xref: /openbmc/linux/drivers/soundwire/stream.c (revision 8365a898)
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/module.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/slab.h>
14 #include <linux/soundwire/sdw_registers.h>
15 #include <linux/soundwire/sdw.h>
16 #include "bus.h"
17 
18 /*
19  * Array of supported rows and columns as per MIPI SoundWire Specification 1.1
20  *
21  * The rows are arranged as per the array index value programmed
22  * in register. The index 15 has dummy value 0 in order to fill hole.
23  */
24 int sdw_rows[SDW_FRAME_ROWS] = {48, 50, 60, 64, 75, 80, 125, 147,
25 			96, 100, 120, 128, 150, 160, 250, 0,
26 			192, 200, 240, 256, 72, 144, 90, 180};
27 
28 int sdw_cols[SDW_FRAME_COLS] = {2, 4, 6, 8, 10, 12, 14, 16};
29 
30 int sdw_find_col_index(int col)
31 {
32 	int i;
33 
34 	for (i = 0; i < SDW_FRAME_COLS; i++) {
35 		if (sdw_cols[i] == col)
36 			return i;
37 	}
38 
39 	pr_warn("Requested column not found, selecting lowest column no: 2\n");
40 	return 0;
41 }
42 EXPORT_SYMBOL(sdw_find_col_index);
43 
44 int sdw_find_row_index(int row)
45 {
46 	int i;
47 
48 	for (i = 0; i < SDW_FRAME_ROWS; i++) {
49 		if (sdw_rows[i] == row)
50 			return i;
51 	}
52 
53 	pr_warn("Requested row not found, selecting lowest row no: 48\n");
54 	return 0;
55 }
56 EXPORT_SYMBOL(sdw_find_row_index);
57 
58 static int _sdw_program_slave_port_params(struct sdw_bus *bus,
59 					  struct sdw_slave *slave,
60 					  struct sdw_transport_params *t_params,
61 					  enum sdw_dpn_type type)
62 {
63 	u32 addr1, addr2, addr3, addr4;
64 	int ret;
65 	u16 wbuf;
66 
67 	if (bus->params.next_bank) {
68 		addr1 = SDW_DPN_OFFSETCTRL2_B1(t_params->port_num);
69 		addr2 = SDW_DPN_BLOCKCTRL3_B1(t_params->port_num);
70 		addr3 = SDW_DPN_SAMPLECTRL2_B1(t_params->port_num);
71 		addr4 = SDW_DPN_HCTRL_B1(t_params->port_num);
72 	} else {
73 		addr1 = SDW_DPN_OFFSETCTRL2_B0(t_params->port_num);
74 		addr2 = SDW_DPN_BLOCKCTRL3_B0(t_params->port_num);
75 		addr3 = SDW_DPN_SAMPLECTRL2_B0(t_params->port_num);
76 		addr4 = SDW_DPN_HCTRL_B0(t_params->port_num);
77 	}
78 
79 	/* Program DPN_OffsetCtrl2 registers */
80 	ret = sdw_write(slave, addr1, t_params->offset2);
81 	if (ret < 0) {
82 		dev_err(bus->dev, "DPN_OffsetCtrl2 register write failed\n");
83 		return ret;
84 	}
85 
86 	/* Program DPN_BlockCtrl3 register */
87 	ret = sdw_write(slave, addr2, t_params->blk_pkg_mode);
88 	if (ret < 0) {
89 		dev_err(bus->dev, "DPN_BlockCtrl3 register write failed\n");
90 		return ret;
91 	}
92 
93 	/*
94 	 * Data ports are FULL, SIMPLE and REDUCED. This function handles
95 	 * FULL and REDUCED only and beyond this point only FULL is
96 	 * handled, so bail out if we are not FULL data port type
97 	 */
98 	if (type != SDW_DPN_FULL)
99 		return ret;
100 
101 	/* Program DPN_SampleCtrl2 register */
102 	wbuf = (t_params->sample_interval - 1);
103 	wbuf &= SDW_DPN_SAMPLECTRL_HIGH;
104 	wbuf >>= SDW_REG_SHIFT(SDW_DPN_SAMPLECTRL_HIGH);
105 
106 	ret = sdw_write(slave, addr3, wbuf);
107 	if (ret < 0) {
108 		dev_err(bus->dev, "DPN_SampleCtrl2 register write failed\n");
109 		return ret;
110 	}
111 
112 	/* Program DPN_HCtrl register */
113 	wbuf = t_params->hstart;
114 	wbuf <<= SDW_REG_SHIFT(SDW_DPN_HCTRL_HSTART);
115 	wbuf |= t_params->hstop;
116 
117 	ret = sdw_write(slave, addr4, wbuf);
118 	if (ret < 0)
119 		dev_err(bus->dev, "DPN_HCtrl register write failed\n");
120 
121 	return ret;
122 }
123 
124 static int sdw_program_slave_port_params(struct sdw_bus *bus,
125 					 struct sdw_slave_runtime *s_rt,
126 					 struct sdw_port_runtime *p_rt)
127 {
128 	struct sdw_transport_params *t_params = &p_rt->transport_params;
129 	struct sdw_port_params *p_params = &p_rt->port_params;
130 	struct sdw_slave_prop *slave_prop = &s_rt->slave->prop;
131 	u32 addr1, addr2, addr3, addr4, addr5, addr6;
132 	struct sdw_dpn_prop *dpn_prop;
133 	int ret;
134 	u8 wbuf;
135 
136 	dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave,
137 					  s_rt->direction,
138 					  t_params->port_num);
139 	if (!dpn_prop)
140 		return -EINVAL;
141 
142 	addr1 = SDW_DPN_PORTCTRL(t_params->port_num);
143 	addr2 = SDW_DPN_BLOCKCTRL1(t_params->port_num);
144 
145 	if (bus->params.next_bank) {
146 		addr3 = SDW_DPN_SAMPLECTRL1_B1(t_params->port_num);
147 		addr4 = SDW_DPN_OFFSETCTRL1_B1(t_params->port_num);
148 		addr5 = SDW_DPN_BLOCKCTRL2_B1(t_params->port_num);
149 		addr6 = SDW_DPN_LANECTRL_B1(t_params->port_num);
150 
151 	} else {
152 		addr3 = SDW_DPN_SAMPLECTRL1_B0(t_params->port_num);
153 		addr4 = SDW_DPN_OFFSETCTRL1_B0(t_params->port_num);
154 		addr5 = SDW_DPN_BLOCKCTRL2_B0(t_params->port_num);
155 		addr6 = SDW_DPN_LANECTRL_B0(t_params->port_num);
156 	}
157 
158 	/* Program DPN_PortCtrl register */
159 	wbuf = p_params->data_mode << SDW_REG_SHIFT(SDW_DPN_PORTCTRL_DATAMODE);
160 	wbuf |= p_params->flow_mode;
161 
162 	ret = sdw_update(s_rt->slave, addr1, 0xF, wbuf);
163 	if (ret < 0) {
164 		dev_err(&s_rt->slave->dev,
165 			"DPN_PortCtrl register write failed for port %d\n",
166 			t_params->port_num);
167 		return ret;
168 	}
169 
170 	if (!dpn_prop->read_only_wordlength) {
171 		/* Program DPN_BlockCtrl1 register */
172 		ret = sdw_write(s_rt->slave, addr2, (p_params->bps - 1));
173 		if (ret < 0) {
174 			dev_err(&s_rt->slave->dev,
175 				"DPN_BlockCtrl1 register write failed for port %d\n",
176 				t_params->port_num);
177 			return ret;
178 		}
179 	}
180 
181 	/* Program DPN_SampleCtrl1 register */
182 	wbuf = (t_params->sample_interval - 1) & SDW_DPN_SAMPLECTRL_LOW;
183 	ret = sdw_write(s_rt->slave, addr3, wbuf);
184 	if (ret < 0) {
185 		dev_err(&s_rt->slave->dev,
186 			"DPN_SampleCtrl1 register write failed for port %d\n",
187 			t_params->port_num);
188 		return ret;
189 	}
190 
191 	/* Program DPN_OffsetCtrl1 registers */
192 	ret = sdw_write(s_rt->slave, addr4, t_params->offset1);
193 	if (ret < 0) {
194 		dev_err(&s_rt->slave->dev,
195 			"DPN_OffsetCtrl1 register write failed for port %d\n",
196 			t_params->port_num);
197 		return ret;
198 	}
199 
200 	/* Program DPN_BlockCtrl2 register*/
201 	if (t_params->blk_grp_ctrl_valid) {
202 		ret = sdw_write(s_rt->slave, addr5, t_params->blk_grp_ctrl);
203 		if (ret < 0) {
204 			dev_err(&s_rt->slave->dev,
205 				"DPN_BlockCtrl2 reg write failed for port %d\n",
206 				t_params->port_num);
207 			return ret;
208 		}
209 	}
210 
211 	/* program DPN_LaneCtrl register */
212 	if (slave_prop->lane_control_support) {
213 		ret = sdw_write(s_rt->slave, addr6, t_params->lane_ctrl);
214 		if (ret < 0) {
215 			dev_err(&s_rt->slave->dev,
216 				"DPN_LaneCtrl register write failed for port %d\n",
217 				t_params->port_num);
218 			return ret;
219 		}
220 	}
221 
222 	if (dpn_prop->type != SDW_DPN_SIMPLE) {
223 		ret = _sdw_program_slave_port_params(bus, s_rt->slave,
224 						     t_params, dpn_prop->type);
225 		if (ret < 0)
226 			dev_err(&s_rt->slave->dev,
227 				"Transport reg write failed for port: %d\n",
228 				t_params->port_num);
229 	}
230 
231 	return ret;
232 }
233 
234 static int sdw_program_master_port_params(struct sdw_bus *bus,
235 					  struct sdw_port_runtime *p_rt)
236 {
237 	int ret;
238 
239 	/*
240 	 * we need to set transport and port parameters for the port.
