xref: /openbmc/u-boot/drivers/spi/spi-uclass.c (revision 0093b3fc)
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 
54 	speed = slave->max_hz;
55 	if (spi->max_hz) {
56 		if (speed)
57 			speed = min(speed, (int)spi->max_hz);
58 		else
59 			speed = spi->max_hz;
60 	}
61 	if (!speed)
62 		speed = 100000;
63 	if (speed != slave->speed) {
64 		int ret = spi_set_speed_mode(bus, speed, slave->mode);
65 
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 	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->wordlen = SPI_DEFAULT_WORDLEN;
168 
169 	return 0;
170 }
171 
172 int spi_chip_select(struct udevice *dev)
173 {
174 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
175 
176 	return plat ? plat->cs : -ENOENT;
177 }
178 
179 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
180 {
181 	struct udevice *dev;
182 
183 	for (device_find_first_child(bus, &dev); dev;
184 	     device_find_next_child(&dev)) {
185 		struct dm_spi_slave_platdata *plat;
186 
187 		plat = dev_get_parent_platdata(dev);
188 		debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
189 		if (plat->cs == cs) {
190 			*devp = dev;
191 			return 0;
192 		}
193 	}
194 
195 	return -ENODEV;
196 }
197 
198 int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
199 {
200 	struct spi_cs_info info;
201 	struct udevice *bus;
202 	int ret;
203 
204 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
205 	if (ret) {
206 		debug("%s: No bus %d\n", __func__, busnum);
207 		return ret;
208 	}
209 
210 	return spi_cs_info(bus, cs, &info);
211 }
212 
213 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
214 {
215 	struct spi_cs_info local_info;
216 	struct dm_spi_ops *ops;
217 	int ret;
218 
219 	if (!info)
220 		info = &local_info;
221 
222 	/* If there is a device attached, return it */
223 	info->dev = NULL;
224 	ret = spi_find_chip_select(bus, cs, &info->dev);
225 	if (!ret)
226 		return 0;
227 
228 	/*
229 	 * Otherwise ask the driver. For the moment we don't have CS info.
230 	 * When we do we could provide the driver with a helper function
231 	 * to figure out what chip selects are valid, or just handle the
232 	 * request.
233 	 */
234 	ops = spi_get_ops(bus);
235 	if (ops->cs_info)
236 		return ops->cs_info(bus, cs, info);
237 
238 	/*
239 	 * We could assume there is at least one valid chip select, but best
240 	 * to be sure and return an error in this case. The driver didn't
241 	 * care enough to tell us.
242 	 */
243 	return -ENODEV;
244 }
245 
246 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
247 			struct udevice **devp)
248 {
249 	struct udevice *bus, *dev;
250 	int ret;
251 
252 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
253 	if (ret) {
254 		debug("%s: No bus %d\n", __func__, busnum);
255 		return ret;
256 	}
257 	ret = spi_find_chip_select(bus, cs, &dev);
258 	if (ret) {
259 		debug("%s: No cs %d\n", __func__, cs);
260 		return ret;
261 	}
262 	*busp = bus;
263 	*devp = dev;
264 
265 	return ret;
266 }
267 
268 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
269 		       const char *drv_name, const char *dev_name,
270 		       struct udevice **busp, struct spi_slave **devp)
271 {
272 	struct udevice *bus, *dev;
273 	struct dm_spi_slave_platdata *plat;
274 	bool created = false;
275 	int ret;
276 
277 #if CONFIG_IS_ENABLED(OF_PLATDATA)
278 	ret = uclass_first_device_err(UCLASS_SPI, &bus);
279 #else
280 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
281 #endif
282 	if (ret) {
283 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
284 		return ret;
285 	}
286 	ret = spi_find_chip_select(bus, cs, &dev);
287 
288 	/*
289 	 * If there is no such device, create one automatically. This means
290 	 * that we don't need a device tree node or platform data for the
291 	 * SPI flash chip - we will bind to the correct driver.
