xref: /linux/drivers/hsi/controllers/omap_ssi_port.c (revision 889600e21e3be388a6817c2a0dac0411df860751)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* OMAP SSI port driver.
3  *
4  * Copyright (C) 2010 Nokia Corporation. All rights reserved.
5  * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
6  *
7  * Contact: Carlos Chinea <carlos.chinea@nokia.com>
8  */
9 
10 #include <linux/platform_device.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/delay.h>
14 
15 #include <linux/gpio/consumer.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/debugfs.h>
18 
19 #include "omap_ssi_regs.h"
20 #include "omap_ssi.h"
21 
hsi_dummy_msg(struct hsi_msg * msg __maybe_unused)22 static inline int hsi_dummy_msg(struct hsi_msg *msg __maybe_unused)
23 {
24 	return 0;
25 }
26 
hsi_dummy_cl(struct hsi_client * cl __maybe_unused)27 static inline int hsi_dummy_cl(struct hsi_client *cl __maybe_unused)
28 {
29 	return 0;
30 }
31 
ssi_wakein(struct hsi_port * port)32 static inline unsigned int ssi_wakein(struct hsi_port *port)
33 {
34 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
35 	return gpiod_get_value(omap_port->wake_gpio);
36 }
37 
38 #ifdef CONFIG_DEBUG_FS
ssi_debug_remove_port(struct hsi_port * port)39 static void ssi_debug_remove_port(struct hsi_port *port)
40 {
41 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
42 
43 	debugfs_remove_recursive(omap_port->dir);
44 }
45 
ssi_port_regs_show(struct seq_file * m,void * p __maybe_unused)46 static int ssi_port_regs_show(struct seq_file *m, void *p __maybe_unused)
47 {
48 	struct hsi_port *port = m->private;
49 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
50 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
51 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
52 	void __iomem	*base = omap_ssi->sys;
53 	unsigned int ch;
54 
55 	pm_runtime_get_sync(omap_port->pdev);
56 	if (omap_port->wake_irq > 0)
57 		seq_printf(m, "CAWAKE\t\t: %d\n", ssi_wakein(port));
58 	seq_printf(m, "WAKE\t\t: 0x%08x\n",
59 				readl(base + SSI_WAKE_REG(port->num)));
60 	seq_printf(m, "MPU_ENABLE_IRQ%d\t: 0x%08x\n", 0,
61 			readl(base + SSI_MPU_ENABLE_REG(port->num, 0)));
62 	seq_printf(m, "MPU_STATUS_IRQ%d\t: 0x%08x\n", 0,
63 			readl(base + SSI_MPU_STATUS_REG(port->num, 0)));
64 	/* SST */
65 	base = omap_port->sst_base;
66 	seq_puts(m, "\nSST\n===\n");
67 	seq_printf(m, "ID SST\t\t: 0x%08x\n",
68 				readl(base + SSI_SST_ID_REG));
69 	seq_printf(m, "MODE\t\t: 0x%08x\n",
70 				readl(base + SSI_SST_MODE_REG));
71 	seq_printf(m, "FRAMESIZE\t: 0x%08x\n",
72 				readl(base + SSI_SST_FRAMESIZE_REG));
73 	seq_printf(m, "DIVISOR\t\t: 0x%08x\n",
74 				readl(base + SSI_SST_DIVISOR_REG));
75 	seq_printf(m, "CHANNELS\t: 0x%08x\n",
76 				readl(base + SSI_SST_CHANNELS_REG));
77 	seq_printf(m, "ARBMODE\t\t: 0x%08x\n",
78 				readl(base + SSI_SST_ARBMODE_REG));
79 	seq_printf(m, "TXSTATE\t\t: 0x%08x\n",
80 				readl(base + SSI_SST_TXSTATE_REG));
81 	seq_printf(m, "BUFSTATE\t: 0x%08x\n",
82 				readl(base + SSI_SST_BUFSTATE_REG));
83 	seq_printf(m, "BREAK\t\t: 0x%08x\n",
84 				readl(base + SSI_SST_BREAK_REG));
85 	for (ch = 0; ch < omap_port->channels; ch++) {
86 		seq_printf(m, "BUFFER_CH%d\t: 0x%08x\n", ch,
87 				readl(base + SSI_SST_BUFFER_CH_REG(ch)));
88 	}
89 	/* SSR */
90 	base = omap_port->ssr_base;
91 	seq_puts(m, "\nSSR\n===\n");
92 	seq_printf(m, "ID SSR\t\t: 0x%08x\n",
93 				readl(base + SSI_SSR_ID_REG));
94 	seq_printf(m, "MODE\t\t: 0x%08x\n",
95 				readl(base + SSI_SSR_MODE_REG));
96 	seq_printf(m, "FRAMESIZE\t: 0x%08x\n",
97 				readl(base + SSI_SSR_FRAMESIZE_REG));
98 	seq_printf(m, "CHANNELS\t: 0x%08x\n",
99 				readl(base + SSI_SSR_CHANNELS_REG));
100 	seq_printf(m, "TIMEOUT\t\t: 0x%08x\n",
101 				readl(base + SSI_SSR_TIMEOUT_REG));
102 	seq_printf(m, "RXSTATE\t\t: 0x%08x\n",
103 				readl(base + SSI_SSR_RXSTATE_REG));
104 	seq_printf(m, "BUFSTATE\t: 0x%08x\n",
105 				readl(base + SSI_SSR_BUFSTATE_REG));
106 	seq_printf(m, "BREAK\t\t: 0x%08x\n",
107 				readl(base + SSI_SSR_BREAK_REG));
108 	seq_printf(m, "ERROR\t\t: 0x%08x\n",
109 				readl(base + SSI_SSR_ERROR_REG));
110 	seq_printf(m, "ERRORACK\t: 0x%08x\n",
111 				readl(base + SSI_SSR_ERRORACK_REG));
112 	for (ch = 0; ch < omap_port->channels; ch++) {
113 		seq_printf(m, "BUFFER_CH%d\t: 0x%08x\n", ch,
114 				readl(base + SSI_SSR_BUFFER_CH_REG(ch)));
115 	}
116 	pm_runtime_put_autosuspend(omap_port->pdev);
117 
118 	return 0;
119 }
120 
121 DEFINE_SHOW_ATTRIBUTE(ssi_port_regs);
122 
ssi_div_get(void * data,u64 * val)123 static int ssi_div_get(void *data, u64 *val)
124 {
125 	struct hsi_port *port = data;
126 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
127 
128 	pm_runtime_get_sync(omap_port->pdev);
129 	*val = readl(omap_port->sst_base + SSI_SST_DIVISOR_REG);
130 	pm_runtime_put_autosuspend(omap_port->pdev);
131 
132 	return 0;
133 }
134 
ssi_div_set(void * data,u64 val)135 static int ssi_div_set(void *data, u64 val)
136 {
137 	struct hsi_port *port = data;
138 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
139 
140 	if (val > 127)
141 		return -EINVAL;
142 
143 	pm_runtime_get_sync(omap_port->pdev);
144 	writel(val, omap_port->sst_base + SSI_SST_DIVISOR_REG);
145 	omap_port->sst.divisor = val;
146 	pm_runtime_put_autosuspend(omap_port->pdev);
147 
148 	return 0;
149 }
150 
151 DEFINE_DEBUGFS_ATTRIBUTE(ssi_sst_div_fops, ssi_div_get, ssi_div_set, "%llu\n");
152 
ssi_debug_add_port(struct omap_ssi_port * omap_port,struct dentry * dir)153 static void ssi_debug_add_port(struct omap_ssi_port *omap_port,
154 				     struct dentry *dir)
155 {
156 	struct hsi_port *port = to_hsi_port(omap_port->dev);
157 
158 	dir = debugfs_create_dir(dev_name(omap_port->dev), dir);
159 	omap_port->dir = dir;
160 	debugfs_create_file("regs", S_IRUGO, dir, port, &ssi_port_regs_fops);
161 	dir = debugfs_create_dir("sst", dir);
162 	debugfs_create_file_unsafe("divisor", 0644, dir, port,
163 				   &ssi_sst_div_fops);
164 }
165 #endif
166 
