xref: /openbmc/u-boot/drivers/spi/spi-uclass.c (revision 2d2811c2)
1 /*
2  * Copyright (c) 2014 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <fdtdec.h>
11 #include <malloc.h>
12 #include <spi.h>
13 #include <dm/device-internal.h>
14 #include <dm/uclass-internal.h>
15 #include <dm/lists.h>
16 #include <dm/util.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
21 {
22 	struct dm_spi_ops *ops;
23 	int ret;
24 
25 	ops = spi_get_ops(bus);
26 	if (ops->set_speed)
27 		ret = ops->set_speed(bus, speed);
28 	else
29 		ret = -EINVAL;
30 	if (ret) {
31 		printf("Cannot set speed (err=%d)\n", ret);
32 		return ret;
33 	}
34 
35 	if (ops->set_mode)
36 		ret = ops->set_mode(bus, mode);
37 	else
38 		ret = -EINVAL;
39 	if (ret) {
40 		printf("Cannot set mode (err=%d)\n", ret);
41 		return ret;
42 	}
43 
44 	return 0;
45 }
46 
47 int dm_spi_claim_bus(struct udevice *dev)
48 {
49 	struct udevice *bus = dev->parent;
50 	struct dm_spi_ops *ops = spi_get_ops(bus);
51 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
52 	struct spi_slave *slave = dev_get_parent_priv(dev);
53 	int speed;
54 	int ret;
55 
56 	speed = slave->max_hz;
57 	if (spi->max_hz) {
58 		if (speed)
59 			speed = min(speed, (int)spi->max_hz);
60 		else
61 			speed = spi->max_hz;
62 	}
63 	if (!speed)
64 		speed = 100000;
65 	if (speed != slave->speed) {
66 		ret = spi_set_speed_mode(bus, speed, slave->mode);
67 		if (ret)
68 			return ret;
69 		slave->speed = speed;
70 	}
71 
72 	return ops->claim_bus ? ops->claim_bus(dev) : 0;
73 }
74 
75 void dm_spi_release_bus(struct udevice *dev)
76 {
77 	struct udevice *bus = dev->parent;
78 	struct dm_spi_ops *ops = spi_get_ops(bus);
79 
80 	if (ops->release_bus)
81 		ops->release_bus(dev);
82 }
83 
84 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
85 		const void *dout, void *din, unsigned long flags)
86 {
87 	struct udevice *bus = dev->parent;
88 
89 	if (bus->uclass->uc_drv->id != UCLASS_SPI)
90 		return -EOPNOTSUPP;
91 
92 	return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
93 }
94 
95 int spi_claim_bus(struct spi_slave *slave)
96 {
97 	return dm_spi_claim_bus(slave->dev);
98 }
99 
100 void spi_release_bus(struct spi_slave *slave)
101 {
102 	dm_spi_release_bus(slave->dev);
103 }
104 
105 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
106 	     const void *dout, void *din, unsigned long flags)
107 {
108 	return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
109 }
110 
111 static int spi_child_post_bind(struct udevice *dev)
112 {
113 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
114 
115 	if (dev->of_offset == -1)
116 		return 0;
117 
118 	return spi_slave_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, plat);
119 }
120 
121 static int spi_post_probe(struct udevice *bus)
122 {
123 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
124 
125 	spi->max_hz = fdtdec_get_int(gd->fdt_blob, bus->of_offset,
126 				     "spi-max-frequency", 0);
127 
128 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
129 	struct dm_spi_ops *ops = spi_get_ops(bus);
130 
131 
132 	if (ops->claim_bus)
133 		ops->claim_bus += gd->reloc_off;
134 	if (ops->release_bus)
135 		ops->release_bus += gd->reloc_off;
136 	if (ops->set_wordlen)
137 		ops->set_wordlen += gd->reloc_off;
138 	if (ops->xfer)
139 		ops->xfer += gd->reloc_off;
140 	if (ops->set_speed)
141 		ops->set_speed += gd->reloc_off;
142 	if (ops->set_mode)
143 		ops->set_mode += gd->reloc_off;
144 	if (ops->cs_info)
145 		ops->cs_info += gd->reloc_off;
146 #endif
147 
148 	return 0;
149 }
150 
151 static int spi_child_pre_probe(struct udevice *dev)
152 {
153 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
154 	struct spi_slave *slave = dev_get_parent_priv(dev);
155 
156 	/*
157 	 * This is needed because we pass struct spi_slave around the place
158 	 * instead slave->dev (a struct udevice). So we have to have some
159 	 * way to access the slave udevice given struct spi_slave. Once we
160 	 * change the SPI API to use udevice instead of spi_slave, we can
161 	 * drop this.