241 	 * Transport parameters refers to the sample interval, offsets and
242 	 * hstart/stop etc of the data. Port parameters refers to word
243 	 * length, flow mode etc of the port
244 	 */
245 	ret = bus->port_ops->dpn_set_port_transport_params(bus,
246 					&p_rt->transport_params,
247 					bus->params.next_bank);
248 	if (ret < 0)
249 		return ret;
250 
251 	return bus->port_ops->dpn_set_port_params(bus,
252 						  &p_rt->port_params,
253 						  bus->params.next_bank);
254 }
255 
256 /**
257  * sdw_program_port_params() - Programs transport parameters of Master(s)
258  * and Slave(s)
259  *
260  * @m_rt: Master stream runtime
261  */
262 static int sdw_program_port_params(struct sdw_master_runtime *m_rt)
263 {
264 	struct sdw_slave_runtime *s_rt = NULL;
265 	struct sdw_bus *bus = m_rt->bus;
266 	struct sdw_port_runtime *p_rt;
267 	int ret = 0;
268 
269 	/* Program transport & port parameters for Slave(s) */
270 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
271 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
272 			ret = sdw_program_slave_port_params(bus, s_rt, p_rt);
273 			if (ret < 0)
274 				return ret;
275 		}
276 	}
277 
278 	/* Program transport & port parameters for Master(s) */
279 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
280 		ret = sdw_program_master_port_params(bus, p_rt);
281 		if (ret < 0)
282 			return ret;
283 	}
284 
285 	return 0;
286 }
287 
288 /**
289  * sdw_enable_disable_slave_ports: Enable/disable slave data port
290  *
291  * @bus: bus instance
292  * @s_rt: slave runtime
293  * @p_rt: port runtime
294  * @en: enable or disable operation
295  *
296  * This function only sets the enable/disable bits in the relevant bank, the
297  * actual enable/disable is done with a bank switch
298  */
299 static int sdw_enable_disable_slave_ports(struct sdw_bus *bus,
300 					  struct sdw_slave_runtime *s_rt,
301 					  struct sdw_port_runtime *p_rt,
302 					  bool en)
303 {
304 	struct sdw_transport_params *t_params = &p_rt->transport_params;
305 	u32 addr;
306 	int ret;
307 
308 	if (bus->params.next_bank)
309 		addr = SDW_DPN_CHANNELEN_B1(p_rt->num);
310 	else
311 		addr = SDW_DPN_CHANNELEN_B0(p_rt->num);
312 
313 	/*
314 	 * Since bus doesn't support sharing a port across two streams,
315 	 * it is safe to reset this register
316 	 */
317 	if (en)
318 		ret = sdw_write(s_rt->slave, addr, p_rt->ch_mask);
319 	else
320 		ret = sdw_write(s_rt->slave, addr, 0x0);
321 
322 	if (ret < 0)
323 		dev_err(&s_rt->slave->dev,
324 			"Slave chn_en reg write failed:%d port:%d\n",
325 			ret, t_params->port_num);
326 
327 	return ret;
328 }
329 
330 static int sdw_enable_disable_master_ports(struct sdw_master_runtime *m_rt,
331 					   struct sdw_port_runtime *p_rt,
332 					   bool en)
333 {
334 	struct sdw_transport_params *t_params = &p_rt->transport_params;
335 	struct sdw_bus *bus = m_rt->bus;
336 	struct sdw_enable_ch enable_ch;
337 	int ret;
338 
339 	enable_ch.port_num = p_rt->num;
340 	enable_ch.ch_mask = p_rt->ch_mask;
341 	enable_ch.enable = en;
342 
343 	/* Perform Master port channel(s) enable/disable */
344 	if (bus->port_ops->dpn_port_enable_ch) {
345 		ret = bus->port_ops->dpn_port_enable_ch(bus,
346 							&enable_ch,
347 							bus->params.next_bank);
348 		if (ret < 0) {
349 			dev_err(bus->dev,
350 				"Master chn_en write failed:%d port:%d\n",
351 				ret, t_params->port_num);
352 			return ret;
353 		}
354 	} else {
355 		dev_err(bus->dev,
356 			"dpn_port_enable_ch not supported, %s failed\n",
357 			en ? "enable" : "disable");
358 		return -EINVAL;
359 	}
360 
361 	return 0;
362 }
363 
364 /**
365  * sdw_enable_disable_ports() - Enable/disable port(s) for Master and
366  * Slave(s)
367  *
368  * @m_rt: Master stream runtime
369  * @en: mode (enable/disable)
370  */
371 static int sdw_enable_disable_ports(struct sdw_master_runtime *m_rt, bool en)
372 {
373 	struct sdw_port_runtime *s_port, *m_port;
374 	struct sdw_slave_runtime *s_rt;
375 	int ret = 0;
376 
377 	/* Enable/Disable Slave port(s) */
378 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
379 		list_for_each_entry(s_port, &s_rt->port_list, port_node) {
380 			ret = sdw_enable_disable_slave_ports(m_rt->bus, s_rt,
381 							     s_port, en);
382 			if (ret < 0)
383 				return ret;
384 		}
385 	}
386 
387 	/* Enable/Disable Master port(s) */
388 	list_for_each_entry(m_port, &m_rt->port_list, port_node) {
389 		ret = sdw_enable_disable_master_ports(m_rt, m_port, en);
390 		if (ret < 0)
391 			return ret;
392 	}
393 
394 	return 0;
395 }
396 
397 static int sdw_do_port_prep(struct sdw_slave_runtime *s_rt,
398 			    struct sdw_prepare_ch prep_ch,
399 			    enum sdw_port_prep_ops cmd)
400 {
401 	const struct sdw_slave_ops *ops = s_rt->slave->ops;
402 	int ret;
403 
404 	if (ops->port_prep) {
405 		ret = ops->port_prep(s_rt->slave, &prep_ch, cmd);
406 		if (ret < 0) {
407 			dev_err(&s_rt->slave->dev,
408 				"Slave Port Prep cmd %d failed: %d\n",
409 				cmd, ret);
410 			return ret;
411 		}
412 	}
413 
414 	return 0;
415 }
416 
417 static int sdw_prep_deprep_slave_ports(struct sdw_bus *bus,
418 				       struct sdw_slave_runtime *s_rt,
419 				       struct sdw_port_runtime *p_rt,
420 				       bool prep)
421 {
422 	struct completion *port_ready;
423 	struct sdw_dpn_prop *dpn_prop;
424 	struct sdw_prepare_ch prep_ch;
425 	unsigned int time_left;
426 	bool intr = false;
427 	int ret = 0, val;
428 	u32 addr;
429 
430 	prep_ch.num = p_rt->num;
431 	prep_ch.ch_mask = p_rt->ch_mask;
432 
433 	dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave,
434 					  s_rt->direction,
435 					  prep_ch.num);
436 	if (!dpn_prop) {
437 		dev_err(bus->dev,
438 			"Slave Port:%d properties not found\n", prep_ch.num);
439 		return -EINVAL;
440 	}
441 
442 	prep_ch.prepare = prep;
443 
444 	prep_ch.bank = bus->params.next_bank;
445 
446 	if (dpn_prop->imp_def_interrupts || !dpn_prop->simple_ch_prep_sm)
447 		intr = true;
448 
449 	/*
450 	 * Enable interrupt before Port prepare.