ssi_process_errqueue(struct work_struct * work)167 static void ssi_process_errqueue(struct work_struct *work)
168 {
169 	struct omap_ssi_port *omap_port;
170 	struct list_head *head, *tmp;
171 	struct hsi_msg *msg;
172 
173 	omap_port = container_of(work, struct omap_ssi_port, errqueue_work.work);
174 
175 	list_for_each_safe(head, tmp, &omap_port->errqueue) {
176 		msg = list_entry(head, struct hsi_msg, link);
177 		msg->complete(msg);
178 		list_del(head);
179 	}
180 }
181 
ssi_claim_lch(struct hsi_msg * msg)182 static int ssi_claim_lch(struct hsi_msg *msg)
183 {
184 
185 	struct hsi_port *port = hsi_get_port(msg->cl);
186 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
187 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
188 	int lch;
189 
190 	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++)
191 		if (!omap_ssi->gdd_trn[lch].msg) {
192 			omap_ssi->gdd_trn[lch].msg = msg;
193 			omap_ssi->gdd_trn[lch].sg = msg->sgt.sgl;
194 			return lch;
195 		}
196 
197 	return -EBUSY;
198 }
199 
ssi_start_dma(struct hsi_msg * msg,int lch)200 static int ssi_start_dma(struct hsi_msg *msg, int lch)
201 {
202 	struct hsi_port *port = hsi_get_port(msg->cl);
203 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
204 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
205 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
206 	void __iomem *gdd = omap_ssi->gdd;
207 	int err;
208 	u16 csdp;
209 	u16 ccr;
210 	u32 s_addr;
211 	u32 d_addr;
212 	u32 tmp;
213 
214 	/* Hold clocks during the transfer */
215 	pm_runtime_get(omap_port->pdev);
216 
217 	if (!pm_runtime_active(omap_port->pdev)) {
218 		dev_warn(&port->device, "ssi_start_dma called without runtime PM!\n");
219 		pm_runtime_put_autosuspend(omap_port->pdev);
220 		return -EREMOTEIO;
221 	}
222 
223 	if (msg->ttype == HSI_MSG_READ) {
224 		err = dma_map_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents,
225 							DMA_FROM_DEVICE);
226 		if (!err) {
227 			dev_dbg(&ssi->device, "DMA map SG failed !\n");
228 			pm_runtime_put_autosuspend(omap_port->pdev);
229 			return -EIO;
230 		}
231 		csdp = SSI_DST_BURST_4x32_BIT | SSI_DST_MEMORY_PORT |
232 			SSI_SRC_SINGLE_ACCESS0 | SSI_SRC_PERIPHERAL_PORT |
233 			SSI_DATA_TYPE_S32;
234 		ccr = msg->channel + 0x10 + (port->num * 8); /* Sync */
235 		ccr |= SSI_DST_AMODE_POSTINC | SSI_SRC_AMODE_CONST |
236 			SSI_CCR_ENABLE;
237 		s_addr = omap_port->ssr_dma +
238 					SSI_SSR_BUFFER_CH_REG(msg->channel);
239 		d_addr = sg_dma_address(msg->sgt.sgl);
240 	} else {
241 		err = dma_map_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents,
242 							DMA_TO_DEVICE);
243 		if (!err) {
244 			dev_dbg(&ssi->device, "DMA map SG failed !\n");
245 			pm_runtime_put_autosuspend(omap_port->pdev);
246 			return -EIO;
247 		}
248 		csdp = SSI_SRC_BURST_4x32_BIT | SSI_SRC_MEMORY_PORT |
249 			SSI_DST_SINGLE_ACCESS0 | SSI_DST_PERIPHERAL_PORT |
250 			SSI_DATA_TYPE_S32;
251 		ccr = (msg->channel + 1 + (port->num * 8)) & 0xf; /* Sync */
252 		ccr |= SSI_SRC_AMODE_POSTINC | SSI_DST_AMODE_CONST |
253 			SSI_CCR_ENABLE;
254 		s_addr = sg_dma_address(msg->sgt.sgl);
255 		d_addr = omap_port->sst_dma +
256 					SSI_SST_BUFFER_CH_REG(msg->channel);
257 	}
258 	dev_dbg(&ssi->device, "lch %d cdsp %08x ccr %04x s_addr %08x d_addr %08x\n",
259 		lch, csdp, ccr, s_addr, d_addr);
260 
261 	writew_relaxed(csdp, gdd + SSI_GDD_CSDP_REG(lch));
262 	writew_relaxed(SSI_BLOCK_IE | SSI_TOUT_IE, gdd + SSI_GDD_CICR_REG(lch));
263 	writel_relaxed(d_addr, gdd + SSI_GDD_CDSA_REG(lch));
264 	writel_relaxed(s_addr, gdd + SSI_GDD_CSSA_REG(lch));
265 	writew_relaxed(SSI_BYTES_TO_FRAMES(msg->sgt.sgl->length),
266 						gdd + SSI_GDD_CEN_REG(lch));
267 
268 	spin_lock_bh(&omap_ssi->lock);
269 	tmp = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
270 	tmp |= SSI_GDD_LCH(lch);
271 	writel_relaxed(tmp, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
272 	spin_unlock_bh(&omap_ssi->lock);
273 	writew(ccr, gdd + SSI_GDD_CCR_REG(lch));
274 	msg->status = HSI_STATUS_PROCEEDING;
275 
276 	return 0;
277 }
278 
ssi_start_pio(struct hsi_msg * msg)279 static int ssi_start_pio(struct hsi_msg *msg)
280 {
281 	struct hsi_port *port = hsi_get_port(msg->cl);
282 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
283 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
284 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
285 	u32 val;
286 
287 	pm_runtime_get(omap_port->pdev);
288 
289 	if (!pm_runtime_active(omap_port->pdev)) {
290 		dev_warn(&port->device, "ssi_start_pio called without runtime PM!\n");
291 		pm_runtime_put_autosuspend(omap_port->pdev);
292 		return -EREMOTEIO;
293 	}
294 
295 	if (msg->ttype == HSI_MSG_WRITE) {
296 		val = SSI_DATAACCEPT(msg->channel);
297 		/* Hold clocks for pio writes */
298 		pm_runtime_get(omap_port->pdev);
299 	} else {
300 		val = SSI_DATAAVAILABLE(msg->channel) | SSI_ERROROCCURED;
301 	}
302 	dev_dbg(&port->device, "Single %s transfer\n",
303 						msg->ttype ? "write" : "read");
304 	val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
305 	writel(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
306 	pm_runtime_put_autosuspend(omap_port->pdev);
307 	msg->actual_len = 0;
308 	msg->status = HSI_STATUS_PROCEEDING;
309 
310 	return 0;
311 }
312 
ssi_start_transfer(struct list_head * queue)313 static int ssi_start_transfer(struct list_head *queue)
314 {
315 	struct hsi_msg *msg;
316 	int lch = -1;
317 
318 	if (list_empty(queue))
319 		return 0;
320 	msg = list_first_entry(queue, struct hsi_msg, link);
321 	if (msg->status != HSI_STATUS_QUEUED)
322 		return 0;
323 	if ((msg->sgt.nents) && (msg->sgt.sgl->length > sizeof(u32)))
324 		lch = ssi_claim_lch(msg);
325 	if (lch >= 0)
326 		return ssi_start_dma(msg, lch);
327 	else
328 		return ssi_start_pio(msg);
329 }
330 
ssi_async_break(struct hsi_msg * msg)331 static int ssi_async_break(struct hsi_msg *msg)
332 {
333 	struct hsi_port *port = hsi_get_port(msg->cl);
334 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
335 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
