xref: /openbmc/linux/drivers/soundwire/stream.c (revision 1804569d)
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 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 cols[SDW_FRAME_COLS] = {2, 4, 6, 8, 10, 12, 14, 16};
29 
30 static int sdw_find_col_index(int col)
31 {
32 	int i;
33 
34 	for (i = 0; i < SDW_FRAME_COLS; i++) {
35 		if (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 
43 static int sdw_find_row_index(int row)
44 {
45 	int i;
46 
47 	for (i = 0; i < SDW_FRAME_ROWS; i++) {
48 		if (rows[i] == row)
49 			return i;
50 	}
51 
52 	pr_warn("Requested row not found, selecting lowest row no: 48\n");
53 	return 0;
54 }
55 static int _sdw_program_slave_port_params(struct sdw_bus *bus,
56 				struct sdw_slave *slave,
57 				struct sdw_transport_params *t_params,
58 				enum sdw_dpn_type type)
59 {
60 	u32 addr1, addr2, addr3, addr4;
61 	int ret;
62 	u16 wbuf;
63 
64 	if (bus->params.next_bank) {
65 		addr1 = SDW_DPN_OFFSETCTRL2_B1(t_params->port_num);
66 		addr2 = SDW_DPN_BLOCKCTRL3_B1(t_params->port_num);
67 		addr3 = SDW_DPN_SAMPLECTRL2_B1(t_params->port_num);
68 		addr4 = SDW_DPN_HCTRL_B1(t_params->port_num);
69 	} else {
70 		addr1 = SDW_DPN_OFFSETCTRL2_B0(t_params->port_num);
71 		addr2 = SDW_DPN_BLOCKCTRL3_B0(t_params->port_num);
72 		addr3 = SDW_DPN_SAMPLECTRL2_B0(t_params->port_num);
73 		addr4 = SDW_DPN_HCTRL_B0(t_params->port_num);
74 	}
75 
76 	/* Program DPN_OffsetCtrl2 registers */
77 	ret = sdw_write(slave, addr1, t_params->offset2);
78 	if (ret < 0) {
79 		dev_err(bus->dev, "DPN_OffsetCtrl2 register write failed");
80 		return ret;
81 	}
82 
83 	/* Program DPN_BlockCtrl3 register */
84 	ret = sdw_write(slave, addr2, t_params->blk_pkg_mode);
85 	if (ret < 0) {
86 		dev_err(bus->dev, "DPN_BlockCtrl3 register write failed");
87 		return ret;
88 	}
89 
90 	/*
91 	 * Data ports are FULL, SIMPLE and REDUCED. This function handles
92 	 * FULL and REDUCED only and and beyond this point only FULL is
93 	 * handled, so bail out if we are not FULL data port type
94 	 */
95 	if (type != SDW_DPN_FULL)
96 		return ret;
97 
98 	/* Program DPN_SampleCtrl2 register */
99 	wbuf = (t_params->sample_interval - 1);
100 	wbuf &= SDW_DPN_SAMPLECTRL_HIGH;
101 	wbuf >>= SDW_REG_SHIFT(SDW_DPN_SAMPLECTRL_HIGH);
102 
103 	ret = sdw_write(slave, addr3, wbuf);
104 	if (ret < 0) {
105 		dev_err(bus->dev, "DPN_SampleCtrl2 register write failed");
106 		return ret;
107 	}
108 
109 	/* Program DPN_HCtrl register */
110 	wbuf = t_params->hstart;
111 	wbuf <<= SDW_REG_SHIFT(SDW_DPN_HCTRL_HSTART);
112 	wbuf |= t_params->hstop;
113 
114 	ret = sdw_write(slave, addr4, wbuf);
115 	if (ret < 0)
116 		dev_err(bus->dev, "DPN_HCtrl register write failed");
117 
118 	return ret;
119 }
120 
121 static int sdw_program_slave_port_params(struct sdw_bus *bus,
122 			struct sdw_slave_runtime *s_rt,
123 			struct sdw_port_runtime *p_rt)
124 {
125 	struct sdw_transport_params *t_params = &p_rt->transport_params;
126 	struct sdw_port_params *p_params = &p_rt->port_params;
127 	struct sdw_slave_prop *slave_prop = &s_rt->slave->prop;
128 	u32 addr1, addr2, addr3, addr4, addr5, addr6;
129 	struct sdw_dpn_prop *dpn_prop;
130 	int ret;
131 	u8 wbuf;
132 
133 	dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave,
134 					s_rt->direction,
135 					t_params->port_num);
136 	if (!dpn_prop)
137 		return -EINVAL;
138 
139 	addr1 = SDW_DPN_PORTCTRL(t_params->port_num);
140 	addr2 = SDW_DPN_BLOCKCTRL1(t_params->port_num);
141 
142 	if (bus->params.next_bank) {
143 		addr3 = SDW_DPN_SAMPLECTRL1_B1(t_params->port_num);
144 		addr4 = SDW_DPN_OFFSETCTRL1_B1(t_params->port_num);
145 		addr5 = SDW_DPN_BLOCKCTRL2_B1(t_params->port_num);
146 		addr6 = SDW_DPN_LANECTRL_B1(t_params->port_num);
147 
148 	} else {
149 		addr3 = SDW_DPN_SAMPLECTRL1_B0(t_params->port_num);
150 		addr4 = SDW_DPN_OFFSETCTRL1_B0(t_params->port_num);
151 		addr5 = SDW_DPN_BLOCKCTRL2_B0(t_params->port_num);
152 		addr6 = SDW_DPN_LANECTRL_B0(t_params->port_num);
153 	}
154 
155 	/* Program DPN_PortCtrl register */
156 	wbuf = p_params->data_mode << SDW_REG_SHIFT(SDW_DPN_PORTCTRL_DATAMODE);
157 	wbuf |= p_params->flow_mode;
158 
159 	ret = sdw_update(s_rt->slave, addr1, 0xF, wbuf);
160 	if (ret < 0) {
161 		dev_err(&s_rt->slave->dev,
162 			"DPN_PortCtrl register write failed for port %d",
163 			t_params->port_num);
164 		return ret;
165 	}
166 
167 	/* Program DPN_BlockCtrl1 register */
168 	ret = sdw_write(s_rt->slave, addr2, (p_params->bps - 1));
169 	if (ret < 0) {
170 		dev_err(&s_rt->slave->dev,
171 			"DPN_BlockCtrl1 register write failed for port %d",
172 			t_params->port_num);
173 		return ret;
174 	}
175 
176 	/* Program DPN_SampleCtrl1 register */
177 	wbuf = (t_params->sample_interval - 1) & SDW_DPN_SAMPLECTRL_LOW;
178 	ret = sdw_write(s_rt->slave, addr3, wbuf);
179 	if (ret < 0) {
180 		dev_err(&s_rt->slave->dev,
181 			"DPN_SampleCtrl1 register write failed for port %d",
182 			t_params->port_num);
183 		return ret;
184 	}
185 
186 	/* Program DPN_OffsetCtrl1 registers */
187 	ret = sdw_write(s_rt->slave, addr4, t_params->offset1);
188 	if (ret < 0) {
189 		dev_err(&s_rt->slave->dev,
190 			"DPN_OffsetCtrl1 register write failed for port %d",
191 			t_params->port_num);
192 		return ret;
193 	}
194 
195 	/* Program DPN_BlockCtrl2 register*/
196 	if (t_params->blk_grp_ctrl_valid) {
197 		ret = sdw_write(s_rt->slave, addr5, t_params->blk_grp_ctrl);
198 		if (ret < 0) {
199 			dev_err(&s_rt->slave->dev,
200 				"DPN_BlockCtrl2 reg write failed for port %d",
201 				t_params->port_num);
202 			return ret;
203 		}
204 	}
205 
206 	/* program DPN_LaneCtrl register */
207 	if (slave_prop->lane_control_support) {
208 		ret = sdw_write(s_rt->slave, addr6, t_params->lane_ctrl);
209 		if (ret < 0) {
210 			dev_err(&s_rt->slave->dev,
211 				"DPN_LaneCtrl register write failed for port %d",
212 				t_params->port_num);
213 			return ret;
214 		}
215 	}
216 
217 	if (dpn_prop->type != SDW_DPN_SIMPLE) {
218 		ret = _sdw_program_slave_port_params(bus, s_rt->slave,
219 						t_params, dpn_prop->type);
220 		if (ret < 0)
221 			dev_err(&s_rt->slave->dev,
222 				"Transport reg write failed for port: %d",
223 				t_params->port_num);
224 	}
225 
226 	return ret;
227 }
228 
229 static int sdw_program_master_port_params(struct sdw_bus *bus,
230 		struct sdw_port_runtime *p_rt)
231 {
232 	int ret;
233 
234 	/*
235 	 * we need to set transport and port parameters for the port.
