xref: /linux/drivers/soundwire/stream.c (revision fee12f3c20dd5902dbd95eb41f80d3fba89336d7)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-18 Intel Corporation.
3 
4 /*
5  *  stream.c - SoundWire Bus stream operations.
6  */
7 
8 #include <linux/delay.h>
9 #include <linux/device.h>
10 #include <linux/init.h>
11 #include <linux/iopoll.h>
12 #include <linux/module.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/slab.h>
15 #include <linux/soundwire/sdw_registers.h>
16 #include <linux/soundwire/sdw.h>
17 #include <linux/soundwire/sdw_type.h>
18 #include <linux/string_choices.h>
19 #include <sound/soc.h>
20 #include "bus.h"
21 
22 #define SDW_PORT_PREP_POLL_USEC	1000
23 
24 /*
25  * Array of supported rows and columns as per MIPI SoundWire Specification 1.1
26  *
27  * The rows are arranged as per the array index value programmed
28  * in register. The index 15 has dummy value 0 in order to fill hole.
29  */
30 int sdw_rows[SDW_FRAME_ROWS] = {48, 50, 60, 64, 75, 80, 125, 147,
31 			96, 100, 120, 128, 150, 160, 250, 0,
32 			192, 200, 240, 256, 72, 144, 90, 180};
33 EXPORT_SYMBOL(sdw_rows);
34 
35 int sdw_cols[SDW_FRAME_COLS] = {2, 4, 6, 8, 10, 12, 14, 16};
36 EXPORT_SYMBOL(sdw_cols);
37 
38 int sdw_find_col_index(int col)
39 {
40 	int i;
41 
42 	for (i = 0; i < SDW_FRAME_COLS; i++) {
43 		if (sdw_cols[i] == col)
44 			return i;
45 	}
46 
47 	pr_warn("Requested column not found, selecting lowest column no: 2\n");
48 	return 0;
49 }
50 EXPORT_SYMBOL(sdw_find_col_index);
51 
52 int sdw_find_row_index(int row)
53 {
54 	int i;
55 
56 	for (i = 0; i < SDW_FRAME_ROWS; i++) {
57 		if (sdw_rows[i] == row)
58 			return i;
59 	}
60 
61 	pr_warn("Requested row not found, selecting lowest row no: 48\n");
62 	return 0;
63 }
64 EXPORT_SYMBOL(sdw_find_row_index);
65 
66 static int _sdw_program_slave_port_params(struct sdw_bus *bus,
67 					  struct sdw_slave *slave,
68 					  struct sdw_transport_params *t_params,
69 					  enum sdw_dpn_type type)
70 {
71 	u32 addr1, addr2, addr3, addr4;
72 	int ret;
73 	u16 wbuf;
74 
75 	if (bus->params.next_bank) {
76 		addr1 = SDW_DPN_OFFSETCTRL2_B1(t_params->port_num);
77 		addr2 = SDW_DPN_BLOCKCTRL3_B1(t_params->port_num);
78 		addr3 = SDW_DPN_SAMPLECTRL2_B1(t_params->port_num);
79 		addr4 = SDW_DPN_HCTRL_B1(t_params->port_num);
80 	} else {
81 		addr1 = SDW_DPN_OFFSETCTRL2_B0(t_params->port_num);
82 		addr2 = SDW_DPN_BLOCKCTRL3_B0(t_params->port_num);
83 		addr3 = SDW_DPN_SAMPLECTRL2_B0(t_params->port_num);
84 		addr4 = SDW_DPN_HCTRL_B0(t_params->port_num);
85 	}
86 
87 	/* Program DPN_OffsetCtrl2 registers */
88 	ret = sdw_write_no_pm(slave, addr1, t_params->offset2);
89 	if (ret < 0) {
90 		dev_err(bus->dev, "DPN_OffsetCtrl2 register write failed\n");
91 		return ret;
92 	}
93 
94 	/* DP0 does not implement BlockCtrl3 */
95 	if (t_params->port_num) {
96 		/* Program DPN_BlockCtrl3 register */
97 		ret = sdw_write_no_pm(slave, addr2, t_params->blk_pkg_mode);
98 		if (ret < 0) {
99 			dev_err(bus->dev, "DPN_BlockCtrl3 register write failed\n");
100 			return ret;
101 		}
102 	}
103 
104 	/*
105 	 * Data ports are FULL, SIMPLE and REDUCED. This function handles
106 	 * FULL and REDUCED only and beyond this point only FULL is
107 	 * handled, so bail out if we are not FULL data port type
108 	 */
109 	if (type != SDW_DPN_FULL)
110 		return ret;
111 
112 	/* Program DPN_SampleCtrl2 register */
113 	wbuf = FIELD_GET(SDW_DPN_SAMPLECTRL_HIGH, t_params->sample_interval - 1);
114 
115 	ret = sdw_write_no_pm(slave, addr3, wbuf);
116 	if (ret < 0) {
117 		dev_err(bus->dev, "DPN_SampleCtrl2 register write failed\n");
118 		return ret;
119 	}
120 
121 	/* Program DPN_HCtrl register */
122 	wbuf = FIELD_PREP(SDW_DPN_HCTRL_HSTART, t_params->hstart);
123 	wbuf |= FIELD_PREP(SDW_DPN_HCTRL_HSTOP, t_params->hstop);
124 
125 	ret = sdw_write_no_pm(slave, addr4, wbuf);
126 	if (ret < 0)
127 		dev_err(bus->dev, "DPN_HCtrl register write failed\n");
128 
129 	return ret;
130 }
131 
132 static int sdw_program_slave_port_params(struct sdw_bus *bus,
133 					 struct sdw_slave_runtime *s_rt,
134 					 struct sdw_port_runtime *p_rt)
135 {
136 	struct sdw_transport_params *t_params = &p_rt->transport_params;
137 	struct sdw_port_params *p_params = &p_rt->port_params;
138 	struct sdw_slave_prop *slave_prop = &s_rt->slave->prop;
139 	u32 addr1, addr2, addr3, addr4, addr5, addr6;
140 	enum sdw_dpn_type port_type;
141 	bool read_only_wordlength;
142 	int ret;
143 	u8 wbuf;
144 
145 	if (s_rt->slave->is_mockup_device)
146 		return 0;
147 
148 	if (t_params->port_num) {
149 		struct sdw_dpn_prop *dpn_prop;
150 
151 		dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave, s_rt->direction,
152 						  t_params->port_num);
153 		if (!dpn_prop)
154 			return -EINVAL;
155 
156 		read_only_wordlength = dpn_prop->read_only_wordlength;
157 		port_type = dpn_prop->type;
158 	} else {
159 		read_only_wordlength = false;
160 		port_type = SDW_DPN_FULL;
161 	}
162 
163 	addr1 = SDW_DPN_PORTCTRL(t_params->port_num);
164 	addr2 = SDW_DPN_BLOCKCTRL1(t_params->port_num);
165 
166 	if (bus->params.next_bank) {
167 		addr3 = SDW_DPN_SAMPLECTRL1_B1(t_params->port_num);
168 		addr4 = SDW_DPN_OFFSETCTRL1_B1(t_params->port_num);
169 		addr5 = SDW_DPN_BLOCKCTRL2_B1(t_params->port_num);
170 		addr6 = SDW_DPN_LANECTRL_B1(t_params->port_num);
171 
172 	} else {
173 		addr3 = SDW_DPN_SAMPLECTRL1_B0(t_params->port_num);
174 		addr4 = SDW_DPN_OFFSETCTRL1_B0(t_params->port_num);
175 		addr5 = SDW_DPN_BLOCKCTRL2_B0(t_params->port_num);
176 		addr6 = SDW_DPN_LANECTRL_B0(t_params->port_num);
177 	}
178 
179 	/* Program DPN_PortCtrl register */
180 	wbuf = FIELD_PREP(SDW_DPN_PORTCTRL_DATAMODE, p_params->data_mode);
181 	wbuf |= FIELD_PREP(SDW_DPN_PORTCTRL_FLOWMODE, p_params->flow_mode);
182 
183 	ret = sdw_update_no_pm(s_rt->slave, addr1, 0xF, wbuf);
184 	if (ret < 0) {
185 		dev_err(&s_rt->slave->dev,
186 			"DPN_PortCtrl register write failed for port %d\n",
187 			t_params->port_num);
188 		return ret;
189 	}
190 
191 	if (!read_only_wordlength) {
192 		/* Program DPN_BlockCtrl1 register */
193 		ret = sdw_write_no_pm(s_rt->slave, addr2, (p_params->bps - 1));
194 		if (ret < 0) {
195 			dev_err(&s_rt->slave->dev,
196 				"DPN_BlockCtrl1 register write failed for port %d\n",
197 				t_params->port_num);
198 			return ret;
199 		}
200 	}
201 
202 	/* Program DPN_SampleCtrl1 register */
203 	wbuf = (t_params->sample_interval - 1) & SDW_DPN_SAMPLECTRL_LOW;
204 	ret = sdw_write_no_pm(s_rt->slave, addr3, wbuf);
205 	if (ret < 0) {
206 		dev_err(&s_rt->slave->dev,
207 			"DPN_SampleCtrl1 register write failed for port %d\n",
208 			t_params->port_num);
209 		return ret;
210 	}
211 
212 	/* Program DPN_OffsetCtrl1 registers */
213 	ret = sdw_write_no_pm(s_rt->slave, addr4, t_params->offset1);
214 	if (ret < 0) {
215 		dev_err(&s_rt->slave->dev,
216 			"DPN_OffsetCtrl1 register write failed for port %d\n",
217 			t_params->port_num);
218 		return ret;
219 	}
220 
221 	/* Program DPN_BlockCtrl2 register*/
222 	if (t_params->blk_grp_ctrl_valid) {
223 		ret = sdw_write_no_pm(s_rt->slave, addr5, t_params->blk_grp_ctrl);
224 		if (ret < 0) {
225 			dev_err(&s_rt->slave->dev,
226 				"DPN_BlockCtrl2 reg write failed for port %d\n",
227 				t_params->port_num);
228 			return ret;
229 		}
230 	}
231 
232 	/* program DPN_LaneCtrl register */
233 	if (slave_prop->lane_control_support) {
234 		ret = sdw_write_no_pm(s_rt->slave, addr6, t_params->lane_ctrl);
235 		if (ret < 0) {
236 			dev_err(&s_rt->slave->dev,
237 				"DPN_LaneCtrl register write failed for port %d\n",
238 				t_params->port_num);
239 			return ret;
240 		}
241 	}
242 
243 	if (port_type != SDW_DPN_SIMPLE) {
244 		ret = _sdw_program_slave_port_params(bus, s_rt->slave,
245 						     t_params, port_type);
246 		if (ret < 0)
247 			dev_err(&s_rt->slave->dev,
248 				"Transport reg write failed for port: %d\n",
249 				t_params->port_num);
250 	}
251 
252 	return ret;
253 }
254 
255 static int sdw_program_master_port_params(struct sdw_bus *bus,
256 					  struct sdw_port_runtime *p_rt)
257 {
258 	int ret;
259 
260 	/*
261 	 * we need to set transport and port parameters for the port.
