1 /*-
2 * Copyright (c) 2021 Beckhoff Automation GmbH & Co. KG
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 *
25 */
26
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/bus.h>
30 #include <sys/malloc.h>
31
32 #include <dev/iicbus/iicbus.h>
33 #include <dev/iicbus/iiconf.h>
34
35 #include <linux/device.h>
36 #include <linux/i2c.h>
37 #include <linux/i2c-algo-bit.h>
38 #include <linux/list.h>
39 #include <linux/pci.h>
40
41 #include "iicbus_if.h"
42 #include "iicbb_if.h"
43 #include "lkpi_iic_if.h"
44
45 static int lkpi_i2c_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs);
46 static int lkpi_i2c_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr);
47
48 struct lkpi_iic_softc {
49 device_t iicbus;
50 struct i2c_adapter *adapter;
51 };
52
53 static struct sx lkpi_sx_i2c;
54
55 static void
lkpi_sysinit_i2c(void * arg __unused)56 lkpi_sysinit_i2c(void *arg __unused)
57 {
58
59 sx_init(&lkpi_sx_i2c, "lkpi-i2c");
60 }
61
62 static void
lkpi_sysuninit_i2c(void * arg __unused)63 lkpi_sysuninit_i2c(void *arg __unused)
64 {
65
66 sx_destroy(&lkpi_sx_i2c);
67 }
68
69 SYSINIT(lkpi_i2c, SI_SUB_DRIVERS, SI_ORDER_ANY,
70 lkpi_sysinit_i2c, NULL);
71 SYSUNINIT(lkpi_i2c, SI_SUB_DRIVERS, SI_ORDER_ANY,
72 lkpi_sysuninit_i2c, NULL);
73
74 static int
lkpi_iic_probe(device_t dev)75 lkpi_iic_probe(device_t dev)
76 {
77
78 device_set_desc(dev, "LinuxKPI I2C");
79 return (BUS_PROBE_NOWILDCARD);
80 }
81
82 static int
lkpi_iic_attach(device_t dev)83 lkpi_iic_attach(device_t dev)
84 {
85 struct lkpi_iic_softc *sc;
86
87 sc = device_get_softc(dev);
88 sc->iicbus = device_add_child(dev, "iicbus", -1);
89 if (sc->iicbus == NULL) {
90 device_printf(dev, "Couldn't add iicbus child, aborting\n");
91 return (ENXIO);
92 }
93 bus_generic_attach(dev);
94 return (0);
95 }
96
97 static int
lkpi_iic_detach(device_t dev)98 lkpi_iic_detach(device_t dev)
99 {
100 struct lkpi_iic_softc *sc;
101
102 sc = device_get_softc(dev);
103 if (sc->iicbus)
104 device_delete_child(dev, sc->iicbus);
105 return (0);
106 }
107
108 static int
lkpi_iic_add_adapter(device_t dev,struct i2c_adapter * adapter)109 lkpi_iic_add_adapter(device_t dev, struct i2c_adapter *adapter)
110 {
111 struct lkpi_iic_softc *sc;
112
113 sc = device_get_softc(dev);
114 sc->adapter = adapter;
115
116 return (0);
117 }
118
119 static struct i2c_adapter *
lkpi_iic_get_adapter(device_t dev)120 lkpi_iic_get_adapter(device_t dev)
121 {
122 struct lkpi_iic_softc *sc;
123
124 sc = device_get_softc(dev);
125 return (sc->adapter);
126 }
127
128 static device_method_t lkpi_iic_methods[] = {
129 /* device interface */
130 DEVMETHOD(device_probe, lkpi_iic_probe),
131 DEVMETHOD(device_attach, lkpi_iic_attach),
132 DEVMETHOD(device_detach, lkpi_iic_detach),
133 DEVMETHOD(device_suspend, bus_generic_suspend),
134 DEVMETHOD(device_resume, bus_generic_resume),
135
136 /* iicbus interface */
137 DEVMETHOD(iicbus_transfer, lkpi_i2c_transfer),
138 DEVMETHOD(iicbus_reset, lkpi_i2c_reset),
139 DEVMETHOD(iicbus_callback, iicbus_null_callback),
140
141 /* lkpi_iic interface */
142 DEVMETHOD(lkpi_iic_add_adapter, lkpi_iic_add_adapter),
143 DEVMETHOD(lkpi_iic_get_adapter, lkpi_iic_get_adapter),
144
145 DEVMETHOD_END
146 };
147
148 driver_t lkpi_iic_driver = {
149 "lkpi_iic",
150 lkpi_iic_methods,
