xref: /linux/drivers/spi/spi-cs42l43.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // CS42L43 SPI Controller Driver
4 //
5 // Copyright (C) 2022-2023 Cirrus Logic, Inc. and
6 //                         Cirrus Logic International Semiconductor Ltd.
7 
8 #include <linux/acpi.h>
9 #include <linux/array_size.h>
10 #include <linux/bits.h>
11 #include <linux/bitfield.h>
12 #include <linux/cleanup.h>
13 #include <linux/device.h>
14 #include <linux/errno.h>
15 #include <linux/gpio/machine.h>
16 #include <linux/gpio/property.h>
17 #include <linux/mfd/cs42l43.h>
18 #include <linux/mfd/cs42l43-regs.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/property.h>
25 #include <linux/regmap.h>
26 #include <linux/spi/spi.h>
27 #include <linux/units.h>
28 
29 #define CS42L43_FIFO_SIZE		16
30 #define CS42L43_SPI_ROOT_HZ		49152000
31 #define CS42L43_SPI_MAX_LENGTH		65532
32 
33 enum cs42l43_spi_cmd {
34 	CS42L43_WRITE,
35 	CS42L43_READ
36 };
37 
38 struct cs42l43_spi {
39 	struct device *dev;
40 	struct regmap *regmap;
41 	struct spi_controller *ctlr;
42 };
43 
44 static const unsigned int cs42l43_clock_divs[] = {
45 	2, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30
46 };
47 
48 static struct spi_board_info amp_info_template = {
49 	.modalias		= "cs35l56",
50 	.max_speed_hz		= 11 * HZ_PER_MHZ,
51 	.mode			= SPI_MODE_0,
52 };
53 
54 static const struct software_node cs42l43_gpiochip_swnode = {
55 	.name			= "cs42l43-pinctrl",
56 };
57 
58 static const struct software_node_ref_args cs42l43_cs_refs[] = {
59 	SOFTWARE_NODE_REFERENCE(&cs42l43_gpiochip_swnode, 0, GPIO_ACTIVE_LOW),
60 	SOFTWARE_NODE_REFERENCE(&swnode_gpio_undefined),
61 };
62 
63 static const struct property_entry cs42l43_cs_props[] = {
64 	PROPERTY_ENTRY_REF_ARRAY("cs-gpios", cs42l43_cs_refs),
65 	{}
66 };
67 
cs42l43_spi_tx(struct regmap * regmap,const u8 * buf,unsigned int len)68 static int cs42l43_spi_tx(struct regmap *regmap, const u8 *buf, unsigned int len)
69 {
70 	const u8 *end = buf + len;
71 	u32 val = 0;
72 	int ret;
73 
74 	while (buf < end) {
75 		const u8 *block = min(buf + CS42L43_FIFO_SIZE, end);
76 
77 		while (buf < block) {
78 			const u8 *word = min(buf + sizeof(u32), block);
79 			int pad = (buf + sizeof(u32)) - word;
80 
81 			while (buf < word) {
82 				val >>= BITS_PER_BYTE;
83 				val |= FIELD_PREP(GENMASK(31, 24), *buf);
84 
85 				buf++;
86 			}
87 
88 			val >>= pad * BITS_PER_BYTE;
89 
90 			regmap_write(regmap, CS42L43_TX_DATA, val);
91 		}
92 
93 		regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_TX_DONE_MASK);
94 
95 		ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
96 					       val, (val & CS42L43_SPI_TX_REQUEST_MASK),
97 					       1000, 5000);
98 		if (ret)
99 			return ret;
100 	}
101 
102 	return 0;
103 }
104 
cs42l43_spi_rx(struct regmap * regmap,u8 * buf,unsigned int len)105 static int cs42l43_spi_rx(struct regmap *regmap, u8 *buf, unsigned int len)
106 {
107 	u8 *end = buf + len;
108 	u32 val;
109 	int ret;
110 
111 	while (buf < end) {
112 		u8 *block = min(buf + CS42L43_FIFO_SIZE, end);
113 
114 		ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
115 					       val, (val & CS42L43_SPI_RX_REQUEST_MASK),
116 					       1000, 5000);
117 		if (ret)
118 			return ret;
119 
120 		while (buf < block) {
121 			u8 *word = min(buf + sizeof(u32), block);
122 
123 			ret = regmap_read(regmap, CS42L43_RX_DATA, &val);
124 			if (ret)
125 				return ret;
126 
127 			while (buf < word) {
