xref: /netbsd-src/sys/dev/i2c/ssdfb_i2c.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /* $NetBSD: ssdfb_i2c.c,v 1.5 2019/11/05 19:59:35 tnn Exp $ */
2 
3 /*
4  * Copyright (c) 2019 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Tobias Nygren.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: ssdfb_i2c.c,v 1.5 2019/11/05 19:59:35 tnn Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/device.h>
37 #include <dev/wscons/wsdisplayvar.h>
38 #include <dev/rasops/rasops.h>
39 #include <dev/i2c/i2cvar.h>
40 #include <dev/ic/ssdfbvar.h>
41 
42 struct ssdfb_i2c_softc {
43 	struct		ssdfb_softc sc;
44 	i2c_tag_t	sc_i2c_tag;
45 	i2c_addr_t	sc_i2c_addr;
46 	size_t		sc_transfer_size;
47 };
48 
49 static int	ssdfb_i2c_match(device_t, cfdata_t, void *);
50 static void	ssdfb_i2c_attach(device_t, device_t, void *);
51 static int	ssdfb_i2c_detach(device_t, int);
52 
53 static int	ssdfb_i2c_probe_transfer_size(struct ssdfb_i2c_softc *, bool);
54 static int	ssdfb_i2c_transfer(struct ssdfb_i2c_softc *, uint8_t, uint8_t *,
55 				size_t, int);
56 static int	ssdfb_i2c_cmd(void *, uint8_t *, size_t, bool);
57 static int	ssdfb_i2c_transfer_rect(void *, uint8_t, uint8_t, uint8_t,
58 				uint8_t, uint8_t *, size_t, bool);
59 static int	ssdfb_i2c_transfer_rect_ssd1306(void *, uint8_t, uint8_t,
60 				uint8_t, uint8_t, uint8_t *, size_t, bool);
61 static int	ssdfb_i2c_transfer_rect_sh1106(void *, uint8_t, uint8_t,
62 				uint8_t, uint8_t, uint8_t *, size_t, bool);
63 static int	ssdfb_smbus_transfer_rect(void *, uint8_t, uint8_t, uint8_t,
64 				uint8_t, uint8_t *, size_t, bool);
65 
66 CFATTACH_DECL_NEW(ssdfb_iic, sizeof(struct ssdfb_i2c_softc),
67     ssdfb_i2c_match, ssdfb_i2c_attach, ssdfb_i2c_detach, NULL);
68 
69 static const struct device_compatible_entry compat_data[] = {
70 	{ "solomon,ssd1306fb-i2c",	0 },
71 	{ "sino,sh1106fb-i2c",		0 },
72 	{ NULL,				0 }
73 };
74 
75 static int
76 ssdfb_i2c_match(device_t parent, cfdata_t match, void *aux)
77 {
78 	struct i2c_attach_args *ia = aux;
79 	int match_result;
80 
81 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
82 		return match_result;
83 
84 	switch (ia->ia_addr) {
85 	case SSDFB_I2C_DEFAULT_ADDR:
86 	case SSDFB_I2C_ALTERNATIVE_ADDR:
87 		return I2C_MATCH_ADDRESS_ONLY;
88 	}
89 
90 	return 0;
91 }
92 
93 static void
94 ssdfb_i2c_attach(device_t parent, device_t self, void *aux)
95 {
96 	struct ssdfb_i2c_softc *sc = device_private(self);
97 	struct cfdata *cf = device_cfdata(self);
98 	struct i2c_attach_args *ia = aux;
99 	int flags = cf->cf_flags;
100 	int i;
101 
102 	if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN) {
103 		for (i = 0; i < ia->ia_ncompat; i++) {
104 			if (strncmp("solomon,ssd1306", ia->ia_compat[i], 15)
105 			    == 0) {
106 				flags |= SSDFB_PRODUCT_SSD1306_GENERIC;
107 				break;
108 			}
109 			else if (strncmp("sino,sh1106", ia->ia_compat[i], 11)
110 			    == 0) {
111 				flags |= SSDFB_PRODUCT_SH1106_GENERIC;
112 				break;
113 			}
114 		}
115 	}
116 	if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN)
117 		flags |= SSDFB_PRODUCT_SSD1306_GENERIC;
118 
119 	flags |= SSDFB_ATTACH_FLAG_MPSAFE;
120 	sc->sc.sc_dev = self;
121 	sc->sc_i2c_tag = ia->ia_tag;
122 	sc->sc_i2c_addr = ia->ia_addr;
123 	sc->sc.sc_cookie = (void *)sc;
124 	sc->sc.sc_cmd = ssdfb_i2c_cmd;
125 	sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect;
126 
127 	ssdfb_attach(&sc->sc, flags);
128 }
129 
130 static int
131 ssdfb_i2c_detach(device_t self, int flags)
132 {
133 	struct ssdfb_i2c_softc *sc = device_private(self);
134 
135 	return ssdfb_detach(&sc->sc);
136 }
137 
138 static int
139 ssdfb_i2c_probe_transfer_size(struct ssdfb_i2c_softc *sc, bool usepoll)
140 {
141 	int flags = usepoll ? I2C_F_POLL : 0;
142 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
143 	int error;
144 	uint8_t buf[128];
145 	size_t len;
146 
147 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
148 	if (error)