236 	 * Transport parameters refers to the smaple interval, offsets and
237 	 * hstart/stop etc of the data. Port parameters refers to word
238 	 * length, flow mode etc of the port
239 	 */
240 	ret = bus->port_ops->dpn_set_port_transport_params(bus,
241 					&p_rt->transport_params,
242 					bus->params.next_bank);
243 	if (ret < 0)
244 		return ret;
245 
246 	return bus->port_ops->dpn_set_port_params(bus,
247 				&p_rt->port_params,
248 				bus->params.next_bank);
249 }
250 
251 /**
252  * sdw_program_port_params() - Programs transport parameters of Master(s)
253  * and Slave(s)
254  *
255  * @m_rt: Master stream runtime
256  */
257 static int sdw_program_port_params(struct sdw_master_runtime *m_rt)
258 {
259 	struct sdw_slave_runtime *s_rt = NULL;
260 	struct sdw_bus *bus = m_rt->bus;
261 	struct sdw_port_runtime *p_rt;
262 	int ret = 0;
263 
264 	/* Program transport & port parameters for Slave(s) */
265 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
266 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
267 			ret = sdw_program_slave_port_params(bus, s_rt, p_rt);
268 			if (ret < 0)
269 				return ret;
270 		}
271 	}
272 
273 	/* Program transport & port parameters for Master(s) */
274 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
275 		ret = sdw_program_master_port_params(bus, p_rt);
276 		if (ret < 0)
277 			return ret;
278 	}
279 
280 	return 0;
281 }
282 
283 /**
284  * sdw_enable_disable_slave_ports: Enable/disable slave data port
285  *
286  * @bus: bus instance
287  * @s_rt: slave runtime
288  * @p_rt: port runtime
289  * @en: enable or disable operation
290  *
291  * This function only sets the enable/disable bits in the relevant bank, the
292  * actual enable/disable is done with a bank switch
293  */
294 static int sdw_enable_disable_slave_ports(struct sdw_bus *bus,
295 				struct sdw_slave_runtime *s_rt,
296 				struct sdw_port_runtime *p_rt, bool en)
297 {
298 	struct sdw_transport_params *t_params = &p_rt->transport_params;
299 	u32 addr;
300 	int ret;
301 
302 	if (bus->params.next_bank)
303 		addr = SDW_DPN_CHANNELEN_B1(p_rt->num);
304 	else
305 		addr = SDW_DPN_CHANNELEN_B0(p_rt->num);
306 
307 	/*
308 	 * Since bus doesn't support sharing a port across two streams,
309 	 * it is safe to reset this register
310 	 */
311 	if (en)
312 		ret = sdw_update(s_rt->slave, addr, 0xFF, p_rt->ch_mask);
313 	else
314 		ret = sdw_update(s_rt->slave, addr, 0xFF, 0x0);
315 
316 	if (ret < 0)
317 		dev_err(&s_rt->slave->dev,
318 			"Slave chn_en reg write failed:%d port:%d",
319 			ret, t_params->port_num);
320 
321 	return ret;
322 }
323 
324 static int sdw_enable_disable_master_ports(struct sdw_master_runtime *m_rt,
325 			struct sdw_port_runtime *p_rt, bool en)
326 {
327 	struct sdw_transport_params *t_params = &p_rt->transport_params;
328 	struct sdw_bus *bus = m_rt->bus;
329 	struct sdw_enable_ch enable_ch;
330 	int ret = 0;
331 
332 	enable_ch.port_num = p_rt->num;
333 	enable_ch.ch_mask = p_rt->ch_mask;
334 	enable_ch.enable = en;
335 
336 	/* Perform Master port channel(s) enable/disable */
337 	if (bus->port_ops->dpn_port_enable_ch) {
338 		ret = bus->port_ops->dpn_port_enable_ch(bus,
339 				&enable_ch, bus->params.next_bank);
340 		if (ret < 0) {
341 			dev_err(bus->dev,
342 				"Master chn_en write failed:%d port:%d",
343 				ret, t_params->port_num);
344 			return ret;
345 		}
346 	} else {
347 		dev_err(bus->dev,
348 			"dpn_port_enable_ch not supported, %s failed\n",
349 			en ? "enable" : "disable");
350 		return -EINVAL;
351 	}
352 
353 	return 0;
354 }
355 
356 /**
357  * sdw_enable_disable_ports() - Enable/disable port(s) for Master and
358  * Slave(s)
359  *
360  * @m_rt: Master stream runtime
361  * @en: mode (enable/disable)
362  */
363 static int sdw_enable_disable_ports(struct sdw_master_runtime *m_rt, bool en)
364 {
365 	struct sdw_port_runtime *s_port, *m_port;
366 	struct sdw_slave_runtime *s_rt = NULL;
367 	int ret = 0;
368 
369 	/* Enable/Disable Slave port(s) */
370 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
371 		list_for_each_entry(s_port, &s_rt->port_list, port_node) {
372 			ret = sdw_enable_disable_slave_ports(m_rt->bus, s_rt,
373 							s_port, en);
374 			if (ret < 0)
375 				return ret;
376 		}
377 	}
378 
379 	/* Enable/Disable Master port(s) */
380 	list_for_each_entry(m_port, &m_rt->port_list, port_node) {
381 		ret = sdw_enable_disable_master_ports(m_rt, m_port, en);
382 		if (ret < 0)
383 			return ret;
384 	}
385 
386 	return 0;
387 }
388 
389 static int sdw_do_port_prep(struct sdw_slave_runtime *s_rt,
390 		struct sdw_prepare_ch prep_ch, enum sdw_port_prep_ops cmd)
391 {
392 	const struct sdw_slave_ops *ops = s_rt->slave->ops;
393 	int ret;
394 
395 	if (ops->port_prep) {
396 		ret = ops->port_prep(s_rt->slave, &prep_ch, cmd);
397 		if (ret < 0) {
398 			dev_err(&s_rt->slave->dev,
399 				"Slave Port Prep cmd %d failed: %d", cmd, ret);
400 			return ret;
401 		}
402 	}
403 
404 	return 0;
405 }
406 
407 static int sdw_prep_deprep_slave_ports(struct sdw_bus *bus,
408 			struct sdw_slave_runtime *s_rt,
409 			struct sdw_port_runtime *p_rt, bool prep)
410 {
411 	struct completion *port_ready = NULL;
412 	struct sdw_dpn_prop *dpn_prop;
413 	struct sdw_prepare_ch prep_ch;
414 	unsigned int time_left;
415 	bool intr = false;
416 	int ret = 0, val;
417 	u32 addr;
418 
419 	prep_ch.num = p_rt->num;
420 	prep_ch.ch_mask = p_rt->ch_mask;
421 
422 	dpn_prop = sdw_get_slave_dpn_prop(s_rt->slave,
423 					s_rt->direction,
424 					prep_ch.num);
425 	if (!dpn_prop) {
426 		dev_err(bus->dev,
427 			"Slave Port:%d properties not found", prep_ch.num);
428 		return -EINVAL;
429 	}
430 
431 	prep_ch.prepare = prep;
432 
433 	prep_ch.bank = bus->params.next_bank;
434 
435 	if (dpn_prop->device_interrupts || !dpn_prop->simple_ch_prep_sm)
436 		intr = true;
437 
438 	/*
439 	 * Enable interrupt before Port prepare.