262 	 * Transport parameters refers to the sample interval, offsets and
263 	 * hstart/stop etc of the data. Port parameters refers to word
264 	 * length, flow mode etc of the port
265 	 */
266 	ret = bus->port_ops->dpn_set_port_transport_params(bus,
267 					&p_rt->transport_params,
268 					bus->params.next_bank);
269 	if (ret < 0)
270 		return ret;
271 
272 	return bus->port_ops->dpn_set_port_params(bus,
273 						  &p_rt->port_params,
274 						  bus->params.next_bank);
275 }
276 
277 /**
278  * sdw_program_port_params() - Programs transport parameters of Master(s)
279  * and Slave(s)
280  *
281  * @m_rt: Master stream runtime
282  */
283 static int sdw_program_port_params(struct sdw_master_runtime *m_rt)
284 {
285 	struct sdw_slave_runtime *s_rt;
286 	struct sdw_bus *bus = m_rt->bus;
287 	struct sdw_port_runtime *p_rt;
288 	int ret = 0;
289 
290 	/* Program transport & port parameters for Slave(s) */
291 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
292 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
293 			ret = sdw_program_slave_port_params(bus, s_rt, p_rt);
294 			if (ret < 0)
295 				return ret;
296 		}
297 	}
298 
299 	/* Program transport & port parameters for Master(s) */
300 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
301 		ret = sdw_program_master_port_params(bus, p_rt);
302 		if (ret < 0)
303 			return ret;
304 	}
305 
306 	return 0;
307 }
308 
309 /**
310  * sdw_enable_disable_slave_ports: Enable/disable slave data port
311  *
312  * @bus: bus instance
313  * @s_rt: slave runtime
314  * @p_rt: port runtime
315  * @en: enable or disable operation
316  *
317  * This function only sets the enable/disable bits in the relevant bank, the
318  * actual enable/disable is done with a bank switch
319  */
320 static int sdw_enable_disable_slave_ports(struct sdw_bus *bus,
321 					  struct sdw_slave_runtime *s_rt,
322 					  struct sdw_port_runtime *p_rt,
323 					  bool en)
324 {
325 	struct sdw_transport_params *t_params = &p_rt->transport_params;
326 	u32 addr;
327 	int ret;
328 
329 	if (bus->params.next_bank)
330 		addr = SDW_DPN_CHANNELEN_B1(p_rt->num);
331 	else
332 		addr = SDW_DPN_CHANNELEN_B0(p_rt->num);
333 
334 	/*
335 	 * Since bus doesn't support sharing a port across two streams,
336 	 * it is safe to reset this register
337 	 */
338 	if (en)
339 		ret = sdw_write_no_pm(s_rt->slave, addr, p_rt->ch_mask);
340 	else
341 		ret = sdw_write_no_pm(s_rt->slave, addr, 0x0);
342 
343 	if (ret < 0)
344 		dev_err(&s_rt->slave->dev,
345 			"Slave chn_en reg write failed:%d port:%d\n",
346 			ret, t_params->port_num);
347 
348 	return ret;
349 }
350 
351 static int sdw_enable_disable_master_ports(struct sdw_master_runtime *m_rt,
352 					   struct sdw_port_runtime *p_rt,
353 					   bool en)
354 {
355 	struct sdw_transport_params *t_params = &p_rt->transport_params;
356 	struct sdw_bus *bus = m_rt->bus;
357 	struct sdw_enable_ch enable_ch;
358 	int ret;
359 
360 	enable_ch.port_num = p_rt->num;
361 	enable_ch.ch_mask = p_rt->ch_mask;
362 	enable_ch.enable = en;
363 
364 	/* Perform Master port channel(s) enable/disable */
365 	if (bus->port_ops->dpn_port_enable_ch) {
366 		ret = bus->port_ops->dpn_port_enable_ch(bus,
367 							&enable_ch,
368 							bus->params.next_bank);
369 		if (ret < 0) {
370 			dev_err(bus->dev,
371 				"Master chn_en write failed:%d port:%d\n",
372 				ret, t_params->port_num);
373 			return ret;
374 		}
375 	} else {
376 		dev_err(bus->dev,
377 			"dpn_port_enable_ch not supported, %s failed\n",
378 			str_enable_disable(en));
379 		return -EINVAL;
380 	}
381 
382 	return 0;
383 }
384 
385 /**
386  * sdw_enable_disable_ports() - Enable/disable port(s) for Master and
387  * Slave(s)
388  *
389  * @m_rt: Master stream runtime
390  * @en: mode (enable/disable)
391  */
392 static int sdw_enable_disable_ports(struct sdw_master_runtime *m_rt, bool en)
393 {
394 	struct sdw_port_runtime *s_port, *m_port;
395 	struct sdw_slave_runtime *s_rt;
396 	int ret = 0;
397 
398 	/* Enable/Disable Slave port(s) */
399 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
400 		list_for_each_entry(s_port, &s_rt->port_list, port_node) {
401 			ret = sdw_enable_disable_slave_ports(m_rt->bus, s_rt,
402 							     s_port, en);
403 			if (ret < 0)
404 				return ret;
405 		}
406 	}
407 
408 	/* Enable/Disable Master port(s) */
409 	list_for_each_entry(m_port, &m_rt->port_list, port_node) {
410 		ret = sdw_enable_disable_master_ports(m_rt, m_port, en);
411 		if (ret < 0)
412 			return ret;
413 	}
414 
415 	return 0;
416 }
417 
418 static int sdw_do_port_prep(struct sdw_slave_runtime *s_rt,
419 			    struct sdw_prepare_ch prep_ch,
420 			    enum sdw_port_prep_ops cmd)
421 {
422 	int ret = 0;
423 	struct sdw_slave *slave = s_rt->slave;
424 
425 	mutex_lock(&slave->sdw_dev_lock);
426 
427 	if (slave->probed) {
428 		struct device *dev = &slave->dev;
429 		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
430 
431 		if (drv->ops && drv->ops->port_prep) {
432 			ret = drv->ops->port_prep(slave, &prep_ch, cmd);
433 			if (ret < 0)
434 				dev_err(dev, "Slave Port Prep cmd %d failed: %d\n",
435 					cmd, ret);
436 		}
437 	}
438 
439 	mutex_unlock(&slave->sdw_dev_lock);
440 
441 	return ret;
442 }
443 
444 static int sdw_prep_deprep_slave_ports(struct sdw_bus *bus,
445 				       struct sdw_slave_runtime *s_rt,
446 				       struct sdw_port_runtime *p_rt,
447 				       bool prep)
448 {
449 	struct sdw_dpn_prop *dpn_prop;
450 	struct sdw_prepare_ch prep_ch;
451 	u32 imp_def_interrupts;
452 	bool simple_ch_prep_sm;
453 	u32 ch_prep_timeout;
454 	bool intr = false;
455 	int ret = 0, val;
456 	u32 addr;
457 
458 	prep_ch.num = p_rt->num;
459 	prep_ch.ch_mask = p_rt->ch_mask;
460 
461 	if (p_rt->num) {
462 		dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave, s_rt->direction, prep_ch.num);
463 		if (!dpn_prop) {
464 			dev_err(bus->dev,
465 				"Slave Port:%d properties not found\n", prep_ch.num);
466 			return -EINVAL;
467 		}
468 
469 		imp_def_interrupts = dpn_prop->imp_def_interrupts;
470 		simple_ch_prep_sm = dpn_prop->simple_ch_prep_sm;
471 		ch_prep_timeout = dpn_prop->ch_prep_timeout;
472 	} else {
473 		struct sdw_dp0_prop *dp0_prop = s_rt->slave->prop.dp0_prop;
474 
475 		if (!dp0_prop) {
476 			dev_err(bus->dev,
477 				"Slave DP0 properties not found\n");
478 			return -EINVAL;
479 		}
480 		imp_def_interrupts = dp0_prop->imp_def_interrupts;
481 		simple_ch_prep_sm =  dp0_prop->simple_ch_prep_sm;
482 		ch_prep_timeout = dp0_prop->ch_prep_timeout;
483 	}
484 
485 	prep_ch.prepare = prep;
486 
487 	prep_ch.bank = bus->params.next_bank;
488 
489 	if (imp_def_interrupts || !simple_ch_prep_sm ||
490 	    bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL)
491 		intr = true;
492 
493 	/*
494 	 * Enable interrupt before Port prepare.
495 	 * For Port de-prepare, it is assumed that port
496 	 * was prepared earlier
497 	 */
498 	if (prep && intr) {
499 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
500 					     imp_def_interrupts);
501 		if (ret < 0)
502 			return ret;
503 	}
504 
505 	/* Inform slave about the impending port prepare */
506 	sdw_do_port_prep(s_rt, prep_ch, prep ? SDW_OPS_PORT_PRE_PREP : SDW_OPS_PORT_PRE_DEPREP);
507 
508 	/* Prepare Slave port implementing CP_SM */
509 	if (!simple_ch_prep_sm) {
510 		addr = SDW_DPN_PREPARECTRL(p_rt->num);
511 
512 		if (prep)
513 			ret = sdw_write_no_pm(s_rt->slave, addr, p_rt->ch_mask);
514 		else
515 			ret = sdw_write_no_pm(s_rt->slave, addr, 0x0);
516 
517 		if (ret < 0) {
518 			dev_err(&s_rt->slave->dev,
519 				"Slave prep_ctrl reg write failed\n");
520 			return ret;
521 		}
522 
523 		/*
524 		 * Poll for NOT_PREPARED==0. Cannot use the interrupt because
525 		 * this code holds bus_lock which blocks interrupt handling.
