xref: /openbmc/linux/drivers/usb/renesas_usbhs/mod.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Renesas USB driver
4  *
5  * Copyright (C) 2011 Renesas Solutions Corp.
6  * Copyright (C) 2019 Renesas Electronics Corporation
7  * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
8  */
9 #include <linux/interrupt.h>
10 
11 #include "common.h"
12 #include "mod.h"
13 
14 /*
15  *		autonomy
16  *
17  * these functions are used if platform doesn't have external phy.
18  *  -> there is no "notify_hotplug" callback from platform
19  *  -> call "notify_hotplug" by itself
20  *  -> use own interrupt to connect/disconnect
21  *  -> it mean module clock is always ON
22  *             ~~~~~~~~~~~~~~~~~~~~~~~~~
23  */
24 static int usbhsm_autonomy_get_vbus(struct platform_device *pdev)
25 {
26 	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
27 
28 	return  VBSTS & usbhs_read(priv, INTSTS0);
29 }
30 
31 static int usbhsm_autonomy_irq_vbus(struct usbhs_priv *priv,
32 				    struct usbhs_irq_state *irq_state)
33 {
34 	struct platform_device *pdev = usbhs_priv_to_pdev(priv);
35 
36 	usbhsc_schedule_notify_hotplug(pdev);
37 
38 	return 0;
39 }
40 
41 void usbhs_mod_autonomy_mode(struct usbhs_priv *priv)
42 {
43 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
44 
45 	info->irq_vbus = usbhsm_autonomy_irq_vbus;
46 	info->get_vbus = usbhsm_autonomy_get_vbus;
47 
48 	usbhs_irq_callback_update(priv, NULL);
49 }
50 
51 void usbhs_mod_non_autonomy_mode(struct usbhs_priv *priv)
52 {
53 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
54 
55 	info->get_vbus = priv->pfunc->get_vbus;
56 }
57 
58 /*
59  *		host / gadget functions
60  *
61  * renesas_usbhs host/gadget can register itself by below functions.
62  * these functions are called when probe
63  *
64  */
65 void usbhs_mod_register(struct usbhs_priv *priv, struct usbhs_mod *mod, int id)
66 {
67 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
68 
69 	info->mod[id]	= mod;
70 	mod->priv	= priv;
71 }
72 
73 struct usbhs_mod *usbhs_mod_get(struct usbhs_priv *priv, int id)
74 {
75 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
76 	struct usbhs_mod *ret = NULL;
77 
78 	switch (id) {
79 	case USBHS_HOST:
80 	case USBHS_GADGET:
81 		ret = info->mod[id];
82 		break;
83 	}
84 
85 	return ret;
86 }
87 
88 int usbhs_mod_is_host(struct usbhs_priv *priv)
89 {
90 	struct usbhs_mod *mod = usbhs_mod_get_current(priv);
91 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
92 
93 	if (!mod)
94 		return -EINVAL;
95 
96 	return info->mod[USBHS_HOST] == mod;
97 }
98 
99 struct usbhs_mod *usbhs_mod_get_current(struct usbhs_priv *priv)
100 {
101 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
102 
103 	return info->curt;
104 }
105 
106 int usbhs_mod_change(struct usbhs_priv *priv, int id)
107 {
108 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
109 	struct usbhs_mod *mod = NULL;
110 	int ret = 0;
111 
112 	/* id < 0 mean no current */
113 	switch (id) {
114 	case USBHS_HOST:
115 	case USBHS_GADGET:
116 		mod = info->mod[id];
117 		break;
118 	default:
119 		ret = -EINVAL;
120 	}
121 	info->curt = mod;
122 
123 	return ret;
124 }
125 
126 static irqreturn_t usbhs_interrupt(int irq, void *data);
127 int usbhs_mod_probe(struct usbhs_priv *priv)
128 {
129 	struct device *dev = usbhs_priv_to_dev(priv);
130 	int ret;
131 
132 	/*
133 	 * install host/gadget driver
134 	 */
135 	ret = usbhs_mod_host_probe(priv);
136 	if (ret < 0)
137 		return ret;
138 
139 	ret = usbhs_mod_gadget_probe(priv);
140 	if (ret < 0)
141 		goto mod_init_host_err;
142 
143 	/* irq settings */
144 	ret = devm_request_irq(dev, priv->irq, usbhs_interrupt,