440 	 * For Port de-prepare, it is assumed that port
441 	 * was prepared earlier
442 	 */
443 	if (prep && intr) {
444 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
445 						dpn_prop->device_interrupts);
446 		if (ret < 0)
447 			return ret;
448 	}
449 
450 	/* Inform slave about the impending port prepare */
451 	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_PRE_PREP);
452 
453 	/* Prepare Slave port implementing CP_SM */
454 	if (!dpn_prop->simple_ch_prep_sm) {
455 		addr = SDW_DPN_PREPARECTRL(p_rt->num);
456 
457 		if (prep)
458 			ret = sdw_update(s_rt->slave, addr,
459 					0xFF, p_rt->ch_mask);
460 		else
461 			ret = sdw_update(s_rt->slave, addr, 0xFF, 0x0);
462 
463 		if (ret < 0) {
464 			dev_err(&s_rt->slave->dev,
465 				"Slave prep_ctrl reg write failed");
466 			return ret;
467 		}
468 
469 		/* Wait for completion on port ready */
470 		port_ready = &s_rt->slave->port_ready[prep_ch.num];
471 		time_left = wait_for_completion_timeout(port_ready,
472 				msecs_to_jiffies(dpn_prop->ch_prep_timeout));
473 
474 		val = sdw_read(s_rt->slave, SDW_DPN_PREPARESTATUS(p_rt->num));
475 		val &= p_rt->ch_mask;
476 		if (!time_left || val) {
477 			dev_err(&s_rt->slave->dev,
478 				"Chn prep failed for port:%d", prep_ch.num);
479 			return -ETIMEDOUT;
480 		}
481 	}
482 
483 	/* Inform slaves about ports prepared */
484 	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_POST_PREP);
485 
486 	/* Disable interrupt after Port de-prepare */
487 	if (!prep && intr)
488 		ret = sdw_configure_dpn_intr(s_rt->slave, p_rt->num, prep,
489 						dpn_prop->device_interrupts);
490 
491 	return ret;
492 }
493 
494 static int sdw_prep_deprep_master_ports(struct sdw_master_runtime *m_rt,
495 				struct sdw_port_runtime *p_rt, bool prep)
496 {
497 	struct sdw_transport_params *t_params = &p_rt->transport_params;
498 	struct sdw_bus *bus = m_rt->bus;
499 	const struct sdw_master_port_ops *ops = bus->port_ops;
500 	struct sdw_prepare_ch prep_ch;
501 	int ret = 0;
502 
503 	prep_ch.num = p_rt->num;
504 	prep_ch.ch_mask = p_rt->ch_mask;
505 	prep_ch.prepare = prep; /* Prepare/De-prepare */
506 	prep_ch.bank = bus->params.next_bank;
507 
508 	/* Pre-prepare/Pre-deprepare port(s) */
509 	if (ops->dpn_port_prep) {
510 		ret = ops->dpn_port_prep(bus, &prep_ch);
511 		if (ret < 0) {
512 			dev_err(bus->dev, "Port prepare failed for port:%d",
513 					t_params->port_num);
514 			return ret;
515 		}
516 	}
517 
518 	return ret;
519 }
520 
521 /**
522  * sdw_prep_deprep_ports() - Prepare/De-prepare port(s) for Master(s) and
523  * Slave(s)
524  *
525  * @m_rt: Master runtime handle
526  * @prep: Prepare or De-prepare
527  */
528 static int sdw_prep_deprep_ports(struct sdw_master_runtime *m_rt, bool prep)
529 {
530 	struct sdw_slave_runtime *s_rt = NULL;
531 	struct sdw_port_runtime *p_rt;
532 	int ret = 0;
533 
534 	/* Prepare/De-prepare Slave port(s) */
535 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
536 		list_for_each_entry(p_rt, &s_rt->port_list, port_node) {
537 			ret = sdw_prep_deprep_slave_ports(m_rt->bus, s_rt,
538 							p_rt, prep);
539 			if (ret < 0)
540 				return ret;
541 		}
542 	}
543 
544 	/* Prepare/De-prepare Master port(s) */
545 	list_for_each_entry(p_rt, &m_rt->port_list, port_node) {
546 		ret = sdw_prep_deprep_master_ports(m_rt, p_rt, prep);
547 		if (ret < 0)
548 			return ret;
549 	}
550 
551 	return ret;
552 }
553 
554 /**
555  * sdw_notify_config() - Notify bus configuration
556  *
557  * @m_rt: Master runtime handle
558  *
559  * This function notifies the Master(s) and Slave(s) of the
560  * new bus configuration.