151 sizeof(struct lkpi_iic_softc),
152 };
153
154 DRIVER_MODULE(lkpi_iic, drmn, lkpi_iic_driver, 0, 0);
155 DRIVER_MODULE(lkpi_iic, drm, lkpi_iic_driver, 0, 0);
156 DRIVER_MODULE(iicbus, lkpi_iic, iicbus_driver, 0, 0);
157 MODULE_DEPEND(linuxkpi, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
158
159 static int
lkpi_i2c_reset(device_t dev,u_char speed,u_char addr,u_char * oldaddr)160 lkpi_i2c_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
161 {
162
163 /* That doesn't seems to be supported in linux */
164 return (0);
165 }
166
i2c_check_for_quirks(struct i2c_adapter * adapter,struct iic_msg * msgs,uint32_t nmsgs)167 static int i2c_check_for_quirks(struct i2c_adapter *adapter,
168 struct iic_msg *msgs, uint32_t nmsgs)
169 {
170 const struct i2c_adapter_quirks *quirks;
171 device_t dev;
172 int i, max_nmsgs;
173 bool check_len;
174
175 dev = adapter->dev.parent->bsddev;
176 quirks = adapter->quirks;
177 if (quirks == NULL)
178 return (0);
179
180 check_len = true;
181 max_nmsgs = quirks->max_num_msgs;
182
183 if (quirks->flags & I2C_AQ_COMB) {
184 max_nmsgs = 2;
185
186 if (nmsgs == 2) {
187 if (quirks->flags & I2C_AQ_COMB_WRITE_FIRST &&
188 msgs[0].flags & IIC_M_RD) {
189 device_printf(dev,
190 "Error: "
191 "first combined message must be write\n");
192 return (EOPNOTSUPP);
193 }
194 if (quirks->flags & I2C_AQ_COMB_READ_SECOND &&
195 !(msgs[1].flags & IIC_M_RD)) {
196 device_printf(dev,
197 "Error: "
198 "second combined message must be read\n");
199 return (EOPNOTSUPP);
200 }
201
202 if (quirks->flags & I2C_AQ_COMB_SAME_ADDR &&
203 msgs[0].slave != msgs[1].slave) {
204 device_printf(dev,
205 "Error: "
206 "combined message must be use the same "
207 "address\n");
208 return (EOPNOTSUPP);
209 }
210
211 if (quirks->max_comb_1st_msg_len &&
212 msgs[0].len > quirks->max_comb_1st_msg_len) {
213 device_printf(dev,
214 "Error: "
215 "message too long: %hu > %hu max\n",
216 msgs[0].len,
217 quirks->max_comb_1st_msg_len);
218 return (EOPNOTSUPP);
219 }
220 if (quirks->max_comb_2nd_msg_len &&
221 msgs[1].len > quirks->max_comb_2nd_msg_len) {
222 device_printf(dev,
223 "Error: "
224 "message too long: %hu > %hu max\n",
225 msgs[1].len,
226 quirks->max_comb_2nd_msg_len);
227 return (EOPNOTSUPP);
228 }
229
230 check_len = false;
231 }
232 }
233
234 if (max_nmsgs && nmsgs > max_nmsgs) {
235 device_printf(dev,
236 "Error: too many messages: %d > %d max\n",
237 nmsgs, max_nmsgs);
238 return (EOPNOTSUPP);
239 }
240
241 for (i = 0; i < nmsgs; i++) {
242 if (msgs[i].flags & IIC_M_RD) {
243 if (check_len && quirks->max_read_len &&
244 msgs[i].len > quirks->max_read_len) {
245 device_printf(dev,
246 "Error: "
247 "message %d too long: %hu > %hu max\n",
248 i, msgs[i].len, quirks->max_read_len);
249 return (EOPNOTSUPP);
250 }
251 if (quirks->flags & I2C_AQ_NO_ZERO_LEN_READ &&
252 msgs[i].len == 0) {
253 device_printf(dev,
254 "Error: message %d of length 0\n", i);
255 return (EOPNOTSUPP);
256 }
257 } else {
258 if (check_len && quirks->max_write_len &&
259 msgs[i].len > quirks->max_write_len) {
260 device_printf(dev,
261 "Message %d too long: %hu > %hu max\n",
262 i, msgs[i].len, quirks->max_write_len);
263 return (EOPNOTSUPP);
264 }
265 if (quirks->flags & I2C_AQ_NO_ZERO_LEN_WRITE &&
266 msgs[i].len == 0) {