451 	 * For Port de-prepare, it is assumed that port
452 	 * was prepared earlier
453 	 */
454 	if (prep && intr) {
455 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
456 					     dpn_prop->imp_def_interrupts);
457 		if (ret < 0)
458 			return ret;
459 	}
460 
461 	/* Inform slave about the impending port prepare */
462 	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_PRE_PREP);
463 
464 	/* Prepare Slave port implementing CP_SM */
465 	if (!dpn_prop->simple_ch_prep_sm) {
466 		addr = SDW_DPN_PREPARECTRL(p_rt->num);
467 
468 		if (prep)
469 			ret = sdw_write(s_rt->slave, addr, p_rt->ch_mask);
470 		else
471 			ret = sdw_write(s_rt->slave, addr, 0x0);
472 
473 		if (ret < 0) {
474 			dev_err(&s_rt->slave->dev,
475 				"Slave prep_ctrl reg write failed\n");
476 			return ret;
477 		}
478 
479 		/* Wait for completion on port ready */
480 		port_ready = &s_rt->slave->port_ready[prep_ch.num];
481 		time_left = wait_for_completion_timeout(port_ready,
482 				msecs_to_jiffies(dpn_prop->ch_prep_timeout));
483 
484 		val = sdw_read(s_rt->slave, SDW_DPN_PREPARESTATUS(p_rt->num));
485 		val &= p_rt->ch_mask;
486 		if (!time_left || val) {
487 			dev_err(&s_rt->slave->dev,
488 				"Chn prep failed for port:%d\n", prep_ch.num);
489 			return -ETIMEDOUT;
490 		}
491 	}
492 
493 	/* Inform slaves about ports prepared */
494 	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_POST_PREP);
495 
496 	/* Disable interrupt after Port de-prepare */
497 	if (!prep && intr)
498 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
499 					     dpn_prop->imp_def_interrupts);
500 
501 	return ret;
502 }
503 
504 static int sdw_prep_deprep_master_ports(struct sdw_master_runtime *m_rt,
505 					struct sdw_port_runtime *p_rt,
506 					bool prep)
507 {
508 	struct sdw_transport_params *t_params = &p_rt->transport_params;
509 	struct sdw_bus *bus = m_rt->bus;
510 	const struct sdw_master_port_ops *ops = bus->port_ops;
511 	struct sdw_prepare_ch prep_ch;
512 	int ret = 0;
513 
514 	prep_ch.num = p_rt->num;
515 	prep_ch.ch_mask = p_rt->ch_mask;
516 	prep_ch.prepare = prep; /* Prepare/De-prepare */
517 	prep_ch.bank = bus->params.next_bank;
518 
519 	/* Pre-prepare/Pre-deprepare port(s) */
520 	if (ops->dpn_port_prep) {
521 		ret = ops->dpn_port_prep(bus, &prep_ch);
522 		if (ret < 0) {
523 			dev_err(bus->dev, "Port prepare failed for port:%d\n",
524 				t_params->port_num);
525 			return ret;
526 		}
527 	}
528 
529 	return ret;
530 }
531 
532 /**
533  * sdw_prep_deprep_ports() - Prepare/De-prepare port(s) for Master(s) and
534  * Slave(s)
535  *
536  * @m_rt: Master runtime handle
537  * @prep: Prepare or De-prepare
538  */
539 static int sdw_prep_deprep_ports(struct sdw_master_runtime *m_rt, bool prep)
540 {
541 	struct sdw_slave_runtime *s_rt;
542 	struct sdw_port_runtime *p_rt;
543 	int ret = 0;
544 
545 	/* Prepare/De-prepare Slave port(s) */
546 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
547 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
548 			ret = sdw_prep_deprep_slave_ports(m_rt->bus, s_rt,
549 							  p_rt, prep);
550 			if (ret < 0)
551 				return ret;
552 		}
553 	}
554 
555 	/* Prepare/De-prepare Master port(s) */
556 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
557 		ret = sdw_prep_deprep_master_ports(m_rt, p_rt, prep);
558 		if (ret < 0)
559 			return ret;
560 	}
561 
562 	return ret;
563 }
564 
565 /**
566  * sdw_notify_config() - Notify bus configuration
567  *
568  * @m_rt: Master runtime handle
569  *
570  * This function notifies the Master(s) and Slave(s) of the
571  * new bus configuration.
572  */
573 static int sdw_notify_config(struct sdw_master_runtime *m_rt)
574 {
575 	struct sdw_slave_runtime *s_rt;
576 	struct sdw_bus *bus = m_rt->bus;
577 	struct sdw_slave *slave;
578 	int ret = 0;
579 
580 	if (bus->ops->set_bus_conf) {
581 		ret = bus->ops->set_bus_conf(bus, &bus->params);
582 		if (ret < 0)
583 			return ret;
584 	}
585 
586 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
587 		slave = s_rt->slave;
588 
589 		if (slave->ops->bus_config) {
590 			ret = slave->ops->bus_config(slave, &bus->params);
591 			if (ret < 0) {
592 				dev_err(bus->dev, "Notify Slave: %d failed\n",
593 					slave->dev_num);
594 				return ret;
595 			}
596 		}
597 	}
598 
599 	return ret;
600 }
601 
602 /**
603  * sdw_program_params() - Program transport and port parameters for Master(s)
604  * and Slave(s)
605  *
606  * @bus: SDW bus instance
607  * @prepare: true if sdw_program_params() is called by _prepare.
608  */
609 static int sdw_program_params(struct sdw_bus *bus, bool prepare)
610 {
611 	struct sdw_master_runtime *m_rt;
612 	int ret = 0;
613 
614 	list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) {
615 
616 		/*
617 		 * this loop walks through all master runtimes for a
618 		 * bus, but the ports can only be configured while
619 		 * explicitly preparing a stream or handling an
620 		 * already-prepared stream otherwise.