561  */
562 static int sdw_notify_config(struct sdw_master_runtime *m_rt)
563 {
564 	struct sdw_slave_runtime *s_rt;
565 	struct sdw_bus *bus = m_rt->bus;
566 	struct sdw_slave *slave;
567 	int ret = 0;
568 
569 	if (bus->ops->set_bus_conf) {
570 		ret = bus->ops->set_bus_conf(bus, &bus->params);
571 		if (ret < 0)
572 			return ret;
573 	}
574 
575 	list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
576 		slave = s_rt->slave;
577 
578 		if (slave->ops->bus_config) {
579 			ret = slave->ops->bus_config(slave, &bus->params);
580 			if (ret < 0)
581 				dev_err(bus->dev, "Notify Slave: %d failed",
582 								slave->dev_num);
583 			return ret;
584 		}
585 	}
586 
587 	return ret;
588 }
589 
590 /**
591  * sdw_program_params() - Program transport and port parameters for Master(s)
592  * and Slave(s)
593  *
594  * @bus: SDW bus instance
595  */
596 static int sdw_program_params(struct sdw_bus *bus)
597 {
598 	struct sdw_master_runtime *m_rt = NULL;
599 	int ret = 0;
600 
601 	list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) {
602 		ret = sdw_program_port_params(m_rt);
603 		if (ret < 0) {
604 			dev_err(bus->dev,
605 				"Program transport params failed: %d", ret);
606 			return ret;
607 		}
608 
609 		ret = sdw_notify_config(m_rt);
610 		if (ret < 0) {
611 			dev_err(bus->dev, "Notify bus config failed: %d", ret);
612 			return ret;
613 		}
614 
615 		/* Enable port(s) on alternate bank for all active streams */
616 		if (m_rt->stream->state != SDW_STREAM_ENABLED)
617 			continue;
618 
619 		ret = sdw_enable_disable_ports(m_rt, true);
620 		if (ret < 0) {
621 			dev_err(bus->dev, "Enable channel failed: %d", ret);
622 			return ret;
623 		}
624 	}
625 
626 	return ret;
627 }
628 
629 static int sdw_bank_switch(struct sdw_bus *bus, int m_rt_count)
630 {
631 	int col_index, row_index;
632 	bool multi_link;
633 	struct sdw_msg *wr_msg;
634 	u8 *wbuf = NULL;
635 	int ret = 0;
636 	u16 addr;
637 
638 	wr_msg = kzalloc(sizeof(*wr_msg), GFP_KERNEL);
639 	if (!wr_msg)
640 		return -ENOMEM;
641 
642 	bus->defer_msg.msg = wr_msg;
643 
644 	wbuf = kzalloc(sizeof(*wbuf), GFP_KERNEL);
645 	if (!wbuf) {
646 		ret = -ENOMEM;
647 		goto error_1;
648 	}
649 
650 	/* Get row and column index to program register */
651 	col_index = sdw_find_col_index(bus->params.col);
652 	row_index = sdw_find_row_index(bus->params.row);
653 	wbuf[0] = col_index | (row_index << 3);
654 
655 	if (bus->params.next_bank)
656 		addr = SDW_SCP_FRAMECTRL_B1;
657 	else
658 		addr = SDW_SCP_FRAMECTRL_B0;
659 
660 	sdw_fill_msg(wr_msg, NULL, addr, 1, SDW_BROADCAST_DEV_NUM,
661 					SDW_MSG_FLAG_WRITE, wbuf);
662 	wr_msg->ssp_sync = true;
663 
664 	/*
665 	 * Set the multi_link flag only when both the hardware supports
666 	 * and there is a stream handled by multiple masters
667 	 */
668 	multi_link = bus->multi_link && (m_rt_count > 1);
669 
670 	if (multi_link)
671 		ret = sdw_transfer_defer(bus, wr_msg, &bus->defer_msg);
672 	else
673 		ret = sdw_transfer(bus, wr_msg);
674 
675 	if (ret < 0) {
676 		dev_err(bus->dev, "Slave frame_ctrl reg write failed");
677 		goto error;
678 	}
679 
680 	if (!multi_link) {
681 		kfree(wr_msg);
682 		kfree(wbuf);
683 		bus->defer_msg.msg = NULL;
684 		bus->params.curr_bank = !bus->params.curr_bank;
685 		bus->params.next_bank = !bus->params.next_bank;
686 	}
687 
688 	return 0;
689 
690 error:
691 	kfree(wbuf);
692 error_1:
693 	kfree(wr_msg);
694 	return ret;
695 }
696 
697 /**
698  * sdw_ml_sync_bank_switch: Multilink register bank switch
699  *
700  * @bus: SDW bus instance
701  *
702  * Caller function should free the buffers on error
703  */
704 static int sdw_ml_sync_bank_switch(struct sdw_bus *bus)
705 {
706 	unsigned long time_left;
707 
708 	if (!bus->multi_link)
709 		return 0;
710 
711 	/* Wait for completion of transfer */
712 	time_left = wait_for_completion_timeout(&bus->defer_msg.complete,
713 						bus->bank_switch_timeout);
714 
715 	if (!time_left) {
716 		dev_err(bus->dev, "Controller Timed out on bank switch");
717 		return -ETIMEDOUT;
718 	}
719 
720 	bus->params.curr_bank = !bus->params.curr_bank;
721 	bus->params.next_bank = !bus->params.next_bank;
722 
723 	if (bus->defer_msg.msg) {
724 		kfree(bus->defer_msg.msg->buf);
725 		kfree(bus->defer_msg.msg);
726 	}
727 
728 	return 0;
729 }
730 
731 static int do_bank_switch(struct sdw_stream_runtime *stream)
732 {
733 	struct sdw_master_runtime *m_rt = NULL;
734 	const struct sdw_master_ops *ops;
735 	struct sdw_bus *bus = NULL;
736 	bool multi_link = false;
737 	int ret = 0;
738 
739 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
740 		bus = m_rt->bus;
741 		ops = bus->ops;
742 
743 		if (bus->multi_link) {
744 			multi_link = true;
745 			mutex_lock(&bus->msg_lock);
746 		}
747 
748 		/* Pre-bank switch */
749 		if (ops->pre_bank_switch) {
750 			ret = ops->pre_bank_switch(bus);
751 			if (ret < 0) {
752 				dev_err(bus->dev,
753 					"Pre bank switch op failed: %d", ret);
754 				goto msg_unlock;
755 			}
756 		}
757 
758 		/*
759 		 * Perform Bank switch operation.
760 		 * For multi link cases, the actual bank switch is
761 		 * synchronized across all Masters and happens later as a
762 		 * part of post_bank_switch ops.
763 		 */
764 		ret = sdw_bank_switch(bus, stream->m_rt_count);
765 		if (ret < 0) {
766 			dev_err(bus->dev, "Bank switch failed: %d", ret);
767 			goto error;
768 
769 		}
770 	}
771 
772 	/*
773 	 * For multi link cases, it is expected that the bank switch is
774 	 * triggered by the post_bank_switch for the first Master in the list
775 	 * and for the other Masters the post_bank_switch() should return doing
776 	 * nothing.
777 	 */
778 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
779 		bus = m_rt->bus;
780 		ops = bus->ops;
781 
782 		/* Post-bank switch */
783 		if (ops->post_bank_switch) {
784 			ret = ops->post_bank_switch(bus);
785 			if (ret < 0) {
786 				dev_err(bus->dev,
787 					"Post bank switch op failed: %d", ret);
788 				goto error;
789 			}
790 		} else if (bus->multi_link && stream->m_rt_count > 1) {
791 			dev_err(bus->dev,
792 				"Post bank switch ops not implemented");
793 			goto error;
794 		}
795 
796 		/* Set the bank switch timeout to default, if not set */
797 		if (!bus->bank_switch_timeout)
798 			bus->bank_switch_timeout = DEFAULT_BANK_SWITCH_TIMEOUT;
799 
800 		/* Check if bank switch was successful */
801 		ret = sdw_ml_sync_bank_switch(bus);
802 		if (ret < 0) {
803 			dev_err(bus->dev,
804 				"multi link bank switch failed: %d", ret);
805 			goto error;
806 		}
807 
808 		mutex_unlock(&bus->msg_lock);
809 	}
810 
811 	return ret;
812 
813 error:
814 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
815 
816 		bus = m_rt->bus;
817 
818 		kfree(bus->defer_msg.msg->buf);
819 		kfree(bus->defer_msg.msg);
820 	}
821 
822 msg_unlock:
823 
824 	if (multi_link) {
825 		list_for_each_entry(m_rt, &stream->master_list, stream_node) {
826 			bus = m_rt->bus;
827 			if (mutex_is_locked(&bus->msg_lock))
828 				mutex_unlock(&bus->msg_lock);
829 		}
830 	}
831 
832 	return ret;
833 }
834 
835 /**
836  * sdw_release_stream() - Free the assigned stream runtime
837  *
838  * @stream: SoundWire stream runtime
839  *
840  * sdw_release_stream should be called only once per stream
841  */
842 void sdw_release_stream(struct sdw_stream_runtime *stream)
843 {
844 	kfree(stream);
845 }
846 EXPORT_SYMBOL(sdw_release_stream);
847 
848 /**
849  * sdw_alloc_stream() - Allocate and return stream runtime
850  *
851  * @stream_name: SoundWire stream name
852  *
853  * Allocates a SoundWire stream runtime instance.
854  * sdw_alloc_stream should be called only once per stream. Typically
855  * invoked from ALSA/ASoC machine/platform driver.