128 				*buf = FIELD_GET(GENMASK(7, 0), val);
129 
130 				val >>= BITS_PER_BYTE;
131 				buf++;
132 			}
133 		}
134 
135 		regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_RX_DONE_MASK);
136 	}
137 
138 	return 0;
139 }
140 
cs42l43_transfer_one(struct spi_controller * ctlr,struct spi_device * spi,struct spi_transfer * tfr)141 static int cs42l43_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
142 				struct spi_transfer *tfr)
143 {
144 	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
145 	int i, ret = -EINVAL;
146 
147 	for (i = 0; i < ARRAY_SIZE(cs42l43_clock_divs); i++) {
148 		if (CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[i] <= tfr->speed_hz)
149 			break;
150 	}
151 
152 	if (i == ARRAY_SIZE(cs42l43_clock_divs))
153 		return -EINVAL;
154 
155 	regmap_write(priv->regmap, CS42L43_SPI_CLK_CONFIG1, i);
156 
157 	if (tfr->tx_buf) {
158 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_WRITE);
159 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG4, tfr->len - 1);
160 	} else if (tfr->rx_buf) {
161 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_READ);
162 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG5, tfr->len - 1);
163 	}
164 
165 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG1, CS42L43_SPI_START_MASK);
166 
167 	if (tfr->tx_buf)
168 		ret = cs42l43_spi_tx(priv->regmap, (const u8 *)tfr->tx_buf, tfr->len);
169 	else if (tfr->rx_buf)
170 		ret = cs42l43_spi_rx(priv->regmap, (u8 *)tfr->rx_buf, tfr->len);
171 
172 	return ret;
173 }
174 
cs42l43_set_cs(struct spi_device * spi,bool is_high)175 static void cs42l43_set_cs(struct spi_device *spi, bool is_high)
176 {
177 	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
178 
179 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG2, !is_high);
180 }
181 
cs42l43_prepare_message(struct spi_controller * ctlr,struct spi_message * msg)182 static int cs42l43_prepare_message(struct spi_controller *ctlr, struct spi_message *msg)
183 {
184 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
185 	struct spi_device *spi = msg->spi;
186 	unsigned int spi_config1 = 0;
187 
188 	/* select another internal CS, which doesn't exist, so CS 0 is not used */
189 	if (spi_get_csgpiod(spi, 0))
190 		spi_config1 |= 1 << CS42L43_SPI_SS_SEL_SHIFT;
191 	if (spi->mode & SPI_CPOL)
192 		spi_config1 |= CS42L43_SPI_CPOL_MASK;
193 	if (spi->mode & SPI_CPHA)
194 		spi_config1 |= CS42L43_SPI_CPHA_MASK;
195 	if (spi->mode & SPI_3WIRE)
196 		spi_config1 |= CS42L43_SPI_THREE_WIRE_MASK;
197 
198 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG1, spi_config1);
199 
200 	return 0;
201 }
202 
cs42l43_prepare_transfer_hardware(struct spi_controller * ctlr)203 static int cs42l43_prepare_transfer_hardware(struct spi_controller *ctlr)
204 {
205 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
206 	int ret;
207 
208 	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, CS42L43_SPI_MSTR_EN_MASK);
209 	if (ret)
210 		dev_err(priv->dev, "Failed to enable SPI controller: %d\n", ret);
211 
212 	return ret;
213 }
214 
cs42l43_unprepare_transfer_hardware(struct spi_controller * ctlr)215 static int cs42l43_unprepare_transfer_hardware(struct spi_controller *ctlr)
216 {
217 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
218 	int ret;
219 
220 	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, 0);
221 	if (ret)
222 		dev_err(priv->dev, "Failed to disable SPI controller: %d\n", ret);
223 
224 	return ret;
225 }
226 
