xref: /openbmc/u-boot/drivers/spi/spi-uclass.c (revision 44093a15)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2014 Google, Inc
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <malloc.h>
10 #include <spi.h>
11 #include <dm/device-internal.h>
12 #include <dm/uclass-internal.h>
13 #include <dm/lists.h>
14 #include <dm/util.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
19 {
20 	struct dm_spi_ops *ops;
21 	int ret;
22 
23 	ops = spi_get_ops(bus);
24 	if (ops->set_speed)
25 		ret = ops->set_speed(bus, speed);
26 	else
27 		ret = -EINVAL;
28 	if (ret) {
29 		printf("Cannot set speed (err=%d)\n", ret);
30 		return ret;
31 	}
32 
33 	if (ops->set_mode)
34 		ret = ops->set_mode(bus, mode);
35 	else
36 		ret = -EINVAL;
37 	if (ret) {
38 		printf("Cannot set mode (err=%d)\n", ret);
39 		return ret;
40 	}
41 
42 	return 0;
43 }
44 
45 int dm_spi_claim_bus(struct udevice *dev)
46 {
47 	struct udevice *bus = dev->parent;
48 	struct dm_spi_ops *ops = spi_get_ops(bus);
49 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
50 	struct spi_slave *slave = dev_get_parent_priv(dev);
51 	int speed;
52 
53 	speed = slave->max_hz;
54 	if (spi->max_hz) {
55 		if (speed)
56 			speed = min(speed, (int)spi->max_hz);
57 		else
58 			speed = spi->max_hz;
59 	}
60 	if (!speed)
61 		speed = 100000;
62 	if (speed != slave->speed) {
63 		int ret = spi_set_speed_mode(bus, speed, slave->mode);
64 
65 		if (ret)
66 			return log_ret(ret);
67 		slave->speed = speed;
68 	}
69 
70 	return log_ret(ops->claim_bus ? ops->claim_bus(dev) : 0);
71 }
72 
73 void dm_spi_release_bus(struct udevice *dev)
74 {
75 	struct udevice *bus = dev->parent;
76 	struct dm_spi_ops *ops = spi_get_ops(bus);
77 
78 	if (ops->release_bus)
79 		ops->release_bus(dev);
80 }
81 
82 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
83 		const void *dout, void *din, unsigned long flags)
84 {
85 	struct udevice *bus = dev->parent;
86 
87 	if (bus->uclass->uc_drv->id != UCLASS_SPI)
88 		return -EOPNOTSUPP;
89 
90 	return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
91 }
92 
93 int spi_claim_bus(struct spi_slave *slave)
94 {
95 	return log_ret(dm_spi_claim_bus(slave->dev));
96 }
97 
98 void spi_release_bus(struct spi_slave *slave)
99 {
100 	dm_spi_release_bus(slave->dev);
101 }
102 
103 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
104 	     const void *dout, void *din, unsigned long flags)
105 {
106 	return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
107 }
108 
109 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
110 static int spi_child_post_bind(struct udevice *dev)
111 {
112 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
113 
114 	if (!dev_of_valid(dev))
115 		return 0;
116 
117 	return spi_slave_ofdata_to_platdata(dev, plat);
118 }
119 #endif
120 
121 static int spi_post_probe(struct udevice *bus)
122 {
123 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
124 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
125 
126 	spi->max_hz = dev_read_u32_default(bus, "spi-max-frequency", 0);
127 #endif
128 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
129 	struct dm_spi_ops *ops = spi_get_ops(bus);
130 
131 	if (ops->claim_bus)
132 		ops->claim_bus += gd->reloc_off;
133 	if (ops->release_bus)
134 		ops->release_bus += gd->reloc_off;
135 	if (ops->set_wordlen)
136 		ops->set_wordlen += gd->reloc_off;
137 	if (ops->xfer)
138 		ops->xfer += gd->reloc_off;
139 	if (ops->set_speed)
140 		ops->set_speed += gd->reloc_off;
141 	if (ops->set_mode)
142 		ops->set_mode += gd->reloc_off;
143 	if (ops->cs_info)
144 		ops->cs_info += gd->reloc_off;
145 #endif
146 
147 	return 0;
148 }
149 
150 static int spi_child_pre_probe(struct udevice *dev)
151 {
152 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
153 	struct spi_slave *slave = dev_get_parent_priv(dev);
154 
155 	/*
156 	 * This is needed because we pass struct spi_slave around the place
157 	 * instead slave->dev (a struct udevice). So we have to have some
158 	 * way to access the slave udevice given struct spi_slave. Once we
159 	 * change the SPI API to use udevice instead of spi_slave, we can
160 	 * drop this.