162 	 */
163 	slave->dev = dev;
164 
165 	slave->max_hz = plat->max_hz;
166 	slave->mode = plat->mode;
167 	slave->mode_rx = plat->mode_rx;
168 	slave->wordlen = SPI_DEFAULT_WORDLEN;
169 
170 	return 0;
171 }
172 
173 int spi_chip_select(struct udevice *dev)
174 {
175 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
176 
177 	return plat ? plat->cs : -ENOENT;
178 }
179 
180 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
181 {
182 	struct udevice *dev;
183 
184 	for (device_find_first_child(bus, &dev); dev;
185 	     device_find_next_child(&dev)) {
186 		struct dm_spi_slave_platdata *plat;
187 
188 		plat = dev_get_parent_platdata(dev);
189 		debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
190 		if (plat->cs == cs) {
191 			*devp = dev;
192 			return 0;
193 		}
194 	}
195 
196 	return -ENODEV;
197 }
198 
199 int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
200 {
201 	struct spi_cs_info info;
202 	struct udevice *bus;
203 	int ret;
204 
205 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
206 	if (ret) {
207 		debug("%s: No bus %d\n", __func__, busnum);
208 		return ret;
209 	}
210 
211 	return spi_cs_info(bus, cs, &info);
212 }
213 
214 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
215 {
216 	struct spi_cs_info local_info;
217 	struct dm_spi_ops *ops;
218 	int ret;
219 
220 	if (!info)
221 		info = &local_info;
222 
223 	/* If there is a device attached, return it */
224 	info->dev = NULL;
225 	ret = spi_find_chip_select(bus, cs, &info->dev);
226 	if (!ret)
227 		return 0;
228 
229 	/*
230 	 * Otherwise ask the driver. For the moment we don't have CS info.
231 	 * When we do we could provide the driver with a helper function
232 	 * to figure out what chip selects are valid, or just handle the
233 	 * request.
234 	 */
235 	ops = spi_get_ops(bus);
236 	if (ops->cs_info)
237 		return ops->cs_info(bus, cs, info);
238 
239 	/*
240 	 * We could assume there is at least one valid chip select, but best
241 	 * to be sure and return an error in this case. The driver didn't
242 	 * care enough to tell us.
243 	 */
244 	return -ENODEV;
245 }
246 
247 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
248 			struct udevice **devp)
249 {
250 	struct udevice *bus, *dev;
251 	int ret;
252 
253 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
254 	if (ret) {
255 		debug("%s: No bus %d\n", __func__, busnum);
256 		return ret;
257 	}
258 	ret = spi_find_chip_select(bus, cs, &dev);
259 	if (ret) {
260 		debug("%s: No cs %d\n", __func__, cs);
261 		return ret;
262 	}
263 	*busp = bus;
264 	*devp = dev;
265 
266 	return ret;
267 }
268 
269 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
270 		       const char *drv_name, const char *dev_name,
271 		       struct udevice **busp, struct spi_slave **devp)
272 {
273 	struct udevice *bus, *dev;
274 	struct dm_spi_slave_platdata *plat;
275 	bool created = false;
276 	int ret;
277 
278 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
279 	if (ret) {
280 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
281 		return ret;
282 	}
283 	ret = spi_find_chip_select(bus, cs, &dev);
284 
285 	/*
286 	 * If there is no such device, create one automatically. This means
287 	 * that we don't need a device tree node or platform data for the
288 	 * SPI flash chip - we will bind to the correct driver.
