gpio-feature.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Apple Onboard Audio feature call GPIO control
  4 *
  5 * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
  6 *
  7 * This file contains the GPIO control routines for
  8 * direct (through feature calls) access to the GPIO
  9 * registers.
 10 */
 11
 12#include <linux/of_irq.h>
 13#include <linux/interrupt.h>
 14#include <asm/pmac_feature.h>
 15#include "../aoa.h"
 16
 17/* TODO: these are lots of global variables
 18 * that aren't used on most machines...
 19 * Move them into a dynamically allocated
 20 * structure and use that.
 21 */
 22
 23/* these are the GPIO numbers (register addresses as offsets into
 24 * the GPIO space) */
 25static int headphone_mute_gpio;
 26static int master_mute_gpio;
 27static int amp_mute_gpio;
 28static int lineout_mute_gpio;
 29static int hw_reset_gpio;
 30static int lineout_detect_gpio;
 31static int headphone_detect_gpio;
 32static int linein_detect_gpio;
 33
 34/* see the SWITCH_GPIO macro */
 35static int headphone_mute_gpio_activestate;
 36static int master_mute_gpio_activestate;
 37static int amp_mute_gpio_activestate;
 38static int lineout_mute_gpio_activestate;
 39static int hw_reset_gpio_activestate;
 40static int lineout_detect_gpio_activestate;
 41static int headphone_detect_gpio_activestate;
 42static int linein_detect_gpio_activestate;
 43
 44/* node pointers that we save when getting the GPIO number
 45 * to get the interrupt later */
 46static struct device_node *lineout_detect_node;
 47static struct device_node *linein_detect_node;
 48static struct device_node *headphone_detect_node;
 49
 50static int lineout_detect_irq;
 51static int linein_detect_irq;
 52static int headphone_detect_irq;
 53
 54static struct device_node *get_gpio(char *name,
 55				    char *altname,
 56				    int *gpioptr,
 57				    int *gpioactiveptr)
 58{
 59	struct device_node *np, *gpio;
 60	const u32 *reg;
 61	const char *audio_gpio;
 62
 63	*gpioptr = -1;
 64
 65	/* check if we can get it the easy way ... */
 66	np = of_find_node_by_name(NULL, name);
 67	if (!np) {
 68		/* some machines have only gpioX/extint-gpioX nodes,
 69		 * and an audio-gpio property saying what it is ...
 70		 * So what we have to do is enumerate all children
 71		 * of the gpio node and check them all. */
 72		gpio = of_find_node_by_name(NULL, "gpio");
 73		if (!gpio)
 74			return NULL;
 75		while ((np = of_get_next_child(gpio, np))) {
 76			audio_gpio = of_get_property(np, "audio-gpio", NULL);
 77			if (!audio_gpio)
 78				continue;
 79			if (strcmp(audio_gpio, name) == 0)
 80				break;
 81			if (altname && (strcmp(audio_gpio, altname) == 0))
 82				break;
 83		}
 84		of_node_put(gpio);
 85		/* still not found, assume not there */
 86		if (!np)
 87			return NULL;
 88	}
 89
 90	reg = of_get_property(np, "reg", NULL);
 91	if (!reg) {
 92		of_node_put(np);
 93		return NULL;
 94	}
 95
 96	*gpioptr = *reg;
 97
 98	/* this is a hack, usually the GPIOs 'reg' property
 99	 * should have the offset based from the GPIO space
100	 * which is at 0x50, but apparently not always... */
101	if (*gpioptr < 0x50)
102		*gpioptr += 0x50;
103
104	reg = of_get_property(np, "audio-gpio-active-state", NULL);
105	if (!reg)
106		/* Apple seems to default to 1, but
107		 * that doesn't seem right at least on most
108		 * machines. So until proven that the opposite
109		 * is necessary, we default to 0
110		 * (which, incidentally, snd-powermac also does...) */
111		*gpioactiveptr = 0;
112	else
113		*gpioactiveptr = *reg;
114
115	return np;
116}
117
118static void get_irq(struct device_node * np, int *irqptr)
119{
120	if (np)
121		*irqptr = irq_of_parse_and_map(np, 0);
122	else
123		*irqptr = 0;
124}
125
126/* 0x4 is outenable, 0x1 is out, thus 4 or 5 */
127#define SWITCH_GPIO(name, v, on)				\
128	(((v)&~1) | ((on)?					\
129			(name##_gpio_activestate==0?4:5):	\
130			(name##_gpio_activestate==0?5:4)))
131
132#define FTR_GPIO(name, bit)					\
133static void ftr_gpio_set_##name(struct gpio_runtime *rt, int on)\
134{								\
135	int v;							\
