 	 *                 Reading is disabled if this is NULL.
37 	 */
38 	const u8 *read_commands;
39 
40 	/**
41 	 * @swap_bytes: Swap bytes in buffer before transfer
42 	 */
43 	bool swap_bytes;
44 
45 	/**
46 	 * @reset: Optional reset gpio
47 	 */
48 	struct gpio_desc *reset;
49 
50 	/* Type C specific */
51 
52 	/**
53 	 * @spi: SPI device
54 	 */
55 	struct spi_device *spi;
56 
57 	/**
58 	 * @dc: Optional D/C gpio.
59 	 */
60 	struct gpio_desc *dc;
61 
62 	/**
63 	 * @tx_buf9: Buffer used for Option 1 9-bit conversion
64 	 */
65 	void *tx_buf9;
66 
67 	/**
68 	 * @tx_buf9_len: Size of tx_buf9.
69 	 */
70 	size_t tx_buf9_len;
71 };
72 
73 /**
74  * struct mipi_dbi_dev - MIPI DBI device
75  */
76 struct mipi_dbi_dev {
77 	/**
78 	 * @drm: DRM device
79 	 */
80 	struct drm_device drm;
81 
82 	/**
83 	 * @pipe: Display pipe structure
84 	 */
85 	struct drm_simple_display_pipe pipe;
86 
87 	/**
88 	 * @connector: Connector
89 	 */
90 	struct drm_connector connector;
91 
92 	/**
93 	 * @mode: Fixed display mode
94 	 */
95 	struct drm_display_mode mode;
96 
97 	/**
98 	 * @tx_buf: Buffer used for transfer (copy clip rect area)
99 	 */
100 	u16 *tx_buf;
101 
102 	/**
103 	 * @rotation: initial rotation in degrees Counter Clock Wise
104 	 */
105 	unsigned int rotation;
106 
107 	/**
108 	 * @left_offset: Horizontal offset of the display relative to the
109 	 *               controller's driver array
110 	 */
111 	unsigned int left_offset;
112 
113 	/**
114 	 * @top_offset: Vertical offset of the display relative to the
115 	 *              controller's driver array
116 	 */
117 	unsigned int top_offset;
118 
119 	/**
120 	 * @backlight: backlight device (optional)
121 	 */
122 	struct backlight_device *backlight;
123 
124 	/**
125 	 * @regulator: power regulator (optional)
126 	 */
127 	struct regulator *regulator;
128 
129 	/**
130 	 * @dbi: MIPI DBI interface
131 	 */
132 	struct mipi_dbi dbi;
133 };
134 
drm_to_mipi_dbi_dev(struct drm_device * drm)135 static inline struct mipi_dbi_dev *drm_to_mipi_dbi_dev(struct drm_device *drm)
136 {
137 	return container_of(drm, struct mipi_dbi_dev, drm);
138 }
139 
140 int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *dbi,
141 		      struct gpio_desc *dc);
142 int mipi_dbi_dev_init_with_formats(struct mipi_dbi_dev *dbidev,
143 				   const struct drm_simple_display_pipe_funcs *funcs,
144 				   const uint32_t *formats, unsigned int format_count,
145 				   const struct drm_display_mode *mode,
146 				   unsigned int rotation, size_t tx_buf_size);
147 int mipi_dbi_dev_init(struct mipi_dbi_dev *dbidev,
148 		      const struct drm_simple_display_pipe_funcs *funcs,
149 		      const struct drm_display_mode *mode, unsigned int rotation);
150 void mipi_dbi_pipe_update(struct drm_simple_display_pipe *pipe,
151 			  struct drm_plane_state *old_state);
152 void mipi_dbi_enable_flush(struct mipi_dbi_dev *dbidev,
153 			   struct drm_crtc_state *crtc_state,
154 			   struct drm_plane_state *plan_state);
155 void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe);
156 void mipi_dbi_hw_reset(struct mipi_dbi *dbi);
157 bool mipi_dbi_display_is_on(struct mipi_dbi *dbi);
158 int mipi_dbi_poweron_reset(struct mipi_dbi_dev *dbidev);
159 int mipi_dbi_poweron_conditional_reset(struct mipi_dbi_dev *dbidev);
160 
161 u32 mipi_dbi_spi_cmd_max_speed(struct spi_device *spi, size_t len);
162 int mipi_dbi_spi_transfer(struct spi_device *spi, u32 speed_hz,
163 			  u8 bpw, const void *buf, size_t len);
164 
165 int mipi_dbi_command_read(struct mipi_dbi *dbi, u8 cmd, u8 *val);
166 int mipi_dbi_command_buf(struct mipi_dbi *dbi, u8 cmd, u8 *data, size_t len);
167 int mipi_dbi_command_stackbuf(struct mipi_dbi *dbi, u8 cmd, const u8 *data,
168 			      size_t len);
169 int mipi_dbi_buf_copy(void *dst, struct drm_framebuffer *fb,
170 		      struct drm_rect *clip, bool swap);
171 /**
172  * mipi_dbi_command - MIPI DCS command with optional parameter(s)
173  * @dbi: MIPI DBI structure
174  * @cmd: Command
175  * @seq: Optional parameter(s)
176  *
177  * Send MIPI DCS command to the controller. Use mipi_dbi_command_read() for
178  * get/read.
179  *
180  * Returns:
181  * Zero on success, negative error code on failure.
182  */
183 #define mipi_dbi_command(dbi, cmd, seq...) \
184 ({ \
185 	const u8 d[] = { seq }; \
186 	struct device *dev = &(dbi)->spi->dev;	\
187 	int ret; \
188 	ret = mipi_dbi_command_stackbuf(dbi, cmd, d, ARRAY_SIZE(d)); \
189 	if (ret) \
190 		dev_err_ratelimited(dev, "error %d when sending command %#02x\n", ret, cmd); \
191 	ret; \
192 })
193 
194 #ifdef CONFIG_DEBUG_FS
195 void mipi_dbi_debugfs_init(struct drm_minor *minor);
196 #else
197 #define mipi_dbi_debugfs_init		NULL
198 #endif
199 
200 #endif /* __LINUX_MIPI_DBI_H */
201