856  */
857 struct sdw_stream_runtime *sdw_alloc_stream(char *stream_name)
858 {
859 	struct sdw_stream_runtime *stream;
860 
861 	stream = kzalloc(sizeof(*stream), GFP_KERNEL);
862 	if (!stream)
863 		return NULL;
864 
865 	stream->name = stream_name;
866 	INIT_LIST_HEAD(&stream->master_list);
867 	stream->state = SDW_STREAM_ALLOCATED;
868 	stream->m_rt_count = 0;
869 
870 	return stream;
871 }
872 EXPORT_SYMBOL(sdw_alloc_stream);
873 
874 static struct sdw_master_runtime
875 *sdw_find_master_rt(struct sdw_bus *bus,
876 			struct sdw_stream_runtime *stream)
877 {
878 	struct sdw_master_runtime *m_rt = NULL;
879 
880 	/* Retrieve Bus handle if already available */
881 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
882 		if (m_rt->bus == bus)
883 			return m_rt;
884 	}
885 
886 	return NULL;
887 }
888 
889 /**
890  * sdw_alloc_master_rt() - Allocates and initialize Master runtime handle
891  *
892  * @bus: SDW bus instance
893  * @stream_config: Stream configuration
894  * @stream: Stream runtime handle.
895  *
896  * This function is to be called with bus_lock held.
897  */
898 static struct sdw_master_runtime
899 *sdw_alloc_master_rt(struct sdw_bus *bus,
900 			struct sdw_stream_config *stream_config,
901 			struct sdw_stream_runtime *stream)
902 {
903 	struct sdw_master_runtime *m_rt;
904 
905 	/*
906 	 * check if Master is already allocated (as a result of Slave adding
907 	 * it first), if so skip allocation and go to configure
908 	 */
909 	m_rt = sdw_find_master_rt(bus, stream);
910 	if (m_rt)
911 		goto stream_config;
912 
913 	m_rt = kzalloc(sizeof(*m_rt), GFP_KERNEL);
914 	if (!m_rt)
915 		return NULL;
916 
917 	/* Initialization of Master runtime handle */
918 	INIT_LIST_HEAD(&m_rt->port_list);
919 	INIT_LIST_HEAD(&m_rt->slave_rt_list);
920 	list_add_tail(&m_rt->stream_node, &stream->master_list);
921 
922 	list_add_tail(&m_rt->bus_node, &bus->m_rt_list);
923 
924 stream_config:
925 	m_rt->ch_count = stream_config->ch_count;
926 	m_rt->bus = bus;
927 	m_rt->stream = stream;
928 	m_rt->direction = stream_config->direction;
929 
930 	return m_rt;
931 }
932 
933 /**
934  * sdw_alloc_slave_rt() - Allocate and initialize Slave runtime handle.
935  *
936  * @slave: Slave handle
937  * @stream_config: Stream configuration
938  * @stream: Stream runtime handle
939  *
940  * This function is to be called with bus_lock held.
941  */
942 static struct sdw_slave_runtime
943 *sdw_alloc_slave_rt(struct sdw_slave *slave,
944 			struct sdw_stream_config *stream_config,
945 			struct sdw_stream_runtime *stream)
946 {
947 	struct sdw_slave_runtime *s_rt = NULL;
948 
949 	s_rt = kzalloc(sizeof(*s_rt), GFP_KERNEL);
950 	if (!s_rt)
951 		return NULL;
952 
953 	INIT_LIST_HEAD(&s_rt->port_list);
954 	s_rt->ch_count = stream_config->ch_count;
955 	s_rt->direction = stream_config->direction;
956 	s_rt->slave = slave;
957 
958 	return s_rt;
959 }
960 
961 static void sdw_master_port_release(struct sdw_bus *bus,
962 			struct sdw_master_runtime *m_rt)
963 {
964 	struct sdw_port_runtime *p_rt, *_p_rt;
965 
966 	list_for_each_entry_safe(p_rt, _p_rt,
967 			&m_rt->port_list, port_node) {
968 		list_del(&p_rt->port_node);
969 		kfree(p_rt);
970 	}
971 }
972 
973 static void sdw_slave_port_release(struct sdw_bus *bus,
974 			struct sdw_slave *slave,
975 			struct sdw_stream_runtime *stream)
976 {
977 	struct sdw_port_runtime *p_rt, *_p_rt;
978 	struct sdw_master_runtime *m_rt;
979 	struct sdw_slave_runtime *s_rt;
980 
981 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
982 		list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) {
983 
984 			if (s_rt->slave != slave)
985 				continue;
986 
987 			list_for_each_entry_safe(p_rt, _p_rt,
988 					&s_rt->port_list, port_node) {
989 
990 				list_del(&p_rt->port_node);
991 				kfree(p_rt);
992 			}
993 		}
994 	}
995 }
996 
997 /**
998  * sdw_release_slave_stream() - Free Slave(s) runtime handle
999  *
1000  * @slave: Slave handle.
1001  * @stream: Stream runtime handle.
1002  *
1003  * This function is to be called with bus_lock held.
1004  */
1005 static void sdw_release_slave_stream(struct sdw_slave *slave,
1006 			struct sdw_stream_runtime *stream)
1007 {
1008 	struct sdw_slave_runtime *s_rt, *_s_rt;
1009 	struct sdw_master_runtime *m_rt;
1010 
1011 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1012 		/* Retrieve Slave runtime handle */
1013 		list_for_each_entry_safe(s_rt, _s_rt,
1014 					&m_rt->slave_rt_list, m_rt_node) {
1015 
1016 			if (s_rt->slave == slave) {
1017 				list_del(&s_rt->m_rt_node);
1018 				kfree(s_rt);
1019 				return;
1020 			}
1021 		}
1022 	}
1023 }
1024 
1025 /**
1026  * sdw_release_master_stream() - Free Master runtime handle
1027  *
1028  * @m_rt: Master runtime node
1029  * @stream: Stream runtime handle.
1030  *
1031  * This function is to be called with bus_lock held
1032  * It frees the Master runtime handle and associated Slave(s) runtime
1033  * handle. If this is called first then sdw_release_slave_stream() will have
1034  * no effect as Slave(s) runtime handle would already be freed up.
1035  */
1036 static void sdw_release_master_stream(struct sdw_master_runtime *m_rt,
1037 			struct sdw_stream_runtime *stream)
1038 {
1039 	struct sdw_slave_runtime *s_rt, *_s_rt;
1040 
1041 	list_for_each_entry_safe(s_rt, _s_rt, &m_rt->slave_rt_list, m_rt_node) {
1042 		sdw_slave_port_release(s_rt->slave->bus, s_rt->slave, stream);
1043 		sdw_release_slave_stream(s_rt->slave, stream);
1044 	}
1045 
1046 	list_del(&m_rt->stream_node);
1047 	list_del(&m_rt->bus_node);
1048 	kfree(m_rt);
1049 }
1050 
1051 /**
1052  * sdw_stream_remove_master() - Remove master from sdw_stream
1053  *
1054  * @bus: SDW Bus instance
1055  * @stream: SoundWire stream
1056  *
1057  * This removes and frees port_rt and master_rt from a stream
1058  */
1059 int sdw_stream_remove_master(struct sdw_bus *bus,
1060 		struct sdw_stream_runtime *stream)
1061 {
1062 	struct sdw_master_runtime *m_rt, *_m_rt;
1063 
1064 	mutex_lock(&bus->bus_lock);
1065 
1066 	list_for_each_entry_safe(m_rt, _m_rt,
1067 			&stream->master_list, stream_node) {
1068 
1069 		if (m_rt->bus != bus)
1070 			continue;
1071 
1072 		sdw_master_port_release(bus, m_rt);
1073 		sdw_release_master_stream(m_rt, stream);
1074 		stream->m_rt_count--;
1075 	}
1076 
1077 	if (list_empty(&stream->master_list))
1078 		stream->state = SDW_STREAM_RELEASED;
1079 
1080 	mutex_unlock(&bus->bus_lock);
1081 
1082 	return 0;
1083 }
1084 EXPORT_SYMBOL(sdw_stream_remove_master);
1085 
1086 /**
1087  * sdw_stream_remove_slave() - Remove slave from sdw_stream
1088  *
1089  * @slave: SDW Slave instance
1090  * @stream: SoundWire stream
1091  *
1092  * This removes and frees port_rt and slave_rt from a stream
1093  */
1094 int sdw_stream_remove_slave(struct sdw_slave *slave,
1095 		struct sdw_stream_runtime *stream)
1096 {
1097 	mutex_lock(&slave->bus->bus_lock);
1098 
1099 	sdw_slave_port_release(slave->bus, slave, stream);
1100 	sdw_release_slave_stream(slave, stream);
1101 
1102 	mutex_unlock(&slave->bus->bus_lock);
1103 
1104 	return 0;
1105 }
1106 EXPORT_SYMBOL(sdw_stream_remove_slave);
1107 
1108 /**
1109  * sdw_config_stream() - Configure the allocated stream
1110  *
1111  * @dev: SDW device
1112  * @stream: SoundWire stream
1113  * @stream_config: Stream configuration for audio stream
1114  * @is_slave: is API called from Slave or Master
1115  *
1116  * This function is to be called with bus_lock held.