161 	 */
162 	slave->dev = dev;
163 
164 	slave->max_hz = plat->max_hz;
165 	slave->mode = plat->mode;
166 	slave->wordlen = SPI_DEFAULT_WORDLEN;
167 
168 	return 0;
169 }
170 
171 int spi_chip_select(struct udevice *dev)
172 {
173 	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
174 
175 	return plat ? plat->cs : -ENOENT;
176 }
177 
178 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
179 {
180 	struct udevice *dev;
181 
182 	for (device_find_first_child(bus, &dev); dev;
183 	     device_find_next_child(&dev)) {
184 		struct dm_spi_slave_platdata *plat;
185 
186 		plat = dev_get_parent_platdata(dev);
187 		debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
188 		if (plat->cs == cs) {
189 			*devp = dev;
190 			return 0;
191 		}
192 	}
193 
194 	return -ENODEV;
195 }
196 
197 int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
198 {
199 	struct spi_cs_info info;
200 	struct udevice *bus;
201 	int ret;
202 
203 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
204 	if (ret) {
205 		debug("%s: No bus %d\n", __func__, busnum);
206 		return ret;
207 	}
208 
209 	return spi_cs_info(bus, cs, &info);
210 }
211 
212 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
213 {
214 	struct spi_cs_info local_info;
215 	struct dm_spi_ops *ops;
216 	int ret;
217 
218 	if (!info)
219 		info = &local_info;
220 
221 	/* If there is a device attached, return it */
222 	info->dev = NULL;
223 	ret = spi_find_chip_select(bus, cs, &info->dev);
224 	if (!ret)
225 		return 0;
226 
227 	/*
228 	 * Otherwise ask the driver. For the moment we don't have CS info.
229 	 * When we do we could provide the driver with a helper function
230 	 * to figure out what chip selects are valid, or just handle the
231 	 * request.
232 	 */
233 	ops = spi_get_ops(bus);
234 	if (ops->cs_info)
235 		return ops->cs_info(bus, cs, info);
236 
237 	/*
238 	 * We could assume there is at least one valid chip select, but best
239 	 * to be sure and return an error in this case. The driver didn't
240 	 * care enough to tell us.
241 	 */
242 	return -ENODEV;
243 }
244 
245 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
246 			struct udevice **devp)
247 {
248 	struct udevice *bus, *dev;
249 	int ret;
250 
251 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
252 	if (ret) {
253 		debug("%s: No bus %d\n", __func__, busnum);
254 		return ret;
255 	}
256 	ret = spi_find_chip_select(bus, cs, &dev);
257 	if (ret) {
258 		debug("%s: No cs %d\n", __func__, cs);
259 		return ret;
260 	}
261 	*busp = bus;
262 	*devp = dev;
263 
264 	return ret;
265 }
266 
267 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
268 		       const char *drv_name, const char *dev_name,
269 		       struct udevice **busp, struct spi_slave **devp)
270 {
271 	struct udevice *bus, *dev;
272 	struct dm_spi_slave_platdata *plat;
273 	bool created = false;
274 	int ret;
275 
276 #if CONFIG_IS_ENABLED(OF_PLATDATA) || CONFIG_IS_ENABLED(OF_PRIOR_STAGE)
277 	ret = uclass_first_device_err(UCLASS_SPI, &bus);
278 #else
279 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
280 #endif
281 	if (ret) {
282 		printf("Invalid bus %d (err=%d)\n", busnum, ret);
283 		return ret;
284 	}
285 	ret = spi_find_chip_select(bus, cs, &dev);
286 
287 	/*
288 	 * If there is no such device, create one automatically. This means
289 	 * that we don't need a device tree node or platform data for the
290 	 * SPI flash chip - we will bind to the correct driver.