289 	 */
290 	if (ret == -ENODEV && drv_name) {
291 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
292 		      __func__, dev_name, busnum, cs, drv_name);
293 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
294 		if (ret)
295 			return ret;
296 		plat = dev_get_parent_platdata(dev);
297 		plat->cs = cs;
298 		plat->max_hz = speed;
299 		plat->mode = mode;
300 		created = true;
301 	} else if (ret) {
302 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
303 		       ret);
304 		return ret;
305 	}
306 
307 	if (!device_active(dev)) {
308 		struct spi_slave *slave;
309 
310 		ret = device_probe(dev);
311 		if (ret)
312 			goto err;
313 		slave = dev_get_parent_priv(dev);
314 		slave->dev = dev;
315 	}
316 
317 	plat = dev_get_parent_platdata(dev);
318 	if (!speed) {
319 		speed = plat->max_hz;
320 		mode = plat->mode;
321 	}
322 	ret = spi_set_speed_mode(bus, speed, mode);
323 	if (ret)
324 		goto err;
325 
326 	*busp = bus;
327 	*devp = dev_get_parent_priv(dev);
328 	debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
329 
330 	return 0;
331 
332 err:
333 	debug("%s: Error path, created=%d, device '%s'\n", __func__,
334 	      created, dev->name);
335 	if (created) {
336 		device_remove(dev);
337 		device_unbind(dev);
338 	}
339 
340 	return ret;
341 }
342 
343 /* Compatibility function - to be removed */
344 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
345 				      int bus_node)
346 {
347 	struct udevice *bus, *dev;
348 	int ret;
349 
350 	ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
351 	if (ret)
352 		return NULL;
353 	ret = device_get_child_by_of_offset(bus, node, &dev);
354 	if (ret)
355 		return NULL;
356 	return dev_get_parent_priv(dev);
357 }
358 
359 /* Compatibility function - to be removed */
360 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
361 				  unsigned int speed, unsigned int mode)
362 {
363 	struct spi_slave *slave;
364 	struct udevice *dev;
365 	int ret;
366 
367 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
368 				  &slave);
369 	if (ret)
370 		return NULL;
371 
372 	return slave;
373 }
374 
375 void spi_free_slave(struct spi_slave *slave)
376 {
377 	device_remove(slave->dev);
378 	slave->dev = NULL;
379 }
380 
381 int spi_slave_ofdata_to_platdata(const void *blob, int node,
382 				 struct dm_spi_slave_platdata *plat)
383 {
384 	int mode = 0, mode_rx = 0;
385 	int value;
386 
387 	plat->cs = fdtdec_get_int(blob, node, "reg", -1);
388 	plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
389 	if (fdtdec_get_bool(blob, node, "spi-cpol"))
390 		mode |= SPI_CPOL;
391 	if (fdtdec_get_bool(blob, node, "spi-cpha"))
392 		mode |= SPI_CPHA;
393 	if (fdtdec_get_bool(blob, node, "spi-cs-high"))
394 		mode |= SPI_CS_HIGH;
395 	if (fdtdec_get_bool(blob, node, "spi-3wire"))
396 		mode |= SPI_3WIRE;
397 	if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
398 		mode |= SPI_PREAMBLE;
399 
400 	/* Device DUAL/QUAD mode */
401 	value = fdtdec_get_uint(blob, node, "spi-tx-bus-width", 1);
402 	switch (value) {
403 	case 1:
404 		break;
405 	case 2:
406 		mode |= SPI_TX_DUAL;
407 		break;
408 	case 4:
409 		mode |= SPI_TX_QUAD;
410 		break;
411 	default:
412 		error("spi-tx-bus-width %d not supported\n", value);
413 		break;
414 	}
415 
416 	plat->mode = mode;
417 
418 	value = fdtdec_get_uint(blob, node, "spi-rx-bus-width", 1);
419 	switch (value) {
420 	case 1:
421 		break;
422 	case 2:
423 		mode_rx |= SPI_RX_DUAL;
424 		break;
425 	case 4:
426 		mode_rx |= SPI_RX_QUAD;
427 		break;
428 	default:
429 		error("spi-rx-bus-width %d not supported\n", value);
430 		break;
431 	}
432 
433 	plat->mode_rx = mode_rx;
434 
435 	return 0;
436 }
437 
438 UCLASS_DRIVER(spi) = {
439 	.id		= UCLASS_SPI,
440 	.name		= "spi",
441 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
442 	.post_bind	= dm_scan_fdt_dev,
443 	.post_probe	= spi_post_probe,
444 	.child_pre_probe = spi_child_pre_probe,
445 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
446 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
447 	.per_child_platdata_auto_alloc_size =
448 			sizeof(struct dm_spi_slave_platdata),
449 	.child_post_bind = spi_child_post_bind,
450 };
451 
452 UCLASS_DRIVER(spi_generic) = {
453 	.id		= UCLASS_SPI_GENERIC,
454 	.name		= "spi_generic",
455 };
456 
457 U_BOOT_DRIVER(spi_generic_drv) = {
458 	.name		= "spi_generic_drv",
459 	.id		= UCLASS_SPI_GENERIC,
460 };
461