621 		 */
622 		if (!prepare &&
623 		    m_rt->stream->state == SDW_STREAM_CONFIGURED)
624 			continue;
625 
626 		ret = sdw_program_port_params(m_rt);
627 		if (ret < 0) {
628 			dev_err(bus->dev,
629 				"Program transport params failed: %d\n", ret);
630 			return ret;
631 		}
632 
633 		ret = sdw_notify_config(m_rt);
634 		if (ret < 0) {
635 			dev_err(bus->dev,
636 				"Notify bus config failed: %d\n", ret);
637 			return ret;
638 		}
639 
640 		/* Enable port(s) on alternate bank for all active streams */
641 		if (m_rt->stream->state != SDW_STREAM_ENABLED)
642 			continue;
643 
644 		ret = sdw_enable_disable_ports(m_rt, true);
645 		if (ret < 0) {
646 			dev_err(bus->dev, "Enable channel failed: %d\n", ret);
647 			return ret;
648 		}
649 	}
650 
651 	return ret;
652 }
653 
654 static int sdw_bank_switch(struct sdw_bus *bus, int m_rt_count)
655 {
656 	int col_index, row_index;
657 	bool multi_link;
658 	struct sdw_msg *wr_msg;
659 	u8 *wbuf;
660 	int ret;
661 	u16 addr;
662 
663 	wr_msg = kzalloc(sizeof(*wr_msg), GFP_KERNEL);
664 	if (!wr_msg)
665 		return -ENOMEM;
666 
667 	bus->defer_msg.msg = wr_msg;
668 
669 	wbuf = kzalloc(sizeof(*wbuf), GFP_KERNEL);
670 	if (!wbuf) {
671 		ret = -ENOMEM;
672 		goto error_1;
673 	}
674 
675 	/* Get row and column index to program register */
676 	col_index = sdw_find_col_index(bus->params.col);
677 	row_index = sdw_find_row_index(bus->params.row);
678 	wbuf[0] = col_index | (row_index << 3);
679 
680 	if (bus->params.next_bank)
681 		addr = SDW_SCP_FRAMECTRL_B1;
682 	else
683 		addr = SDW_SCP_FRAMECTRL_B0;
684 
685 	sdw_fill_msg(wr_msg, NULL, addr, 1, SDW_BROADCAST_DEV_NUM,
686 		     SDW_MSG_FLAG_WRITE, wbuf);
687 	wr_msg->ssp_sync = true;
688 
689 	/*
690 	 * Set the multi_link flag only when both the hardware supports
691 	 * and there is a stream handled by multiple masters
692 	 */
693 	multi_link = bus->multi_link && (m_rt_count > 1);
694 
695 	if (multi_link)
696 		ret = sdw_transfer_defer(bus, wr_msg, &bus->defer_msg);
697 	else
698 		ret = sdw_transfer(bus, wr_msg);
699 
700 	if (ret < 0) {
701 		dev_err(bus->dev, "Slave frame_ctrl reg write failed\n");
702 		goto error;
703 	}
704 
705 	if (!multi_link) {
706 		kfree(wr_msg);
707 		kfree(wbuf);
708 		bus->defer_msg.msg = NULL;
709 		bus->params.curr_bank = !bus->params.curr_bank;
710 		bus->params.next_bank = !bus->params.next_bank;
711 	}
712 
713 	return 0;
714 
715 error:
716 	kfree(wbuf);
717 error_1:
718 	kfree(wr_msg);
719 	return ret;
720 }
721 
722 /**
723  * sdw_ml_sync_bank_switch: Multilink register bank switch
724  *
725  * @bus: SDW bus instance
726  *
727  * Caller function should free the buffers on error
728  */
729 static int sdw_ml_sync_bank_switch(struct sdw_bus *bus)
730 {
731 	unsigned long time_left;
732 
733 	if (!bus->multi_link)
734 		return 0;
735 
736 	/* Wait for completion of transfer */
737 	time_left = wait_for_completion_timeout(&bus->defer_msg.complete,
738 						bus->bank_switch_timeout);
739 
740 	if (!time_left) {
741 		dev_err(bus->dev, "Controller Timed out on bank switch\n");
742 		return -ETIMEDOUT;
743 	}
744 
745 	bus->params.curr_bank = !bus->params.curr_bank;
746 	bus->params.next_bank = !bus->params.next_bank;
747 
748 	if (bus->defer_msg.msg) {
749 		kfree(bus->defer_msg.msg->buf);
750 		kfree(bus->defer_msg.msg);
751 	}
752 
753 	return 0;
754 }
755 
756 static int do_bank_switch(struct sdw_stream_runtime *stream)
757 {
758 	struct sdw_master_runtime *m_rt;
759 	const struct sdw_master_ops *ops;
760 	struct sdw_bus *bus;
761 	bool multi_link = false;
762 	int ret = 0;
763 
764 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
765 		bus = m_rt->bus;
766 		ops = bus->ops;
767 
768 		if (bus->multi_link) {
769 			multi_link = true;
770 			mutex_lock(&bus->msg_lock);
771 		}
772 
773 		/* Pre-bank switch */
774 		if (ops->pre_bank_switch) {
775 			ret = ops->pre_bank_switch(bus);
776 			if (ret < 0) {
777 				dev_err(bus->dev,
778 					"Pre bank switch op failed: %d\n", ret);
779 				goto msg_unlock;
780 			}
781 		}
782 
783 		/*
784 		 * Perform Bank switch operation.
785 		 * For multi link cases, the actual bank switch is
786 		 * synchronized across all Masters and happens later as a
787 		 * part of post_bank_switch ops.
788 		 */
789 		ret = sdw_bank_switch(bus, stream->m_rt_count);
790 		if (ret < 0) {
791 			dev_err(bus->dev, "Bank switch failed: %d\n", ret);
792 			goto error;
793 		}
794 	}
795 
796 	/*
797 	 * For multi link cases, it is expected that the bank switch is
798 	 * triggered by the post_bank_switch for the first Master in the list
799 	 * and for the other Masters the post_bank_switch() should return doing
800 	 * nothing.
801 	 */
802 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
803 		bus = m_rt->bus;
804 		ops = bus->ops;
805 
806 		/* Post-bank switch */
807 		if (ops->post_bank_switch) {
808 			ret = ops->post_bank_switch(bus);
809 			if (ret < 0) {
810 				dev_err(bus->dev,
811 					"Post bank switch op failed: %d\n",
812 					ret);
813 				goto error;
814 			}
815 		} else if (bus->multi_link && stream->m_rt_count > 1) {
816 			dev_err(bus->dev,
817 				"Post bank switch ops not implemented\n");
818 			goto error;
819 		}
820 
821 		/* Set the bank switch timeout to default, if not set */
822 		if (!bus->bank_switch_timeout)
823 			bus->bank_switch_timeout = DEFAULT_BANK_SWITCH_TIMEOUT;
824 
825 		/* Check if bank switch was successful */
826 		ret = sdw_ml_sync_bank_switch(bus);
827 		if (ret < 0) {
828 			dev_err(bus->dev,
829 				"multi link bank switch failed: %d\n", ret);
830 			goto error;
831 		}
832 
833 		if (bus->multi_link)
834 			mutex_unlock(&bus->msg_lock);
835 	}
836 
837 	return ret;
838 
839 error:
840 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
841 		bus = m_rt->bus;
842 
843 		kfree(bus->defer_msg.msg->buf);
844 		kfree(bus->defer_msg.msg);
845 	}
846 
847 msg_unlock:
848 
849 	if (multi_link) {
850 		list_for_each_entry(m_rt, &stream->master_list, stream_node) {
851 			bus = m_rt->bus;
852 			if (mutex_is_locked(&bus->msg_lock))
853 				mutex_unlock(&bus->msg_lock);
854 		}
855 	}
856 
857 	return ret;
858 }
859 
860 /**
861  * sdw_release_stream() - Free the assigned stream runtime
862  *
863  * @stream: SoundWire stream runtime
864  *
865  * sdw_release_stream should be called only once per stream
866  */
867 void sdw_release_stream(struct sdw_stream_runtime *stream)
868 {
869 	kfree(stream);
870 }
871 EXPORT_SYMBOL(sdw_release_stream);
872 
873 /**
874  * sdw_alloc_stream() - Allocate and return stream runtime
875  *
876  * @stream_name: SoundWire stream name
877  *
878  * Allocates a SoundWire stream runtime instance.
879  * sdw_alloc_stream should be called only once per stream. Typically
880  * invoked from ALSA/ASoC machine/platform driver.
881  */
882 struct sdw_stream_runtime *sdw_alloc_stream(const char *stream_name)
883 {
884 	struct sdw_stream_runtime *stream;
885 
886 	stream = kzalloc(sizeof(*stream), GFP_KERNEL);
887 	if (!stream)
888 		return NULL;
889 
890 	stream->name = stream_name;
891 	INIT_LIST_HEAD(&stream->master_list);
892 	stream->state = SDW_STREAM_ALLOCATED;
893 	stream->m_rt_count = 0;
894 
895 	return stream;
896 }
897 EXPORT_SYMBOL(sdw_alloc_stream);
898 
899 static struct sdw_master_runtime
900 *sdw_find_master_rt(struct sdw_bus *bus,
901 		    struct sdw_stream_runtime *stream)
902 {
903 	struct sdw_master_runtime *m_rt;
904 
905 	/* Retrieve Bus handle if already available */
906 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
907 		if (m_rt->bus == bus)
908 			return m_rt;
909 	}
910 
911 	return NULL;
912 }
913 
914 /**
915  * sdw_alloc_master_rt() - Allocates and initialize Master runtime handle
916  *
917  * @bus: SDW bus instance
918  * @stream_config: Stream configuration
919  * @stream: Stream runtime handle.