292 	 */
293 	if (ret == -ENODEV && drv_name) {
294 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
295 		      __func__, dev_name, busnum, cs, drv_name);
296 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
297 		if (ret) {
298 			debug("%s: Unable to bind driver (ret=%d)\n", __func__,
299 			      ret);
300 			return ret;
301 		}
302 		plat = dev_get_parent_platdata(dev);
303 		plat->cs = cs;
304 		plat->max_hz = speed;
305 		plat->mode = mode;
306 		created = true;
307 	} else if (ret) {
308 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
309 		       ret);
310 		return ret;
311 	}
312 
313 	if (!device_active(dev)) {
314 		struct spi_slave *slave;
315 
316 		ret = device_probe(dev);
317 		if (ret)
318 			goto err;
319 		slave = dev_get_parent_priv(dev);
320 		slave->dev = dev;
321 	}
322 
323 	plat = dev_get_parent_platdata(dev);
324 	if (!speed) {
325 		speed = plat->max_hz;
326 		mode = plat->mode;
327 	}
328 	ret = spi_set_speed_mode(bus, speed, mode);
329 	if (ret)
330 		goto err;
331 
332 	*busp = bus;
333 	*devp = dev_get_parent_priv(dev);
334 	debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
335 
336 	return 0;
337 
338 err:
339 	debug("%s: Error path, created=%d, device '%s'\n", __func__,
340 	      created, dev->name);
341 	if (created) {
342 		device_remove(dev, DM_REMOVE_NORMAL);
343 		device_unbind(dev);
344 	}
345 
346 	return ret;
347 }
348 
349 /* Compatibility function - to be removed */
350 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
351 				  unsigned int speed, unsigned int mode)
352 {
353 	struct spi_slave *slave;
354 	struct udevice *dev;
355 	int ret;
356 
357 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
358 				 &slave);
359 	if (ret)
360 		return NULL;
361 
362 	return slave;
363 }
364 
365 void spi_free_slave(struct spi_slave *slave)
366 {
367 	device_remove(slave->dev, DM_REMOVE_NORMAL);
368 	slave->dev = NULL;
369 }
370 
371 int spi_slave_ofdata_to_platdata(struct udevice *dev,
372 				 struct dm_spi_slave_platdata *plat)
373 {
374 	int mode = 0;
375 	int value;
376 
377 	plat->cs = dev_read_u32_default(dev, "reg", -1);
378 	plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency", 0);
379 	if (dev_read_bool(dev, "spi-cpol"))
380 		mode |= SPI_CPOL;
381 	if (dev_read_bool(dev, "spi-cpha"))
382 		mode |= SPI_CPHA;
383 	if (dev_read_bool(dev, "spi-cs-high"))
384 		mode |= SPI_CS_HIGH;
385 	if (dev_read_bool(dev, "spi-3wire"))
386 		mode |= SPI_3WIRE;
387 	if (dev_read_bool(dev, "spi-half-duplex"))
388 		mode |= SPI_PREAMBLE;
389 
390 	/* Device DUAL/QUAD mode */
391 	value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
392 	switch (value) {
393 	case 1:
394 		break;
395 	case 2:
396 		mode |= SPI_TX_DUAL;
397 		break;
398 	case 4:
399 		mode |= SPI_TX_QUAD;
400 		break;
401 	default:
402 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
403 		break;
404 	}
405 
406 	value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
407 	switch (value) {
408 	case 1:
409 		break;
410 	case 2:
411 		mode |= SPI_RX_DUAL;
412 		break;
413 	case 4:
414 		mode |= SPI_RX_QUAD;
415 		break;
416 	default:
417 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
418 		break;
419 	}
420 
421 	plat->mode = mode;
422 
423 	return 0;
424 }
425 
426 UCLASS_DRIVER(spi) = {
427 	.id		= UCLASS_SPI,
428 	.name		= "spi",
429 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
430 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
431 	.post_bind	= dm_scan_fdt_dev,
432 #endif
433 	.post_probe	= spi_post_probe,
434 	.child_pre_probe = spi_child_pre_probe,
435 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
436 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
437 	.per_child_platdata_auto_alloc_size =
438 			sizeof(struct dm_spi_slave_platdata),
439 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
440 	.child_post_bind = spi_child_post_bind,
441 #endif
442 };
443 
444 UCLASS_DRIVER(spi_generic) = {
445 	.id		= UCLASS_SPI_GENERIC,
446 	.name		= "spi_generic",
447 };
448 
449 U_BOOT_DRIVER(spi_generic_drv) = {
450 	.name		= "spi_generic_drv",
451 	.id		= UCLASS_SPI_GENERIC,
452 };
453