336 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
337 	int err = 0;
338 	u32 tmp;
339 
340 	pm_runtime_get_sync(omap_port->pdev);
341 	if (msg->ttype == HSI_MSG_WRITE) {
342 		if (omap_port->sst.mode != SSI_MODE_FRAME) {
343 			err = -EINVAL;
344 			goto out;
345 		}
346 		writel(1, omap_port->sst_base + SSI_SST_BREAK_REG);
347 		msg->status = HSI_STATUS_COMPLETED;
348 		msg->complete(msg);
349 	} else {
350 		if (omap_port->ssr.mode != SSI_MODE_FRAME) {
351 			err = -EINVAL;
352 			goto out;
353 		}
354 		spin_lock_bh(&omap_port->lock);
355 		tmp = readl(omap_ssi->sys +
356 					SSI_MPU_ENABLE_REG(port->num, 0));
357 		writel(tmp | SSI_BREAKDETECTED,
358 			omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
359 		msg->status = HSI_STATUS_PROCEEDING;
360 		list_add_tail(&msg->link, &omap_port->brkqueue);
361 		spin_unlock_bh(&omap_port->lock);
362 	}
363 out:
364 	pm_runtime_put_autosuspend(omap_port->pdev);
365 
366 	return err;
367 }
368 
ssi_async(struct hsi_msg * msg)369 static int ssi_async(struct hsi_msg *msg)
370 {
371 	struct hsi_port *port = hsi_get_port(msg->cl);
372 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
373 	struct list_head *queue;
374 	int err = 0;
375 
376 	BUG_ON(!msg);
377 
378 	if (msg->sgt.nents > 1)
379 		return -ENOSYS; /* TODO: Add sg support */
380 
381 	if (msg->break_frame)
382 		return ssi_async_break(msg);
383 
384 	if (msg->ttype) {
385 		BUG_ON(msg->channel >= omap_port->sst.channels);
386 		queue = &omap_port->txqueue[msg->channel];
387 	} else {
388 		BUG_ON(msg->channel >= omap_port->ssr.channels);
389 		queue = &omap_port->rxqueue[msg->channel];
390 	}
391 	msg->status = HSI_STATUS_QUEUED;
392 
393 	pm_runtime_get_sync(omap_port->pdev);
394 	spin_lock_bh(&omap_port->lock);
395 	list_add_tail(&msg->link, queue);
396 	err = ssi_start_transfer(queue);
397 	if (err < 0) {
398 		list_del(&msg->link);
399 		msg->status = HSI_STATUS_ERROR;
400 	}
401 	spin_unlock_bh(&omap_port->lock);
402 	pm_runtime_put_autosuspend(omap_port->pdev);
403 	dev_dbg(&port->device, "msg status %d ttype %d ch %d\n",
404 				msg->status, msg->ttype, msg->channel);
405 
406 	return err;
407 }
408 
ssi_calculate_div(struct hsi_controller * ssi)409 static u32 ssi_calculate_div(struct hsi_controller *ssi)
410 {
411 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
412 	u32 tx_fckrate = (u32) omap_ssi->fck_rate;
413 
414 	/* / 2 : SSI TX clock is always half of the SSI functional clock */
415 	tx_fckrate >>= 1;
416 	/* Round down when tx_fckrate % omap_ssi->max_speed == 0 */
417 	tx_fckrate--;
418 	dev_dbg(&ssi->device, "TX div %d for fck_rate %lu Khz speed %d Kb/s\n",
419 		tx_fckrate / omap_ssi->max_speed, omap_ssi->fck_rate,
420 		omap_ssi->max_speed);
421 
422 	return tx_fckrate / omap_ssi->max_speed;
423 }
424 
ssi_flush_queue(struct list_head * queue,struct hsi_client * cl)425 static void ssi_flush_queue(struct list_head *queue, struct hsi_client *cl)
426 {
427 	struct list_head *node, *tmp;
428 	struct hsi_msg *msg;
429 
430 	list_for_each_safe(node, tmp, queue) {
431 		msg = list_entry(node, struct hsi_msg, link);
432 		if ((cl) && (cl != msg->cl))
433 			continue;
434 		list_del(node);
435 		pr_debug("flush queue: ch %d, msg %p len %d type %d ctxt %p\n",
436 			msg->channel, msg, msg->sgt.sgl->length,
437 					msg->ttype, msg->context);
438 		if (msg->destructor)
439 			msg->destructor(msg);
440 		else
441 			hsi_free_msg(msg);
442 	}
443 }
444 
ssi_setup(struct hsi_client * cl)445 static int ssi_setup(struct hsi_client *cl)
446 {
447 	struct hsi_port *port = to_hsi_port(cl->device.parent);
448 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
449 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
450 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
451 	void __iomem *sst = omap_port->sst_base;
452 	void __iomem *ssr = omap_port->ssr_base;
453 	u32 div;
454 	int err = 0;
455 
456 	pm_runtime_get_sync(omap_port->pdev);
457 	spin_lock_bh(&omap_port->lock);
458 	if (cl->tx_cfg.speed)
459 		omap_ssi->max_speed = cl->tx_cfg.speed;
460 	div = ssi_calculate_div(ssi);
461 	if (div > SSI_MAX_DIVISOR) {
462 		dev_err(&cl->device, "Invalid TX speed %d Mb/s (div %d)\n",
463 						cl->tx_cfg.speed, div);
464 		err = -EINVAL;
465 		goto out;
466 	}
467 	/* Set TX/RX module to sleep to stop TX/RX during cfg update */
468 	writel_relaxed(SSI_MODE_SLEEP, sst + SSI_SST_MODE_REG);
469 	writel_relaxed(SSI_MODE_SLEEP, ssr + SSI_SSR_MODE_REG);
470 	/* Flush posted write */
471 	readl(ssr + SSI_SSR_MODE_REG);
472 	/* TX */
473 	writel_relaxed(31, sst + SSI_SST_FRAMESIZE_REG);
474 	writel_relaxed(div, sst + SSI_SST_DIVISOR_REG);
475 	writel_relaxed(cl->tx_cfg.num_hw_channels, sst + SSI_SST_CHANNELS_REG);
476 	writel_relaxed(cl->tx_cfg.arb_mode, sst + SSI_SST_ARBMODE_REG);
477 	writel_relaxed(cl->tx_cfg.mode, sst + SSI_SST_MODE_REG);
478 	/* RX */
479 	writel_relaxed(31, ssr + SSI_SSR_FRAMESIZE_REG);
480 	writel_relaxed(cl->rx_cfg.num_hw_channels, ssr + SSI_SSR_CHANNELS_REG);
481 	writel_relaxed(0, ssr + SSI_SSR_TIMEOUT_REG);
482 	/* Cleanup the break queue if we leave FRAME mode */
483 	if ((omap_port->ssr.mode == SSI_MODE_FRAME) &&
484 		(cl->rx_cfg.mode != SSI_MODE_FRAME))
485 		ssi_flush_queue(&omap_port->brkqueue, cl);
486 	writel_relaxed(cl->rx_cfg.mode, ssr + SSI_SSR_MODE_REG);
487 	omap_port->channels = max(cl->rx_cfg.num_hw_channels,
488 				  cl->tx_cfg.num_hw_channels);
489 	/* Shadow registering for OFF mode */
490 	/* SST */
491 	omap_port->sst.divisor = div;
492 	omap_port->sst.frame_size = 31;
493 	omap_port->sst.channels = cl->tx_cfg.num_hw_channels;
494 	omap_port->sst.arb_mode = cl->tx_cfg.arb_mode;
495 	omap_port->sst.mode = cl->tx_cfg.mode;
496 	/* SSR */
497 	omap_port->ssr.frame_size = 31;
498 	omap_port->ssr.timeout = 0;
499 	omap_port->ssr.channels = cl->rx_cfg.num_hw_channels;
500 	omap_port->ssr.mode = cl->rx_cfg.mode;
501 out:
502 	spin_unlock_bh(&omap_port->lock);
503 	pm_runtime_put_autosuspend(omap_port->pdev);