145 			  priv->irqflags, dev_name(dev), priv);
146 	if (ret) {
147 		dev_err(dev, "irq request err\n");
148 		goto mod_init_gadget_err;
149 	}
150 
151 	return ret;
152 
153 mod_init_gadget_err:
154 	usbhs_mod_gadget_remove(priv);
155 mod_init_host_err:
156 	usbhs_mod_host_remove(priv);
157 
158 	return ret;
159 }
160 
161 void usbhs_mod_remove(struct usbhs_priv *priv)
162 {
163 	usbhs_mod_host_remove(priv);
164 	usbhs_mod_gadget_remove(priv);
165 }
166 
167 /*
168  *		status functions
169  */
170 int usbhs_status_get_device_state(struct usbhs_irq_state *irq_state)
171 {
172 	int state = irq_state->intsts0 & DVSQ_MASK;
173 
174 	switch (state) {
175 	case POWER_STATE:
176 	case DEFAULT_STATE:
177 	case ADDRESS_STATE:
178 	case CONFIGURATION_STATE:
179 		return state;
180 	}
181 
182 	return -EIO;
183 }
184 
185 int usbhs_status_get_ctrl_stage(struct usbhs_irq_state *irq_state)
186 {
187 	/*
188 	 * return value
189 	 *
190 	 * IDLE_SETUP_STAGE
191 	 * READ_DATA_STAGE
192 	 * READ_STATUS_STAGE
193 	 * WRITE_DATA_STAGE
194 	 * WRITE_STATUS_STAGE
195 	 * NODATA_STATUS_STAGE
196 	 * SEQUENCE_ERROR
197 	 */
198 	return (int)irq_state->intsts0 & CTSQ_MASK;
199 }
200 
201 static int usbhs_status_get_each_irq(struct usbhs_priv *priv,
202 				     struct usbhs_irq_state *state)
203 {
204 	struct usbhs_mod *mod = usbhs_mod_get_current(priv);
205 	u16 intenb0, intenb1;
206 	unsigned long flags;
207 
208 	/********************  spin lock ********************/
209 	usbhs_lock(priv, flags);
210 	state->intsts0 = usbhs_read(priv, INTSTS0);
211 	intenb0 = usbhs_read(priv, INTENB0);
212 
213 	if (usbhs_mod_is_host(priv)) {
214 		state->intsts1 = usbhs_read(priv, INTSTS1);
215 		intenb1 = usbhs_read(priv, INTENB1);
216 	} else {
217 		state->intsts1 = intenb1 = 0;
218 	}
219 
220 	/* mask */
221 	if (mod) {
222 		state->brdysts = usbhs_read(priv, BRDYSTS);
223 		state->nrdysts = usbhs_read(priv, NRDYSTS);
224 		state->bempsts = usbhs_read(priv, BEMPSTS);
225 
226 		state->bempsts &= mod->irq_bempsts;
227 		state->brdysts &= mod->irq_brdysts;
228 	}
229 	usbhs_unlock(priv, flags);
230 	/********************  spin unlock ******************/
231 
232 	/*
233 	 * Check whether the irq enable registers and the irq status are set
234 	 * when IRQF_SHARED is set.
235 	 */
236 	if (priv->irqflags & IRQF_SHARED) {
237 		if (!(intenb0 & state->intsts0) &&
238 		    !(intenb1 & state->intsts1) &&
239 		    !(state->bempsts) &&
240 		    !(state->brdysts))
241 			return -EIO;
242 	}
243 
244 	return 0;
245 }
246 
247 /*
248  *		interrupt
249  */
250 #define INTSTS0_MAGIC 0xF800 /* acknowledge magical interrupt sources */
251 #define INTSTS1_MAGIC 0xA870 /* acknowledge magical interrupt sources */
252 static irqreturn_t usbhs_interrupt(int irq, void *data)
253 {
254 	struct usbhs_priv *priv = data;
255 	struct usbhs_irq_state irq_state;
256 
257 	if (usbhs_status_get_each_irq(priv, &irq_state) < 0)
258 		return IRQ_NONE;
259 
260 	/*
261 	 * clear interrupt
262 	 *
263 	 * The hardware is _very_ picky to clear interrupt bit.
264 	 * Especially INTSTS0_MAGIC, INTSTS1_MAGIC value.
265 	 *
266 	 * see
267 	 *	"Operation"
268 	 *	 - "Control Transfer (DCP)"
269 	 *	   - Function :: VALID bit should 0
270 	 */
271 	usbhs_write(priv, INTSTS0, ~irq_state.intsts0 & INTSTS0_MAGIC);
272 	if (usbhs_mod_is_host(priv))
273 		usbhs_write(priv, INTSTS1, ~irq_state.intsts1 & INTSTS1_MAGIC);
274 
275 	/*
276 	 * The driver should not clear the xxxSTS after the line of
277 	 * "call irq callback functions" because each "if" statement is
278 	 * possible to call the callback function for avoiding any side effects.
