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/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/malloc.h>
34 
35 #include <dev/iicbus/iicbus.h>
36 #include <dev/iicbus/iiconf.h>
37 
38 #include <linux/device.h>
39 #include <linux/i2c.h>
40 #include <linux/i2c-algo-bit.h>
41 #include <linux/list.h>
42 #include <linux/pci.h>
43 
44 #include "iicbus_if.h"
45 #include "iicbb_if.h"
46 #include "lkpi_iic_if.h"
47 
48 static void lkpi_iicbb_setsda(device_t dev, int val);
49 static void lkpi_iicbb_setscl(device_t dev, int val);
50 static int lkpi_iicbb_getscl(device_t dev);
51 static int lkpi_iicbb_getsda(device_t dev);
52 static int lkpi_iicbb_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr);
53 static int lkpi_iicbb_pre_xfer(device_t dev);
54 static void lkpi_iicbb_post_xfer(device_t dev);
55 
56 struct lkpi_iicbb_softc {
57 	device_t		iicbb;
58 	struct i2c_adapter	*adapter;
59 };
60 
61 static struct sx lkpi_sx_i2cbb;
62 
63 static void
64 lkpi_sysinit_i2cbb(void *arg __unused)
65 {
66 
67 	sx_init(&lkpi_sx_i2cbb, "lkpi-i2cbb");
68 }
69 
70 static void
71 lkpi_sysuninit_i2cbb(void *arg __unused)
72 {
73 
74 	sx_destroy(&lkpi_sx_i2cbb);
75 }
76 
77 SYSINIT(lkpi_i2cbb, SI_SUB_DRIVERS, SI_ORDER_ANY,
78     lkpi_sysinit_i2cbb, NULL);
79 SYSUNINIT(lkpi_i2cbb, SI_SUB_DRIVERS, SI_ORDER_ANY,
80     lkpi_sysuninit_i2cbb, NULL);
81 
82 static int
83 lkpi_iicbb_probe(device_t dev)
84 {
85 
86 	device_set_desc(dev, "LinuxKPI I2CBB");
87 	return (BUS_PROBE_NOWILDCARD);
88 }
89 
90 static int
91 lkpi_iicbb_attach(device_t dev)
92 {
93 	struct lkpi_iicbb_softc *sc;
94 
95 	sc = device_get_softc(dev);
96 	sc->iicbb = device_add_child(dev, "iicbb", -1);
97 	if (sc->iicbb == NULL) {
98 		device_printf(dev, "Couldn't add iicbb child, aborting\n");
99 		return (ENXIO);
100 	}
101 	bus_generic_attach(dev);
102 	return (0);
103 }
104 
105 static int
106 lkpi_iicbb_detach(device_t dev)
107 {
108 	struct lkpi_iicbb_softc *sc;
109 
110 	sc = device_get_softc(dev);
111 	if (sc->iicbb)
112 		device_delete_child(dev, sc->iicbb);
113 	return (0);
114 }
115 
116 static int
117 lkpi_iicbb_add_adapter(device_t dev, struct i2c_adapter *adapter)
118 {
119 	struct lkpi_iicbb_softc *sc;
120 	struct i2c_algo_bit_data *algo_data;
121 
122 	sc = device_get_softc(dev);
123 	sc->adapter = adapter;
124 
125 	/*
126 	 * Set iicbb timing parameters deriving speed from the protocol delay.