267 device_printf(dev,
268 "Error: message %d of length 0\n", i);
269 return (EOPNOTSUPP);
270 }
271 }
272 }
273
274 return (0);
275 }
276
277 static int
lkpi_i2c_transfer(device_t dev,struct iic_msg * msgs,uint32_t nmsgs)278 lkpi_i2c_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
279 {
280 struct lkpi_iic_softc *sc;
281 struct i2c_msg *linux_msgs;
282 int i, ret = 0;
283
284 sc = device_get_softc(dev);
285 if (sc->adapter == NULL)
286 return (ENXIO);
287 ret = i2c_check_for_quirks(sc->adapter, msgs, nmsgs);
288 if (ret != 0)
289 return (ret);
290 linux_set_current(curthread);
291
292 linux_msgs = malloc(sizeof(struct i2c_msg) * nmsgs,
293 M_DEVBUF, M_WAITOK | M_ZERO);
294
295 for (i = 0; i < nmsgs; i++) {
296 linux_msgs[i].addr = msgs[i].slave >> 1;
297 linux_msgs[i].len = msgs[i].len;
298 linux_msgs[i].buf = msgs[i].buf;
299 if (msgs[i].flags & IIC_M_RD) {
300 linux_msgs[i].flags |= I2C_M_RD;
301 for (int j = 0; j < msgs[i].len; j++)
302 msgs[i].buf[j] = 0;
303 }
304 if (msgs[i].flags & IIC_M_NOSTART)
305 linux_msgs[i].flags |= I2C_M_NOSTART;
306 }
307 ret = i2c_transfer(sc->adapter, linux_msgs, nmsgs);
308 free(linux_msgs, M_DEVBUF);
309
310 if (ret < 0)
311 return (-ret);
312 return (0);
313 }
314
315 int
lkpi_i2c_add_adapter(struct i2c_adapter * adapter)316 lkpi_i2c_add_adapter(struct i2c_adapter *adapter)
317 {
318 device_t lkpi_iic;
319 int error;
320
321 if (adapter->name[0] == '\0')
322 return (-EINVAL);
323 if (bootverbose)
324 device_printf(adapter->dev.parent->bsddev,
325 "Adding i2c adapter %s\n", adapter->name);
326 sx_xlock(&lkpi_sx_i2c);
327 lkpi_iic = device_add_child(adapter->dev.parent->bsddev, "lkpi_iic", -1);
328 if (lkpi_iic == NULL) {
329 device_printf(adapter->dev.parent->bsddev, "Couldn't add lkpi_iic\n");
330 sx_xunlock(&lkpi_sx_i2c);
331 return (ENXIO);
332 }
333
334 bus_topo_lock();
335 error = bus_generic_attach(adapter->dev.parent->bsddev);
336 bus_topo_unlock();
337 if (error) {
338 device_printf(adapter->dev.parent->bsddev,
339 "failed to attach child: error %d\n", error);
340 sx_xunlock(&lkpi_sx_i2c);
341 return (ENXIO);
342 }
343 LKPI_IIC_ADD_ADAPTER(lkpi_iic, adapter);
344 sx_xunlock(&lkpi_sx_i2c);
345 return (0);
346 }
347
348 int
lkpi_i2c_del_adapter(struct i2c_adapter * adapter)349 lkpi_i2c_del_adapter(struct i2c_adapter *adapter)
350 {
351 device_t child;
352 int unit, rv;
353
354 if (adapter == NULL)
355 return (-EINVAL);
356 if (bootverbose)
357 device_printf(adapter->dev.parent->bsddev,
358 "Removing i2c adapter %s\n", adapter->name);
359 sx_xlock(&lkpi_sx_i2c);
360 unit = 0;
361 while ((child = device_find_child(adapter->dev.parent->bsddev, "lkpi_iic", unit++)) != NULL) {
362
363 if (adapter == LKPI_IIC_GET_ADAPTER(child)) {
364 bus_topo_lock();
365 device_delete_child(adapter->dev.parent->bsddev, child);
366 bus_topo_unlock();
367 rv = 0;
368 goto out;
369 }
370 }
371
372 unit = 0;
373 while ((child = device_find_child(adapter->dev.parent->bsddev, "lkpi_iicbb", unit++)) != NULL) {
374
375 if (adapter == LKPI_IIC_GET_ADAPTER(child)) {
376 bus_topo_lock();
377 device_delete_child(adapter->dev.parent->bsddev, child);
378 bus_topo_unlock();
379 rv = 0;
380 goto out;
381 }
382 }
383 rv = -EINVAL;
384 out:
385 sx_xunlock(&lkpi_sx_i2c);
386 return (rv);
387 }
388