920  *
921  * This function is to be called with bus_lock held.
922  */
923 static struct sdw_master_runtime
924 *sdw_alloc_master_rt(struct sdw_bus *bus,
925 		     struct sdw_stream_config *stream_config,
926 		     struct sdw_stream_runtime *stream)
927 {
928 	struct sdw_master_runtime *m_rt;
929 
930 	/*
931 	 * check if Master is already allocated (as a result of Slave adding
932 	 * it first), if so skip allocation and go to configure
933 	 */
934 	m_rt = sdw_find_master_rt(bus, stream);
935 	if (m_rt)
936 		goto stream_config;
937 
938 	m_rt = kzalloc(sizeof(*m_rt), GFP_KERNEL);
939 	if (!m_rt)
940 		return NULL;
941 
942 	/* Initialization of Master runtime handle */
943 	INIT_LIST_HEAD(&m_rt->port_list);
944 	INIT_LIST_HEAD(&m_rt->slave_rt_list);
945 	list_add_tail(&m_rt->stream_node, &stream->master_list);
946 
947 	list_add_tail(&m_rt->bus_node, &bus->m_rt_list);
948 
949 stream_config:
950 	m_rt->ch_count = stream_config->ch_count;
951 	m_rt->bus = bus;
952 	m_rt->stream = stream;
953 	m_rt->direction = stream_config->direction;
954 
955 	return m_rt;
956 }
957 
958 /**
959  * sdw_alloc_slave_rt() - Allocate and initialize Slave runtime handle.
960  *
961  * @slave: Slave handle
962  * @stream_config: Stream configuration
963  * @stream: Stream runtime handle
964  *
965  * This function is to be called with bus_lock held.
966  */
967 static struct sdw_slave_runtime
968 *sdw_alloc_slave_rt(struct sdw_slave *slave,
969 		    struct sdw_stream_config *stream_config,
970 		    struct sdw_stream_runtime *stream)
971 {
972 	struct sdw_slave_runtime *s_rt;
973 
974 	s_rt = kzalloc(sizeof(*s_rt), GFP_KERNEL);
975 	if (!s_rt)
976 		return NULL;
977 
978 	INIT_LIST_HEAD(&s_rt->port_list);
979 	s_rt->ch_count = stream_config->ch_count;
980 	s_rt->direction = stream_config->direction;
981 	s_rt->slave = slave;
982 
983 	return s_rt;
984 }
985 
986 static void sdw_master_port_release(struct sdw_bus *bus,
987 				    struct sdw_master_runtime *m_rt)
988 {
989 	struct sdw_port_runtime *p_rt, *_p_rt;
990 
991 	list_for_each_entry_safe(p_rt, _p_rt, &m_rt->port_list, port_node) {
992 		list_del(&p_rt->port_node);
993 		kfree(p_rt);
994 	}
995 }
996 
997 static void sdw_slave_port_release(struct sdw_bus *bus,
998 				   struct sdw_slave *slave,
999 				   struct sdw_stream_runtime *stream)
1000 {
1001 	struct sdw_port_runtime *p_rt, *_p_rt;
1002 	struct sdw_master_runtime *m_rt;
1003 	struct sdw_slave_runtime *s_rt;
1004 
1005 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1006 		list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
1007 			if (s_rt->slave != slave)
1008 				continue;
1009 
1010 			list_for_each_entry_safe(p_rt, _p_rt,
1011 						 &s_rt->port_list, port_node) {
1012 				list_del(&p_rt->port_node);
1013 				kfree(p_rt);
1014 			}
1015 		}
1016 	}
1017 }
1018 
1019 /**
1020  * sdw_release_slave_stream() - Free Slave(s) runtime handle
1021  *
1022  * @slave: Slave handle.
1023  * @stream: Stream runtime handle.
1024  *
1025  * This function is to be called with bus_lock held.
1026  */
1027 static void sdw_release_slave_stream(struct sdw_slave *slave,
1028 				     struct sdw_stream_runtime *stream)
1029 {
1030 	struct sdw_slave_runtime *s_rt, *_s_rt;
1031 	struct sdw_master_runtime *m_rt;
1032 
1033 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1034 		/* Retrieve Slave runtime handle */
1035 		list_for_each_entry_safe(s_rt, _s_rt,
1036 					 &m_rt->slave_rt_list, m_rt_node) {
1037 			if (s_rt->slave == slave) {
1038 				list_del(&s_rt->m_rt_node);
1039 				kfree(s_rt);
1040 				return;
1041 			}
1042 		}
1043 	}
1044 }
1045 
1046 /**
1047  * sdw_release_master_stream() - Free Master runtime handle
1048  *
1049  * @m_rt: Master runtime node
1050  * @stream: Stream runtime handle.
1051  *
1052  * This function is to be called with bus_lock held
1053  * It frees the Master runtime handle and associated Slave(s) runtime
1054  * handle. If this is called first then sdw_release_slave_stream() will have
1055  * no effect as Slave(s) runtime handle would already be freed up.
1056  */
1057 static void sdw_release_master_stream(struct sdw_master_runtime *m_rt,
1058 				      struct sdw_stream_runtime *stream)
1059 {
1060 	struct sdw_slave_runtime *s_rt, *_s_rt;
1061 
1062 	list_for_each_entry_safe(s_rt, _s_rt, &m_rt->slave_rt_list, m_rt_node) {
1063 		sdw_slave_port_release(s_rt->slave->bus, s_rt->slave, stream);
1064 		sdw_release_slave_stream(s_rt->slave, stream);
1065 	}
1066 
1067 	list_del(&m_rt->stream_node);
1068 	list_del(&m_rt->bus_node);
1069 	kfree(m_rt);
1070 }
1071 
1072 /**
1073  * sdw_stream_remove_master() - Remove master from sdw_stream
1074  *
1075  * @bus: SDW Bus instance
1076  * @stream: SoundWire stream
1077  *
1078  * This removes and frees port_rt and master_rt from a stream
1079  */
1080 int sdw_stream_remove_master(struct sdw_bus *bus,
1081 			     struct sdw_stream_runtime *stream)
1082 {
1083 	struct sdw_master_runtime *m_rt, *_m_rt;
1084 
1085 	mutex_lock(&bus->bus_lock);
1086 
1087 	list_for_each_entry_safe(m_rt, _m_rt,
1088 				 &stream->master_list, stream_node) {
1089 		if (m_rt->bus != bus)
1090 			continue;
1091 
1092 		sdw_master_port_release(bus, m_rt);
1093 		sdw_release_master_stream(m_rt, stream);
1094 		stream->m_rt_count--;
1095 	}
1096 
1097 	if (list_empty(&stream->master_list))
1098 		stream->state = SDW_STREAM_RELEASED;
1099 
1100 	mutex_unlock(&bus->bus_lock);
1101 
1102 	return 0;
1103 }
1104 EXPORT_SYMBOL(sdw_stream_remove_master);
1105 
1106 /**
1107  * sdw_stream_remove_slave() - Remove slave from sdw_stream
1108  *
1109  * @slave: SDW Slave instance
1110  * @stream: SoundWire stream
1111  *
1112  * This removes and frees port_rt and slave_rt from a stream
1113  */
1114 int sdw_stream_remove_slave(struct sdw_slave *slave,
1115 			    struct sdw_stream_runtime *stream)
1116 {
1117 	mutex_lock(&slave->bus->bus_lock);
1118 
1119 	sdw_slave_port_release(slave->bus, slave, stream);
1120 	sdw_release_slave_stream(slave, stream);
1121 
1122 	mutex_unlock(&slave->bus->bus_lock);
1123 
1124 	return 0;
1125 }
1126 EXPORT_SYMBOL(sdw_stream_remove_slave);
1127 
1128 /**
1129  * sdw_config_stream() - Configure the allocated stream
1130  *
1131  * @dev: SDW device
1132  * @stream: SoundWire stream
1133  * @stream_config: Stream configuration for audio stream
1134  * @is_slave: is API called from Slave or Master
1135  *
1136  * This function is to be called with bus_lock held.