504 
505 	return err;
506 }
507 
ssi_flush(struct hsi_client * cl)508 static int ssi_flush(struct hsi_client *cl)
509 {
510 	struct hsi_port *port = hsi_get_port(cl);
511 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
512 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
513 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
514 	struct hsi_msg *msg;
515 	void __iomem *sst = omap_port->sst_base;
516 	void __iomem *ssr = omap_port->ssr_base;
517 	unsigned int i;
518 	u32 err;
519 
520 	pm_runtime_get_sync(omap_port->pdev);
521 	spin_lock_bh(&omap_port->lock);
522 
523 	/* stop all ssi communication */
524 	pinctrl_pm_select_idle_state(omap_port->pdev);
525 	udelay(1); /* wait for racing frames */
526 
527 	/* Stop all DMA transfers */
528 	for (i = 0; i < SSI_MAX_GDD_LCH; i++) {
529 		msg = omap_ssi->gdd_trn[i].msg;
530 		if (!msg || (port != hsi_get_port(msg->cl)))
531 			continue;
532 		writew_relaxed(0, omap_ssi->gdd + SSI_GDD_CCR_REG(i));
533 		if (msg->ttype == HSI_MSG_READ)
534 			pm_runtime_put_autosuspend(omap_port->pdev);
535 		omap_ssi->gdd_trn[i].msg = NULL;
536 	}
537 	/* Flush all SST buffers */
538 	writel_relaxed(0, sst + SSI_SST_BUFSTATE_REG);
539 	writel_relaxed(0, sst + SSI_SST_TXSTATE_REG);
540 	/* Flush all SSR buffers */
541 	writel_relaxed(0, ssr + SSI_SSR_RXSTATE_REG);
542 	writel_relaxed(0, ssr + SSI_SSR_BUFSTATE_REG);
543 	/* Flush all errors */
544 	err = readl(ssr + SSI_SSR_ERROR_REG);
545 	writel_relaxed(err, ssr + SSI_SSR_ERRORACK_REG);
546 	/* Flush break */
547 	writel_relaxed(0, ssr + SSI_SSR_BREAK_REG);
548 	/* Clear interrupts */
549 	writel_relaxed(0, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
550 	writel_relaxed(0xffffff00,
551 			omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
552 	writel_relaxed(0, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
553 	writel(0xff, omap_ssi->sys + SSI_GDD_MPU_IRQ_STATUS_REG);
554 	/* Dequeue all pending requests */
555 	for (i = 0; i < omap_port->channels; i++) {
556 		/* Release write clocks */
557 		if (!list_empty(&omap_port->txqueue[i]))
558 			pm_runtime_put_autosuspend(omap_port->pdev);
559 		ssi_flush_queue(&omap_port->txqueue[i], NULL);
560 		ssi_flush_queue(&omap_port->rxqueue[i], NULL);
561 	}
562 	ssi_flush_queue(&omap_port->brkqueue, NULL);
563 
564 	/* Resume SSI communication */
565 	pinctrl_pm_select_default_state(omap_port->pdev);
566 
567 	spin_unlock_bh(&omap_port->lock);
568 	pm_runtime_put_autosuspend(omap_port->pdev);
569 
570 	return 0;
571 }
572 
start_tx_work(struct work_struct * work)573 static void start_tx_work(struct work_struct *work)
574 {
575 	struct omap_ssi_port *omap_port =
576 				container_of(work, struct omap_ssi_port, work);
577 	struct hsi_port *port = to_hsi_port(omap_port->dev);
578 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
579 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
580 
581 	pm_runtime_get_sync(omap_port->pdev); /* Grab clocks */
582 	writel(SSI_WAKE(0), omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
583 }
584 
ssi_start_tx(struct hsi_client * cl)585 static int ssi_start_tx(struct hsi_client *cl)
586 {
587 	struct hsi_port *port = hsi_get_port(cl);
588 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
589 
590 	dev_dbg(&port->device, "Wake out high %d\n", omap_port->wk_refcount);
591 
592 	spin_lock_bh(&omap_port->wk_lock);
593 	if (omap_port->wk_refcount++) {
594 		spin_unlock_bh(&omap_port->wk_lock);
595 		return 0;
596 	}
597 	spin_unlock_bh(&omap_port->wk_lock);
598 
599 	schedule_work(&omap_port->work);
600 
601 	return 0;
602 }
603 
ssi_stop_tx(struct hsi_client * cl)604 static int ssi_stop_tx(struct hsi_client *cl)
605 {
606 	struct hsi_port *port = hsi_get_port(cl);
607 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
608 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
609 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
610 
611 	dev_dbg(&port->device, "Wake out low %d\n", omap_port->wk_refcount);
612 
613 	spin_lock_bh(&omap_port->wk_lock);
614 	BUG_ON(!omap_port->wk_refcount);
615 	if (--omap_port->wk_refcount) {
616 		spin_unlock_bh(&omap_port->wk_lock);
617 		return 0;
618 	}
619 	writel(SSI_WAKE(0), omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
620 	spin_unlock_bh(&omap_port->wk_lock);
621 
622 	pm_runtime_put_autosuspend(omap_port->pdev); /* Release clocks */
623 
624 
625 	return 0;
626 }
627 
ssi_transfer(struct omap_ssi_port * omap_port,struct list_head * queue)628 static void ssi_transfer(struct omap_ssi_port *omap_port,
629 							struct list_head *queue)
630 {
631 	struct hsi_msg *msg;
632 	int err = -1;
633 
634 	pm_runtime_get(omap_port->pdev);
635 	spin_lock_bh(&omap_port->lock);
636 	while (err < 0) {
637 		err = ssi_start_transfer(queue);
638 		if (err < 0) {
639 			msg = list_first_entry(queue, struct hsi_msg, link);
640 			msg->status = HSI_STATUS_ERROR;
641 			msg->actual_len = 0;
642 			list_del(&msg->link);
643 			spin_unlock_bh(&omap_port->lock);
644 			msg->complete(msg);
645 			spin_lock_bh(&omap_port->lock);
646 		}
647 	}
648 	spin_unlock_bh(&omap_port->lock);
649 	pm_runtime_put_autosuspend(omap_port->pdev);
650 }
651 
ssi_cleanup_queues(struct hsi_client * cl)652 static void ssi_cleanup_queues(struct hsi_client *cl)
653 {
654 	struct hsi_port *port = hsi_get_port(cl);
655 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
656 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
657 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
658 	struct hsi_msg *msg;
659 	unsigned int i;
660 	u32 rxbufstate = 0;
661 	u32 txbufstate = 0;
662 	u32 status = SSI_ERROROCCURED;
663 	u32 tmp;
664 
665 	ssi_flush_queue(&omap_port->brkqueue, cl);
666 	if (list_empty(&omap_port->brkqueue))
667 		status |= SSI_BREAKDETECTED;
668 
669 	for (i = 0; i < omap_port->channels; i++) {
670 		if (list_empty(&omap_port->txqueue[i]))
671 			continue;
672 		msg = list_first_entry(&omap_port->txqueue[i], struct hsi_msg,
673 									link);