526 		 */
527 		ret = read_poll_timeout(sdw_read_no_pm, val,
528 					(val < 0) || ((val & p_rt->ch_mask) == 0),
529 					SDW_PORT_PREP_POLL_USEC, ch_prep_timeout * USEC_PER_MSEC,
530 					false, s_rt->slave, SDW_DPN_PREPARESTATUS(p_rt->num));
531 		if (ret || (val < 0)) {
532 			if (val < 0)
533 				ret = val;
534 
535 			dev_err(&s_rt->slave->dev,
536 				"Chn prep failed for port %d: %d\n", prep_ch.num, ret);
537 			return ret;
538 		}
539 	}
540 
541 	/* Inform slaves about ports prepared */
542 	sdw_do_port_prep(s_rt, prep_ch, prep ? SDW_OPS_PORT_POST_PREP : SDW_OPS_PORT_POST_DEPREP);
543 
544 	/* Disable interrupt after Port de-prepare */
545 	if (!prep && intr)
546 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
547 					     imp_def_interrupts);
548 
549 	return ret;
550 }
551 
552 static int sdw_prep_deprep_master_ports(struct sdw_master_runtime *m_rt,
553 					struct sdw_port_runtime *p_rt,
554 					bool prep)
555 {
556 	struct sdw_transport_params *t_params = &p_rt->transport_params;
557 	struct sdw_bus *bus = m_rt->bus;
558 	const struct sdw_master_port_ops *ops = bus->port_ops;
559 	struct sdw_prepare_ch prep_ch;
560 	int ret = 0;
561 
562 	prep_ch.num = p_rt->num;
563 	prep_ch.ch_mask = p_rt->ch_mask;
564 	prep_ch.prepare = prep; /* Prepare/De-prepare */
565 	prep_ch.bank = bus->params.next_bank;
566 
567 	/* Pre-prepare/Pre-deprepare port(s) */
568 	if (ops->dpn_port_prep) {
569 		ret = ops->dpn_port_prep(bus, &prep_ch);
570 		if (ret < 0) {
571 			dev_err(bus->dev, "Port prepare failed for port:%d\n",
572 				t_params->port_num);
573 			return ret;
574 		}
575 	}
576 
577 	return ret;
578 }
579 
580 /**
581  * sdw_prep_deprep_ports() - Prepare/De-prepare port(s) for Master(s) and
582  * Slave(s)
583  *
584  * @m_rt: Master runtime handle
585  * @prep: Prepare or De-prepare
586  */
587 static int sdw_prep_deprep_ports(struct sdw_master_runtime *m_rt, bool prep)
588 {
589 	struct sdw_slave_runtime *s_rt;
590 	struct sdw_port_runtime *p_rt;
591 	int ret = 0;
592 
593 	/* Prepare/De-prepare Slave port(s) */
594 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
595 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
596 			ret = sdw_prep_deprep_slave_ports(m_rt->bus, s_rt,
597 							  p_rt, prep);
598 			if (ret < 0)
599 				return ret;
600 		}
601 	}
602 
603 	/* Prepare/De-prepare Master port(s) */
604 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
605 		ret = sdw_prep_deprep_master_ports(m_rt, p_rt, prep);
606 		if (ret < 0)
607 			return ret;
608 	}
609 
610 	return ret;
611 }
612 
613 /**
614  * sdw_notify_config() - Notify bus configuration
615  *
616  * @m_rt: Master runtime handle
617  *
618  * This function notifies the Master(s) and Slave(s) of the
619  * new bus configuration.
620  */
621 static int sdw_notify_config(struct sdw_master_runtime *m_rt)
622 {
623 	struct sdw_slave_runtime *s_rt;
624 	struct sdw_bus *bus = m_rt->bus;
625 	struct sdw_slave *slave;
626 	int ret;
627 
628 	if (bus->ops->set_bus_conf) {
629 		ret = bus->ops->set_bus_conf(bus, &bus->params);
630 		if (ret < 0)
631 			return ret;
632 	}
633 
634 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
635 		slave = s_rt->slave;
636 
637 		mutex_lock(&slave->sdw_dev_lock);
638 
639 		if (slave->probed) {
640 			struct device *dev = &slave->dev;
641 			struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
642 
643 			if (drv->ops && drv->ops->bus_config) {
644 				ret = drv->ops->bus_config(slave, &bus->params);
645 				if (ret < 0) {
646 					dev_err(dev, "Notify Slave: %d failed\n",
647 						slave->dev_num);
648 					mutex_unlock(&slave->sdw_dev_lock);
649 					return ret;
650 				}
651 			}
652 		}
653 
654 		mutex_unlock(&slave->sdw_dev_lock);
655 	}
656 
657 	return 0;
658 }
659 
660 /**
661  * sdw_program_params() - Program transport and port parameters for Master(s)
662  * and Slave(s)
663  *
664  * @bus: SDW bus instance
665  * @prepare: true if sdw_program_params() is called by _prepare.
666  */
667 static int sdw_program_params(struct sdw_bus *bus, bool prepare)
668 {
669 	struct sdw_master_runtime *m_rt;
670 	struct sdw_slave *slave;
671 	int ret = 0;
672 	u32 addr1;
673 
674 	/* Check if all Peripherals comply with SDCA */
675 	list_for_each_entry(slave, &bus->slaves, node) {
676 		if (!slave->dev_num_sticky)
677 			continue;
678 		if (!is_clock_scaling_supported_by_slave(slave)) {
679 			dev_dbg(&slave->dev, "The Peripheral doesn't comply with SDCA\n");
680 			goto manager_runtime;
681 		}
682 	}
683 
684 	if (bus->params.next_bank)
685 		addr1 = SDW_SCP_BUSCLOCK_SCALE_B1;
686 	else
687 		addr1 = SDW_SCP_BUSCLOCK_SCALE_B0;
688 
689 	/* Program SDW_SCP_BUSCLOCK_SCALE if all Peripherals comply with SDCA */
690 	list_for_each_entry(slave, &bus->slaves, node) {
691 		int scale_index;
692 		u8 base;
693 
694 		if (!slave->dev_num_sticky)
695 			continue;
696 		scale_index = sdw_slave_get_scale_index(slave, &base);
697 		if (scale_index < 0)
698 			return scale_index;
699 
700 		ret = sdw_write_no_pm(slave, addr1, scale_index);
701 		if (ret < 0) {
702 			dev_err(&slave->dev, "SDW_SCP_BUSCLOCK_SCALE register write failed\n");
703 			return ret;
704 		}
705 	}
706 
707 manager_runtime:
708 	list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) {
709 
710 		/*
711 		 * this loop walks through all master runtimes for a
712 		 * bus, but the ports can only be configured while
713 		 * explicitly preparing a stream or handling an
714 		 * already-prepared stream otherwise.
715 		 */
716 		if (!prepare &&
717 		    m_rt->stream->state == SDW_STREAM_CONFIGURED)
718 			continue;
719 
720 		ret = sdw_program_port_params(m_rt);
721 		if (ret < 0) {
722 			dev_err(bus->dev,
723 				"Program transport params failed: %d\n", ret);
724 			return ret;
725 		}
726 
727 		ret = sdw_notify_config(m_rt);
728 		if (ret < 0) {
729 			dev_err(bus->dev,
730 				"Notify bus config failed: %d\n", ret);
731 			return ret;
732 		}
733 
734 		/* Enable port(s) on alternate bank for all active streams */
735 		if (m_rt->stream->state != SDW_STREAM_ENABLED)
736 			continue;
737 
738 		ret = sdw_enable_disable_ports(m_rt, true);
739 		if (ret < 0) {
740 			dev_err(bus->dev, "Enable channel failed: %d\n", ret);
741 			return ret;
742 		}
743 	}
744 
745 	return ret;
746 }
747 
748 static int sdw_bank_switch(struct sdw_bus *bus, int m_rt_count)
749 {
750 	int col_index, row_index;
751 	bool multi_link;
752 	struct sdw_msg *wr_msg;
753 	u8 *wbuf;
754 	int ret;
755 	u16 addr;
756 
757 	wr_msg = kzalloc_obj(*wr_msg);
758 	if (!wr_msg)
759 		return -ENOMEM;
760 
761 	wbuf = kzalloc_obj(*wbuf);
762 	if (!wbuf) {
763 		ret = -ENOMEM;
764 		goto error_1;
765 	}
766 
767 	/* Get row and column index to program register */
768 	col_index = sdw_find_col_index(bus->params.col);
769 	row_index = sdw_find_row_index(bus->params.row);
770 	wbuf[0] = col_index | (row_index << 3);
771 
772 	if (bus->params.next_bank)
773 		addr = SDW_SCP_FRAMECTRL_B1;
774 	else
775 		addr = SDW_SCP_FRAMECTRL_B0;
776 
777 	sdw_fill_msg(wr_msg, NULL, addr, 1, SDW_BROADCAST_DEV_NUM,
778 		     SDW_MSG_FLAG_WRITE, wbuf);
779 	wr_msg->ssp_sync = true;
780 
781 	/*
782 	 * Set the multi_link flag only when both the hardware supports
783 	 * and hardware-based sync is required
784 	 */
785 	multi_link = bus->multi_link && (m_rt_count >= bus->hw_sync_min_links);
786 
787 	if (multi_link)
788 		ret = sdw_transfer_defer(bus, wr_msg);
789 	else
790 		ret = sdw_transfer(bus, wr_msg);
791 
792 	if (ret < 0 && ret != -ENODATA) {
793 		dev_err(bus->dev, "Slave frame_ctrl reg write failed\n");
794 		goto error;
795 	}
796 
797 	if (!multi_link) {
798 		kfree(wbuf);
799 		kfree(wr_msg);
800 		bus->defer_msg.msg = NULL;
801 		bus->params.curr_bank = !bus->params.curr_bank;
802 		bus->params.next_bank = !bus->params.next_bank;
803 	}
804 
805 	return 0;
806 
807 error:
808 	kfree(wbuf);
809 error_1:
810 	kfree(wr_msg);
811 	bus->defer_msg.msg = NULL;
812 	return ret;
813 }
814 
815 /**
816  * sdw_ml_sync_bank_switch: Multilink register bank switch
817  *
818  * @bus: SDW bus instance
819  * @multi_link: whether this is a multi-link stream with hardware-based sync
820  *
821  * Caller function should free the buffers on error
822  */
823 static int sdw_ml_sync_bank_switch(struct sdw_bus *bus, bool multi_link)
824 {
825 	unsigned long time_left;
826 
827 	if (!multi_link)
828 		return 0;
829 
830 	/* Wait for completion of transfer */
831 	time_left = wait_for_completion_timeout(&bus->defer_msg.complete,
832 						bus->bank_switch_timeout);
833 
834 	if (!time_left) {
835 		dev_err(bus->dev, "Controller Timed out on bank switch\n");
836 		return -ETIMEDOUT;
837 	}
838 
839 	bus->params.curr_bank = !bus->params.curr_bank;
840 	bus->params.next_bank = !bus->params.next_bank;
841 
842 	if (bus->defer_msg.msg) {
843 		kfree(bus->defer_msg.msg->buf);
844 		kfree(bus->defer_msg.msg);
845 		bus->defer_msg.msg = NULL;
846 	}
847 
848 	return 0;
849 }
850 
851 static int do_bank_switch(struct sdw_stream_runtime *stream)
852 {
853 	struct sdw_master_runtime *m_rt;
854 	const struct sdw_master_ops *ops;
855 	struct sdw_bus *bus;
856 	bool multi_link = false;
857 	int m_rt_count;
858 	int ret = 0;
859 
860 	m_rt_count = stream->m_rt_count;
861 
862 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
863 		bus = m_rt->bus;
864 		ops = bus->ops;
865 
866 		if (bus->multi_link && m_rt_count >= bus->hw_sync_min_links) {
867 			multi_link = true;
868 			mutex_lock(&bus->msg_lock);
869 		}
870 
871 		/* Pre-bank switch */
872 		if (ops->pre_bank_switch) {
873 			ret = ops->pre_bank_switch(bus);
874 			if (ret < 0) {
875 				dev_err(bus->dev,
876 					"Pre bank switch op failed: %d\n", ret);
877 				goto msg_unlock;
878 			}
879 		}
880 
881 		/*
882 		 * Perform Bank switch operation.