cs42l43_spi_max_length(struct spi_device * spi)227 static size_t cs42l43_spi_max_length(struct spi_device *spi)
228 {
229 	return CS42L43_SPI_MAX_LENGTH;
230 }
231 
cs42l43_find_xu_node(struct fwnode_handle * fwnode)232 static struct fwnode_handle *cs42l43_find_xu_node(struct fwnode_handle *fwnode)
233 {
234 	static const u32 func_smart_amp = 0x1;
235 	struct fwnode_handle *child_fwnode, *ext_fwnode;
236 	u32 function;
237 	int ret;
238 
239 	fwnode_for_each_child_node(fwnode, child_fwnode) {
240 		acpi_handle handle = ACPI_HANDLE_FWNODE(child_fwnode);
241 
242 		ret = acpi_get_local_address(handle, &function);
243 		if (ret || function != func_smart_amp)
244 			continue;
245 
246 		ext_fwnode = fwnode_get_named_child_node(child_fwnode,
247 				"mipi-sdca-function-expansion-subproperties");
248 		if (!ext_fwnode)
249 			continue;
250 
251 		fwnode_handle_put(child_fwnode);
252 
253 		return ext_fwnode;
254 	}
255 
256 	return NULL;
257 }
258 
cs42l43_create_bridge_amp(struct cs42l43_spi * priv,const char * const name,int cs,int spkid)259 static struct spi_board_info *cs42l43_create_bridge_amp(struct cs42l43_spi *priv,
260 							const char * const name,
261 							int cs, int spkid)
262 {
263 	struct property_entry *props = NULL;
264 	struct software_node *swnode;
265 	struct spi_board_info *info;
266 
267 	if (spkid >= 0) {
268 		props = devm_kmalloc(priv->dev, sizeof(*props), GFP_KERNEL);
269 		if (!props)
270 			return NULL;
271 
272 		*props = PROPERTY_ENTRY_U32("cirrus,speaker-id", spkid);
273 	}
274 
275 	swnode = devm_kmalloc(priv->dev, sizeof(*swnode), GFP_KERNEL);
276 	if (!swnode)
277 		return NULL;
278 
279 	*swnode = SOFTWARE_NODE(name, props, NULL);
280 
281 	info = devm_kmemdup(priv->dev, &amp_info_template,
282 			    sizeof(amp_info_template), GFP_KERNEL);
283 	if (!info)
284 		return NULL;
285 
286 	info->chip_select = cs;
287 	info->swnode = swnode;
288 
289 	return info;
290 }
291 
cs42l43_release_of_node(void * data)292 static void cs42l43_release_of_node(void *data)
293 {
294 	fwnode_handle_put(data);
295 }
296 
cs42l43_release_sw_node(void * data)297 static void cs42l43_release_sw_node(void *data)
298 {
299 	software_node_unregister(&cs42l43_gpiochip_swnode);
300 }
301 
cs42l43_spi_probe(struct platform_device * pdev)302 static int cs42l43_spi_probe(struct platform_device *pdev)
303 {
304 	struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
305 	struct cs42l43_spi *priv;
306 	struct fwnode_handle *fwnode = dev_fwnode(cs42l43->dev);
307 	struct fwnode_handle *xu_fwnode __free(fwnode_handle) = cs42l43_find_xu_node(fwnode);
308 	int nsidecars = 0;
309 	int ret;
310 
311 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
312 	if (!priv)
313 		return -ENOMEM;
314 
315 	priv->ctlr = devm_spi_alloc_host(&pdev->dev, sizeof(*priv->ctlr));
316 	if (!priv->ctlr)
317 		return -ENOMEM;
318 
319 	spi_controller_set_devdata(priv->ctlr, priv);
320 
321 	priv->dev = &pdev->dev;
322 	priv->regmap = cs42l43->regmap;
323 
324 	priv->ctlr->prepare_message = cs42l43_prepare_message;
325 	priv->ctlr->prepare_transfer_hardware = cs42l43_prepare_transfer_hardware;
326 	priv->ctlr->unprepare_transfer_hardware = cs42l43_unprepare_transfer_hardware;
327 	priv->ctlr->transfer_one = cs42l43_transfer_one;
328 	priv->ctlr->set_cs = cs42l43_set_cs;
329 	priv->ctlr->max_transfer_size = cs42l43_spi_max_length;
330 	priv->ctlr->mode_bits = SPI_3WIRE | SPI_MODE_X_MASK;
331 	priv->ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