674 		if ((msg->cl == cl) && (msg->status == HSI_STATUS_PROCEEDING)) {
675 			txbufstate |= (1 << i);
676 			status |= SSI_DATAACCEPT(i);
677 			/* Release the clocks writes, also GDD ones */
678 			pm_runtime_put_autosuspend(omap_port->pdev);
679 		}
680 		ssi_flush_queue(&omap_port->txqueue[i], cl);
681 	}
682 	for (i = 0; i < omap_port->channels; i++) {
683 		if (list_empty(&omap_port->rxqueue[i]))
684 			continue;
685 		msg = list_first_entry(&omap_port->rxqueue[i], struct hsi_msg,
686 									link);
687 		if ((msg->cl == cl) && (msg->status == HSI_STATUS_PROCEEDING)) {
688 			rxbufstate |= (1 << i);
689 			status |= SSI_DATAAVAILABLE(i);
690 		}
691 		ssi_flush_queue(&omap_port->rxqueue[i], cl);
692 		/* Check if we keep the error detection interrupt armed */
693 		if (!list_empty(&omap_port->rxqueue[i]))
694 			status &= ~SSI_ERROROCCURED;
695 	}
696 	/* Cleanup write buffers */
697 	tmp = readl(omap_port->sst_base + SSI_SST_BUFSTATE_REG);
698 	tmp &= ~txbufstate;
699 	writel_relaxed(tmp, omap_port->sst_base + SSI_SST_BUFSTATE_REG);
700 	/* Cleanup read buffers */
701 	tmp = readl(omap_port->ssr_base + SSI_SSR_BUFSTATE_REG);
702 	tmp &= ~rxbufstate;
703 	writel_relaxed(tmp, omap_port->ssr_base + SSI_SSR_BUFSTATE_REG);
704 	/* Disarm and ack pending interrupts */
705 	tmp = readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
706 	tmp &= ~status;
707 	writel_relaxed(tmp, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
708 	writel_relaxed(status, omap_ssi->sys +
709 		SSI_MPU_STATUS_REG(port->num, 0));
710 }
711 
ssi_cleanup_gdd(struct hsi_controller * ssi,struct hsi_client * cl)712 static void ssi_cleanup_gdd(struct hsi_controller *ssi, struct hsi_client *cl)
713 {
714 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
715 	struct hsi_port *port = hsi_get_port(cl);
716 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
717 	struct hsi_msg *msg;
718 	unsigned int i;
719 	u32 val = 0;
720 	u32 tmp;
721 
722 	for (i = 0; i < SSI_MAX_GDD_LCH; i++) {
723 		msg = omap_ssi->gdd_trn[i].msg;
724 		if ((!msg) || (msg->cl != cl))
725 			continue;
726 		writew_relaxed(0, omap_ssi->gdd + SSI_GDD_CCR_REG(i));
727 		val |= (1 << i);
728 		/*
729 		 * Clock references for write will be handled in
730 		 * ssi_cleanup_queues
731 		 */
732 		if (msg->ttype == HSI_MSG_READ) {
733 			pm_runtime_put_autosuspend(omap_port->pdev);
734 		}
735 		omap_ssi->gdd_trn[i].msg = NULL;
736 	}
737 	tmp = readl_relaxed(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
738 	tmp &= ~val;
739 	writel_relaxed(tmp, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
740 	writel(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_STATUS_REG);
741 }
742 
ssi_set_port_mode(struct omap_ssi_port * omap_port,u32 mode)743 static int ssi_set_port_mode(struct omap_ssi_port *omap_port, u32 mode)
744 {
745 	writel(mode, omap_port->sst_base + SSI_SST_MODE_REG);
746 	writel(mode, omap_port->ssr_base + SSI_SSR_MODE_REG);
747 	/* OCP barrier */
748 	mode = readl(omap_port->ssr_base + SSI_SSR_MODE_REG);
749 
750 	return 0;
751 }
752 
ssi_release(struct hsi_client * cl)753 static int ssi_release(struct hsi_client *cl)
754 {
755 	struct hsi_port *port = hsi_get_port(cl);
756 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
757 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
758 
759 	pm_runtime_get_sync(omap_port->pdev);
760 	spin_lock_bh(&omap_port->lock);
761 	/* Stop all the pending DMA requests for that client */
762 	ssi_cleanup_gdd(ssi, cl);
763 	/* Now cleanup all the queues */
764 	ssi_cleanup_queues(cl);
765 	/* If it is the last client of the port, do extra checks and cleanup */
766 	if (port->claimed <= 1) {
767 		/*
768 		 * Drop the clock reference for the incoming wake line
769 		 * if it is still kept high by the other side.
770 		 */
771 		if (test_and_clear_bit(SSI_WAKE_EN, &omap_port->flags))
772 			pm_runtime_put_sync(omap_port->pdev);
773 		pm_runtime_get(omap_port->pdev);
774 		/* Stop any SSI TX/RX without a client */
775 		ssi_set_port_mode(omap_port, SSI_MODE_SLEEP);
776 		omap_port->sst.mode = SSI_MODE_SLEEP;
777 		omap_port->ssr.mode = SSI_MODE_SLEEP;
778 		pm_runtime_put(omap_port->pdev);
779 		WARN_ON(omap_port->wk_refcount != 0);
780 	}
781 	spin_unlock_bh(&omap_port->lock);
782 	pm_runtime_put_sync(omap_port->pdev);
783 
784 	return 0;
785 }
786 
787 
788 
ssi_error(struct hsi_port * port)789 static void ssi_error(struct hsi_port *port)
790 {
791 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
792 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
793 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
794 	struct hsi_msg *msg;
795 	unsigned int i;
796 	u32 err;
797 	u32 val;
798 	u32 tmp;
799 
800 	/* ACK error */
801 	err = readl(omap_port->ssr_base + SSI_SSR_ERROR_REG);
802 	dev_err(&port->device, "SSI error: 0x%02x\n", err);
803 	if (!err) {
804 		dev_dbg(&port->device, "spurious SSI error ignored!\n");
805 		return;
806 	}
807 	spin_lock(&omap_ssi->lock);
808 	/* Cancel all GDD read transfers */
809 	for (i = 0, val = 0; i < SSI_MAX_GDD_LCH; i++) {
810 		msg = omap_ssi->gdd_trn[i].msg;
811 		if ((msg) && (msg->ttype == HSI_MSG_READ)) {
812 			writew_relaxed(0, omap_ssi->gdd + SSI_GDD_CCR_REG(i));
813 			val |= (1 << i);
814 			omap_ssi->gdd_trn[i].msg = NULL;
815 		}
816 	}
817 	tmp = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
818 	tmp &= ~val;
819 	writel_relaxed(tmp, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
820 	spin_unlock(&omap_ssi->lock);
821 	/* Cancel all PIO read transfers */
822 	spin_lock(&omap_port->lock);
823 	tmp = readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
824 	tmp &= 0xfeff00ff; /* Disable error & all dataavailable interrupts */
825 	writel_relaxed(tmp, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
826 	/* ACK error */
827 	writel_relaxed(err, omap_port->ssr_base + SSI_SSR_ERRORACK_REG);
828 	writel_relaxed(SSI_ERROROCCURED,
829 			omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