883 		 * For multi link cases, the actual bank switch is
884 		 * synchronized across all Masters and happens later as a
885 		 * part of post_bank_switch ops.
886 		 */
887 		ret = sdw_bank_switch(bus, m_rt_count);
888 		if (ret < 0) {
889 			dev_err(bus->dev, "Bank switch failed: %d\n", ret);
890 			goto error;
891 		}
892 	}
893 
894 	/*
895 	 * For multi link cases, it is expected that the bank switch is
896 	 * triggered by the post_bank_switch for the first Master in the list
897 	 * and for the other Masters the post_bank_switch() should return doing
898 	 * nothing.
899 	 */
900 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
901 		bus = m_rt->bus;
902 		ops = bus->ops;
903 
904 		/* Post-bank switch */
905 		if (ops->post_bank_switch) {
906 			ret = ops->post_bank_switch(bus);
907 			if (ret < 0) {
908 				dev_err(bus->dev,
909 					"Post bank switch op failed: %d\n",
910 					ret);
911 				goto error;
912 			}
913 		} else if (multi_link) {
914 			dev_err(bus->dev,
915 				"Post bank switch ops not implemented\n");
916 			ret = -EINVAL;
917 			goto error;
918 		}
919 
920 		/* Set the bank switch timeout to default, if not set */
921 		if (!bus->bank_switch_timeout)
922 			bus->bank_switch_timeout = DEFAULT_BANK_SWITCH_TIMEOUT;
923 
924 		/* Check if bank switch was successful */
925 		ret = sdw_ml_sync_bank_switch(bus, multi_link);
926 		if (ret < 0) {
927 			dev_err(bus->dev,
928 				"multi link bank switch failed: %d\n", ret);
929 			goto error;
930 		}
931 
932 		if (multi_link)
933 			mutex_unlock(&bus->msg_lock);
934 	}
935 
936 	return ret;
937 
938 error:
939 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
940 		bus = m_rt->bus;
941 		if (bus->defer_msg.msg) {
942 			kfree(bus->defer_msg.msg->buf);
943 			kfree(bus->defer_msg.msg);
944 			bus->defer_msg.msg = NULL;
945 		}
946 	}
947 
948 msg_unlock:
949 
950 	if (multi_link) {
951 		list_for_each_entry(m_rt, &stream->master_list, stream_node) {
952 			bus = m_rt->bus;
953 			if (mutex_is_locked(&bus->msg_lock))
954 				mutex_unlock(&bus->msg_lock);
955 		}
956 	}
957 
958 	return ret;
959 }
960 
961 static struct sdw_port_runtime *sdw_port_alloc(struct list_head *port_list)
962 {
963 	struct sdw_port_runtime *p_rt;
964 
965 	p_rt = kzalloc_obj(*p_rt);
966 	if (!p_rt)
967 		return NULL;
968 
969 	list_add_tail(&p_rt->port_node, port_list);
970 
971 	return p_rt;
972 }
973 
974 static int sdw_port_config(struct sdw_port_runtime *p_rt,
975 			   const struct sdw_port_config *port_config,
976 			   int port_index)
977 {
978 	p_rt->ch_mask = port_config[port_index].ch_mask;
979 	p_rt->num = port_config[port_index].num;
980 
981 	/*
982 	 * TODO: Check port capabilities for requested configuration
983 	 */
984 
985 	return 0;
986 }
987 
988 static void sdw_port_free(struct sdw_port_runtime *p_rt)
989 {
990 	list_del(&p_rt->port_node);
991 	kfree(p_rt);
992 }
993 
994 static bool sdw_slave_port_allocated(struct sdw_slave_runtime *s_rt)
995 {
996 	return !list_empty(&s_rt->port_list);
997 }
998 
999 static void sdw_slave_port_free(struct sdw_slave *slave,
1000 				struct sdw_stream_runtime *stream)
1001 {
1002 	struct sdw_port_runtime *p_rt, *_p_rt;
1003 	struct sdw_master_runtime *m_rt;
1004 	struct sdw_slave_runtime *s_rt;
1005 
1006 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1007 		list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
1008 			if (s_rt->slave != slave)
1009 				continue;
1010 
1011 			list_for_each_entry_safe(p_rt, _p_rt,
1012 						 &s_rt->port_list, port_node) {
1013 				sdw_port_free(p_rt);
1014 			}
1015 		}
1016 	}
1017 }
1018 
1019 static int sdw_slave_port_alloc(struct sdw_slave *slave,
1020 				struct sdw_slave_runtime *s_rt,
1021 				unsigned int num_config)
1022 {
1023 	struct sdw_port_runtime *p_rt;
1024 	int i;
1025 
1026 	/* Iterate for number of ports to perform initialization */
1027 	for (i = 0; i < num_config; i++) {
1028 		p_rt = sdw_port_alloc(&s_rt->port_list);
1029 		if (!p_rt)
1030 			return -ENOMEM;
1031 	}
1032 
1033 	return 0;
1034 }
1035 
1036 static int sdw_slave_port_is_valid_range(struct device *dev, int num)
1037 {
1038 	if (!SDW_VALID_PORT_RANGE(num)) {
1039 		dev_err(dev, "SoundWire: Invalid port number :%d\n", num);
1040 		return -EINVAL;
1041 	}
1042 
1043 	return 0;
1044 }
1045 
1046 static int sdw_slave_port_config(struct sdw_slave *slave,
1047 				 struct sdw_slave_runtime *s_rt,
1048 				 const struct sdw_port_config *port_config,
1049 				 bool is_bpt_stream)
1050 {
1051 	struct sdw_port_runtime *p_rt;
1052 	int ret;
1053 	int i;
1054 
1055 	i = 0;
1056 	list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
1057 		/*
1058 		 * TODO: Check valid port range as defined by DisCo/
1059 		 * slave
1060 		 */
1061 		if (!is_bpt_stream) {
1062 			ret = sdw_slave_port_is_valid_range(&slave->dev, port_config[i].num);
1063 			if (ret < 0)
1064 				return ret;
1065 		} else if (port_config[i].num) {
1066 			return -EINVAL;
1067 		}
1068 
1069 		ret = sdw_port_config(p_rt, port_config, i);
1070 		if (ret < 0)
1071 			return ret;
1072 		i++;
1073 	}
1074 
1075 	return 0;
1076 }
1077 
1078 static bool sdw_master_port_allocated(struct sdw_master_runtime *m_rt)
1079 {
1080 	return !list_empty(&m_rt->port_list);
1081 }
1082 
1083 static void sdw_master_port_free(struct sdw_master_runtime *m_rt)
1084 {
1085 	struct sdw_port_runtime *p_rt, *_p_rt;
1086 
1087 	list_for_each_entry_safe(p_rt, _p_rt, &m_rt->port_list, port_node) {
1088 		sdw_port_free(p_rt);
1089 	}
1090 }
1091 
1092 static int sdw_master_port_alloc(struct sdw_master_runtime *m_rt,
1093 				 unsigned int num_ports)
1094 {
1095 	struct sdw_port_runtime *p_rt;
1096 	int i;
1097 
1098 	/* Iterate for number of ports to perform initialization */
1099 	for (i = 0; i < num_ports; i++) {
1100 		p_rt = sdw_port_alloc(&m_rt->port_list);
1101 		if (!p_rt)
1102 			return -ENOMEM;
1103 	}
1104 
1105 	return 0;
1106 }
1107 
1108 static int sdw_master_port_config(struct sdw_master_runtime *m_rt,
1109 				  const struct sdw_port_config *port_config)
1110 {
1111 	struct sdw_port_runtime *p_rt;
1112 	int ret;
1113 	int i;
1114 
1115 	i = 0;
1116 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
1117 		ret = sdw_port_config(p_rt, port_config, i);
1118 		if (ret < 0)
1119 			return ret;
1120 		i++;
1121 	}
1122 
1123 	return 0;
1124 }
1125 
1126 /**
1127  * sdw_slave_rt_alloc() - Allocate a Slave runtime handle.