149 		return error;
150 	len = sizeof(buf);
151 	memset(buf, 0, len);
152 	while (len > 0) {
153 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
154 		    sc->sc_i2c_addr, &cb, sizeof(cb), buf, len, flags);
155 		if (!error) {
156 			break;
157 		}
158 		len >>= 1;
159 	}
160 	if (!error && len < 2) {
161 		error = E2BIG;
162 	} else {
163 		sc->sc_transfer_size = len;
164 	}
165 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
166 
167 	return error;
168 }
169 
170 static int
171 ssdfb_i2c_transfer(struct ssdfb_i2c_softc *sc, uint8_t cb, uint8_t *data,
172 		   size_t len, int flags)
173 {
174 	int error;
175 	size_t xfer_size = sc->sc_transfer_size;
176 
177 	while (len >= xfer_size) {
178 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
179 		    sc->sc_i2c_addr, &cb, sizeof(cb), data, xfer_size, flags);
180 		if (error)
181 			return error;
182 		len -= xfer_size;
183 		data += xfer_size;
184 	}
185 	if (len > 0) {
186 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
187 		    sc->sc_i2c_addr, &cb, sizeof(cb), data, len, flags);
188 	}
189 
190 	return error;
191 }
192 
193 static int
194 ssdfb_i2c_cmd(void *cookie, uint8_t *cmd, size_t len, bool usepoll)
195 {
196 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
197 	int flags = usepoll ? I2C_F_POLL : 0;
198 	uint8_t cb = 0;
199 	int error;
200 
201 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
202 	if (error)
203 		return error;
204 	error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
205 	    sc->sc_i2c_addr, &cb, sizeof(cb), cmd, len, flags);
206 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
207 
208 	return error;
209 }
210 
211 static int
212 ssdfb_i2c_transfer_rect(void *cookie, uint8_t fromcol, uint8_t tocol,
213     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
214 {
215 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
216 	uint8_t cmd[2];
217 	int error;
218 
219 	/*
220 	 * Test if large transfers are supported by the parent i2c bus and
221 	 * pick the fastest transfer routine for subsequent invocations.
222 	 */
223 	switch (sc->sc.sc_p->p_controller_id) {
224 	case SSDFB_CONTROLLER_SSD1306:
225 		sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect_ssd1306;
226 		break;
227 	case SSDFB_CONTROLLER_SH1106:
228 		sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect_sh1106;
229 		break;
230 	default:
231 		sc->sc.sc_transfer_rect = ssdfb_smbus_transfer_rect;
232 		break;
233 	}
234 
235 	if (sc->sc.sc_transfer_rect != ssdfb_smbus_transfer_rect) {
236 		error = ssdfb_i2c_probe_transfer_size(sc, usepoll);
237 		if (error)
238 			return error;
239 		aprint_verbose_dev(sc->sc.sc_dev, "%zd-byte transfers\n",
240 		    sc->sc_transfer_size);
241 		if (sc->sc_transfer_size == 2) {
242 			sc->sc.sc_transfer_rect = ssdfb_smbus_transfer_rect;
243 		}
244 	}
245 
246 	/*
247 	 * Set addressing mode for SSD1306.
248 	 */
249 	if (sc->sc.sc_p->p_controller_id == SSDFB_CONTROLLER_SSD1306) {
250 		cmd[0] = SSD1306_CMD_SET_MEMORY_ADDRESSING_MODE;
251 		cmd[1] = sc->sc.sc_transfer_rect
252 		    == ssdfb_i2c_transfer_rect_ssd1306
253 		    ? SSD1306_MEMORY_ADDRESSING_MODE_HORIZONTAL
254 		    : SSD1306_MEMORY_ADDRESSING_MODE_PAGE;
255 		error = ssdfb_i2c_cmd(cookie, cmd, sizeof(cmd), usepoll);
256 		if (error)
257 			return error;
258 	}
259 
260 	return sc->sc.sc_transfer_rect(cookie, fromcol, tocol, frompage, topage,
261 	    p, stride, usepoll);
262 }
263 
264 
265 static int
266 ssdfb_i2c_transfer_rect_ssd1306(void *cookie, uint8_t fromcol, uint8_t tocol,
267     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
268 {
269 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
270 	int flags = usepoll ? I2C_F_POLL : 0;
271 	uint8_t cc = 0;
272 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
273 	size_t len = tocol + 1 - fromcol;
274 	int error;
275 	/*
276 	 * SSD1306 does not implement the Continuation bit correctly.