830 	/* Signal the error all current pending read requests */
831 	for (i = 0; i < omap_port->channels; i++) {
832 		if (list_empty(&omap_port->rxqueue[i]))
833 			continue;
834 		msg = list_first_entry(&omap_port->rxqueue[i], struct hsi_msg,
835 									link);
836 		list_del(&msg->link);
837 		msg->status = HSI_STATUS_ERROR;
838 		spin_unlock(&omap_port->lock);
839 		msg->complete(msg);
840 		/* Now restart queued reads if any */
841 		ssi_transfer(omap_port, &omap_port->rxqueue[i]);
842 		spin_lock(&omap_port->lock);
843 	}
844 	spin_unlock(&omap_port->lock);
845 }
846 
ssi_break_complete(struct hsi_port * port)847 static void ssi_break_complete(struct hsi_port *port)
848 {
849 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
850 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
851 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
852 	struct hsi_msg *msg;
853 	struct hsi_msg *tmp;
854 	u32 val;
855 
856 	dev_dbg(&port->device, "HWBREAK received\n");
857 
858 	spin_lock(&omap_port->lock);
859 	val = readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
860 	val &= ~SSI_BREAKDETECTED;
861 	writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
862 	writel_relaxed(0, omap_port->ssr_base + SSI_SSR_BREAK_REG);
863 	writel(SSI_BREAKDETECTED,
864 			omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
865 	spin_unlock(&omap_port->lock);
866 
867 	list_for_each_entry_safe(msg, tmp, &omap_port->brkqueue, link) {
868 		msg->status = HSI_STATUS_COMPLETED;
869 		spin_lock(&omap_port->lock);
870 		list_del(&msg->link);
871 		spin_unlock(&omap_port->lock);
872 		msg->complete(msg);
873 	}
874 
875 }
876 
ssi_pio_complete(struct hsi_port * port,struct list_head * queue)877 static void ssi_pio_complete(struct hsi_port *port, struct list_head *queue)
878 {
879 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
880 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
881 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
882 	struct hsi_msg *msg;
883 	u32 *buf;
884 	u32 reg;
885 	u32 val;
886 
887 	spin_lock_bh(&omap_port->lock);
888 	msg = list_first_entry(queue, struct hsi_msg, link);
889 	if ((!msg->sgt.nents) || (!msg->sgt.sgl->length)) {
890 		msg->actual_len = 0;
891 		msg->status = HSI_STATUS_PENDING;
892 	}
893 	if (msg->ttype == HSI_MSG_WRITE)
894 		val = SSI_DATAACCEPT(msg->channel);
895 	else
896 		val = SSI_DATAAVAILABLE(msg->channel);
897 	if (msg->status == HSI_STATUS_PROCEEDING) {
898 		buf = sg_virt(msg->sgt.sgl) + msg->actual_len;
899 		if (msg->ttype == HSI_MSG_WRITE)
900 			writel(*buf, omap_port->sst_base +
901 					SSI_SST_BUFFER_CH_REG(msg->channel));
902 		 else
903 			*buf = readl(omap_port->ssr_base +
904 					SSI_SSR_BUFFER_CH_REG(msg->channel));
905 		dev_dbg(&port->device, "ch %d ttype %d 0x%08x\n", msg->channel,
906 							msg->ttype, *buf);
907 		msg->actual_len += sizeof(*buf);
908 		if (msg->actual_len >= msg->sgt.sgl->length)
909 			msg->status = HSI_STATUS_COMPLETED;
910 		/*
911 		 * Wait for the last written frame to be really sent before
912 		 * we call the complete callback
913 		 */
914 		if ((msg->status == HSI_STATUS_PROCEEDING) ||
915 				((msg->status == HSI_STATUS_COMPLETED) &&
916 					(msg->ttype == HSI_MSG_WRITE))) {
917 			writel(val, omap_ssi->sys +
918 					SSI_MPU_STATUS_REG(port->num, 0));
919 			spin_unlock_bh(&omap_port->lock);
920 
921 			return;
922 		}
923 
924 	}
925 	/* Transfer completed at this point */
926 	reg = readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
927 	if (msg->ttype == HSI_MSG_WRITE) {
928 		/* Release clocks for write transfer */
929 		pm_runtime_put_autosuspend(omap_port->pdev);
930 	}
931 	reg &= ~val;
932 	writel_relaxed(reg, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
933 	writel_relaxed(val, omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
934 	list_del(&msg->link);
935 	spin_unlock_bh(&omap_port->lock);
936 	msg->complete(msg);
937 	ssi_transfer(omap_port, queue);
938 }
939 
ssi_pio_thread(int irq,void * ssi_port)940 static irqreturn_t ssi_pio_thread(int irq, void *ssi_port)
941 {
942 	struct hsi_port *port = (struct hsi_port *)ssi_port;
943 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
944 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
945 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
946 	void __iomem *sys = omap_ssi->sys;
947 	unsigned int ch;
948 	u32 status_reg;
949 
950 	pm_runtime_get_sync(omap_port->pdev);
951 
952 	do {
953 		status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
954 		status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
955 
956 		for (ch = 0; ch < omap_port->channels; ch++) {
957 			if (status_reg & SSI_DATAACCEPT(ch))
958 				ssi_pio_complete(port, &omap_port->txqueue[ch]);
959 			if (status_reg & SSI_DATAAVAILABLE(ch))
960 				ssi_pio_complete(port, &omap_port->rxqueue[ch]);
961 		}
962 		if (status_reg & SSI_BREAKDETECTED)
963 			ssi_break_complete(port);
964 		if (status_reg & SSI_ERROROCCURED)
965 			ssi_error(port);
966 
967 		status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
968 		status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
969 
970 		/* TODO: sleep if we retry? */
971 	} while (status_reg);
972 
973 	pm_runtime_put_autosuspend(omap_port->pdev);
974 
975 	return IRQ_HANDLED;
976 }
977 
ssi_wake_thread(int irq __maybe_unused,void * ssi_port)978 static irqreturn_t ssi_wake_thread(int irq __maybe_unused, void *ssi_port)
979 {
980 	struct hsi_port *port = (struct hsi_port *)ssi_port;
981 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
982 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
983 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
984 
985 	if (ssi_wakein(port)) {
986 		/**
987 		 * We can have a quick High-Low-High transition in the line.
988 		 * In such a case if we have long interrupt latencies,
989 		 * we can miss the low event or get twice a high event.
990 		 * This workaround will avoid breaking the clock reference
991 		 * count when such a situation ocurrs.
