xref: /openbmc/u-boot/drivers/spi/spi-uclass.c (revision be059e88)
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 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
112 static int spi_child_post_bind(struct udevice *dev)
113 {
114 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
115 
116 	if (dev->of_offset == -1)
117 		return 0;
118 
119 	return spi_slave_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, plat);
120 }
121 #endif
122 
123 static int spi_post_probe(struct udevice *bus)
124 {
125 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
126 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
127 
128 	spi->max_hz = fdtdec_get_int(gd->fdt_blob, bus->of_offset,
129 				     "spi-max-frequency", 0);
130 #endif
131 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
132 	struct dm_spi_ops *ops = spi_get_ops(bus);
133 
134 
135 	if (ops->claim_bus)
136 		ops->claim_bus += gd->reloc_off;
137 	if (ops->release_bus)
138 		ops->release_bus += gd->reloc_off;
139 	if (ops->set_wordlen)
140 		ops->set_wordlen += gd->reloc_off;
141 	if (ops->xfer)
142 		ops->xfer += gd->reloc_off;
143 	if (ops->set_speed)
144 		ops->set_speed += gd->reloc_off;
145 	if (ops->set_mode)
146 		ops->set_mode += gd->reloc_off;
147 	if (ops->cs_info)
148 		ops->cs_info += gd->reloc_off;
149 #endif
150 
151 	return 0;
152 }
153 
154 static int spi_child_pre_probe(struct udevice *dev)
155 {
156 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
157 	struct spi_slave *slave = dev_get_parent_priv(dev);
158 
159 	/*
160 	 * This is needed because we pass struct spi_slave around the place
161 	 * instead slave->dev (a struct udevice). So we have to have some
162 	 * way to access the slave udevice given struct spi_slave. Once we
163 	 * change the SPI API to use udevice instead of spi_slave, we can
164 	 * drop this.
165 	 */
166 	slave->dev = dev;
167 
168 	slave->max_hz = plat->max_hz;
169 	slave->mode = plat->mode;
170 	slave->wordlen = SPI_DEFAULT_WORDLEN;
171 
172 	return 0;
173 }
174 
175 int spi_chip_select(struct udevice *dev)
176 {
177 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
178 
179 	return plat ? plat->cs : -ENOENT;
180 }
181 
182 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
183 {
184 	struct udevice *dev;
185 
186 	for (device_find_first_child(bus, &dev); dev;
187 	     device_find_next_child(&dev)) {
188 		struct dm_spi_slave_platdata *plat;
189 
190 		plat = dev_get_parent_platdata(dev);
191 		debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
192 		if (plat->cs == cs) {
193 			*devp = dev;
194 			return 0;
195 		}
196 	}
197 
198 	return -ENODEV;
199 }
200 
201 int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
202 {
203 	struct spi_cs_info info;
204 	struct udevice *bus;
205 	int ret;
206 
207 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
208 	if (ret) {
209 		debug("%s: No bus %d\n", __func__, busnum);
210 		return ret;
211 	}
212 
213 	return spi_cs_info(bus, cs, &info);
214 }
215 
216 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
217 {
218 	struct spi_cs_info local_info;
219 	struct dm_spi_ops *ops;
220 	int ret;
221 
222 	if (!info)
223 		info = &local_info;
224 
225 	/* If there is a device attached, return it */
226 	info->dev = NULL;
227 	ret = spi_find_chip_select(bus, cs, &info->dev);
228 	if (!ret)
229 		return 0;
230 
231 	/*
232 	 * Otherwise ask the driver. For the moment we don't have CS info.
233 	 * When we do we could provide the driver with a helper function
234 	 * to figure out what chip selects are valid, or just handle the
235 	 * request.
236 	 */
237 	ops = spi_get_ops(bus);
238 	if (ops->cs_info)
239 		return ops->cs_info(bus, cs, info);
240 
241 	/*
242 	 * We could assume there is at least one valid chip select, but best
243 	 * to be sure and return an error in this case. The driver didn't
244 	 * care enough to tell us.
245 	 */
246 	return -ENODEV;
247 }
248 
249 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
250 			struct udevice **devp)
251 {
252 	struct udevice *bus, *dev;
253 	int ret;
254 
255 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
256 	if (ret) {
257 		debug("%s: No bus %d\n", __func__, busnum);
258 		return ret;
259 	}
260 	ret = spi_find_chip_select(bus, cs, &dev);
261 	if (ret) {
262 		debug("%s: No cs %d\n", __func__, cs);
263 		return ret;
264 	}
265 	*busp = bus;
266 	*devp = dev;
267 
268 	return ret;
269 }
270 
271 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
272 		       const char *drv_name, const char *dev_name,
273 		       struct udevice **busp, struct spi_slave **devp)
274 {
275 	struct udevice *bus, *dev;
276 	struct dm_spi_slave_platdata *plat;
277 	bool created = false;
278 	int ret;
279 
280 #if CONFIG_IS_ENABLED(OF_PLATDATA)
281 	ret = uclass_first_device_err(UCLASS_SPI, &bus);
282 #else
283 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
284 #endif
285 	if (ret) {
286 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
287 		return ret;
288 	}
289 	ret = spi_find_chip_select(bus, cs, &dev);
290 
291 	/*
292 	 * If there is no such device, create one automatically. This means
293 	 * that we don't need a device tree node or platform data for the
294 	 * SPI flash chip - we will bind to the correct driver.