1137  */
1138 static int sdw_config_stream(struct device *dev,
1139 			     struct sdw_stream_runtime *stream,
1140 			     struct sdw_stream_config *stream_config,
1141 			     bool is_slave)
1142 {
1143 	/*
1144 	 * Update the stream rate, channel and bps based on data
1145 	 * source. For more than one data source (multilink),
1146 	 * match the rate, bps, stream type and increment number of channels.
1147 	 *
1148 	 * If rate/bps is zero, it means the values are not set, so skip
1149 	 * comparison and allow the value to be set and stored in stream
1150 	 */
1151 	if (stream->params.rate &&
1152 	    stream->params.rate != stream_config->frame_rate) {
1153 		dev_err(dev, "rate not matching, stream:%s\n", stream->name);
1154 		return -EINVAL;
1155 	}
1156 
1157 	if (stream->params.bps &&
1158 	    stream->params.bps != stream_config->bps) {
1159 		dev_err(dev, "bps not matching, stream:%s\n", stream->name);
1160 		return -EINVAL;
1161 	}
1162 
1163 	stream->type = stream_config->type;
1164 	stream->params.rate = stream_config->frame_rate;
1165 	stream->params.bps = stream_config->bps;
1166 
1167 	/* TODO: Update this check during Device-device support */
1168 	if (is_slave)
1169 		stream->params.ch_count += stream_config->ch_count;
1170 
1171 	return 0;
1172 }
1173 
1174 static int sdw_is_valid_port_range(struct device *dev,
1175 				   struct sdw_port_runtime *p_rt)
1176 {
1177 	if (!SDW_VALID_PORT_RANGE(p_rt->num)) {
1178 		dev_err(dev,
1179 			"SoundWire: Invalid port number :%d\n", p_rt->num);
1180 		return -EINVAL;
1181 	}
1182 
1183 	return 0;
1184 }
1185 
1186 static struct sdw_port_runtime
1187 *sdw_port_alloc(struct device *dev,
1188 		struct sdw_port_config *port_config,
1189 		int port_index)
1190 {
1191 	struct sdw_port_runtime *p_rt;
1192 
1193 	p_rt = kzalloc(sizeof(*p_rt), GFP_KERNEL);
1194 	if (!p_rt)
1195 		return NULL;
1196 
1197 	p_rt->ch_mask = port_config[port_index].ch_mask;
1198 	p_rt->num = port_config[port_index].num;
1199 
1200 	return p_rt;
1201 }
1202 
1203 static int sdw_master_port_config(struct sdw_bus *bus,
1204 				  struct sdw_master_runtime *m_rt,
1205 				  struct sdw_port_config *port_config,
1206 				  unsigned int num_ports)
1207 {
1208 	struct sdw_port_runtime *p_rt;
1209 	int i;
1210 
1211 	/* Iterate for number of ports to perform initialization */
1212 	for (i = 0; i < num_ports; i++) {
1213 		p_rt = sdw_port_alloc(bus->dev, port_config, i);
1214 		if (!p_rt)
1215 			return -ENOMEM;
1216 
1217 		/*
1218 		 * TODO: Check port capabilities for requested
1219 		 * configuration (audio mode support)
1220 		 */
1221 
1222 		list_add_tail(&p_rt->port_node, &m_rt->port_list);
1223 	}
1224 
1225 	return 0;
1226 }
1227 
1228 static int sdw_slave_port_config(struct sdw_slave *slave,
1229 				 struct sdw_slave_runtime *s_rt,
1230 				 struct sdw_port_config *port_config,
1231 				 unsigned int num_config)
1232 {
1233 	struct sdw_port_runtime *p_rt;
1234 	int i, ret;
1235 
1236 	/* Iterate for number of ports to perform initialization */
1237 	for (i = 0; i < num_config; i++) {
1238 		p_rt = sdw_port_alloc(&slave->dev, port_config, i);
1239 		if (!p_rt)
1240 			return -ENOMEM;
1241 
1242 		/*
1243 		 * TODO: Check valid port range as defined by DisCo/
1244 		 * slave
1245 		 */
1246 		ret = sdw_is_valid_port_range(&slave->dev, p_rt);
1247 		if (ret < 0) {
1248 			kfree(p_rt);
1249 			return ret;
1250 		}
1251 
1252 		/*
1253 		 * TODO: Check port capabilities for requested
1254 		 * configuration (audio mode support)
1255 		 */
1256 
1257 		list_add_tail(&p_rt->port_node, &s_rt->port_list);
1258 	}
1259 
1260 	return 0;
1261 }
1262 
1263 /**
1264  * sdw_stream_add_master() - Allocate and add master runtime to a stream
1265  *
1266  * @bus: SDW Bus instance
1267  * @stream_config: Stream configuration for audio stream
1268  * @port_config: Port configuration for audio stream
1269  * @num_ports: Number of ports
1270  * @stream: SoundWire stream
1271  */
1272 int sdw_stream_add_master(struct sdw_bus *bus,
1273 			  struct sdw_stream_config *stream_config,
1274 			  struct sdw_port_config *port_config,
1275 			  unsigned int num_ports,
1276 			  struct sdw_stream_runtime *stream)
1277 {
1278 	struct sdw_master_runtime *m_rt;
1279 	int ret;
1280 
1281 	mutex_lock(&bus->bus_lock);
1282 
1283 	/*
1284 	 * For multi link streams, add the second master only if
1285 	 * the bus supports it.
1286 	 * Check if bus->multi_link is set
1287 	 */
1288 	if (!bus->multi_link && stream->m_rt_count > 0) {
1289 		dev_err(bus->dev,
1290 			"Multilink not supported, link %d\n", bus->link_id);
1291 		ret = -EINVAL;
1292 		goto unlock;
1293 	}
1294 
1295 	m_rt = sdw_alloc_master_rt(bus, stream_config, stream);
1296 	if (!m_rt) {
1297 		dev_err(bus->dev,
1298 			"Master runtime config failed for stream:%s\n",
1299 			stream->name);
1300 		ret = -ENOMEM;
1301 		goto unlock;
1302 	}
1303 
1304 	ret = sdw_config_stream(bus->dev, stream, stream_config, false);
1305 	if (ret)
1306 		goto stream_error;
1307 
1308 	ret = sdw_master_port_config(bus, m_rt, port_config, num_ports);
1309 	if (ret)
1310 		goto stream_error;
1311 
1312 	stream->m_rt_count++;
1313 
1314 	goto unlock;
1315 
1316 stream_error:
1317 	sdw_release_master_stream(m_rt, stream);
1318 unlock:
1319 	mutex_unlock(&bus->bus_lock);
1320 	return ret;
1321 }
1322 EXPORT_SYMBOL(sdw_stream_add_master);
1323 
1324 /**
1325  * sdw_stream_add_slave() - Allocate and add master/slave runtime to a stream
1326  *
1327  * @slave: SDW Slave instance
1328  * @stream_config: Stream configuration for audio stream
1329  * @stream: SoundWire stream
1330  * @port_config: Port configuration for audio stream
1331  * @num_ports: Number of ports
1332  *
1333  * It is expected that Slave is added before adding Master
1334  * to the Stream.
1335  *
1336  */
1337 int sdw_stream_add_slave(struct sdw_slave *slave,
1338 			 struct sdw_stream_config *stream_config,
1339 			 struct sdw_port_config *port_config,
1340 			 unsigned int num_ports,
1341 			 struct sdw_stream_runtime *stream)
1342 {
1343 	struct sdw_slave_runtime *s_rt;
1344 	struct sdw_master_runtime *m_rt;
1345 	int ret;
1346 
1347 	mutex_lock(&slave->bus->bus_lock);
1348 
1349 	/*
1350 	 * If this API is invoked by Slave first then m_rt is not valid.
1351 	 * So, allocate m_rt and add Slave to it.