1128  *
1129  * @slave: Slave handle
1130  * @m_rt: Master runtime handle
1131  *
1132  * This function is to be called with bus_lock held.
1133  */
1134 static struct sdw_slave_runtime
1135 *sdw_slave_rt_alloc(struct sdw_slave *slave,
1136 		    struct sdw_master_runtime *m_rt)
1137 {
1138 	struct sdw_slave_runtime *s_rt;
1139 
1140 	s_rt = kzalloc_obj(*s_rt);
1141 	if (!s_rt)
1142 		return NULL;
1143 
1144 	INIT_LIST_HEAD(&s_rt->port_list);
1145 	s_rt->slave = slave;
1146 
1147 	list_add_tail(&s_rt->m_rt_node, &m_rt->slave_rt_list);
1148 
1149 	return s_rt;
1150 }
1151 
1152 /**
1153  * sdw_slave_rt_config() - Configure a Slave runtime handle.
1154  *
1155  * @s_rt: Slave runtime handle
1156  * @stream_config: Stream configuration
1157  *
1158  * This function is to be called with bus_lock held.
1159  */
1160 static int sdw_slave_rt_config(struct sdw_slave_runtime *s_rt,
1161 			       struct sdw_stream_config *stream_config)
1162 {
1163 	s_rt->ch_count = stream_config->ch_count;
1164 	s_rt->direction = stream_config->direction;
1165 
1166 	return 0;
1167 }
1168 
1169 static struct sdw_slave_runtime *sdw_slave_rt_find(struct sdw_slave *slave,
1170 						   struct sdw_stream_runtime *stream)
1171 {
1172 	struct sdw_slave_runtime *s_rt, *_s_rt;
1173 	struct sdw_master_runtime *m_rt;
1174 
1175 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1176 		/* Retrieve Slave runtime handle */
1177 		list_for_each_entry_safe(s_rt, _s_rt,
1178 					 &m_rt->slave_rt_list, m_rt_node) {
1179 			if (s_rt->slave == slave)
1180 				return s_rt;
1181 		}
1182 	}
1183 	return NULL;
1184 }
1185 
1186 /**
1187  * sdw_slave_rt_free() - Free Slave(s) runtime handle
1188  *
1189  * @slave: Slave handle.
1190  * @stream: Stream runtime handle.
1191  *
1192  * This function is to be called with bus_lock held.
1193  */
1194 static void sdw_slave_rt_free(struct sdw_slave *slave,
1195 			      struct sdw_stream_runtime *stream)
1196 {
1197 	struct sdw_slave_runtime *s_rt;
1198 
1199 	s_rt = sdw_slave_rt_find(slave, stream);
1200 	if (s_rt) {
1201 		list_del(&s_rt->m_rt_node);
1202 		kfree(s_rt);
1203 	}
1204 }
1205 
1206 static struct sdw_master_runtime
1207 *sdw_master_rt_find(struct sdw_bus *bus,
1208 		    struct sdw_stream_runtime *stream)
1209 {
1210 	struct sdw_master_runtime *m_rt;
1211 
1212 	/* Retrieve Bus handle if already available */
1213 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1214 		if (m_rt->bus == bus)
1215 			return m_rt;
1216 	}
1217 
1218 	return NULL;
1219 }
1220 
1221 /**
1222  * sdw_master_rt_alloc() - Allocates a Master runtime handle
1223  *
1224  * @bus: SDW bus instance
1225  * @stream: Stream runtime handle.
1226  *
1227  * This function is to be called with bus_lock held.
1228  */
1229 static struct sdw_master_runtime
1230 *sdw_master_rt_alloc(struct sdw_bus *bus,
1231 		     struct sdw_stream_runtime *stream)
1232 {
1233 	struct sdw_master_runtime *m_rt, *walk_m_rt;
1234 	struct list_head *insert_after;
1235 
1236 	if (stream->type == SDW_STREAM_BPT) {
1237 		if (bus->stream_refcount > 0 || bus->bpt_stream_refcount > 0) {
1238 			dev_err(bus->dev, "%s: %d/%d audio/BPT stream already allocated\n",
1239 				__func__, bus->stream_refcount, bus->bpt_stream_refcount);
1240 			return ERR_PTR(-EBUSY);
1241 		}
1242 	} else {
1243 		if (bus->bpt_stream_refcount > 0) {
1244 			dev_err(bus->dev, "%s: BPT stream already allocated\n",
1245 				__func__);
1246 			return ERR_PTR(-EAGAIN);
1247 		}
1248 	}
1249 
1250 	m_rt = kzalloc_obj(*m_rt);
1251 	if (!m_rt)
1252 		return NULL;
1253 
1254 	/* Initialization of Master runtime handle */
1255 	INIT_LIST_HEAD(&m_rt->port_list);
1256 	INIT_LIST_HEAD(&m_rt->slave_rt_list);
1257 
1258 	/*
1259 	 * Add in order of bus id so that when taking the bus_lock
1260 	 * of multiple buses they will always be taken in the same
1261 	 * order to prevent a mutex deadlock.
1262 	 */
1263 	insert_after = &stream->master_list;
1264 	list_for_each_entry_reverse(walk_m_rt, &stream->master_list, stream_node) {
1265 		if (walk_m_rt->bus->id < bus->id) {
1266 			insert_after = &walk_m_rt->stream_node;
1267 			break;
1268 		}
1269 	}
1270 	list_add(&m_rt->stream_node, insert_after);
1271 
1272 	list_add_tail(&m_rt->bus_node, &bus->m_rt_list);
1273 
1274 	m_rt->bus = bus;
1275 	m_rt->stream = stream;
1276 
1277 	bus->stream_refcount++;
1278 	if (stream->type == SDW_STREAM_BPT)
1279 		bus->bpt_stream_refcount++;
1280 
1281 	return m_rt;
1282 }
1283 
1284 /**
1285  * sdw_master_rt_config() - Configure Master runtime handle
1286  *
1287  * @m_rt: Master runtime handle
1288  * @stream_config: Stream configuration
1289  *
1290  * This function is to be called with bus_lock held.
1291  */
1292 
1293 static int sdw_master_rt_config(struct sdw_master_runtime *m_rt,
1294 				struct sdw_stream_config *stream_config)
1295 {
1296 	m_rt->ch_count = stream_config->ch_count;
1297 	m_rt->direction = stream_config->direction;
1298 
1299 	return 0;
1300 }
1301 
1302 /**
1303  * sdw_master_rt_free() - Free Master runtime handle
1304  *
1305  * @m_rt: Master runtime node
1306  * @stream: Stream runtime handle.
1307  *
1308  * This function is to be called with bus_lock held
1309  * It frees the Master runtime handle and associated Slave(s) runtime
1310  * handle. If this is called first then sdw_slave_rt_free() will have
1311  * no effect as Slave(s) runtime handle would already be freed up.
1312  */
1313 static void sdw_master_rt_free(struct sdw_master_runtime *m_rt,
1314 			       struct sdw_stream_runtime *stream)
1315 {
1316 	struct sdw_slave_runtime *s_rt, *_s_rt;
1317 	struct sdw_bus *bus = m_rt->bus;
1318 
1319 	list_for_each_entry_safe(s_rt, _s_rt, &m_rt->slave_rt_list, m_rt_node) {
1320 		sdw_slave_port_free(s_rt->slave, stream);
1321 		sdw_slave_rt_free(s_rt->slave, stream);
1322 	}
1323 
1324 	list_del(&m_rt->stream_node);
1325 	list_del(&m_rt->bus_node);
1326 	kfree(m_rt);
1327 
1328 	if (stream->type == SDW_STREAM_BPT)
1329 		bus->bpt_stream_refcount--;
1330 	bus->stream_refcount--;
1331 }
1332 
1333 /**
1334  * sdw_config_stream() - Configure the allocated stream
1335  *
1336  * @dev: SDW device
1337  * @stream: SoundWire stream
1338  * @stream_config: Stream configuration for audio stream
1339  * @is_slave: is API called from Slave or Master
1340  *
1341  * This function is to be called with bus_lock held.
1342  */
1343 static int sdw_config_stream(struct device *dev,
1344 			     struct sdw_stream_runtime *stream,
1345 			     struct sdw_stream_config *stream_config,
1346 			     bool is_slave)
1347 {
1348 	/*
1349 	 * Update the stream rate, channel and bps based on data
1350 	 * source. For more than one data source (multilink),
1351 	 * match the rate, bps, stream type and increment number of channels.
1352 	 *
1353 	 * If rate/bps is zero, it means the values are not set, so skip
1354 	 * comparison and allow the value to be set and stored in stream
1355 	 */
1356 	if (stream->params.rate &&
1357 	    stream->params.rate != stream_config->frame_rate) {
1358 		dev_err(dev, "rate not matching, stream:%s\n", stream->name);
1359 		return -EINVAL;
1360 	}
1361 
1362 	if (stream->params.bps &&
1363 	    stream->params.bps != stream_config->bps) {
1364 		dev_err(dev, "bps not matching, stream:%s\n", stream->name);
1365 		return -EINVAL;
1366 	}
1367 
1368 	stream->type = stream_config->type;
1369 	stream->params.rate = stream_config->frame_rate;
1370 	stream->params.bps = stream_config->bps;
1371 
1372 	/* TODO: Update this check during Device-device support */
1373 	if (is_slave)
1374 		stream->params.ch_count += stream_config->ch_count;
1375 
1376 	return 0;
1377 }
1378 
1379 /**
1380  * sdw_get_slave_dpn_prop() - Get Slave port capabilities
1381  *
1382  * @slave: Slave handle
1383  * @direction: Data direction.