136								\
137	if (unlikely(!rt)) return;				\
138								\
139	if (name##_mute_gpio < 0)				\
140		return;						\
141								\
142	v = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL,		\
143			      name##_mute_gpio,			\
144			      0);				\
145								\
146	/* muted = !on... */					\
147	v = SWITCH_GPIO(name##_mute, v, !on);			\
148								\
149	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL,		\
150			  name##_mute_gpio, v);			\
151								\
152	rt->implementation_private &= ~(1<<bit);		\
153	rt->implementation_private |= (!!on << bit);		\
154}								\
155static int ftr_gpio_get_##name(struct gpio_runtime *rt)		\
156{								\
157	if (unlikely(!rt)) return 0;				\
158	return (rt->implementation_private>>bit)&1;		\
159}
160
161FTR_GPIO(headphone, 0);
162FTR_GPIO(amp, 1);
163FTR_GPIO(lineout, 2);
164FTR_GPIO(master, 3);
165
166static void ftr_gpio_set_hw_reset(struct gpio_runtime *rt, int on)
167{
168	int v;
169
170	if (unlikely(!rt)) return;
171	if (hw_reset_gpio < 0)
172		return;
173
174	v = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL,
175			      hw_reset_gpio, 0);
176	v = SWITCH_GPIO(hw_reset, v, on);
177	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL,
178			  hw_reset_gpio, v);
179}
180
181static struct gpio_methods methods;
182
183static void ftr_gpio_all_amps_off(struct gpio_runtime *rt)
184{
185	int saved;
186
187	if (unlikely(!rt)) return;
188	saved = rt->implementation_private;
189	ftr_gpio_set_headphone(rt, 0);
190	ftr_gpio_set_amp(rt, 0);
191	ftr_gpio_set_lineout(rt, 0);
192	if (methods.set_master)
193		ftr_gpio_set_master(rt, 0);
194	rt->implementation_private = saved;
195}
196
197static void ftr_gpio_all_amps_restore(struct gpio_runtime *rt)
198{
199	int s;
200
201	if (unlikely(!rt)) return;
202	s = rt->implementation_private;
203	ftr_gpio_set_headphone(rt, (s>>0)&1);
204	ftr_gpio_set_amp(rt, (s>>1)&1);
205	ftr_gpio_set_lineout(rt, (s>>2)&1);
206	if (methods.set_master)
207		ftr_gpio_set_master(rt, (s>>3)&1);
208}
209
210static void ftr_handle_notify(struct work_struct *work)
211{
212	struct gpio_notification *notif =
213		container_of(work, struct gpio_notification, work.work);
214
215	guard(mutex)(&notif->mutex);
216	if (notif->notify)
217		notif->notify(notif->data);
218}
219
220static void gpio_enable_dual_edge(int gpio)
221{
222	int v;
223
224	if (gpio == -1)
225		return;
226	v = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, gpio, 0);
227	v |= 0x80; /* enable dual edge */
228	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, gpio, v);
229}
230
231static void ftr_gpio_init(struct gpio_runtime *rt)
232{
233	get_gpio("headphone-mute", NULL,
234		 &headphone_mute_gpio,
235		 &headphone_mute_gpio_activestate);
236	get_gpio("amp-mute", NULL,
237		 &amp_mute_gpio,
238		 &amp_mute_gpio_activestate);
239	get_gpio("lineout-mute", NULL,
240		 &lineout_mute_gpio,
241		 &lineout_mute_gpio_activestate);
242	get_gpio("hw-reset", "audio-hw-reset",
243		 &hw_reset_gpio,
244		 &hw_reset_gpio_activestate);
245	if (get_gpio("master-mute", NULL,
246		     &master_mute_gpio,
247		     &master_mute_gpio_activestate)) {
248		methods.set_master = ftr_gpio_set_master;
249		methods.get_master = ftr_gpio_get_master;
250	}
251
252	headphone_detect_node = get_gpio("headphone-detect", NULL,
253					 &headphone_detect_gpio,
254					 &headphone_detect_gpio_activestate);
255	/* go Apple, and thanks for giving these different names
256	 * across the board... */
257	lineout_detect_node = get_gpio("lineout-detect", "line-output-detect",
258				       &lineout_detect_gpio,
259				       &lineout_detect_gpio_activestate);
260	linein_detect_node = get_gpio("linein-detect", "line-input-detect",
261				      &linein_detect_gpio,
262				      &linein_detect_gpio_activestate);
263
264	gpio_enable_dual_edge(headphone_detect_gpio);
265	gpio_enable_dual_edge(lineout_detect_gpio);
266	gpio_enable_dual_edge(linein_detect_gpio);
267
268	get_irq(headphone_detect_node, &headphone_detect_irq);
269	get_irq(lineout_detect_node, &lineout_detect_irq);
270	get_irq(linein_detect_node, &linein_detect_irq);