1352 	 */
1353 	m_rt = sdw_alloc_master_rt(slave->bus, stream_config, stream);
1354 	if (!m_rt) {
1355 		dev_err(&slave->dev,
1356 			"alloc master runtime failed for stream:%s\n",
1357 			stream->name);
1358 		ret = -ENOMEM;
1359 		goto error;
1360 	}
1361 
1362 	s_rt = sdw_alloc_slave_rt(slave, stream_config, stream);
1363 	if (!s_rt) {
1364 		dev_err(&slave->dev,
1365 			"Slave runtime config failed for stream:%s\n",
1366 			stream->name);
1367 		ret = -ENOMEM;
1368 		goto stream_error;
1369 	}
1370 
1371 	ret = sdw_config_stream(&slave->dev, stream, stream_config, true);
1372 	if (ret)
1373 		goto stream_error;
1374 
1375 	list_add_tail(&s_rt->m_rt_node, &m_rt->slave_rt_list);
1376 
1377 	ret = sdw_slave_port_config(slave, s_rt, port_config, num_ports);
1378 	if (ret)
1379 		goto stream_error;
1380 
1381 	/*
1382 	 * Change stream state to CONFIGURED on first Slave add.
1383 	 * Bus is not aware of number of Slave(s) in a stream at this
1384 	 * point so cannot depend on all Slave(s) to be added in order to
1385 	 * change stream state to CONFIGURED.
1386 	 */
1387 	stream->state = SDW_STREAM_CONFIGURED;
1388 	goto error;
1389 
1390 stream_error:
1391 	/*
1392 	 * we hit error so cleanup the stream, release all Slave(s) and
1393 	 * Master runtime
1394 	 */
1395 	sdw_release_master_stream(m_rt, stream);
1396 error:
1397 	mutex_unlock(&slave->bus->bus_lock);
1398 	return ret;
1399 }
1400 EXPORT_SYMBOL(sdw_stream_add_slave);
1401 
1402 /**
1403  * sdw_get_slave_dpn_prop() - Get Slave port capabilities
1404  *
1405  * @slave: Slave handle
1406  * @direction: Data direction.
1407  * @port_num: Port number
1408  */
1409 struct sdw_dpn_prop *sdw_get_slave_dpn_prop(struct sdw_slave *slave,
1410 					    enum sdw_data_direction direction,
1411 					    unsigned int port_num)
1412 {
1413 	struct sdw_dpn_prop *dpn_prop;
1414 	u8 num_ports;
1415 	int i;
1416 
1417 	if (direction == SDW_DATA_DIR_TX) {
1418 		num_ports = hweight32(slave->prop.source_ports);
1419 		dpn_prop = slave->prop.src_dpn_prop;
1420 	} else {
1421 		num_ports = hweight32(slave->prop.sink_ports);
1422 		dpn_prop = slave->prop.sink_dpn_prop;
1423 	}
1424 
1425 	for (i = 0; i < num_ports; i++) {
1426 		if (dpn_prop[i].num == port_num)
1427 			return &dpn_prop[i];
1428 	}
1429 
1430 	return NULL;
1431 }
1432 
1433 /**
1434  * sdw_acquire_bus_lock: Acquire bus lock for all Master runtime(s)
1435  *
1436  * @stream: SoundWire stream
1437  *
1438  * Acquire bus_lock for each of the master runtime(m_rt) part of this
1439  * stream to reconfigure the bus.
1440  * NOTE: This function is called from SoundWire stream ops and is
1441  * expected that a global lock is held before acquiring bus_lock.
1442  */
1443 static void sdw_acquire_bus_lock(struct sdw_stream_runtime *stream)
1444 {
1445 	struct sdw_master_runtime *m_rt;
1446 	struct sdw_bus *bus = NULL;
1447 
1448 	/* Iterate for all Master(s) in Master list */
1449 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1450 		bus = m_rt->bus;
1451 
1452 		mutex_lock(&bus->bus_lock);
1453 	}
1454 }
1455 
1456 /**
1457  * sdw_release_bus_lock: Release bus lock for all Master runtime(s)
1458  *
1459  * @stream: SoundWire stream
1460  *
1461  * Release the previously held bus_lock after reconfiguring the bus.
1462  * NOTE: This function is called from SoundWire stream ops and is
1463  * expected that a global lock is held before releasing bus_lock.
1464  */
1465 static void sdw_release_bus_lock(struct sdw_stream_runtime *stream)
1466 {
1467 	struct sdw_master_runtime *m_rt = NULL;
1468 	struct sdw_bus *bus = NULL;
1469 
1470 	/* Iterate for all Master(s) in Master list */
1471 	list_for_each_entry_reverse(m_rt, &stream->master_list, stream_node) {
1472 		bus = m_rt->bus;
1473 		mutex_unlock(&bus->bus_lock);
1474 	}
1475 }
1476 
1477 static int _sdw_prepare_stream(struct sdw_stream_runtime *stream,
1478 			       bool update_params)
1479 {
1480 	struct sdw_master_runtime *m_rt;
1481 	struct sdw_bus *bus = NULL;
1482 	struct sdw_master_prop *prop;
1483 	struct sdw_bus_params params;
1484 	int ret;
1485 
1486 	/* Prepare  Master(s) and Slave(s) port(s) associated with stream */
1487 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1488 		bus = m_rt->bus;
1489 		prop = &bus->prop;
1490 		memcpy(&params, &bus->params, sizeof(params));
1491 
1492 		/* TODO: Support Asynchronous mode */
1493 		if ((prop->max_clk_freq % stream->params.rate) != 0) {
1494 			dev_err(bus->dev, "Async mode not supported\n");
1495 			return -EINVAL;
1496 		}
1497 
1498 		if (!update_params)
1499 			goto program_params;
1500 
1501 		/* Increment cumulative bus bandwidth */
1502 		/* TODO: Update this during Device-Device support */
1503 		bus->params.bandwidth += m_rt->stream->params.rate *
1504 			m_rt->ch_count * m_rt->stream->params.bps;
1505 
1506 		/* Compute params */
1507 		if (bus->compute_params) {
1508 			ret = bus->compute_params(bus);
1509 			if (ret < 0) {
1510 				dev_err(bus->dev, "Compute params failed: %d",
1511 					ret);
1512 				return ret;
1513 			}
1514 		}
1515 
1516 program_params:
1517 		/* Program params */
1518 		ret = sdw_program_params(bus, true);
1519 		if (ret < 0) {
1520 			dev_err(bus->dev, "Program params failed: %d\n", ret);
1521 			goto restore_params;
1522 		}
1523 	}
1524 
1525 	if (!bus) {
1526 		pr_err("Configuration error in %s\n", __func__);
1527 		return -EINVAL;
1528 	}
1529 
1530 	ret = do_bank_switch(stream);
1531 	if (ret < 0) {
1532 		dev_err(bus->dev, "Bank switch failed: %d\n", ret);
1533 		goto restore_params;
1534 	}
1535 
1536 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1537 		bus = m_rt->bus;
1538 
1539 		/* Prepare port(s) on the new clock configuration */
1540 		ret = sdw_prep_deprep_ports(m_rt, true);
1541 		if (ret < 0) {
1542 			dev_err(bus->dev, "Prepare port(s) failed ret = %d\n",
1543 				ret);
1544 			return ret;
1545 		}
1546 	}
1547 
1548 	stream->state = SDW_STREAM_PREPARED;
1549 
1550 	return ret;
1551 
1552 restore_params:
1553 	memcpy(&bus->params, &params, sizeof(params));
1554 	return ret;
1555 }
1556 
1557 /**
1558  * sdw_prepare_stream() - Prepare SoundWire stream
1559  *
1560  * @stream: Soundwire stream
1561  *
1562  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1563  */
1564 int sdw_prepare_stream(struct sdw_stream_runtime *stream)
1565 {
1566 	bool update_params = true;
1567 	int ret;
1568 
1569 	if (!stream) {
1570 		pr_err("SoundWire: Handle not found for stream\n");
1571 		return -EINVAL;
1572 	}
1573 
1574 	sdw_acquire_bus_lock(stream);
1575 
1576 	if (stream->state == SDW_STREAM_PREPARED) {
1577 		ret = 0;
1578 		goto state_err;
1579 	}
1580 
1581 	if (stream->state != SDW_STREAM_CONFIGURED &&
1582 	    stream->state != SDW_STREAM_DEPREPARED &&
1583 	    stream->state != SDW_STREAM_DISABLED) {
1584 		pr_err("%s: %s: inconsistent state state %d\n",
1585 		       __func__, stream->name, stream->state);
1586 		ret = -EINVAL;
1587 		goto state_err;
1588 	}
1589 
1590 	/*
1591 	 * when the stream is DISABLED, this means sdw_prepare_stream()
1592 	 * is called as a result of an underflow or a resume operation.