992 		 */
993 		if (!test_and_set_bit(SSI_WAKE_EN, &omap_port->flags))
994 			pm_runtime_get_sync(omap_port->pdev);
995 		dev_dbg(&ssi->device, "Wake in high\n");
996 		if (omap_port->wktest) { /* FIXME: HACK ! To be removed */
997 			writel(SSI_WAKE(0),
998 				omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
999 		}
1000 		hsi_event(port, HSI_EVENT_START_RX);
1001 	} else {
1002 		dev_dbg(&ssi->device, "Wake in low\n");
1003 		if (omap_port->wktest) { /* FIXME: HACK ! To be removed */
1004 			writel(SSI_WAKE(0),
1005 				omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
1006 		}
1007 		hsi_event(port, HSI_EVENT_STOP_RX);
1008 		if (test_and_clear_bit(SSI_WAKE_EN, &omap_port->flags)) {
1009 			pm_runtime_put_autosuspend(omap_port->pdev);
1010 		}
1011 	}
1012 
1013 	return IRQ_HANDLED;
1014 }
1015 
ssi_port_irq(struct hsi_port * port,struct platform_device * pd)1016 static int ssi_port_irq(struct hsi_port *port, struct platform_device *pd)
1017 {
1018 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
1019 	int err;
1020 
1021 	err = platform_get_irq(pd, 0);
1022 	if (err < 0)
1023 		return err;
1024 	omap_port->irq = err;
1025 	err = devm_request_threaded_irq(&port->device, omap_port->irq, NULL,
1026 				ssi_pio_thread, IRQF_ONESHOT, "SSI PORT", port);
1027 	return err;
1028 }
1029 
ssi_wake_irq(struct hsi_port * port,struct platform_device * pd)1030 static int ssi_wake_irq(struct hsi_port *port, struct platform_device *pd)
1031 {
1032 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
1033 	int cawake_irq;
1034 	int err;
1035 
1036 	if (!omap_port->wake_gpio) {
1037 		omap_port->wake_irq = -1;
1038 		return 0;
1039 	}
1040 
1041 	cawake_irq = gpiod_to_irq(omap_port->wake_gpio);
1042 	omap_port->wake_irq = cawake_irq;
1043 
1044 	err = devm_request_threaded_irq(&port->device, cawake_irq, NULL,
1045 		ssi_wake_thread,
1046 		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
1047 		"SSI cawake", port);
1048 	err = enable_irq_wake(cawake_irq);
1049 	if (err < 0)
1050 		dev_err(&port->device, "Enable wake on the wakeline in irq %d failed %d\n",
1051 			cawake_irq, err);
1052 
1053 	return err;
1054 }
1055 
ssi_queues_init(struct omap_ssi_port * omap_port)1056 static void ssi_queues_init(struct omap_ssi_port *omap_port)
1057 {
1058 	unsigned int ch;
1059 
1060 	for (ch = 0; ch < SSI_MAX_CHANNELS; ch++) {
1061 		INIT_LIST_HEAD(&omap_port->txqueue[ch]);
1062 		INIT_LIST_HEAD(&omap_port->rxqueue[ch]);
1063 	}
1064 	INIT_LIST_HEAD(&omap_port->brkqueue);
1065 }
1066 
ssi_port_get_iomem(struct platform_device * pd,const char * name,void __iomem ** pbase,dma_addr_t * phy)1067 static int ssi_port_get_iomem(struct platform_device *pd,
1068 		const char *name, void __iomem **pbase, dma_addr_t *phy)
1069 {
1070 	struct hsi_port *port = platform_get_drvdata(pd);
1071 	struct resource *mem;
1072 	struct resource *ioarea;
1073 	void __iomem *base;
1074 
1075 	mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
1076 	if (!mem) {
1077 		dev_err(&pd->dev, "IO memory region missing (%s)\n", name);
1078 		return -ENXIO;
1079 	}
1080 	ioarea = devm_request_mem_region(&port->device, mem->start,
1081 					resource_size(mem), dev_name(&pd->dev));
1082 	if (!ioarea) {
1083 		dev_err(&pd->dev, "%s IO memory region request failed\n",
1084 								mem->name);
1085 		return -ENXIO;
1086 	}
1087 	base = devm_ioremap(&port->device, mem->start, resource_size(mem));
1088 	if (!base) {
1089 		dev_err(&pd->dev, "%s IO remap failed\n", mem->name);
1090 		return -ENXIO;
1091 	}
1092 	*pbase = base;
1093 
1094 	if (phy)
1095 		*phy = mem->start;
1096 
1097 	return 0;
1098 }
1099 
ssi_port_probe(struct platform_device * pd)1100 static int ssi_port_probe(struct platform_device *pd)
1101 {
1102 	struct device_node *np = pd->dev.of_node;
1103 	struct hsi_port *port;
1104 	struct omap_ssi_port *omap_port;
1105 	struct hsi_controller *ssi = dev_get_drvdata(pd->dev.parent);
1106 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1107 	struct gpio_desc *cawake_gpio = NULL;
1108 	u32 port_id;
1109 	int err;
1110 
1111 	dev_dbg(&pd->dev, "init ssi port...\n");
1112 
1113 	if (!omap_ssi->port) {
1114 		dev_err(&pd->dev, "ssi controller not initialized!\n");
1115 		err = -ENODEV;
1116 		goto error;
1117 	}
1118 
1119 	/* get id of first uninitialized port in controller */
1120 	for (port_id = 0; port_id < ssi->num_ports && omap_ssi->port[port_id];
1121 		port_id++)
1122 		;
1123 
1124 	if (port_id >= ssi->num_ports) {
1125 		dev_err(&pd->dev, "port id out of range!\n");
1126 		err = -ENODEV;
1127 		goto error;
1128 	}
1129 
1130 	port = ssi->port[port_id];
1131 
1132 	if (!np) {
1133 		dev_err(&pd->dev, "missing device tree data\n");
1134 		err = -EINVAL;
1135 		goto error;
1136 	}
1137 
1138 	cawake_gpio = devm_gpiod_get(&pd->dev, "ti,ssi-cawake", GPIOD_IN);
1139 	if (IS_ERR(cawake_gpio)) {
1140 		err = PTR_ERR(cawake_gpio);
1141 		dev_err(&pd->dev, "couldn't get cawake gpio (err=%d)!\n", err);
1142 		goto error;
1143 	}
1144 
1145 	omap_port = devm_kzalloc(&port->device, sizeof(*omap_port), GFP_KERNEL);
1146 	if (!omap_port) {
1147 		err = -ENOMEM;
1148 		goto error;
1149 	}
1150 	omap_port->wake_gpio = cawake_gpio;
1151 	omap_port->pdev = &pd->dev;
1152 	omap_port->port_id = port_id;
1153 
1154 	INIT_DEFERRABLE_WORK(&omap_port->errqueue_work, ssi_process_errqueue);
1155 	INIT_WORK(&omap_port->work, start_tx_work);
1156 
1157 	/* initialize HSI port */
1158 	port->async	= ssi_async;
1159 	port->setup	= ssi_setup;
1160 	port->flush	= ssi_flush;
1161 	port->start_tx	= ssi_start_tx;
1162 	port->stop_tx	= ssi_stop_tx;
1163 	port->release	= ssi_release;
1164 	hsi_port_set_drvdata(port, omap_port);
1165 	omap_ssi->port[port_id] = omap_port;
1166 
1167 	platform_set_drvdata(pd, port);
1168 
1169 	err = ssi_port_get_iomem(pd, "tx", &omap_port->sst_base,
1170 		&omap_port->sst_dma);
1171 	if (err < 0)
1172 		goto error;
1173 	err = ssi_port_get_iomem(pd, "rx", &omap_port->ssr_base,
1174 		&omap_port->ssr_dma);
1175 	if (err < 0)
1176 		goto error;
1177 
1178 	err = ssi_port_irq(port, pd);
1179 	if (err < 0)
1180 		goto error;
1181 	err = ssi_wake_irq(port, pd);
1182 	if (err < 0)
1183 		goto error;
1184 
1185 	ssi_queues_init(omap_port);
1186 	spin_lock_init(&omap_port->lock);
1187 	spin_lock_init(&omap_port->wk_lock);