1117  */
1118 static int sdw_config_stream(struct device *dev,
1119 		struct sdw_stream_runtime *stream,
1120 		struct sdw_stream_config *stream_config, bool is_slave)
1121 {
1122 	/*
1123 	 * Update the stream rate, channel and bps based on data
1124 	 * source. For more than one data source (multilink),
1125 	 * match the rate, bps, stream type and increment number of channels.
1126 	 *
1127 	 * If rate/bps is zero, it means the values are not set, so skip
1128 	 * comparison and allow the value to be set and stored in stream
1129 	 */
1130 	if (stream->params.rate &&
1131 			stream->params.rate != stream_config->frame_rate) {
1132 		dev_err(dev, "rate not matching, stream:%s", stream->name);
1133 		return -EINVAL;
1134 	}
1135 
1136 	if (stream->params.bps &&
1137 			stream->params.bps != stream_config->bps) {
1138 		dev_err(dev, "bps not matching, stream:%s", stream->name);
1139 		return -EINVAL;
1140 	}
1141 
1142 	stream->type = stream_config->type;
1143 	stream->params.rate = stream_config->frame_rate;
1144 	stream->params.bps = stream_config->bps;
1145 
1146 	/* TODO: Update this check during Device-device support */
1147 	if (is_slave)
1148 		stream->params.ch_count += stream_config->ch_count;
1149 
1150 	return 0;
1151 }
1152 
1153 static int sdw_is_valid_port_range(struct device *dev,
1154 				struct sdw_port_runtime *p_rt)
1155 {
1156 	if (!SDW_VALID_PORT_RANGE(p_rt->num)) {
1157 		dev_err(dev,
1158 			"SoundWire: Invalid port number :%d", p_rt->num);
1159 		return -EINVAL;
1160 	}
1161 
1162 	return 0;
1163 }
1164 
1165 static struct sdw_port_runtime *sdw_port_alloc(struct device *dev,
1166 				struct sdw_port_config *port_config,
1167 				int port_index)
1168 {
1169 	struct sdw_port_runtime *p_rt;
1170 
1171 	p_rt = kzalloc(sizeof(*p_rt), GFP_KERNEL);
1172 	if (!p_rt)
1173 		return NULL;
1174 
1175 	p_rt->ch_mask = port_config[port_index].ch_mask;
1176 	p_rt->num = port_config[port_index].num;
1177 
1178 	return p_rt;
1179 }
1180 
1181 static int sdw_master_port_config(struct sdw_bus *bus,
1182 			struct sdw_master_runtime *m_rt,
1183 			struct sdw_port_config *port_config,
1184 			unsigned int num_ports)
1185 {
1186 	struct sdw_port_runtime *p_rt;
1187 	int i;
1188 
1189 	/* Iterate for number of ports to perform initialization */
1190 	for (i = 0; i < num_ports; i++) {
1191 		p_rt = sdw_port_alloc(bus->dev, port_config, i);
1192 		if (!p_rt)
1193 			return -ENOMEM;
1194 
1195 		/*
1196 		 * TODO: Check port capabilities for requested
1197 		 * configuration (audio mode support)
1198 		 */
1199 
1200 		list_add_tail(&p_rt->port_node, &m_rt->port_list);
1201 	}
1202 
1203 	return 0;
1204 }
1205 
1206 static int sdw_slave_port_config(struct sdw_slave *slave,
1207 			struct sdw_slave_runtime *s_rt,
1208 			struct sdw_port_config *port_config,
1209 			unsigned int num_config)
1210 {
1211 	struct sdw_port_runtime *p_rt;
1212 	int i, ret;
1213 
1214 	/* Iterate for number of ports to perform initialization */
1215 	for (i = 0; i < num_config; i++) {
1216 		p_rt = sdw_port_alloc(&slave->dev, port_config, i);
1217 		if (!p_rt)
1218 			return -ENOMEM;
1219 
1220 		/*
1221 		 * TODO: Check valid port range as defined by DisCo/
1222 		 * slave
1223 		 */
1224 		ret = sdw_is_valid_port_range(&slave->dev, p_rt);
1225 		if (ret < 0) {
1226 			kfree(p_rt);
1227 			return ret;
1228 		}
1229 
1230 		/*
1231 		 * TODO: Check port capabilities for requested
1232 		 * configuration (audio mode support)
1233 		 */
1234 
1235 		list_add_tail(&p_rt->port_node, &s_rt->port_list);
1236 	}
1237 
1238 	return 0;
1239 }
1240 
1241 /**
1242  * sdw_stream_add_master() - Allocate and add master runtime to a stream
1243  *
1244  * @bus: SDW Bus instance
1245  * @stream_config: Stream configuration for audio stream
1246  * @port_config: Port configuration for audio stream
1247  * @num_ports: Number of ports
1248  * @stream: SoundWire stream
1249  */
1250 int sdw_stream_add_master(struct sdw_bus *bus,
1251 		struct sdw_stream_config *stream_config,
1252 		struct sdw_port_config *port_config,
1253 		unsigned int num_ports,
1254 		struct sdw_stream_runtime *stream)
1255 {
1256 	struct sdw_master_runtime *m_rt = NULL;
1257 	int ret;
1258 
1259 	mutex_lock(&bus->bus_lock);
1260 
1261 	/*
1262 	 * For multi link streams, add the second master only if
1263 	 * the bus supports it.
1264 	 * Check if bus->multi_link is set
1265 	 */
1266 	if (!bus->multi_link && stream->m_rt_count > 0) {
1267 		dev_err(bus->dev,
1268 			"Multilink not supported, link %d", bus->link_id);
1269 		ret = -EINVAL;
1270 		goto unlock;
1271 	}
1272 
1273 	m_rt = sdw_alloc_master_rt(bus, stream_config, stream);
1274 	if (!m_rt) {
1275 		dev_err(bus->dev,
1276 				"Master runtime config failed for stream:%s",
1277 				stream->name);
1278 		ret = -ENOMEM;
1279 		goto unlock;
1280 	}
1281 
1282 	ret = sdw_config_stream(bus->dev, stream, stream_config, false);
1283 	if (ret)
1284 		goto stream_error;
1285 
1286 	ret = sdw_master_port_config(bus, m_rt, port_config, num_ports);
1287 	if (ret)
1288 		goto stream_error;
1289 
1290 	stream->m_rt_count++;
1291 
1292 	goto unlock;
1293 
1294 stream_error:
1295 	sdw_release_master_stream(m_rt, stream);
1296 unlock:
1297 	mutex_unlock(&bus->bus_lock);
1298 	return ret;
1299 }
1300 EXPORT_SYMBOL(sdw_stream_add_master);
1301 
1302 /**
1303  * sdw_stream_add_slave() - Allocate and add master/slave runtime to a stream
1304  *
1305  * @slave: SDW Slave instance
1306  * @stream_config: Stream configuration for audio stream
1307  * @stream: SoundWire stream
1308  * @port_config: Port configuration for audio stream
1309  * @num_ports: Number of ports
1310  *
1311  * It is expected that Slave is added before adding Master
1312  * to the Stream.