1593 	 * In this case, the bus parameters shall not be recomputed, but
1594 	 * still need to be re-applied
1595 	 */
1596 	if (stream->state == SDW_STREAM_DISABLED)
1597 		update_params = false;
1598 
1599 	ret = _sdw_prepare_stream(stream, update_params);
1600 
1601 state_err:
1602 	sdw_release_bus_lock(stream);
1603 	return ret;
1604 }
1605 EXPORT_SYMBOL(sdw_prepare_stream);
1606 
1607 static int _sdw_enable_stream(struct sdw_stream_runtime *stream)
1608 {
1609 	struct sdw_master_runtime *m_rt;
1610 	struct sdw_bus *bus = NULL;
1611 	int ret;
1612 
1613 	/* Enable Master(s) and Slave(s) port(s) associated with stream */
1614 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1615 		bus = m_rt->bus;
1616 
1617 		/* Program params */
1618 		ret = sdw_program_params(bus, false);
1619 		if (ret < 0) {
1620 			dev_err(bus->dev, "Program params failed: %d\n", ret);
1621 			return ret;
1622 		}
1623 
1624 		/* Enable port(s) */
1625 		ret = sdw_enable_disable_ports(m_rt, true);
1626 		if (ret < 0) {
1627 			dev_err(bus->dev,
1628 				"Enable port(s) failed ret: %d\n", ret);
1629 			return ret;
1630 		}
1631 	}
1632 
1633 	if (!bus) {
1634 		pr_err("Configuration error in %s\n", __func__);
1635 		return -EINVAL;
1636 	}
1637 
1638 	ret = do_bank_switch(stream);
1639 	if (ret < 0) {
1640 		dev_err(bus->dev, "Bank switch failed: %d\n", ret);
1641 		return ret;
1642 	}
1643 
1644 	stream->state = SDW_STREAM_ENABLED;
1645 	return 0;
1646 }
1647 
1648 /**
1649  * sdw_enable_stream() - Enable SoundWire stream
1650  *
1651  * @stream: Soundwire stream
1652  *
1653  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1654  */
1655 int sdw_enable_stream(struct sdw_stream_runtime *stream)
1656 {
1657 	int ret;
1658 
1659 	if (!stream) {
1660 		pr_err("SoundWire: Handle not found for stream\n");
1661 		return -EINVAL;
1662 	}
1663 
1664 	sdw_acquire_bus_lock(stream);
1665 
1666 	if (stream->state != SDW_STREAM_PREPARED &&
1667 	    stream->state != SDW_STREAM_DISABLED) {
1668 		pr_err("%s: %s: inconsistent state state %d\n",
1669 		       __func__, stream->name, stream->state);
1670 		ret = -EINVAL;
1671 		goto state_err;
1672 	}
1673 
1674 	ret = _sdw_enable_stream(stream);
1675 
1676 state_err:
1677 	sdw_release_bus_lock(stream);
1678 	return ret;
1679 }
1680 EXPORT_SYMBOL(sdw_enable_stream);
1681 
1682 static int _sdw_disable_stream(struct sdw_stream_runtime *stream)
1683 {
1684 	struct sdw_master_runtime *m_rt;
1685 	int ret;
1686 
1687 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1688 		struct sdw_bus *bus = m_rt->bus;
1689 
1690 		/* Disable port(s) */
1691 		ret = sdw_enable_disable_ports(m_rt, false);
1692 		if (ret < 0) {
1693 			dev_err(bus->dev, "Disable port(s) failed: %d\n", ret);
1694 			return ret;
1695 		}
1696 	}
1697 	stream->state = SDW_STREAM_DISABLED;
1698 
1699 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1700 		struct sdw_bus *bus = m_rt->bus;
1701 
1702 		/* Program params */
1703 		ret = sdw_program_params(bus, false);
1704 		if (ret < 0) {
1705 			dev_err(bus->dev, "Program params failed: %d\n", ret);
1706 			return ret;
1707 		}
1708 	}
1709 
1710 	ret = do_bank_switch(stream);
1711 	if (ret < 0) {
1712 		pr_err("Bank switch failed: %d\n", ret);
1713 		return ret;
1714 	}
1715 
1716 	/* make sure alternate bank (previous current) is also disabled */
1717 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1718 		struct sdw_bus *bus = m_rt->bus;
1719 
1720 		/* Disable port(s) */
1721 		ret = sdw_enable_disable_ports(m_rt, false);
1722 		if (ret < 0) {
1723 			dev_err(bus->dev, "Disable port(s) failed: %d\n", ret);
1724 			return ret;
1725 		}
1726 	}
1727 
1728 	return 0;
1729 }
1730 
1731 /**
1732  * sdw_disable_stream() - Disable SoundWire stream
1733  *
1734  * @stream: Soundwire stream
1735  *
1736  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1737  */
1738 int sdw_disable_stream(struct sdw_stream_runtime *stream)
1739 {
1740 	int ret;
1741 
1742 	if (!stream) {
1743 		pr_err("SoundWire: Handle not found for stream\n");
1744 		return -EINVAL;
1745 	}
1746 
1747 	sdw_acquire_bus_lock(stream);
1748 
1749 	if (stream->state != SDW_STREAM_ENABLED) {
1750 		pr_err("%s: %s: inconsistent state state %d\n",
1751 		       __func__, stream->name, stream->state);
1752 		ret = -EINVAL;
1753 		goto state_err;
1754 	}
1755 
1756 	ret = _sdw_disable_stream(stream);
1757 
1758 state_err:
1759 	sdw_release_bus_lock(stream);
1760 	return ret;
1761 }
1762 EXPORT_SYMBOL(sdw_disable_stream);
1763 
1764 static int _sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1765 {
1766 	struct sdw_master_runtime *m_rt;
1767 	struct sdw_bus *bus;
1768 	int ret = 0;
1769 
1770 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1771 		bus = m_rt->bus;
1772 		/* De-prepare port(s) */
1773 		ret = sdw_prep_deprep_ports(m_rt, false);
1774 		if (ret < 0) {
1775 			dev_err(bus->dev,
1776 				"De-prepare port(s) failed: %d\n", ret);
1777 			return ret;
1778 		}
1779 
1780 		/* TODO: Update this during Device-Device support */
1781 		bus->params.bandwidth -= m_rt->stream->params.rate *
1782 			m_rt->ch_count * m_rt->stream->params.bps;
1783 
1784 		/* Program params */
1785 		ret = sdw_program_params(bus, false);
1786 		if (ret < 0) {
1787 			dev_err(bus->dev, "Program params failed: %d\n", ret);
1788 			return ret;
1789 		}
1790 	}
1791 
1792 	stream->state = SDW_STREAM_DEPREPARED;
1793 	return do_bank_switch(stream);
1794 }
1795 
1796 /**
1797  * sdw_deprepare_stream() - Deprepare SoundWire stream
1798  *
1799  * @stream: Soundwire stream
1800  *
1801  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1802  */
1803 int sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1804 {
1805 	int ret;
1806 
1807 	if (!stream) {
1808 		pr_err("SoundWire: Handle not found for stream\n");
1809 		return -EINVAL;
1810 	}
1811 
1812 	sdw_acquire_bus_lock(stream);
1813 
1814 	if (stream->state != SDW_STREAM_PREPARED &&
1815 	    stream->state != SDW_STREAM_DISABLED) {
1816 		pr_err("%s: %s: inconsistent state state %d\n",
1817 		       __func__, stream->name, stream->state);
1818 		ret = -EINVAL;
1819 		goto state_err;
1820 	}
1821 
1822 	ret = _sdw_deprepare_stream(stream);
1823 
1824 state_err:
1825 	sdw_release_bus_lock(stream);
1826 	return ret;
1827 }
1828 EXPORT_SYMBOL(sdw_deprepare_stream);
1829