332 	priv->ctlr->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
333 					 SPI_BPW_MASK(32);
334 	priv->ctlr->min_speed_hz = CS42L43_SPI_ROOT_HZ /
335 				   cs42l43_clock_divs[ARRAY_SIZE(cs42l43_clock_divs) - 1];
336 	priv->ctlr->max_speed_hz = CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[0];
337 	priv->ctlr->use_gpio_descriptors = true;
338 	priv->ctlr->auto_runtime_pm = true;
339 
340 	ret = devm_pm_runtime_enable(priv->dev);
341 	if (ret)
342 		return ret;
343 
344 	pm_runtime_idle(priv->dev);
345 
346 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG6, CS42L43_FIFO_SIZE - 1);
347 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG7, CS42L43_FIFO_SIZE - 1);
348 
349 	// Disable Watchdog timer and enable stall
350 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG3, 0);
351 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG4, CS42L43_SPI_STALL_ENA_MASK);
352 
353 	if (is_of_node(fwnode)) {
354 		fwnode = fwnode_get_named_child_node(fwnode, "spi");
355 		ret = devm_add_action_or_reset(priv->dev, cs42l43_release_of_node, fwnode);
356 		if (ret)
357 			return ret;
358 	}
359 
360 	fwnode_property_read_u32(xu_fwnode, "01fa-sidecar-instances", &nsidecars);
361 
362 	if (nsidecars) {
363 		ret = software_node_register(&cs42l43_gpiochip_swnode);
364 		if (ret)
365 			return dev_err_probe(priv->dev, ret,
366 					     "Failed to register gpio swnode\n");
367 
368 		ret = devm_add_action_or_reset(priv->dev, cs42l43_release_sw_node, NULL);
369 		if (ret)
370 			return ret;
371 
372 		ret = device_create_managed_software_node(&priv->ctlr->dev,
373 							  cs42l43_cs_props, NULL);
374 		if (ret)
375 			return dev_err_probe(priv->dev, ret, "Failed to add swnode\n");
376 	} else {
377 		device_set_node(&priv->ctlr->dev, fwnode);
378 	}
379 
380 	ret = devm_spi_register_controller(priv->dev, priv->ctlr);
381 	if (ret)
382 		return dev_err_probe(priv->dev, ret,
383 				     "Failed to register SPI controller\n");
384 
385 	if (nsidecars) {
386 		struct spi_board_info *ampl_info;
387 		struct spi_board_info *ampr_info;
388 		int spkid = -EINVAL;
389 
390 		fwnode_property_read_u32(xu_fwnode, "01fa-spk-id-val", &spkid);
391 
392 		dev_dbg(priv->dev, "Found speaker ID %d\n", spkid);
393 
394 		ampl_info = cs42l43_create_bridge_amp(priv, "cs35l56-left", 0, spkid);
395 		if (!ampl_info)
396 			return -ENOMEM;
397 
398 		ampr_info = cs42l43_create_bridge_amp(priv, "cs35l56-right", 1, spkid);
399 		if (!ampr_info)
400 			return -ENOMEM;
401 
402 		if (!spi_new_device(priv->ctlr, ampl_info))
403 			return dev_err_probe(priv->dev, -ENODEV,
404 					     "Failed to create left amp slave\n");
405 
406 		if (!spi_new_device(priv->ctlr, ampr_info))
407 			return dev_err_probe(priv->dev, -ENODEV,
408 					     "Failed to create right amp slave\n");
409 	}
410 
411 	return 0;
412 }
413 
414 static const struct platform_device_id cs42l43_spi_id_table[] = {
415 	{ "cs42l43-spi", },
416 	{}
417 };
418 MODULE_DEVICE_TABLE(platform, cs42l43_spi_id_table);
419 
420 static struct platform_driver cs42l43_spi_driver = {
421 	.driver = {
422 		.name	= "cs42l43-spi",
423 	},
424 	.probe		= cs42l43_spi_probe,
425 	.id_table	= cs42l43_spi_id_table,
426 };
427 module_platform_driver(cs42l43_spi_driver);
428 
429 MODULE_IMPORT_NS(GPIO_SWNODE);
430 MODULE_DESCRIPTION("CS42L43 SPI Driver");
431 MODULE_AUTHOR("Lucas Tanure <tanureal@opensource.cirrus.com>");
432 MODULE_AUTHOR("Maciej Strozek <mstrozek@opensource.cirrus.com>");
433 MODULE_LICENSE("GPL");
434