1384  * @port_num: Port number
1385  */
1386 struct sdw_dpn_prop *sdw_get_slave_dpn_prop(struct sdw_slave *slave,
1387 					    enum sdw_data_direction direction,
1388 					    unsigned int port_num)
1389 {
1390 	struct sdw_dpn_prop *dpn_prop;
1391 	u8 num_ports;
1392 	int i;
1393 
1394 	if (!port_num) {
1395 		dev_err(&slave->dev, "%s: port_num is zero\n", __func__);
1396 		return NULL;
1397 	}
1398 
1399 	if (direction == SDW_DATA_DIR_TX) {
1400 		num_ports = hweight32(slave->prop.source_ports);
1401 		dpn_prop = slave->prop.src_dpn_prop;
1402 	} else {
1403 		num_ports = hweight32(slave->prop.sink_ports);
1404 		dpn_prop = slave->prop.sink_dpn_prop;
1405 	}
1406 
1407 	for (i = 0; i < num_ports; i++) {
1408 		if (dpn_prop[i].num == port_num)
1409 			return &dpn_prop[i];
1410 	}
1411 
1412 	return NULL;
1413 }
1414 
1415 /**
1416  * sdw_acquire_bus_lock: Acquire bus lock for all Master runtime(s)
1417  *
1418  * @stream: SoundWire stream
1419  *
1420  * Acquire bus_lock for each of the master runtime(m_rt) part of this
1421  * stream to reconfigure the bus.
1422  * NOTE: This function is called from SoundWire stream ops and is
1423  * expected that a global lock is held before acquiring bus_lock.
1424  */
1425 static void sdw_acquire_bus_lock(struct sdw_stream_runtime *stream)
1426 {
1427 	struct sdw_master_runtime *m_rt;
1428 	struct sdw_bus *bus;
1429 
1430 	/* Iterate for all Master(s) in Master list */
1431 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1432 		bus = m_rt->bus;
1433 
1434 		mutex_lock(&bus->bus_lock);
1435 	}
1436 }
1437 
1438 /**
1439  * sdw_release_bus_lock: Release bus lock for all Master runtime(s)
1440  *
1441  * @stream: SoundWire stream
1442  *
1443  * Release the previously held bus_lock after reconfiguring the bus.
1444  * NOTE: This function is called from SoundWire stream ops and is
1445  * expected that a global lock is held before releasing bus_lock.
1446  */
1447 static void sdw_release_bus_lock(struct sdw_stream_runtime *stream)
1448 {
1449 	struct sdw_master_runtime *m_rt;
1450 	struct sdw_bus *bus;
1451 
1452 	/* Iterate for all Master(s) in Master list */
1453 	list_for_each_entry_reverse(m_rt, &stream->master_list, stream_node) {
1454 		bus = m_rt->bus;
1455 		mutex_unlock(&bus->bus_lock);
1456 	}
1457 }
1458 
1459 static int _sdw_prepare_stream(struct sdw_stream_runtime *stream,
1460 			       bool update_params)
1461 {
1462 	struct sdw_master_runtime *m_rt;
1463 	struct sdw_bus *bus;
1464 	struct sdw_master_prop *prop;
1465 	struct sdw_bus_params params;
1466 	int ret;
1467 
1468 	/* Prepare  Master(s) and Slave(s) port(s) associated with stream */
1469 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1470 		bus = m_rt->bus;
1471 		prop = &bus->prop;
1472 		memcpy(&params, &bus->params, sizeof(params));
1473 
1474 		/* TODO: Support Asynchronous mode */
1475 		if ((prop->max_clk_freq % stream->params.rate) != 0) {
1476 			dev_err(bus->dev, "Async mode not supported\n");
1477 			return -EINVAL;
1478 		}
1479 
1480 		if (update_params) {
1481 			/* Increment cumulative bus bandwidth */
1482 			/* TODO: Update this during Device-Device support */
1483 			bus->params.bandwidth += m_rt->stream->params.rate *
1484 				m_rt->ch_count * m_rt->stream->params.bps;
1485 
1486 			/* Compute params */
1487 			if (bus->compute_params) {
1488 				ret = bus->compute_params(bus, stream);
1489 				if (ret < 0) {
1490 					dev_err(bus->dev, "Compute params failed: %d\n",
1491 						ret);
1492 					goto restore_params;
1493 				}
1494 			}
1495 		}
1496 
1497 		/* Program params */
1498 		ret = sdw_program_params(bus, true);
1499 		if (ret < 0) {
1500 			dev_err(bus->dev, "Program params failed: %d\n", ret);
1501 			goto restore_params;
1502 		}
1503 	}
1504 
1505 	ret = do_bank_switch(stream);
1506 	if (ret < 0) {
1507 		pr_err("%s: do_bank_switch failed: %d\n", __func__, ret);
1508 		goto restore_params;
1509 	}
1510 
1511 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1512 		bus = m_rt->bus;
1513 
1514 		/* Prepare port(s) on the new clock configuration */
1515 		ret = sdw_prep_deprep_ports(m_rt, true);
1516 		if (ret < 0) {
1517 			dev_err(bus->dev, "Prepare port(s) failed ret = %d\n",
1518 				ret);
1519 			goto restore_params;
1520 		}
1521 	}
1522 
1523 	stream->state = SDW_STREAM_PREPARED;
1524 
1525 	return ret;
1526 
1527 restore_params:
1528 	memcpy(&bus->params, &params, sizeof(params));
1529 	return ret;
1530 }
1531 
1532 /**
1533  * sdw_prepare_stream() - Prepare SoundWire stream
1534  *
1535  * @stream: Soundwire stream
1536  *
1537  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1538  */
1539 int sdw_prepare_stream(struct sdw_stream_runtime *stream)
1540 {
1541 	bool update_params = true;
1542 	int ret;
1543 
1544 	if (!stream) {
1545 		pr_err("SoundWire: Handle not found for stream\n");
1546 		return -EINVAL;
1547 	}
1548 
1549 	sdw_acquire_bus_lock(stream);
1550 
1551 	if (stream->state == SDW_STREAM_PREPARED) {
1552 		ret = 0;
1553 		goto state_err;
1554 	}
1555 
1556 	if (stream->state != SDW_STREAM_CONFIGURED &&
1557 	    stream->state != SDW_STREAM_DEPREPARED &&
1558 	    stream->state != SDW_STREAM_DISABLED) {
1559 		pr_err("%s: %s: inconsistent state state %d\n",
1560 		       __func__, stream->name, stream->state);
1561 		ret = -EINVAL;
1562 		goto state_err;
1563 	}
1564 
1565 	/*
1566 	 * when the stream is DISABLED, this means sdw_prepare_stream()
1567 	 * is called as a result of an underflow or a resume operation.
1568 	 * In this case, the bus parameters shall not be recomputed, but
1569 	 * still need to be re-applied
1570 	 */
1571 	if (stream->state == SDW_STREAM_DISABLED)
1572 		update_params = false;
1573 
1574 	ret = _sdw_prepare_stream(stream, update_params);
1575 
1576 state_err:
1577 	sdw_release_bus_lock(stream);
1578 	return ret;
1579 }
1580 EXPORT_SYMBOL(sdw_prepare_stream);
1581 
1582 static int _sdw_enable_stream(struct sdw_stream_runtime *stream)
1583 {
1584 	struct sdw_master_runtime *m_rt;
1585 	struct sdw_bus *bus;
1586 	int ret;
1587 
1588 	/* Enable Master(s) and Slave(s) port(s) associated with stream */
1589 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1590 		bus = m_rt->bus;
1591 
1592 		/* Program params */
1593 		ret = sdw_program_params(bus, false);
1594 		if (ret < 0) {
1595 			dev_err(bus->dev, "%s: Program params failed: %d\n", __func__, ret);
1596 			return ret;
1597 		}
1598 
1599 		/* Enable port(s) */
1600 		ret = sdw_enable_disable_ports(m_rt, true);
1601 		if (ret < 0) {
1602 			dev_err(bus->dev,
1603 				"Enable port(s) failed ret: %d\n", ret);
1604 			return ret;
1605 		}
1606 	}
1607 
1608 	ret = do_bank_switch(stream);
1609 	if (ret < 0) {
1610 		pr_err("%s: do_bank_switch failed: %d\n", __func__, ret);
1611 		return ret;
1612 	}
1613 
1614 	stream->state = SDW_STREAM_ENABLED;
1615 	return 0;
1616 }
1617 
1618 /**
1619  * sdw_enable_stream() - Enable SoundWire stream
1620  *
1621  * @stream: Soundwire stream
1622  *
1623  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1624  */
1625 int sdw_enable_stream(struct sdw_stream_runtime *stream)
1626 {
1627 	int ret;
1628 
1629 	if (!stream) {
1630 		pr_err("SoundWire: Handle not found for stream\n");
1631 		return -EINVAL;
1632 	}
1633 
1634 	sdw_acquire_bus_lock(stream);
1635 
1636 	if (stream->state == SDW_STREAM_ENABLED) {
1637 		ret = 0;
1638 		goto state_err;
1639 	}
1640 
1641 	if (stream->state != SDW_STREAM_PREPARED &&
1642 	    stream->state != SDW_STREAM_DISABLED) {
1643 		pr_err("%s: %s: inconsistent state state %d\n",
1644 		       __func__, stream->name, stream->state);
1645 		ret = -EINVAL;
1646 		goto state_err;
1647 	}
1648 
1649 	ret = _sdw_enable_stream(stream);
1650 
1651 state_err:
1652 	sdw_release_bus_lock(stream);
1653 	return ret;
1654 }
1655 EXPORT_SYMBOL(sdw_enable_stream);
1656 
1657 static int _sdw_disable_stream(struct sdw_stream_runtime *stream)
1658 {
1659 	struct sdw_master_runtime *m_rt;
1660 	int ret;
1661 
1662 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1663 		struct sdw_bus *bus = m_rt->bus;
1664 
1665 		/* Disable port(s) */
1666 		ret = sdw_enable_disable_ports(m_rt, false);
1667 		if (ret < 0) {
1668 			dev_err(bus->dev, "Disable port(s) failed: %d\n", ret);
1669 			return ret;
1670 		}
1671 	}
1672 	stream->state = SDW_STREAM_DISABLED;
1673 
1674 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1675 		struct sdw_bus *bus = m_rt->bus;
1676 
1677 		/* Program params */
1678 		ret = sdw_program_params(bus, false);
1679 		if (ret < 0) {
1680 			dev_err(bus->dev, "%s: Program params failed: %d\n", __func__, ret);
1681 			return ret;
1682 		}
1683 	}
1684 
1685 	ret = do_bank_switch(stream);
1686 	if (ret < 0) {
1687 		pr_err("%s: do_bank_switch failed: %d\n", __func__, ret);
1688 		return ret;
1689 	}
1690 
1691 	/* make sure alternate bank (previous current) is also disabled */
1692 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1693 		struct sdw_bus *bus = m_rt->bus;
1694 
1695 		/* Disable port(s) */