127 	 */
128 	algo_data = adapter->algo_data;
129 	if (algo_data->udelay != 0)
130 		IICBUS_RESET(sc->iicbb, 1000000 / algo_data->udelay, 0, NULL);
131 	return (0);
132 }
133 
134 static struct i2c_adapter *
135 lkpi_iicbb_get_adapter(device_t dev)
136 {
137 	struct lkpi_iicbb_softc *sc;
138 
139 	sc = device_get_softc(dev);
140 	return (sc->adapter);
141 }
142 
143 static device_method_t lkpi_iicbb_methods[] = {
144 	/* device interface */
145 	DEVMETHOD(device_probe,		lkpi_iicbb_probe),
146 	DEVMETHOD(device_attach,	lkpi_iicbb_attach),
147 	DEVMETHOD(device_detach,	lkpi_iicbb_detach),
148 	DEVMETHOD(device_suspend,	bus_generic_suspend),
149 	DEVMETHOD(device_resume,	bus_generic_resume),
150 
151 	/* iicbb interface */
152 	DEVMETHOD(iicbb_setsda,		lkpi_iicbb_setsda),
153 	DEVMETHOD(iicbb_setscl,		lkpi_iicbb_setscl),
154 	DEVMETHOD(iicbb_getsda,		lkpi_iicbb_getsda),
155 	DEVMETHOD(iicbb_getscl,		lkpi_iicbb_getscl),
156 	DEVMETHOD(iicbb_reset,		lkpi_iicbb_reset),
157 	DEVMETHOD(iicbb_pre_xfer,	lkpi_iicbb_pre_xfer),
158 	DEVMETHOD(iicbb_post_xfer,	lkpi_iicbb_post_xfer),
159 
160 	/* lkpi_iicbb interface */
161 	DEVMETHOD(lkpi_iic_add_adapter,	lkpi_iicbb_add_adapter),
162 	DEVMETHOD(lkpi_iic_get_adapter,	lkpi_iicbb_get_adapter),
163 
164 	DEVMETHOD_END
165 };
166 
167 driver_t lkpi_iicbb_driver = {
168 	"lkpi_iicbb",
169 	lkpi_iicbb_methods,
170 	sizeof(struct lkpi_iicbb_softc),
171 };
172 
173 DRIVER_MODULE(lkpi_iicbb, drmn, lkpi_iicbb_driver, 0, 0);
174 DRIVER_MODULE(lkpi_iicbb, drm, lkpi_iicbb_driver, 0, 0);
175 DRIVER_MODULE(iicbb, lkpi_iicbb, iicbb_driver, 0, 0);
176 MODULE_DEPEND(linuxkpi, iicbb, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
177 
178 static void
179 lkpi_iicbb_setsda(device_t dev, int val)
180 {
181 	struct lkpi_iicbb_softc *sc;
182 	struct i2c_algo_bit_data *algo_data;
183 
184 	sc = device_get_softc(dev);
185 	algo_data = sc->adapter->algo_data;
186 	algo_data->setsda(algo_data->data, val);
187 }
188 
189 static void
190 lkpi_iicbb_setscl(device_t dev, int val)
191 {
192 	struct lkpi_iicbb_softc *sc;
193 	struct i2c_algo_bit_data *algo_data;
194 
195 	sc = device_get_softc(dev);
196 	algo_data = sc->adapter->algo_data;
197 	algo_data->setscl(algo_data->data, val);
198 }
199 
200 static int
201 lkpi_iicbb_getscl(device_t dev)
202 {
203 	struct lkpi_iicbb_softc *sc;
204 	struct i2c_algo_bit_data *algo_data;
205 	int ret;
206 
207 	sc = device_get_softc(dev);
208 	algo_data = sc->adapter->algo_data;
209 	ret = algo_data->getscl(algo_data->data);
210 	return (ret);
211 }
212 
213 static int
214 lkpi_iicbb_getsda(device_t dev)
215 {
216 	struct lkpi_iicbb_softc *sc;
217 	struct i2c_algo_bit_data *algo_data;
218 	int ret;
219 
220 	sc = device_get_softc(dev);
221 	algo_data = sc->adapter->algo_data;
222 	ret = algo_data->getsda(algo_data->data);
223 	return (ret);
224 }
225 
226 static int
