xref: /netbsd-src/sys/dev/i2c/ssdfb_i2c.c (revision 2e6662efc3ecfb1f7255046a4ba6166b56b49f7b)
1 /* $NetBSD: ssdfb_i2c.c,v 1.11 2021/08/05 22:31:20 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 1.11 2021/08/05 22:31:20 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 	{ .compat = "solomon,ssd1306fb-i2c",
71 	  .value = SSDFB_PRODUCT_SSD1306_GENERIC },
72 
73 	{ .compat = "sino,sh1106fb-i2c",
74 	  .value = SSDFB_PRODUCT_SH1106_GENERIC },
75 
76 	DEVICE_COMPAT_EOL
77 };
78 
79 static int
ssdfb_i2c_match(device_t parent,cfdata_t match,void * aux)80 ssdfb_i2c_match(device_t parent, cfdata_t match, void *aux)
81 {
82 	struct i2c_attach_args *ia = aux;
83 	int match_result;
84 
85 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
86 		return match_result;
87 
88 	switch (ia->ia_addr) {
89 	case SSDFB_I2C_DEFAULT_ADDR:
90 	case SSDFB_I2C_ALTERNATIVE_ADDR:
91 		return I2C_MATCH_ADDRESS_ONLY;
92 	}
93 
94 	return 0;
95 }
96 
97 static void
ssdfb_i2c_attach(device_t parent,device_t self,void * aux)98 ssdfb_i2c_attach(device_t parent, device_t self, void *aux)
99 {
100 	struct ssdfb_i2c_softc *sc = device_private(self);
101 	struct cfdata *cf = device_cfdata(self);
102 	struct i2c_attach_args *ia = aux;
103 	int flags = cf->cf_flags;
104 
105 	if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN) {
106 		const struct device_compatible_entry *dce =
107 		    iic_compatible_lookup(ia, compat_data);
108 		if (dce != NULL) {
109 			flags |= (int)dce->value;
110 		}
111 	}
112 	if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN)
113 		flags |= SSDFB_PRODUCT_SSD1306_GENERIC;
114 
115 	flags |= SSDFB_ATTACH_FLAG_MPSAFE;
116 	sc->sc.sc_dev = self;
117 	sc->sc_i2c_tag = ia->ia_tag;
118 	sc->sc_i2c_addr = ia->ia_addr;
119 	sc->sc.sc_cookie = (void *)sc;
120 	sc->sc.sc_cmd = ssdfb_i2c_cmd;
121 	sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect;
122 
123 	ssdfb_attach(&sc->sc, flags);
124 }
125 
126 static int
ssdfb_i2c_detach(device_t self,int flags)127 ssdfb_i2c_detach(device_t self, int flags)
128 {
129 	struct ssdfb_i2c_softc *sc = device_private(self);
130 
131 	return ssdfb_detach(&sc->sc);
132 }
133 
134 static int
ssdfb_i2c_probe_transfer_size(struct ssdfb_i2c_softc * sc,bool usepoll)135 ssdfb_i2c_probe_transfer_size(struct ssdfb_i2c_softc *sc, bool usepoll)
136 {
137 	int flags = usepoll ? I2C_F_POLL : 0;
138 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
139 	int error;
140 	uint8_t buf[128];
141 	size_t len;
142 
143 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
144 	if (error)
145 		return error;
146 	len = sizeof(buf);
147 	memset(buf, 0, len);
148 	while (len > 0) {
149 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
150 		    sc->sc_i2c_addr, &cb, sizeof(cb), buf, len, flags);
151 		if (!error) {
152 			break;
153 		}
154 		len >>= 1;
155 	}
156 	if (!error && len < 2) {
157 		error = E2BIG;
158 	} else {
159 		sc->sc_transfer_size = len;
160 	}
161 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
162 
163 	return error;
164 }
165 
166 static int
ssdfb_i2c_transfer(struct ssdfb_i2c_softc * sc,uint8_t cb,uint8_t * data,size_t len,int flags)167 ssdfb_i2c_transfer(struct ssdfb_i2c_softc *sc, uint8_t cb, uint8_t *data,
168 		   size_t len, int flags)
169 {
170 	int error;
171 	size_t xfer_size = sc->sc_transfer_size;
172 
173 	while (len >= xfer_size) {
174 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
175 		    sc->sc_i2c_addr, &cb, sizeof(cb), data, xfer_size, flags);
176 		if (error)
177 			return error;
178 		len -= xfer_size;
179 		data += xfer_size;
180 	}
181 	if (len > 0) {
182 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
183 		    sc->sc_i2c_addr, &cb, sizeof(cb), data, len, flags);
184 	}
185 
186 	return error;
187 }
188 
189 static int
ssdfb_i2c_cmd(void * cookie,uint8_t * cmd,size_t len,bool usepoll)190 ssdfb_i2c_cmd(void *cookie, uint8_t *cmd, size_t len, bool usepoll)
191 {
192 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
193 	int flags = usepoll ? I2C_F_POLL : 0;
194 	uint8_t cb = 0;
195 	int error;
196 
197 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
198 	if (error)
199 		return error;
200 	error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
201 	    sc->sc_i2c_addr, &cb, sizeof(cb), cmd, len, flags);
202 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
203 
204 	return error;
205 }
206 
207 static int
ssdfb_i2c_transfer_rect(void * cookie,uint8_t fromcol,uint8_t tocol,uint8_t frompage,uint8_t topage,uint8_t * p,size_t stride,bool usepoll)208 ssdfb_i2c_transfer_rect(void *cookie, uint8_t fromcol, uint8_t tocol,
209     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
210 {
211 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
212 	uint8_t cmd[2];
213 	int error;
214 
215 	/*
216 	 * Test if large transfers are supported by the parent i2c bus and
217 	 * pick the fastest transfer routine for subsequent invocations.
