xref: /openbmc/u-boot/drivers/spi/spi-uclass.c (revision baefb63a)
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 <malloc.h>
11 #include <spi.h>
12 #include <dm/device-internal.h>
13 #include <dm/uclass-internal.h>
14 #include <dm/lists.h>
15 #include <dm/util.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
20 {
21 	struct dm_spi_ops *ops;
22 	int ret;
23 
24 	ops = spi_get_ops(bus);
25 	if (ops->set_speed)
26 		ret = ops->set_speed(bus, speed);
27 	else
28 		ret = -EINVAL;
29 	if (ret) {
30 		printf("Cannot set speed (err=%d)\n", ret);
31 		return ret;
32 	}
33 
34 	if (ops->set_mode)
35 		ret = ops->set_mode(bus, mode);
36 	else
37 		ret = -EINVAL;
38 	if (ret) {
39 		printf("Cannot set mode (err=%d)\n", ret);
40 		return ret;
41 	}
42 
43 	return 0;
44 }
45 
46 int dm_spi_claim_bus(struct udevice *dev)
47 {
48 	struct udevice *bus = dev->parent;
49 	struct dm_spi_ops *ops = spi_get_ops(bus);
50 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
51 	struct spi_slave *slave = dev_get_parent_priv(dev);
52 	int speed;
53 	int ret;
54 
55 	speed = slave->max_hz;
56 	if (spi->max_hz) {
57 		if (speed)
58 			speed = min(speed, (int)spi->max_hz);
59 		else
60 			speed = spi->max_hz;
61 	}
62 	if (!speed)
63 		speed = 100000;
64 	if (speed != slave->speed) {
65 		ret = spi_set_speed_mode(bus, speed, slave->mode);
66 		if (ret)
67 			return ret;
68 		slave->speed = speed;
69 	}
70 
71 	return ops->claim_bus ? ops->claim_bus(dev) : 0;
72 }
73 
74 void dm_spi_release_bus(struct udevice *dev)
75 {
76 	struct udevice *bus = dev->parent;
77 	struct dm_spi_ops *ops = spi_get_ops(bus);
78 
79 	if (ops->release_bus)
80 		ops->release_bus(dev);
81 }
82 
83 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
84 		const void *dout, void *din, unsigned long flags)
85 {
86 	struct udevice *bus = dev->parent;
87 
88 	if (bus->uclass->uc_drv->id != UCLASS_SPI)
89 		return -EOPNOTSUPP;
90 
91 	return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
92 }
93 
94 int spi_claim_bus(struct spi_slave *slave)
95 {
96 	return dm_spi_claim_bus(slave->dev);
97 }
98 
99 void spi_release_bus(struct spi_slave *slave)
100 {
101 	dm_spi_release_bus(slave->dev);
102 }
103 
104 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
105 	     const void *dout, void *din, unsigned long flags)
106 {
107 	return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
108 }
109 
110 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
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_valid(dev))
116 		return 0;
117 
118 	return spi_slave_ofdata_to_platdata(dev, plat);
119 }
120 #endif
121 
122 static int spi_post_probe(struct udevice *bus)
123 {
124 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
125 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
126 
127 	spi->max_hz = dev_read_u32_default(bus, "spi-max-frequency", 0);
128 #endif
129 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
130 	struct dm_spi_ops *ops = spi_get_ops(bus);
131 
132 
133 	if (ops->claim_bus)
134 		ops->claim_bus += gd->reloc_off;
135 	if (ops->release_bus)
136 		ops->release_bus += gd->reloc_off;
137 	if (ops->set_wordlen)
138 		ops->set_wordlen += gd->reloc_off;
139 	if (ops->xfer)
140 		ops->xfer += gd->reloc_off;
141 	if (ops->set_speed)
142 		ops->set_speed += gd->reloc_off;
143 	if (ops->set_mode)
144 		ops->set_mode += gd->reloc_off;
145 	if (ops->cs_info)
146 		ops->cs_info += gd->reloc_off;
147 #endif
148 
149 	return 0;
150 }
151 
152 static int spi_child_pre_probe(struct udevice *dev)
153 {
154 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
155 	struct spi_slave *slave = dev_get_parent_priv(dev);
156 
157 	/*
158 	 * This is needed because we pass struct spi_slave around the place
159 	 * instead slave->dev (a struct udevice). So we have to have some
160 	 * way to access the slave udevice given struct spi_slave. Once we
161 	 * change the SPI API to use udevice instead of spi_slave, we can
162 	 * drop this.
163 	 */
164 	slave->dev = dev;
165 
166 	slave->max_hz = plat->max_hz;
167 	slave->mode = plat->mode;
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 #if CONFIG_IS_ENABLED(OF_PLATDATA)
279 	ret = uclass_first_device_err(UCLASS_SPI, &bus);
280 #else
281 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
282 #endif
283 	if (ret) {
284 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
285 		return ret;
286 	}
287 	ret = spi_find_chip_select(bus, cs, &dev);
288 
289 	/*
290 	 * If there is no such device, create one automatically. This means
291 	 * that we don't need a device tree node or platform data for the
292 	 * SPI flash chip - we will bind to the correct driver.