1188 	omap_port->dev = &port->device;
1189 
1190 	pm_runtime_use_autosuspend(omap_port->pdev);
1191 	pm_runtime_set_autosuspend_delay(omap_port->pdev, 250);
1192 	pm_runtime_enable(omap_port->pdev);
1193 
1194 #ifdef CONFIG_DEBUG_FS
1195 	ssi_debug_add_port(omap_port, omap_ssi->dir);
1196 #endif
1197 
1198 	hsi_add_clients_from_dt(port, np);
1199 
1200 	dev_info(&pd->dev, "ssi port %u successfully initialized\n", port_id);
1201 
1202 	return 0;
1203 
1204 error:
1205 	return err;
1206 }
1207 
ssi_port_remove(struct platform_device * pd)1208 static void ssi_port_remove(struct platform_device *pd)
1209 {
1210 	struct hsi_port *port = platform_get_drvdata(pd);
1211 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
1212 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
1213 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1214 
1215 #ifdef CONFIG_DEBUG_FS
1216 	ssi_debug_remove_port(port);
1217 #endif
1218 
1219 	cancel_delayed_work_sync(&omap_port->errqueue_work);
1220 
1221 	hsi_port_unregister_clients(port);
1222 
1223 	port->async	= hsi_dummy_msg;
1224 	port->setup	= hsi_dummy_cl;
1225 	port->flush	= hsi_dummy_cl;
1226 	port->start_tx	= hsi_dummy_cl;
1227 	port->stop_tx	= hsi_dummy_cl;
1228 	port->release	= hsi_dummy_cl;
1229 
1230 	omap_ssi->port[omap_port->port_id] = NULL;
1231 	platform_set_drvdata(pd, NULL);
1232 
1233 	pm_runtime_dont_use_autosuspend(&pd->dev);
1234 	pm_runtime_disable(&pd->dev);
1235 }
1236 
ssi_restore_divisor(struct omap_ssi_port * omap_port)1237 static int ssi_restore_divisor(struct omap_ssi_port *omap_port)
1238 {
1239 	writel_relaxed(omap_port->sst.divisor,
1240 				omap_port->sst_base + SSI_SST_DIVISOR_REG);
1241 
1242 	return 0;
1243 }
1244 
omap_ssi_port_update_fclk(struct hsi_controller * ssi,struct omap_ssi_port * omap_port)1245 void omap_ssi_port_update_fclk(struct hsi_controller *ssi,
1246 			       struct omap_ssi_port *omap_port)
1247 {
1248 	/* update divisor */
1249 	u32 div = ssi_calculate_div(ssi);
1250 	omap_port->sst.divisor = div;
1251 	ssi_restore_divisor(omap_port);
1252 }
1253 
1254 #ifdef CONFIG_PM
ssi_save_port_ctx(struct omap_ssi_port * omap_port)1255 static int ssi_save_port_ctx(struct omap_ssi_port *omap_port)
1256 {
1257 	struct hsi_port *port = to_hsi_port(omap_port->dev);
1258 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
1259 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1260 
1261 	omap_port->sys_mpu_enable = readl(omap_ssi->sys +
1262 					SSI_MPU_ENABLE_REG(port->num, 0));
1263 
1264 	return 0;
1265 }
1266 
ssi_restore_port_ctx(struct omap_ssi_port * omap_port)1267 static int ssi_restore_port_ctx(struct omap_ssi_port *omap_port)
1268 {
1269 	struct hsi_port *port = to_hsi_port(omap_port->dev);
1270 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
1271 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1272 	void __iomem	*base;
1273 
1274 	writel_relaxed(omap_port->sys_mpu_enable,
1275 			omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
1276 
1277 	/* SST context */
1278 	base = omap_port->sst_base;
1279 	writel_relaxed(omap_port->sst.frame_size, base + SSI_SST_FRAMESIZE_REG);
1280 	writel_relaxed(omap_port->sst.channels, base + SSI_SST_CHANNELS_REG);
1281 	writel_relaxed(omap_port->sst.arb_mode, base + SSI_SST_ARBMODE_REG);
1282 
1283 	/* SSR context */
1284 	base = omap_port->ssr_base;
1285 	writel_relaxed(omap_port->ssr.frame_size, base + SSI_SSR_FRAMESIZE_REG);
1286 	writel_relaxed(omap_port->ssr.channels, base + SSI_SSR_CHANNELS_REG);
1287 	writel_relaxed(omap_port->ssr.timeout, base + SSI_SSR_TIMEOUT_REG);
1288 
1289 	return 0;
1290 }
1291 
ssi_restore_port_mode(struct omap_ssi_port * omap_port)1292 static int ssi_restore_port_mode(struct omap_ssi_port *omap_port)
1293 {
1294 	writel_relaxed(omap_port->sst.mode,
1295 				omap_port->sst_base + SSI_SST_MODE_REG);
1296 	writel_relaxed(omap_port->ssr.mode,
1297 				omap_port->ssr_base + SSI_SSR_MODE_REG);
1298 	/* OCP barrier */
1299 	readl(omap_port->ssr_base + SSI_SSR_MODE_REG);
1300 
1301 	return 0;
1302 }
1303 
omap_ssi_port_runtime_suspend(struct device * dev)1304 static int omap_ssi_port_runtime_suspend(struct device *dev)
1305 {
1306 	struct hsi_port *port = dev_get_drvdata(dev);
1307 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
1308 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
1309 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1310 
1311 	dev_dbg(dev, "port runtime suspend!\n");
1312 
1313 	ssi_set_port_mode(omap_port, SSI_MODE_SLEEP);
1314 	if (omap_ssi->get_loss)
1315 		omap_port->loss_count =
1316 				omap_ssi->get_loss(ssi->device.parent);
1317 	ssi_save_port_ctx(omap_port);
1318 
1319 	return 0;
1320 }
1321 
omap_ssi_port_runtime_resume(struct device * dev)1322 static int omap_ssi_port_runtime_resume(struct device *dev)
1323 {
1324 	struct hsi_port *port = dev_get_drvdata(dev);
1325 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
1326 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
1327 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
1328 
1329 	dev_dbg(dev, "port runtime resume!\n");
1330 
1331 	if ((omap_ssi->get_loss) && (omap_port->loss_count ==
1332 				omap_ssi->get_loss(ssi->device.parent)))
1333 		goto mode; /* We always need to restore the mode & TX divisor */
1334 
1335 	ssi_restore_port_ctx(omap_port);
1336 
1337 mode:
1338 	ssi_restore_divisor(omap_port);
1339 	ssi_restore_port_mode(omap_port);
1340 
1341 	return 0;
1342 }
1343 
1344 static const struct dev_pm_ops omap_ssi_port_pm_ops = {
1345 	SET_RUNTIME_PM_OPS(omap_ssi_port_runtime_suspend,
1346 		omap_ssi_port_runtime_resume, NULL)
1347 };
1348 
1349 #define DEV_PM_OPS     (&omap_ssi_port_pm_ops)
1350 #else
1351 #define DEV_PM_OPS     NULL
1352 #endif
1353 
1354 
1355 #ifdef CONFIG_OF
1356 static const struct of_device_id omap_ssi_port_of_match[] = {
1357 	{ .compatible = "ti,omap3-ssi-port", },
1358 	{},
1359 };
1360 MODULE_DEVICE_TABLE(of, omap_ssi_port_of_match);
1361 #else
1362 #define omap_ssi_port_of_match NULL
1363 #endif
1364 
1365 struct platform_driver ssi_port_pdriver = {
1366 	.probe = ssi_port_probe,
1367 	.remove = ssi_port_remove,
1368 	.driver	= {
1369 		.name	= "omap_ssi_port",
1370 		.of_match_table = omap_ssi_port_of_match,
1371 		.pm	= DEV_PM_OPS,
1372 	},
1373 };
1374