291 	 */
292 	if (ret == -ENODEV && drv_name) {
293 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
294 		      __func__, dev_name, busnum, cs, drv_name);
295 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
296 		if (ret) {
297 			debug("%s: Unable to bind driver (ret=%d)\n", __func__,
298 			      ret);
299 			return ret;
300 		}
301 		plat = dev_get_parent_platdata(dev);
302 		plat->cs = cs;
303 		plat->max_hz = speed;
304 		plat->mode = mode;
305 		created = true;
306 	} else if (ret) {
307 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
308 		       ret);
309 		return ret;
310 	}
311 
312 	if (!device_active(dev)) {
313 		struct spi_slave *slave;
314 
315 		ret = device_probe(dev);
316 		if (ret)
317 			goto err;
318 		slave = dev_get_parent_priv(dev);
319 		slave->dev = dev;
320 	}
321 
322 	plat = dev_get_parent_platdata(dev);
323 	if (!speed) {
324 		speed = plat->max_hz;
325 		mode = plat->mode;
326 	}
327 	ret = spi_set_speed_mode(bus, speed, mode);
328 	if (ret)
329 		goto err;
330 
331 	*busp = bus;
332 	*devp = dev_get_parent_priv(dev);
333 	debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
334 
335 	return 0;
336 
337 err:
338 	debug("%s: Error path, created=%d, device '%s'\n", __func__,
339 	      created, dev->name);
340 	if (created) {
341 		device_remove(dev, DM_REMOVE_NORMAL);
342 		device_unbind(dev);
343 	}
344 
345 	return ret;
346 }
347 
348 /* Compatibility function - to be removed */
349 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
350 				  unsigned int speed, unsigned int mode)
351 {
352 	struct spi_slave *slave;
353 	struct udevice *dev;
354 	int ret;
355 
356 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
357 				 &slave);
358 	if (ret)
359 		return NULL;
360 
361 	return slave;
362 }
363 
364 void spi_free_slave(struct spi_slave *slave)
365 {
366 	device_remove(slave->dev, DM_REMOVE_NORMAL);
367 	slave->dev = NULL;
368 }
369 
370 int spi_slave_ofdata_to_platdata(struct udevice *dev,
371 				 struct dm_spi_slave_platdata *plat)
372 {
373 	int mode = 0;
374 	int value;
375 
376 	plat->cs = dev_read_u32_default(dev, "reg", -1);
377 	plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency", 0);
378 	if (dev_read_bool(dev, "spi-cpol"))
379 		mode |= SPI_CPOL;
380 	if (dev_read_bool(dev, "spi-cpha"))
381 		mode |= SPI_CPHA;
382 	if (dev_read_bool(dev, "spi-cs-high"))
383 		mode |= SPI_CS_HIGH;
384 	if (dev_read_bool(dev, "spi-3wire"))
385 		mode |= SPI_3WIRE;
386 	if (dev_read_bool(dev, "spi-half-duplex"))
387 		mode |= SPI_PREAMBLE;
388 
389 	/* Device DUAL/QUAD mode */
390 	value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
391 	switch (value) {
392 	case 1:
393 		break;
394 	case 2:
395 		mode |= SPI_TX_DUAL;
396 		break;
397 	case 4:
398 		mode |= SPI_TX_QUAD;
399 		break;
400 	default:
401 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
402 		break;
403 	}
404 
405 	value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
406 	switch (value) {
407 	case 1:
408 		break;
409 	case 2:
410 		mode |= SPI_RX_DUAL;
411 		break;
412 	case 4:
413 		mode |= SPI_RX_QUAD;
414 		break;
415 	default:
416 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
417 		break;
418 	}
419 
420 	plat->mode = mode;
421 
422 	return 0;
423 }
424 
425 UCLASS_DRIVER(spi) = {
426 	.id		= UCLASS_SPI,
427 	.name		= "spi",
428 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
429 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
430 	.post_bind	= dm_scan_fdt_dev,
431 #endif
432 	.post_probe	= spi_post_probe,
433 	.child_pre_probe = spi_child_pre_probe,
434 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
435 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
436 	.per_child_platdata_auto_alloc_size =
437 			sizeof(struct dm_spi_slave_platdata),
438 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
439 	.child_post_bind = spi_child_post_bind,
440 #endif
441 };
442 
443 UCLASS_DRIVER(spi_generic) = {
444 	.id		= UCLASS_SPI_GENERIC,
445 	.name		= "spi_generic",
446 };
447 
448 U_BOOT_DRIVER(spi_generic_drv) = {
449 	.name		= "spi_generic_drv",
450 	.id		= UCLASS_SPI_GENERIC,
451 };
452