227 lkpi_iicbb_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
228 {
229 
230 	/* That doesn't seems to be supported in linux */
231 	return (0);
232 }
233 
234 static int
235 lkpi_iicbb_pre_xfer(device_t dev)
236 {
237 	struct lkpi_iicbb_softc *sc;
238 	struct i2c_algo_bit_data *algo_data;
239 	int rc = 0;
240 
241 	sc = device_get_softc(dev);
242 	algo_data = sc->adapter->algo_data;
243 	if (algo_data->pre_xfer != 0)
244 		rc = algo_data->pre_xfer(sc->adapter);
245 	return (rc);
246 }
247 
248 static void
249 lkpi_iicbb_post_xfer(device_t dev)
250 {
251 	struct lkpi_iicbb_softc *sc;
252 	struct i2c_algo_bit_data *algo_data;
253 
254 	sc = device_get_softc(dev);
255 	algo_data = sc->adapter->algo_data;
256 	if (algo_data->post_xfer != NULL)
257 		algo_data->post_xfer(sc->adapter);
258 }
259 
260 int
261 lkpi_i2cbb_transfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
262     int nmsgs)
263 {
264 	struct iic_msg *bsd_msgs;
265 	int ret = ENXIO;
266 
267 	linux_set_current(curthread);
268 
269 	bsd_msgs = malloc(sizeof(struct iic_msg) * nmsgs,
270 	    M_DEVBUF, M_WAITOK | M_ZERO);
271 
272 	for (int i = 0; i < nmsgs; i++) {
273 		bsd_msgs[i].slave = msgs[i].addr << 1;
274 		bsd_msgs[i].len = msgs[i].len;
275 		bsd_msgs[i].buf = msgs[i].buf;
276 		if (msgs[i].flags & I2C_M_RD)
277 			bsd_msgs[i].flags |= IIC_M_RD;
278 		if (msgs[i].flags & I2C_M_NOSTART)
279 			bsd_msgs[i].flags |= IIC_M_NOSTART;
280 	}
281 
282 	for (int unit = 0; ; unit++) {
283 		device_t child;
284 		struct lkpi_iicbb_softc *sc;
285 
286 		child = device_find_child(adapter->dev.parent->bsddev,
287 		    "lkpi_iicbb", unit);
288 		if (child == NULL)
289 			break;
290 		if (adapter == LKPI_IIC_GET_ADAPTER(child)) {
291 			sc = device_get_softc(child);
292 			ret = IICBUS_TRANSFER(sc->iicbb, bsd_msgs, nmsgs);
293 			ret = iic2errno(ret);
294 			break;
295 		}
296 	}
297 
298 	free(bsd_msgs, M_DEVBUF);
299 
300 	if (ret != 0)
301 		return (-ret);
302 	return (nmsgs);
303 }
304 
305 int
306 lkpi_i2c_bit_add_bus(struct i2c_adapter *adapter)
307 {
308 	device_t lkpi_iicbb;
309 	int error;
310 
311 	if (bootverbose)
312 		device_printf(adapter->dev.parent->bsddev,
313 		    "Adding i2c adapter %s\n", adapter->name);
314 	sx_xlock(&lkpi_sx_i2cbb);
315 	lkpi_iicbb = device_add_child(adapter->dev.parent->bsddev, "lkpi_iicbb", -1);
316 	if (lkpi_iicbb == NULL) {
317 		device_printf(adapter->dev.parent->bsddev, "Couldn't add lkpi_iicbb\n");
318 		sx_xunlock(&lkpi_sx_i2cbb);
319 		return (ENXIO);
320 	}
321 
322 	bus_topo_lock();
323 	error = bus_generic_attach(adapter->dev.parent->bsddev);
324 	bus_topo_unlock();
325 	if (error) {
326 		device_printf(adapter->dev.parent->bsddev,
327 		  "failed to attach child: error %d\n", error);
328 		sx_xunlock(&lkpi_sx_i2cbb);
329 		return (ENXIO);
330 	}
331 	LKPI_IIC_ADD_ADAPTER(lkpi_iicbb, adapter);
332 	sx_xunlock(&lkpi_sx_i2cbb);
333 	return (0);
334 }
335