218 	 */
219 	switch (sc->sc.sc_p->p_controller_id) {
220 	case SSDFB_CONTROLLER_SSD1306:
221 		sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect_ssd1306;
222 		break;
223 	case SSDFB_CONTROLLER_SH1106:
224 		sc->sc.sc_transfer_rect = ssdfb_i2c_transfer_rect_sh1106;
225 		break;
226 	default:
227 		sc->sc.sc_transfer_rect = ssdfb_smbus_transfer_rect;
228 		break;
229 	}
230 
231 	if (sc->sc.sc_transfer_rect != ssdfb_smbus_transfer_rect) {
232 		error = ssdfb_i2c_probe_transfer_size(sc, usepoll);
233 		if (error)
234 			return error;
235 		aprint_verbose_dev(sc->sc.sc_dev, "%zd-byte transfers\n",
236 		    sc->sc_transfer_size);
237 		if (sc->sc_transfer_size == 2) {
238 			sc->sc.sc_transfer_rect = ssdfb_smbus_transfer_rect;
239 		}
240 	}
241 
242 	/*
243 	 * Set addressing mode for SSD1306.
244 	 */
245 	if (sc->sc.sc_p->p_controller_id == SSDFB_CONTROLLER_SSD1306) {
246 		cmd[0] = SSD1306_CMD_SET_MEMORY_ADDRESSING_MODE;
247 		cmd[1] = sc->sc.sc_transfer_rect
248 		    == ssdfb_i2c_transfer_rect_ssd1306
249 		    ? SSD1306_MEMORY_ADDRESSING_MODE_HORIZONTAL
250 		    : SSD1306_MEMORY_ADDRESSING_MODE_PAGE;
251 		error = ssdfb_i2c_cmd(cookie, cmd, sizeof(cmd), usepoll);
252 		if (error)
253 			return error;
254 	}
255 
256 	return sc->sc.sc_transfer_rect(cookie, fromcol, tocol, frompage, topage,
257 	    p, stride, usepoll);
258 }
259 
260 
261 static int
ssdfb_i2c_transfer_rect_ssd1306(void * cookie,uint8_t fromcol,uint8_t tocol,uint8_t frompage,uint8_t topage,uint8_t * p,size_t stride,bool usepoll)262 ssdfb_i2c_transfer_rect_ssd1306(void *cookie, uint8_t fromcol, uint8_t tocol,
263     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
264 {
265 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
266 	int flags = usepoll ? I2C_F_POLL : 0;
267 	uint8_t cc = 0;
268 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
269 	size_t len = tocol + 1 - fromcol;
270 	int error;
271 	/*
272 	 * SSD1306 does not implement the Continuation bit correctly.
273 	 * The SH1106 protocol defines that a control byte WITH Co
274 	 * set must be inserted between each command. But SSD1306
275 	 * fails to parse the commands if we do that.