1696 		ret = sdw_enable_disable_ports(m_rt, false);
1697 		if (ret < 0) {
1698 			dev_err(bus->dev, "Disable port(s) failed: %d\n", ret);
1699 			return ret;
1700 		}
1701 	}
1702 
1703 	return 0;
1704 }
1705 
1706 /**
1707  * sdw_disable_stream() - Disable SoundWire stream
1708  *
1709  * @stream: Soundwire stream
1710  *
1711  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1712  */
1713 int sdw_disable_stream(struct sdw_stream_runtime *stream)
1714 {
1715 	int ret;
1716 
1717 	if (!stream) {
1718 		pr_err("SoundWire: Handle not found for stream\n");
1719 		return -EINVAL;
1720 	}
1721 
1722 	sdw_acquire_bus_lock(stream);
1723 
1724 	if (stream->state == SDW_STREAM_DISABLED) {
1725 		ret = 0;
1726 		goto state_err;
1727 	}
1728 
1729 	if (stream->state != SDW_STREAM_ENABLED) {
1730 		pr_err("%s: %s: inconsistent state state %d\n",
1731 		       __func__, stream->name, stream->state);
1732 		ret = -EINVAL;
1733 		goto state_err;
1734 	}
1735 
1736 	ret = _sdw_disable_stream(stream);
1737 
1738 state_err:
1739 	sdw_release_bus_lock(stream);
1740 	return ret;
1741 }
1742 EXPORT_SYMBOL(sdw_disable_stream);
1743 
1744 static int _sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1745 {
1746 	struct sdw_master_runtime *m_rt;
1747 	struct sdw_port_runtime *p_rt;
1748 	unsigned int multi_lane_bandwidth;
1749 	unsigned int bandwidth;
1750 	struct sdw_bus *bus;
1751 	int state = stream->state;
1752 	int ret = 0;
1753 
1754 	/*
1755 	 * first mark the state as DEPREPARED so that it is not taken into account
1756 	 * for bit allocation
1757 	 */
1758 	stream->state = SDW_STREAM_DEPREPARED;
1759 
1760 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1761 		bus = m_rt->bus;
1762 		/* De-prepare port(s) */
1763 		ret = sdw_prep_deprep_ports(m_rt, false);
1764 		if (ret < 0) {
1765 			dev_err(bus->dev,
1766 				"De-prepare port(s) failed: %d\n", ret);
1767 			stream->state = state;
1768 			return ret;
1769 		}
1770 
1771 		multi_lane_bandwidth = 0;
1772 
1773 		list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
1774 			if (!p_rt->lane)
1775 				continue;
1776 
1777 			bandwidth = m_rt->stream->params.rate * hweight32(p_rt->ch_mask) *
1778 				    m_rt->stream->params.bps;
1779 			multi_lane_bandwidth += bandwidth;
1780 			bus->lane_used_bandwidth[p_rt->lane] -= bandwidth;
1781 			if (!bus->lane_used_bandwidth[p_rt->lane])
1782 				p_rt->lane = 0;
1783 		}
1784 		/* TODO: Update this during Device-Device support */
1785 		bandwidth = m_rt->stream->params.rate * m_rt->ch_count * m_rt->stream->params.bps;
1786 		bus->params.bandwidth -= bandwidth - multi_lane_bandwidth;
1787 
1788 		/* Compute params */
1789 		if (bus->compute_params) {
1790 			ret = bus->compute_params(bus, stream);
1791 			if (ret < 0) {
1792 				dev_err(bus->dev, "Compute params failed: %d\n",
1793 					ret);
1794 				stream->state = state;
1795 				return ret;
1796 			}
1797 		}
1798 
1799 		/* Program params */
1800 		ret = sdw_program_params(bus, false);
1801 		if (ret < 0) {
1802 			dev_err(bus->dev, "%s: Program params failed: %d\n", __func__, ret);
1803 			stream->state = state;
1804 			return ret;
1805 		}
1806 	}
1807 
1808 	return do_bank_switch(stream);
1809 }
1810 
1811 /**
1812  * sdw_deprepare_stream() - Deprepare SoundWire stream
1813  *
1814  * @stream: Soundwire stream
1815  *
1816  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1817  */
1818 int sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1819 {
1820 	int ret;
1821 
1822 	if (!stream) {
1823 		pr_err("SoundWire: Handle not found for stream\n");
1824 		return -EINVAL;
1825 	}
1826 
1827 	sdw_acquire_bus_lock(stream);
1828 
1829 	if (stream->state == SDW_STREAM_DEPREPARED) {
1830 		ret = 0;
1831 		goto state_err;
1832 	}
1833 
1834 	if (stream->state != SDW_STREAM_PREPARED &&
1835 	    stream->state != SDW_STREAM_DISABLED) {
1836 		pr_err("%s: %s: inconsistent state state %d\n",
1837 		       __func__, stream->name, stream->state);
1838 		ret = -EINVAL;
1839 		goto state_err;
1840 	}
1841 
1842 	ret = _sdw_deprepare_stream(stream);
1843 
1844 state_err:
1845 	sdw_release_bus_lock(stream);
1846 	return ret;
1847 }
1848 EXPORT_SYMBOL(sdw_deprepare_stream);
1849 
1850 static int set_stream(struct snd_pcm_substream *substream,
1851 		      struct sdw_stream_runtime *sdw_stream)
1852 {
1853 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
1854 	struct snd_soc_dai *dai;
1855 	int ret = 0;
1856 	int i;
1857 
1858 	/* Set stream pointer on all DAIs */
1859 	for_each_rtd_dais(rtd, i, dai) {
1860 		ret = snd_soc_dai_set_stream(dai, sdw_stream, substream->stream);
1861 		if (ret < 0) {
1862 			dev_err(rtd->dev, "failed to set stream pointer on dai %s\n", dai->name);
1863 			break;
1864 		}
1865 	}
1866 
1867 	return ret;
1868 }
1869 
1870 /**
1871  * sdw_alloc_stream() - Allocate and return stream runtime
1872  *
1873  * @stream_name: SoundWire stream name
1874  * @type: stream type (could be PCM ,PDM or BPT)
1875  *
1876  * Allocates a SoundWire stream runtime instance.
1877  * sdw_alloc_stream should be called only once per stream. Typically
1878  * invoked from ALSA/ASoC machine/platform driver.
1879  */
1880 struct sdw_stream_runtime *sdw_alloc_stream(const char *stream_name, enum sdw_stream_type type)
1881 {
1882 	struct sdw_stream_runtime *stream;
1883 
1884 	stream = kzalloc_obj(*stream);
1885 	if (!stream)
1886 		return NULL;
1887 
1888 	stream->name = stream_name;
1889 	INIT_LIST_HEAD(&stream->master_list);
1890 	stream->state = SDW_STREAM_ALLOCATED;
1891 	stream->m_rt_count = 0;
1892 	stream->type = type;
1893 
1894 	return stream;
1895 }
1896 EXPORT_SYMBOL(sdw_alloc_stream);
1897 
1898 /**
1899  * sdw_startup_stream() - Startup SoundWire stream
1900  *
1901  * @sdw_substream: Soundwire stream
1902  *
1903  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1904  */
1905 int sdw_startup_stream(void *sdw_substream)
1906 {
1907 	struct snd_pcm_substream *substream = sdw_substream;
1908 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
1909 	struct sdw_stream_runtime *sdw_stream;
1910 	char *name;
1911 	int ret;
1912 
1913 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1914 		name = kasprintf(GFP_KERNEL, "%s-Playback", substream->name);
1915 	else
1916 		name = kasprintf(GFP_KERNEL, "%s-Capture", substream->name);
1917 
1918 	if (!name)
1919 		return -ENOMEM;
1920 
1921 	sdw_stream = sdw_alloc_stream(name, SDW_STREAM_PCM);
1922 	if (!sdw_stream) {
1923 		dev_err(rtd->dev, "alloc stream failed for substream DAI %s\n", substream->name);
1924 		ret = -ENOMEM;
1925 		goto error;
1926 	}
1927 
1928 	ret = set_stream(substream, sdw_stream);
1929 	if (ret < 0)
1930 		goto release_stream;
1931 	return 0;
1932 
1933 release_stream:
1934 	sdw_release_stream(sdw_stream);
1935 	set_stream(substream, NULL);
1936 error:
1937 	kfree(name);
1938 	return ret;
1939 }
1940 EXPORT_SYMBOL(sdw_startup_stream);
1941 
1942 /**
1943  * sdw_shutdown_stream() - Shutdown SoundWire stream
1944  *
1945  * @sdw_substream: Soundwire stream
1946  *
1947  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1948  */
1949 void sdw_shutdown_stream(void *sdw_substream)
1950 {
1951 	struct snd_pcm_substream *substream = sdw_substream;
1952 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
1953 	struct sdw_stream_runtime *sdw_stream;
1954 	struct snd_soc_dai *dai;
1955 
1956 	/* Find stream from first CPU DAI */
1957 	dai = snd_soc_rtd_to_cpu(rtd, 0);
1958 
1959 	sdw_stream = snd_soc_dai_get_stream(dai, substream->stream);
1960 
1961 	if (IS_ERR(sdw_stream)) {
1962 		dev_err(rtd->dev, "no stream found for DAI %s\n", dai->name);
1963 		return;
1964 	}
1965 
1966 	/* release memory */
1967 	kfree(sdw_stream->name);
1968 	sdw_release_stream(sdw_stream);
1969 
1970 	/* clear DAI data */
1971 	set_stream(substream, NULL);
1972 }
1973 EXPORT_SYMBOL(sdw_shutdown_stream);
1974 
1975 /**
1976  * sdw_release_stream() - Free the assigned stream runtime
1977  *
1978  * @stream: SoundWire stream runtime
1979  *
1980  * sdw_release_stream should be called only once per stream
1981  */
1982 void sdw_release_stream(struct sdw_stream_runtime *stream)
1983 {
1984 	kfree(stream);
1985 }
1986 EXPORT_SYMBOL(sdw_release_stream);
1987 
1988 /**
1989  * sdw_stream_add_master() - Allocate and add master runtime to a stream
1990  *
1991  * @bus: SDW Bus instance
1992  * @stream_config: Stream configuration for audio stream
1993  * @port_config: Port configuration for audio stream
1994  * @num_ports: Number of ports
1995  * @stream: SoundWire stream
1996  */
1997 int sdw_stream_add_master(struct sdw_bus *bus,
1998 			  struct sdw_stream_config *stream_config,
1999 			  const struct sdw_port_config *port_config,
2000 			  unsigned int num_ports,
2001 			  struct sdw_stream_runtime *stream)
2002 {
2003 	struct sdw_master_runtime *m_rt;
2004 	bool alloc_master_rt = false;
2005 	int ret;
2006 
2007 	mutex_lock(&bus->bus_lock);
2008 
2009 	/*
2010 	 * For multi link streams, add the second master only if
2011 	 * the bus supports it.