295 	 */
296 	if (ret == -ENODEV && drv_name) {
297 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
298 		      __func__, dev_name, busnum, cs, drv_name);
299 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
300 		if (ret) {
301 			debug("%s: Unable to bind driver (ret=%d)\n", __func__,
302 			      ret);
303 			return ret;
304 		}
305 		plat = dev_get_parent_platdata(dev);
306 		plat->cs = cs;
307 		plat->max_hz = speed;
308 		plat->mode = mode;
309 		created = true;
310 	} else if (ret) {
311 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
312 		       ret);
313 		return ret;
314 	}
315 
316 	if (!device_active(dev)) {
317 		struct spi_slave *slave;
318 
319 		ret = device_probe(dev);
320 		if (ret)
321 			goto err;
322 		slave = dev_get_parent_priv(dev);
323 		slave->dev = dev;
324 	}
325 
326 	plat = dev_get_parent_platdata(dev);
327 	if (!speed) {
328 		speed = plat->max_hz;
329 		mode = plat->mode;
330 	}
331 	ret = spi_set_speed_mode(bus, speed, mode);
332 	if (ret)
333 		goto err;
334 
335 	*busp = bus;
336 	*devp = dev_get_parent_priv(dev);
337 	debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
338 
339 	return 0;
340 
341 err:
342 	debug("%s: Error path, created=%d, device '%s'\n", __func__,
343 	      created, dev->name);
344 	if (created) {
345 		device_remove(dev);
346 		device_unbind(dev);
347 	}
348 
349 	return ret;
350 }
351 
352 /* Compatibility function - to be removed */
353 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
354 				      int bus_node)
355 {
356 	struct udevice *bus, *dev;
357 	int ret;
358 
359 	ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
360 	if (ret)
361 		return NULL;
362 	ret = device_get_child_by_of_offset(bus, node, &dev);
363 	if (ret)
364 		return NULL;
365 	return dev_get_parent_priv(dev);
366 }
367 
368 /* Compatibility function - to be removed */
369 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
370 				  unsigned int speed, unsigned int mode)
371 {
372 	struct spi_slave *slave;
373 	struct udevice *dev;
374 	int ret;
375 
376 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
377 				  &slave);
378 	if (ret)
379 		return NULL;
380 
381 	return slave;
382 }
383 
384 void spi_free_slave(struct spi_slave *slave)
385 {
386 	device_remove(slave->dev);
387 	slave->dev = NULL;
388 }
389 
390 int spi_slave_ofdata_to_platdata(const void *blob, int node,
391 				 struct dm_spi_slave_platdata *plat)
392 {
393 	int mode = 0;
394 	int value;
395 
396 	plat->cs = fdtdec_get_int(blob, node, "reg", -1);
397 	plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
398 	if (fdtdec_get_bool(blob, node, "spi-cpol"))
399 		mode |= SPI_CPOL;
400 	if (fdtdec_get_bool(blob, node, "spi-cpha"))
401 		mode |= SPI_CPHA;
402 	if (fdtdec_get_bool(blob, node, "spi-cs-high"))
403 		mode |= SPI_CS_HIGH;
404 	if (fdtdec_get_bool(blob, node, "spi-3wire"))
405 		mode |= SPI_3WIRE;
406 	if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
407 		mode |= SPI_PREAMBLE;
408 
409 	/* Device DUAL/QUAD mode */
410 	value = fdtdec_get_uint(blob, node, "spi-tx-bus-width", 1);
411 	switch (value) {
412 	case 1:
413 		break;
414 	case 2:
415 		mode |= SPI_TX_DUAL;
416 		break;
417 	case 4:
418 		mode |= SPI_TX_QUAD;
419 		break;
420 	default:
421 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
422 		break;
423 	}
424 
425 	value = fdtdec_get_uint(blob, node, "spi-rx-bus-width", 1);
426 	switch (value) {
427 	case 1:
428 		break;
429 	case 2:
430 		mode |= SPI_RX_DUAL;
431 		break;
432 	case 4:
433 		mode |= SPI_RX_QUAD;
434 		break;
435 	default:
436 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
437 		break;
438 	}
439 
440 	plat->mode = mode;
441 
442 	return 0;
443 }
444 
445 UCLASS_DRIVER(spi) = {
446 	.id		= UCLASS_SPI,
447 	.name		= "spi",
448 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
449 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
450 	.post_bind	= dm_scan_fdt_dev,
451 #endif
452 	.post_probe	= spi_post_probe,
453 	.child_pre_probe = spi_child_pre_probe,
454 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
455 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
456 	.per_child_platdata_auto_alloc_size =
457 			sizeof(struct dm_spi_slave_platdata),
458 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
459 	.child_post_bind = spi_child_post_bind,
460 #endif
461 };
462 
463 UCLASS_DRIVER(spi_generic) = {
464 	.id		= UCLASS_SPI_GENERIC,
465 	.name		= "spi_generic",
466 };
467 
468 U_BOOT_DRIVER(spi_generic_drv) = {
469 	.name		= "spi_generic_drv",
470 	.id		= UCLASS_SPI_GENERIC,
471 };
472