277 	 * The SH1106 protocol defines that a control byte WITH Co
278 	 * set must be inserted between each command. But SSD1306
279 	 * fails to parse the commands if we do that.
280 	 */
281 	uint8_t cmds[] = {
282 		SSD1306_CMD_SET_COLUMN_ADDRESS,
283 		fromcol, tocol,
284 		SSD1306_CMD_SET_PAGE_ADDRESS,
285 		frompage, topage
286 	};
287 
288 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
289 	if (error)
290 		return error;
291 	error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
292 	    sc->sc_i2c_addr, &cc, sizeof(cc), cmds, sizeof(cmds), flags);
293 	if (error)
294 		goto out;
295 	while (frompage <= topage) {
296 		error = ssdfb_i2c_transfer(sc, cb, p, len, flags);
297 		if (error)
298 			goto out;
299 		frompage++;
300 		p += stride;
301 	}
302 out:
303 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
304 
305 	return error;
306 }
307 
308 static int
309 ssdfb_i2c_transfer_rect_sh1106(void *cookie, uint8_t fromcol, uint8_t tocol,
310     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
311 {
312 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
313 	int flags = usepoll ? I2C_F_POLL : 0;
314 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
315 	uint8_t cc = SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK;
316 	size_t len = tocol + 1 - fromcol;
317 	int error;
318 	uint8_t cmds[] = {
319 		SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage,
320 		SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK,
321 		SSDFB_CMD_SET_HIGHER_COLUMN_START_ADDRESS_BASE + (fromcol >> 4),
322 		SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK,
323 		SSDFB_CMD_SET_LOWER_COLUMN_START_ADDRESS_BASE + (fromcol & 0xf)
324 	};
325 
326 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
327 	if (error)
328 		return error;
329 	while (frompage <= topage) {
330 		cmds[0] = SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage;
331 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
332 		    sc->sc_i2c_addr, &cc, sizeof(cc), cmds, sizeof(cmds), flags);
333 		if (error)
334 			goto out;
335 		error = ssdfb_i2c_transfer(sc, cb, p, len, flags);
336 		if (error)
337 			goto out;
338 		frompage++;
339 		p += stride;
340 	}
341 out:
342 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
343 
344 	return error;
345 }
346 
347 /*
348  * If the parent is an SMBus, then we can only send 2 bytes
349  * of payload per txn. The SSD1306 triple byte commands are
350  * not available so we have to use PAGE addressing mode
351  * and split data into multiple txns.
352  * This is ugly and slow but it's the best we can do.
353  */
354 static int
355 ssdfb_smbus_transfer_rect(void *cookie, uint8_t fromcol, uint8_t tocol,
356     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
357 {
358 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
359 	int flags = usepoll ? I2C_F_POLL : 0;
360 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
361 	uint8_t cc = 0;
362 	size_t len = tocol + 1 - fromcol;
363 	uint8_t cmd_higher_col =
364 	    SSDFB_CMD_SET_HIGHER_COLUMN_START_ADDRESS_BASE + (fromcol >> 4);
365 	uint8_t cmd_lower_col =
366 	    SSDFB_CMD_SET_LOWER_COLUMN_START_ADDRESS_BASE + (fromcol & 0xf);
367 	uint8_t cmd_page;
368 	uint8_t data[2];
369 	uint8_t *colp;
370 	uint8_t *endp;
371 	int error;
372 
373 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
374 	if (error)
375 		return error;
376 	while (frompage <= topage) {
377 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
378 		    sc->sc_i2c_addr, &cc, sizeof(cc),
379 		    &cmd_higher_col, sizeof(cmd_higher_col), flags);
380 		if (error)
381 			goto out;
382 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
383 		    sc->sc_i2c_addr, &cc, sizeof(cc),
384 		    &cmd_lower_col, sizeof(cmd_lower_col), flags);
385 		if (error)
386 			goto out;
387 		cmd_page = SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage;
388 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
389 		    sc->sc_i2c_addr, &cc, sizeof(cc),
390 		    &cmd_page, sizeof(cmd_page), flags);
391 		if (error)
392 			goto out;
393 		colp = p;
394 		endp = colp + len;
395 		if (len & 1) {
396 			data[0] = *colp++;
397 			error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
398 			    sc->sc_i2c_addr, &cb, sizeof(cb), data, 1, flags);
399 			if (error)
400 				goto out;
401 		}
402 		while (colp < endp) {
403 			/*
404 			 * Send two bytes at a time. We can't use colp directly
405 			 * because i2c controllers sometimes have data alignment
406 			 * requirements.
407 			 */
408 			data[0] = *colp++;
409 			data[1] = *colp++;
410 			error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
411 			    sc->sc_i2c_addr, &cb, sizeof(cb), data, 2, flags);
412 			if (error)
413 				goto out;
414 		}
415 		frompage++;
416 		p += stride;
417 	}
418 out:
419 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
420 
421 	return error;
422 }
423