1313  *
1314  */
1315 int sdw_stream_add_slave(struct sdw_slave *slave,
1316 		struct sdw_stream_config *stream_config,
1317 		struct sdw_port_config *port_config,
1318 		unsigned int num_ports,
1319 		struct sdw_stream_runtime *stream)
1320 {
1321 	struct sdw_slave_runtime *s_rt;
1322 	struct sdw_master_runtime *m_rt;
1323 	int ret;
1324 
1325 	mutex_lock(&slave->bus->bus_lock);
1326 
1327 	/*
1328 	 * If this API is invoked by Slave first then m_rt is not valid.
1329 	 * So, allocate m_rt and add Slave to it.
1330 	 */
1331 	m_rt = sdw_alloc_master_rt(slave->bus, stream_config, stream);
1332 	if (!m_rt) {
1333 		dev_err(&slave->dev,
1334 				"alloc master runtime failed for stream:%s",
1335 				stream->name);
1336 		ret = -ENOMEM;
1337 		goto error;
1338 	}
1339 
1340 	s_rt = sdw_alloc_slave_rt(slave, stream_config, stream);
1341 	if (!s_rt) {
1342 		dev_err(&slave->dev,
1343 				"Slave runtime config failed for stream:%s",
1344 				stream->name);
1345 		ret = -ENOMEM;
1346 		goto stream_error;
1347 	}
1348 
1349 	ret = sdw_config_stream(&slave->dev, stream, stream_config, true);
1350 	if (ret)
1351 		goto stream_error;
1352 
1353 	list_add_tail(&s_rt->m_rt_node, &m_rt->slave_rt_list);
1354 
1355 	ret = sdw_slave_port_config(slave, s_rt, port_config, num_ports);
1356 	if (ret)
1357 		goto stream_error;
1358 
1359 	/*
1360 	 * Change stream state to CONFIGURED on first Slave add.
1361 	 * Bus is not aware of number of Slave(s) in a stream at this
1362 	 * point so cannot depend on all Slave(s) to be added in order to
1363 	 * change stream state to CONFIGURED.
1364 	 */
1365 	stream->state = SDW_STREAM_CONFIGURED;
1366 	goto error;
1367 
1368 stream_error:
1369 	/*
1370 	 * we hit error so cleanup the stream, release all Slave(s) and
1371 	 * Master runtime
1372 	 */
1373 	sdw_release_master_stream(m_rt, stream);
1374 error:
1375 	mutex_unlock(&slave->bus->bus_lock);
1376 	return ret;
1377 }
1378 EXPORT_SYMBOL(sdw_stream_add_slave);
1379 
1380 /**
1381  * sdw_get_slave_dpn_prop() - Get Slave port capabilities
1382  *
1383  * @slave: Slave handle
1384  * @direction: Data direction.
1385  * @port_num: Port number
1386  */
1387 struct sdw_dpn_prop *sdw_get_slave_dpn_prop(struct sdw_slave *slave,
1388 				enum sdw_data_direction direction,
1389 				unsigned int port_num)
1390 {
1391 	struct sdw_dpn_prop *dpn_prop;
1392 	u8 num_ports;
1393 	int i;
1394 
1395 	if (direction == SDW_DATA_DIR_TX) {
1396 		num_ports = hweight32(slave->prop.source_ports);
1397 		dpn_prop = slave->prop.src_dpn_prop;
1398 	} else {
1399 		num_ports = hweight32(slave->prop.sink_ports);
1400 		dpn_prop = slave->prop.sink_dpn_prop;
1401 	}
1402 
1403 	for (i = 0; i < num_ports; i++) {
1404 		dpn_prop = &dpn_prop[i];
1405 
1406 		if (dpn_prop->num == port_num)
1407 			return &dpn_prop[i];
1408 	}
1409 
1410 	return NULL;
1411 }
1412 
1413 /**
1414  * sdw_acquire_bus_lock: Acquire bus lock for all Master runtime(s)
1415  *
1416  * @stream: SoundWire stream
1417  *
1418  * Acquire bus_lock for each of the master runtime(m_rt) part of this
1419  * stream to reconfigure the bus.
1420  * NOTE: This function is called from SoundWire stream ops and is
1421  * expected that a global lock is held before acquiring bus_lock.
1422  */
1423 static void sdw_acquire_bus_lock(struct sdw_stream_runtime *stream)
1424 {
1425 	struct sdw_master_runtime *m_rt = NULL;
1426 	struct sdw_bus *bus = NULL;
1427 
1428 	/* Iterate for all Master(s) in Master list */
1429 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1430 		bus = m_rt->bus;
1431 
1432 		mutex_lock(&bus->bus_lock);
1433 	}
1434 }
1435 
1436 /**
1437  * sdw_release_bus_lock: Release bus lock for all Master runtime(s)
1438  *
1439  * @stream: SoundWire stream
1440  *
1441  * Release the previously held bus_lock after reconfiguring the bus.
1442  * NOTE: This function is called from SoundWire stream ops and is
1443  * expected that a global lock is held before releasing bus_lock.