2012 	 * Check if bus->multi_link is set
2013 	 */
2014 	if (!bus->multi_link && stream->m_rt_count > 0) {
2015 		dev_err(bus->dev,
2016 			"Multilink not supported, link %d\n", bus->link_id);
2017 		ret = -EINVAL;
2018 		goto unlock;
2019 	}
2020 
2021 	/*
2022 	 * check if Master is already allocated (e.g. as a result of Slave adding
2023 	 * it first), if so skip allocation and go to configuration
2024 	 */
2025 	m_rt = sdw_master_rt_find(bus, stream);
2026 	if (!m_rt) {
2027 		m_rt = sdw_master_rt_alloc(bus, stream);
2028 		if (IS_ERR(m_rt)) {
2029 			ret = PTR_ERR(m_rt);
2030 			dev_err(bus->dev, "%s: Master runtime alloc failed for stream:%s: %d\n",
2031 				__func__, stream->name, ret);
2032 			goto unlock;
2033 		}
2034 		if (!m_rt) {
2035 			dev_err(bus->dev, "%s: Master runtime alloc failed for stream:%s\n",
2036 				__func__, stream->name);
2037 			ret = -ENOMEM;
2038 			goto unlock;
2039 		}
2040 
2041 		alloc_master_rt = true;
2042 	}
2043 
2044 	if (!sdw_master_port_allocated(m_rt)) {
2045 		ret = sdw_master_port_alloc(m_rt, num_ports);
2046 		if (ret)
2047 			goto alloc_error;
2048 
2049 		stream->m_rt_count++;
2050 	}
2051 
2052 	ret = sdw_master_rt_config(m_rt, stream_config);
2053 	if (ret < 0)
2054 		goto unlock;
2055 
2056 	ret = sdw_config_stream(bus->dev, stream, stream_config, false);
2057 	if (ret)
2058 		goto unlock;
2059 
2060 	ret = sdw_master_port_config(m_rt, port_config);
2061 
2062 	goto unlock;
2063 
2064 alloc_error:
2065 	/*
2066 	 * we only cleanup what was allocated in this routine
2067 	 */
2068 	if (alloc_master_rt)
2069 		sdw_master_rt_free(m_rt, stream);
2070 unlock:
2071 	mutex_unlock(&bus->bus_lock);
2072 	return ret;
2073 }
2074 EXPORT_SYMBOL(sdw_stream_add_master);
2075 
2076 /**
2077  * sdw_stream_remove_master() - Remove master from sdw_stream
2078  *
2079  * @bus: SDW Bus instance
2080  * @stream: SoundWire stream
2081  *
2082  * This removes and frees port_rt and master_rt from a stream
2083  */
2084 int sdw_stream_remove_master(struct sdw_bus *bus,
2085 			     struct sdw_stream_runtime *stream)
2086 {
2087 	struct sdw_master_runtime *m_rt, *_m_rt;
2088 
2089 	mutex_lock(&bus->bus_lock);
2090 
2091 	list_for_each_entry_safe(m_rt, _m_rt,
2092 				 &stream->master_list, stream_node) {
2093 		if (m_rt->bus != bus)
2094 			continue;
2095 
2096 		sdw_master_port_free(m_rt);
2097 		sdw_master_rt_free(m_rt, stream);
2098 		stream->m_rt_count--;
2099 	}
2100 
2101 	if (list_empty(&stream->master_list))
2102 		stream->state = SDW_STREAM_RELEASED;
2103 
2104 	mutex_unlock(&bus->bus_lock);
2105 
2106 	return 0;
2107 }
2108 EXPORT_SYMBOL(sdw_stream_remove_master);
2109 
2110 /**
2111  * sdw_stream_add_slave() - Allocate and add master/slave runtime to a stream
2112  *
2113  * @slave: SDW Slave instance
2114  * @stream_config: Stream configuration for audio stream
2115  * @stream: SoundWire stream
2116  * @port_config: Port configuration for audio stream
2117  * @num_ports: Number of ports
2118  *
2119  * It is expected that Slave is added before adding Master
2120  * to the Stream.
2121  *
2122  */
2123 int sdw_stream_add_slave(struct sdw_slave *slave,
2124 			 struct sdw_stream_config *stream_config,
2125 			 const struct sdw_port_config *port_config,
2126 			 unsigned int num_ports,
2127 			 struct sdw_stream_runtime *stream)
2128 {
2129 	struct sdw_slave_runtime *s_rt;
2130 	struct sdw_master_runtime *m_rt;
2131 	bool alloc_master_rt = false;
2132 	bool alloc_slave_rt = false;
2133 
2134 	int ret;
2135 
2136 	mutex_lock(&slave->bus->bus_lock);
2137 
2138 	/*
2139 	 * check if Master is already allocated, if so skip allocation
2140 	 * and go to configuration
2141 	 */
2142 	m_rt = sdw_master_rt_find(slave->bus, stream);
2143 	if (!m_rt) {
2144 		/*
2145 		 * If this API is invoked by Slave first then m_rt is not valid.
2146 		 * So, allocate m_rt and add Slave to it.
2147 		 */
2148 		m_rt = sdw_master_rt_alloc(slave->bus, stream);
2149 		if (IS_ERR(m_rt)) {
2150 			ret = PTR_ERR(m_rt);
2151 			dev_err(&slave->dev, "%s: Master runtime alloc failed for stream:%s: %d\n",
2152 				__func__, stream->name, ret);
2153 			goto unlock;
2154 		}
2155 		if (!m_rt) {
2156 			dev_err(&slave->dev, "%s: Master runtime alloc failed for stream:%s\n",
2157 				__func__, stream->name);
2158 			ret = -ENOMEM;
2159 			goto unlock;
2160 		}
2161 
2162 		alloc_master_rt = true;
2163 	}
2164 
2165 	s_rt = sdw_slave_rt_find(slave, stream);
2166 	if (!s_rt) {
2167 		s_rt = sdw_slave_rt_alloc(slave, m_rt);
2168 		if (!s_rt) {
2169 			dev_err(&slave->dev, "Slave runtime alloc failed for stream:%s\n",
2170 				stream->name);
2171 			ret = -ENOMEM;
2172 			goto alloc_error;
2173 		}
2174 
2175 		alloc_slave_rt = true;
2176 	}
2177 
2178 	if (!sdw_slave_port_allocated(s_rt)) {
2179 		ret = sdw_slave_port_alloc(slave, s_rt, num_ports);
2180 		if (ret)
2181 			goto alloc_error;
2182 	}
2183 
2184 	ret =  sdw_master_rt_config(m_rt, stream_config);
2185 	if (ret)
2186 		goto unlock;
2187 
2188 	ret = sdw_slave_rt_config(s_rt, stream_config);
2189 	if (ret)
2190 		goto unlock;
2191 
2192 	ret = sdw_config_stream(&slave->dev, stream, stream_config, true);
2193 	if (ret)
2194 		goto unlock;
2195 
2196 	ret = sdw_slave_port_config(slave, s_rt, port_config,
2197 				    stream->type == SDW_STREAM_BPT);
2198 	if (ret)
2199 		goto unlock;
2200 
2201 	/*
2202 	 * Change stream state to CONFIGURED on first Slave add.
2203 	 * Bus is not aware of number of Slave(s) in a stream at this
2204 	 * point so cannot depend on all Slave(s) to be added in order to
2205 	 * change stream state to CONFIGURED.
2206 	 */
2207 	stream->state = SDW_STREAM_CONFIGURED;
2208 	goto unlock;
2209 
2210 alloc_error:
2211 	/*
2212 	 * we only cleanup what was allocated in this routine. The 'else if'
2213 	 * is intentional, the 'master_rt_free' will call sdw_slave_rt_free()
2214 	 * internally.
2215 	 */
2216 	if (alloc_master_rt)
2217 		sdw_master_rt_free(m_rt, stream);
2218 	else if (alloc_slave_rt)
2219 		sdw_slave_rt_free(slave, stream);
2220 unlock:
2221 	mutex_unlock(&slave->bus->bus_lock);
2222 	return ret;
2223 }
2224 EXPORT_SYMBOL(sdw_stream_add_slave);
2225 
2226 /**
2227  * sdw_stream_remove_slave() - Remove slave from sdw_stream
2228  *
2229  * @slave: SDW Slave instance
2230  * @stream: SoundWire stream
2231  *
2232  * This removes and frees port_rt and slave_rt from a stream
2233  */
2234 int sdw_stream_remove_slave(struct sdw_slave *slave,
2235 			    struct sdw_stream_runtime *stream)
2236 {
2237 	mutex_lock(&slave->bus->bus_lock);
2238 
2239 	sdw_slave_port_free(slave, stream);
2240 	sdw_slave_rt_free(slave, stream);
2241 
2242 	mutex_unlock(&slave->bus->bus_lock);
2243 
2244 	return 0;
2245 }
2246 EXPORT_SYMBOL(sdw_stream_remove_slave);
2247