271
272	ftr_gpio_all_amps_off(rt);
273	rt->implementation_private = 0;
274	INIT_DELAYED_WORK(&rt->headphone_notify.work, ftr_handle_notify);
275	INIT_DELAYED_WORK(&rt->line_in_notify.work, ftr_handle_notify);
276	INIT_DELAYED_WORK(&rt->line_out_notify.work, ftr_handle_notify);
277	mutex_init(&rt->headphone_notify.mutex);
278	mutex_init(&rt->line_in_notify.mutex);
279	mutex_init(&rt->line_out_notify.mutex);
280}
281
282static void ftr_gpio_exit(struct gpio_runtime *rt)
283{
284	ftr_gpio_all_amps_off(rt);
285	rt->implementation_private = 0;
286	if (rt->headphone_notify.notify)
287		free_irq(headphone_detect_irq, &rt->headphone_notify);
288	if (rt->line_in_notify.gpio_private)
289		free_irq(linein_detect_irq, &rt->line_in_notify);
290	if (rt->line_out_notify.gpio_private)
291		free_irq(lineout_detect_irq, &rt->line_out_notify);
292	cancel_delayed_work_sync(&rt->headphone_notify.work);
293	cancel_delayed_work_sync(&rt->line_in_notify.work);
294	cancel_delayed_work_sync(&rt->line_out_notify.work);
295	mutex_destroy(&rt->headphone_notify.mutex);
296	mutex_destroy(&rt->line_in_notify.mutex);
297	mutex_destroy(&rt->line_out_notify.mutex);
298}
299
300static irqreturn_t ftr_handle_notify_irq(int xx, void *data)
301{
302	struct gpio_notification *notif = data;
303
304	schedule_delayed_work(&notif->work, 0);
305
306	return IRQ_HANDLED;
307}
308
309static int ftr_set_notify(struct gpio_runtime *rt,
310			  enum notify_type type,
311			  notify_func_t notify,
312			  void *data)
313{
314	struct gpio_notification *notif;
315	notify_func_t old;
316	int irq;
317	char *name;
318	int err = -EBUSY;
319
320	switch (type) {
321	case AOA_NOTIFY_HEADPHONE:
322		notif = &rt->headphone_notify;
323		name = "headphone-detect";
324		irq = headphone_detect_irq;
325		break;
326	case AOA_NOTIFY_LINE_IN:
327		notif = &rt->line_in_notify;
328		name = "linein-detect";
329		irq = linein_detect_irq;
330		break;
331	case AOA_NOTIFY_LINE_OUT:
332		notif = &rt->line_out_notify;
333		name = "lineout-detect";
334		irq = lineout_detect_irq;
335		break;
336	default:
337		return -EINVAL;
338	}
339
340	if (!irq)
341		return -ENODEV;
342
343	guard(mutex)(&notif->mutex);
344
345	old = notif->notify;
346
347	if (!old && !notify)
348		return 0;
349
350	if (old && notify) {
351		if (old == notify && notif->data == data)
352			err = 0;
353		return err;
354	}
355
356	if (old && !notify)
357		free_irq(irq, notif);
358
359	if (!old && notify) {
360		err = request_irq(irq, ftr_handle_notify_irq, 0, name, notif);
361		if (err)
362			return err;
363	}
364
365	notif->notify = notify;
366	notif->data = data;
367
368	return 0;
369}
370
371static int ftr_get_detect(struct gpio_runtime *rt,
372			  enum notify_type type)
373{
374	int gpio, ret, active;
375
376	switch (type) {
377	case AOA_NOTIFY_HEADPHONE:
378		gpio = headphone_detect_gpio;
379		active = headphone_detect_gpio_activestate;
380		break;
381	case AOA_NOTIFY_LINE_IN:
382		gpio = linein_detect_gpio;
383		active = linein_detect_gpio_activestate;
384		break;
385	case AOA_NOTIFY_LINE_OUT:
386		gpio = lineout_detect_gpio;
387		active = lineout_detect_gpio_activestate;
388		break;
389	default:
390		return -EINVAL;
391	}
392
393	if (gpio == -1)
394		return -ENODEV;
395
396	ret = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, gpio, 0);
397	if (ret < 0)
398		return ret;
399	return ((ret >> 1) & 1) == active;
400}
401
402static struct gpio_methods methods = {
403	.init			= ftr_gpio_init,
404	.exit			= ftr_gpio_exit,
405	.all_amps_off		= ftr_gpio_all_amps_off,
406	.all_amps_restore	= ftr_gpio_all_amps_restore,
407	.set_headphone		= ftr_gpio_set_headphone,
408	.set_speakers		= ftr_gpio_set_amp,
409	.set_lineout		= ftr_gpio_set_lineout,
410	.set_hw_reset		= ftr_gpio_set_hw_reset,
411	.get_headphone		= ftr_gpio_get_headphone,
412	.get_speakers		= ftr_gpio_get_amp,
413	.get_lineout		= ftr_gpio_get_lineout,
414	.set_notify		= ftr_set_notify,
415	.get_detect		= ftr_get_detect,
416};
417
418struct gpio_methods *ftr_gpio_methods = &methods;
419EXPORT_SYMBOL_GPL(ftr_gpio_methods);