276 	 */
277 	uint8_t cmds[] = {
278 		SSD1306_CMD_SET_COLUMN_ADDRESS,
279 		fromcol, tocol,
280 		SSD1306_CMD_SET_PAGE_ADDRESS,
281 		frompage, topage
282 	};
283 
284 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
285 	if (error)
286 		return error;
287 	error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
288 	    sc->sc_i2c_addr, &cc, sizeof(cc), cmds, sizeof(cmds), flags);
289 	if (error)
290 		goto out;
291 	while (frompage <= topage) {
292 		error = ssdfb_i2c_transfer(sc, cb, p, len, flags);
293 		if (error)
294 			goto out;
295 		frompage++;
296 		p += stride;
297 	}
298 out:
299 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
300 
301 	return error;
302 }
303 
304 static int
ssdfb_i2c_transfer_rect_sh1106(void * cookie,uint8_t fromcol,uint8_t tocol,uint8_t frompage,uint8_t topage,uint8_t * p,size_t stride,bool usepoll)305 ssdfb_i2c_transfer_rect_sh1106(void *cookie, uint8_t fromcol, uint8_t tocol,
306     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
307 {
308 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
309 	int flags = usepoll ? I2C_F_POLL : 0;
310 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
311 	uint8_t cc = SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK;
312 	size_t len = tocol + 1 - fromcol;
313 	int error;
314 	uint8_t cmds[] = {
315 		SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage,
316 		SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK,
317 		SSDFB_CMD_SET_HIGHER_COLUMN_START_ADDRESS_BASE + (fromcol >> 4),
318 		SSDFB_I2C_CTRL_BYTE_CONTINUATION_MASK,
319 		SSDFB_CMD_SET_LOWER_COLUMN_START_ADDRESS_BASE + (fromcol & 0xf)
320 	};
321 
322 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
323 	if (error)
324 		return error;
325 	while (frompage <= topage) {
326 		cmds[0] = SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage;
327 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
328 		    sc->sc_i2c_addr, &cc, sizeof(cc), cmds, sizeof(cmds), flags);
329 		if (error)
330 			goto out;
331 		error = ssdfb_i2c_transfer(sc, cb, p, len, flags);
332 		if (error)
333 			goto out;
334 		frompage++;
335 		p += stride;
336 	}
337 out:
338 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
339 
340 	return error;
341 }
342 
343 /*
344  * If the parent is an SMBus, then we can only send 2 bytes
345  * of payload per txn. The SSD1306 triple byte commands are
346  * not available so we have to use PAGE addressing mode
347  * and split data into multiple txns.
348  * This is ugly and slow but it's the best we can do.
349  */
350 static int
ssdfb_smbus_transfer_rect(void * cookie,uint8_t fromcol,uint8_t tocol,uint8_t frompage,uint8_t topage,uint8_t * p,size_t stride,bool usepoll)351 ssdfb_smbus_transfer_rect(void *cookie, uint8_t fromcol, uint8_t tocol,
352     uint8_t frompage, uint8_t topage, uint8_t *p, size_t stride, bool usepoll)
353 {
354 	struct ssdfb_i2c_softc *sc = (struct ssdfb_i2c_softc *)cookie;
355 	int flags = usepoll ? I2C_F_POLL : 0;
356 	uint8_t cb = SSDFB_I2C_CTRL_BYTE_DATA_MASK;
357 	uint8_t cc = 0;
358 	size_t len = tocol + 1 - fromcol;
359 	uint8_t cmd_higher_col =
360 	    SSDFB_CMD_SET_HIGHER_COLUMN_START_ADDRESS_BASE + (fromcol >> 4);
361 	uint8_t cmd_lower_col =
362 	    SSDFB_CMD_SET_LOWER_COLUMN_START_ADDRESS_BASE + (fromcol & 0xf);
363 	uint8_t cmd_page;
364 	uint8_t data[2];
365 	uint8_t *colp;
366 	uint8_t *endp;
367 	int error;
368 
369 	error = iic_acquire_bus(sc->sc_i2c_tag, flags);
370 	if (error)
371 		return error;
372 	while (frompage <= topage) {
373 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
374 		    sc->sc_i2c_addr, &cc, sizeof(cc),
375 		    &cmd_higher_col, sizeof(cmd_higher_col), flags);
376 		if (error)
377 			goto out;
378 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
379 		    sc->sc_i2c_addr, &cc, sizeof(cc),
380 		    &cmd_lower_col, sizeof(cmd_lower_col), flags);
381 		if (error)
382 			goto out;
383 		cmd_page = SSDFB_CMD_SET_PAGE_START_ADDRESS_BASE + frompage;
384 		error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
385 		    sc->sc_i2c_addr, &cc, sizeof(cc),
386 		    &cmd_page, sizeof(cmd_page), flags);
387 		if (error)
388 			goto out;
389 		colp = p;
390 		endp = colp + len;
391 		if (len & 1) {
392 			data[0] = *colp++;
393 			error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
394 			    sc->sc_i2c_addr, &cb, sizeof(cb), data, 1, flags);
395 			if (error)
396 				goto out;
397 		}
398 		while (colp < endp) {
399 			/*
400 			 * Send two bytes at a time. We can't use colp directly
401 			 * because i2c controllers sometimes have data alignment
402 			 * requirements.
403 			 */
404 			data[0] = *colp++;
405 			data[1] = *colp++;
406 			error = iic_exec(sc->sc_i2c_tag, I2C_OP_WRITE_WITH_STOP,
407 			    sc->sc_i2c_addr, &cb, sizeof(cb), data, 2, flags);
408 			if (error)
409 				goto out;
410 		}
411 		frompage++;
412 		p += stride;
413 	}
414 out:
415 	(void) iic_release_bus(sc->sc_i2c_tag, flags);
416 
417 	return error;
418 }
419