279 	 */
280 	if (irq_state.intsts0 & BRDY)
281 		usbhs_write(priv, BRDYSTS, ~irq_state.brdysts);
282 	usbhs_write(priv, NRDYSTS, ~irq_state.nrdysts);
283 	if (irq_state.intsts0 & BEMP)
284 		usbhs_write(priv, BEMPSTS, ~irq_state.bempsts);
285 
286 	/*
287 	 * call irq callback functions
288 	 * see also
289 	 *	usbhs_irq_setting_update
290 	 */
291 
292 	/* INTSTS0 */
293 	if (irq_state.intsts0 & VBINT)
294 		usbhs_mod_info_call(priv, irq_vbus, priv, &irq_state);
295 
296 	if (irq_state.intsts0 & DVST)
297 		usbhs_mod_call(priv, irq_dev_state, priv, &irq_state);
298 
299 	if (irq_state.intsts0 & CTRT)
300 		usbhs_mod_call(priv, irq_ctrl_stage, priv, &irq_state);
301 
302 	if (irq_state.intsts0 & BEMP)
303 		usbhs_mod_call(priv, irq_empty, priv, &irq_state);
304 
305 	if (irq_state.intsts0 & BRDY)
306 		usbhs_mod_call(priv, irq_ready, priv, &irq_state);
307 
308 	if (usbhs_mod_is_host(priv)) {
309 		/* INTSTS1 */
310 		if (irq_state.intsts1 & ATTCH)
311 			usbhs_mod_call(priv, irq_attch, priv, &irq_state);
312 
313 		if (irq_state.intsts1 & DTCH)
314 			usbhs_mod_call(priv, irq_dtch, priv, &irq_state);
315 
316 		if (irq_state.intsts1 & SIGN)
317 			usbhs_mod_call(priv, irq_sign, priv, &irq_state);
318 
319 		if (irq_state.intsts1 & SACK)
320 			usbhs_mod_call(priv, irq_sack, priv, &irq_state);
321 	}
322 	return IRQ_HANDLED;
323 }
324 
325 void usbhs_irq_callback_update(struct usbhs_priv *priv, struct usbhs_mod *mod)
326 {
327 	u16 intenb0 = 0;
328 	u16 intenb1 = 0;
329 	struct usbhs_mod_info *info = usbhs_priv_to_modinfo(priv);
330 
331 	/*
332 	 * BEMPENB/BRDYENB are picky.
333 	 * below method is required
334 	 *
335 	 *  - clear  INTSTS0
336 	 *  - update BEMPENB/BRDYENB
337 	 *  - update INTSTS0
338 	 */
339 	usbhs_write(priv, INTENB0, 0);
340 	if (usbhs_mod_is_host(priv))
341 		usbhs_write(priv, INTENB1, 0);
342 
343 	usbhs_write(priv, BEMPENB, 0);
344 	usbhs_write(priv, BRDYENB, 0);
345 
346 	/*
347 	 * see also
348 	 *	usbhs_interrupt
349 	 */
350 
351 	/*
352 	 * it don't enable DVSE (intenb0) here
353 	 * but "mod->irq_dev_state" will be called.
354 	 */
355 	if (info->irq_vbus)
356 		intenb0 |= VBSE;
357 
358 	if (mod) {
359 		/*
360 		 * INTSTS0
361 		 */
362 		if (mod->irq_ctrl_stage)
363 			intenb0 |= CTRE;
364 
365 		if (mod->irq_empty && mod->irq_bempsts) {
366 			usbhs_write(priv, BEMPENB, mod->irq_bempsts);
367 			intenb0 |= BEMPE;
368 		}
369 
370 		if (mod->irq_ready && mod->irq_brdysts) {
371 			usbhs_write(priv, BRDYENB, mod->irq_brdysts);
372 			intenb0 |= BRDYE;
373 		}
374 
375 		if (usbhs_mod_is_host(priv)) {
376 			/*
377 			 * INTSTS1
378 			 */
379 			if (mod->irq_attch)
380 				intenb1 |= ATTCHE;
381 
382 			if (mod->irq_dtch)
383 				intenb1 |= DTCHE;
384 
385 			if (mod->irq_sign)
386 				intenb1 |= SIGNE;
387 
388 			if (mod->irq_sack)
389 				intenb1 |= SACKE;
390 		}
391 	}
392 
393 	if (intenb0)
394 		usbhs_write(priv, INTENB0, intenb0);
395 
396 	if (usbhs_mod_is_host(priv) && intenb1)
397 		usbhs_write(priv, INTENB1, intenb1);
398 }
399