1444  */
1445 static void sdw_release_bus_lock(struct sdw_stream_runtime *stream)
1446 {
1447 	struct sdw_master_runtime *m_rt = NULL;
1448 	struct sdw_bus *bus = NULL;
1449 
1450 	/* Iterate for all Master(s) in Master list */
1451 	list_for_each_entry_reverse(m_rt, &stream->master_list, stream_node) {
1452 		bus = m_rt->bus;
1453 		mutex_unlock(&bus->bus_lock);
1454 	}
1455 }
1456 
1457 static int _sdw_prepare_stream(struct sdw_stream_runtime *stream)
1458 {
1459 	struct sdw_master_runtime *m_rt = NULL;
1460 	struct sdw_bus *bus = NULL;
1461 	struct sdw_master_prop *prop = NULL;
1462 	struct sdw_bus_params params;
1463 	int ret;
1464 
1465 	/* Prepare  Master(s) and Slave(s) port(s) associated with stream */
1466 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1467 		bus = m_rt->bus;
1468 		prop = &bus->prop;
1469 		memcpy(&params, &bus->params, sizeof(params));
1470 
1471 		/* TODO: Support Asynchronous mode */
1472 		if ((prop->max_freq % stream->params.rate) != 0) {
1473 			dev_err(bus->dev, "Async mode not supported");
1474 			return -EINVAL;
1475 		}
1476 
1477 		/* Increment cumulative bus bandwidth */
1478 		/* TODO: Update this during Device-Device support */
1479 		bus->params.bandwidth += m_rt->stream->params.rate *
1480 			m_rt->ch_count * m_rt->stream->params.bps;
1481 
1482 		/* Program params */
1483 		ret = sdw_program_params(bus);
1484 		if (ret < 0) {
1485 			dev_err(bus->dev, "Program params failed: %d", ret);
1486 			goto restore_params;
1487 		}
1488 
1489 	}
1490 
1491 	ret = do_bank_switch(stream);
1492 	if (ret < 0) {
1493 		dev_err(bus->dev, "Bank switch failed: %d", ret);
1494 		goto restore_params;
1495 	}
1496 
1497 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1498 		bus = m_rt->bus;
1499 
1500 		/* Prepare port(s) on the new clock configuration */
1501 		ret = sdw_prep_deprep_ports(m_rt, true);
1502 		if (ret < 0) {
1503 			dev_err(bus->dev, "Prepare port(s) failed ret = %d",
1504 					ret);
1505 			return ret;
1506 		}
1507 	}
1508 
1509 	stream->state = SDW_STREAM_PREPARED;
1510 
1511 	return ret;
1512 
1513 restore_params:
1514 	memcpy(&bus->params, &params, sizeof(params));
1515 	return ret;
1516 }
1517 
1518 /**
1519  * sdw_prepare_stream() - Prepare SoundWire stream
1520  *
1521  * @stream: Soundwire stream
1522  *
1523  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1524  */
1525 int sdw_prepare_stream(struct sdw_stream_runtime *stream)
1526 {
1527 	int ret = 0;
1528 
1529 	if (!stream) {
1530 		pr_err("SoundWire: Handle not found for stream");
1531 		return -EINVAL;
1532 	}
1533 
1534 	sdw_acquire_bus_lock(stream);
1535 
1536 	ret = _sdw_prepare_stream(stream);
1537 	if (ret < 0)
1538 		pr_err("Prepare for stream:%s failed: %d", stream->name, ret);
1539 
1540 	sdw_release_bus_lock(stream);
1541 	return ret;
1542 }
1543 EXPORT_SYMBOL(sdw_prepare_stream);
1544 
1545 static int _sdw_enable_stream(struct sdw_stream_runtime *stream)
1546 {
1547 	struct sdw_master_runtime *m_rt = NULL;
1548 	struct sdw_bus *bus = NULL;
1549 	int ret;
1550 
1551 	/* Enable Master(s) and Slave(s) port(s) associated with stream */
1552 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1553 		bus = m_rt->bus;
1554 
1555 		/* Program params */
1556 		ret = sdw_program_params(bus);
1557 		if (ret < 0) {
1558 			dev_err(bus->dev, "Program params failed: %d", ret);
1559 			return ret;
1560 		}
1561 
1562 		/* Enable port(s) */
1563 		ret = sdw_enable_disable_ports(m_rt, true);
1564 		if (ret < 0) {
1565 			dev_err(bus->dev, "Enable port(s) failed ret: %d", ret);
1566 			return ret;
1567 		}
1568 	}
1569 
1570 	ret = do_bank_switch(stream);
1571 	if (ret < 0) {
1572 		dev_err(bus->dev, "Bank switch failed: %d", ret);
1573 		return ret;
1574 	}
1575 
1576 	stream->state = SDW_STREAM_ENABLED;
1577 	return 0;
1578 }
1579 
1580 /**
1581  * sdw_enable_stream() - Enable SoundWire stream
1582  *
1583  * @stream: Soundwire stream
1584  *
1585  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1586  */
1587 int sdw_enable_stream(struct sdw_stream_runtime *stream)
1588 {
1589 	int ret = 0;
1590 
1591 	if (!stream) {
1592 		pr_err("SoundWire: Handle not found for stream");
1593 		return -EINVAL;
1594 	}
1595 
1596 	sdw_acquire_bus_lock(stream);
1597 
1598 	ret = _sdw_enable_stream(stream);
1599 	if (ret < 0)
1600 		pr_err("Enable for stream:%s failed: %d", stream->name, ret);
1601 
1602 	sdw_release_bus_lock(stream);
1603 	return ret;
1604 }
1605 EXPORT_SYMBOL(sdw_enable_stream);
1606 
1607 static int _sdw_disable_stream(struct sdw_stream_runtime *stream)
1608 {
1609 	struct sdw_master_runtime *m_rt = NULL;
1610 	struct sdw_bus *bus = NULL;
1611 	int ret;
1612 
1613 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1614 		bus = m_rt->bus;
1615 		/* Disable port(s) */
1616 		ret = sdw_enable_disable_ports(m_rt, false);
1617 		if (ret < 0) {
1618 			dev_err(bus->dev, "Disable port(s) failed: %d", ret);
1619 			return ret;
1620 		}
1621 	}
1622 	stream->state = SDW_STREAM_DISABLED;
1623 
1624 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1625 		bus = m_rt->bus;
1626 		/* Program params */
1627 		ret = sdw_program_params(bus);
1628 		if (ret < 0) {
1629 			dev_err(bus->dev, "Program params failed: %d", ret);
1630 			return ret;
1631 		}
1632 	}
1633 
1634 	return do_bank_switch(stream);
1635 }
1636 
1637 /**
1638  * sdw_disable_stream() - Disable SoundWire stream
1639  *
1640  * @stream: Soundwire stream
1641  *
1642  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1643  */
1644 int sdw_disable_stream(struct sdw_stream_runtime *stream)
1645 {
1646 	int ret = 0;
1647 
1648 	if (!stream) {
1649 		pr_err("SoundWire: Handle not found for stream");
1650 		return -EINVAL;
1651 	}
1652 
1653 	sdw_acquire_bus_lock(stream);
1654 
1655 	ret = _sdw_disable_stream(stream);
1656 	if (ret < 0)
1657 		pr_err("Disable for stream:%s failed: %d", stream->name, ret);
1658 
1659 	sdw_release_bus_lock(stream);
1660 	return ret;
1661 }
1662 EXPORT_SYMBOL(sdw_disable_stream);
1663 
1664 static int _sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1665 {
1666 	struct sdw_master_runtime *m_rt = NULL;
1667 	struct sdw_bus *bus = NULL;
1668 	int ret = 0;
1669 
1670 	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
1671 		bus = m_rt->bus;
1672 		/* De-prepare port(s) */
1673 		ret = sdw_prep_deprep_ports(m_rt, false);
1674 		if (ret < 0) {
1675 			dev_err(bus->dev, "De-prepare port(s) failed: %d", ret);
1676 			return ret;
1677 		}
1678 
1679 		/* TODO: Update this during Device-Device support */
1680 		bus->params.bandwidth -= m_rt->stream->params.rate *
1681 			m_rt->ch_count * m_rt->stream->params.bps;
1682 
1683 		/* Program params */
1684 		ret = sdw_program_params(bus);
1685 		if (ret < 0) {
1686 			dev_err(bus->dev, "Program params failed: %d", ret);
1687 			return ret;
1688 		}
1689 
1690 	}
1691 
1692 	stream->state = SDW_STREAM_DEPREPARED;
1693 	return do_bank_switch(stream);
1694 }
1695 
1696 /**
1697  * sdw_deprepare_stream() - Deprepare SoundWire stream
1698  *
1699  * @stream: Soundwire stream
1700  *
1701  * Documentation/driver-api/soundwire/stream.rst explains this API in detail
1702  */
1703 int sdw_deprepare_stream(struct sdw_stream_runtime *stream)
1704 {
1705 	int ret = 0;
1706 
1707 	if (!stream) {
1708 		pr_err("SoundWire: Handle not found for stream");
1709 		return -EINVAL;
1710 	}
1711 
1712 	sdw_acquire_bus_lock(stream);
1713 	ret = _sdw_deprepare_stream(stream);
1714 	if (ret < 0)
1715 		pr_err("De-prepare for stream:%d failed: %d", ret, ret);
1716 
1717 	sdw_release_bus_lock(stream);
1718 	return ret;
1719 }
1720 EXPORT_SYMBOL(sdw_deprepare_stream);
1721