293 	 */
294 	if (ret == -ENODEV && drv_name) {
295 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
296 		      __func__, dev_name, busnum, cs, drv_name);
297 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
298 		if (ret) {
299 			debug("%s: Unable to bind driver (ret=%d)\n", __func__,
300 			      ret);
301 			return ret;
302 		}
303 		plat = dev_get_parent_platdata(dev);
304 		plat->cs = cs;
305 		plat->max_hz = speed;
306 		plat->mode = mode;
307 		created = true;
308 	} else if (ret) {
309 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
310 		       ret);
311 		return ret;
312 	}
313 
314 	if (!device_active(dev)) {
315 		struct spi_slave *slave;
316 
317 		ret = device_probe(dev);
318 		if (ret)
319 			goto err;
320 		slave = dev_get_parent_priv(dev);
321 		slave->dev = dev;
322 	}
323 
324 	plat = dev_get_parent_platdata(dev);
325 	if (!speed) {
326 		speed = plat->max_hz;
327 		mode = plat->mode;
328 	}
329 	ret = spi_set_speed_mode(bus, speed, mode);
330 	if (ret)
331 		goto err;
332 
333 	*busp = bus;
334 	*devp = dev_get_parent_priv(dev);
335 	debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
336 
337 	return 0;
338 
339 err:
340 	debug("%s: Error path, created=%d, device '%s'\n", __func__,
341 	      created, dev->name);
342 	if (created) {
343 		device_remove(dev, DM_REMOVE_NORMAL);
344 		device_unbind(dev);
345 	}
346 
347 	return ret;
348 }
349 
350 /* Compatibility function - to be removed */
351 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
352 				      int bus_node)
353 {
354 	struct udevice *bus, *dev;
355 	int ret;
356 
357 	ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
358 	if (ret)
359 		return NULL;
360 	ret = device_get_child_by_of_offset(bus, node, &dev);
361 	if (ret)
362 		return NULL;
363 	return dev_get_parent_priv(dev);
364 }
365 
366 /* Compatibility function - to be removed */
367 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
368 				  unsigned int speed, unsigned int mode)
369 {
370 	struct spi_slave *slave;
371 	struct udevice *dev;
372 	int ret;
373 
374 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
375 				 &slave);
376 	if (ret)
377 		return NULL;
378 
379 	return slave;
380 }
381 
382 void spi_free_slave(struct spi_slave *slave)
383 {
384 	device_remove(slave->dev, DM_REMOVE_NORMAL);
385 	slave->dev = NULL;
386 }
387 
388 int spi_slave_ofdata_to_platdata(struct udevice *dev,
389 				 struct dm_spi_slave_platdata *plat)
390 {
391 	int mode = 0;
392 	int value;
393 
394 	plat->cs = dev_read_u32_default(dev, "reg", -1);
395 	plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency", 0);
396 	if (dev_read_bool(dev, "spi-cpol"))
397 		mode |= SPI_CPOL;
398 	if (dev_read_bool(dev, "spi-cpha"))
399 		mode |= SPI_CPHA;
400 	if (dev_read_bool(dev, "spi-cs-high"))
401 		mode |= SPI_CS_HIGH;
402 	if (dev_read_bool(dev, "spi-3wire"))
403 		mode |= SPI_3WIRE;
404 	if (dev_read_bool(dev, "spi-half-duplex"))
405 		mode |= SPI_PREAMBLE;
406 
407 	/* Device DUAL/QUAD mode */
408 	value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
409 	switch (value) {
410 	case 1:
411 		break;
412 	case 2:
413 		mode |= SPI_TX_DUAL;
414 		break;
415 	case 4:
416 		mode |= SPI_TX_QUAD;
417 		break;
418 	default:
419 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
420 		break;
421 	}
422 
423 	value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
424 	switch (value) {
425 	case 1:
426 		break;
427 	case 2:
428 		mode |= SPI_RX_DUAL;
429 		break;
430 	case 4:
431 		mode |= SPI_RX_QUAD;
432 		break;
433 	default:
434 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
435 		break;
436 	}
437 
438 	plat->mode = mode;
439 
440 	return 0;
441 }
442 
443 UCLASS_DRIVER(spi) = {
444 	.id		= UCLASS_SPI,
445 	.name		= "spi",
446 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
447 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
448 	.post_bind	= dm_scan_fdt_dev,
449 #endif
450 	.post_probe	= spi_post_probe,
451 	.child_pre_probe = spi_child_pre_probe,
452 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
453 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
454 	.per_child_platdata_auto_alloc_size =
455 			sizeof(struct dm_spi_slave_platdata),
456 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
457 	.child_post_bind = spi_child_post_bind,
458 #endif
459 };
460 
461 UCLASS_DRIVER(spi_generic) = {
462 	.id		= UCLASS_SPI_GENERIC,
463 	.name		= "spi_generic",
464 };
465 
466 U_BOOT_DRIVER(spi_generic_drv) = {
467 	.name		= "spi_generic_drv",
468 	.id		= UCLASS_SPI_GENERIC,
469 };
470