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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores.
  4 *
  5 * 2013 (c) Aeroflex Gaisler AB
  6 *
  7 * This driver supports the GRGPIO GPIO core available in the GRLIB VHDL
  8 * IP core library.
  9 *
 10 * Full documentation of the GRGPIO core can be found here:
 11 * http://www.gaisler.com/products/grlib/grip.pdf
 12 *
 13 * See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for
 14 * information on open firmware properties.
 15 *
 16 * Contributors: Andreas Larsson <andreas@gaisler.com>
 17 */
 18
 19#include <linux/bitops.h>
 20#include <linux/err.h>
 21#include <linux/gpio/driver.h>
 22#include <linux/init.h>
 23#include <linux/interrupt.h>
 24#include <linux/io.h>
 25#include <linux/irq.h>
 26#include <linux/irqdomain.h>
 27#include <linux/kernel.h>
 28#include <linux/module.h>
 
 
 
 29#include <linux/of.h>
 30#include <linux/platform_device.h>
 
 31#include <linux/slab.h>
 32#include <linux/spinlock.h>
 
 
 
 
 33
 34#define GRGPIO_MAX_NGPIO 32
 35
 36#define GRGPIO_DATA		0x00
 37#define GRGPIO_OUTPUT		0x04
 38#define GRGPIO_DIR		0x08
 39#define GRGPIO_IMASK		0x0c
 40#define GRGPIO_IPOL		0x10
 41#define GRGPIO_IEDGE		0x14
 42#define GRGPIO_BYPASS		0x18
 43#define GRGPIO_IMAP_BASE	0x20
 44
 45/* Structure for an irq of the core - called an underlying irq */
 46struct grgpio_uirq {
 47	u8 refcnt; /* Reference counter to manage requesting/freeing of uirq */
 48	u8 uirq; /* Underlying irq of the gpio driver */
 49};
 50
 51/*
 52 * Structure for an irq of a gpio line handed out by this driver. The index is
 53 * used to map to the corresponding underlying irq.
 54 */
 55struct grgpio_lirq {
 56	s8 index; /* Index into struct grgpio_priv's uirqs, or -1 */
 57	u8 irq; /* irq for the gpio line */
 58};
 59
 60struct grgpio_priv {
 61	struct gpio_chip gc;
 62	void __iomem *regs;
 63	struct device *dev;
 64
 65	u32 imask; /* irq mask shadow register */
 66
 67	/*
 68	 * The grgpio core can have multiple "underlying" irqs. The gpio lines
 69	 * can be mapped to any one or none of these underlying irqs
 70	 * independently of each other. This driver sets up an irq domain and
 71	 * hands out separate irqs to each gpio line
 72	 */
 73	struct irq_domain *domain;
 74
 75	/*
 76	 * This array contains information on each underlying irq, each
 77	 * irq of the grgpio core itself.
 78	 */
 79	struct grgpio_uirq uirqs[GRGPIO_MAX_NGPIO];
 80
 81	/*
 82	 * This array contains information for each gpio line on the irqs
 83	 * obtains from this driver. An index value of -1 for a certain gpio
 84	 * line indicates that the line has no irq. Otherwise the index connects
 85	 * the irq to the underlying irq by pointing into the uirqs array.
 86	 */
 87	struct grgpio_lirq lirqs[GRGPIO_MAX_NGPIO];
 88};
 89
 90static void grgpio_set_imask(struct grgpio_priv *priv, unsigned int offset,
 91			     int val)
 92{
 93	struct gpio_chip *gc = &priv->gc;
 94
 95	if (val)
 96		priv->imask |= BIT(offset);
 97	else
 98		priv->imask &= ~BIT(offset);
 99	gc->write_reg(priv->regs + GRGPIO_IMASK, priv->imask);
100}
101
102static int grgpio_to_irq(struct gpio_chip *gc, unsigned offset)
103{
104	struct grgpio_priv *priv = gpiochip_get_data(gc);
105
106	if (offset >= gc->ngpio)
107		return -ENXIO;
108
109	if (priv->lirqs[offset].index < 0)
110		return -ENXIO;
111
112	return irq_create_mapping(priv->domain, offset);
113}
114
115/* -------------------- IRQ chip functions -------------------- */
116
117static int grgpio_irq_set_type(struct irq_data *d, unsigned int type)
118{
119	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
120	unsigned long flags;
121	u32 mask = BIT(d->hwirq);
122	u32 ipol;
123	u32 iedge;
124	u32 pol;
125	u32 edge;
126
127	switch (type) {
128	case IRQ_TYPE_LEVEL_LOW:
129		pol = 0;
130		edge = 0;
131		break;
132	case IRQ_TYPE_LEVEL_HIGH:
133		pol = mask;
134		edge = 0;
135		break;
136	case IRQ_TYPE_EDGE_FALLING:
137		pol = 0;
138		edge = mask;
139		break;
140	case IRQ_TYPE_EDGE_RISING:
141		pol = mask;
142		edge = mask;
143		break;
144	default:
145		return -EINVAL;
146	}
147
148	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
149
150	ipol = priv->gc.read_reg(priv->regs + GRGPIO_IPOL) & ~mask;
151	iedge = priv->gc.read_reg(priv->regs + GRGPIO_IEDGE) & ~mask;
152
153	priv->gc.write_reg(priv->regs + GRGPIO_IPOL, ipol | pol);
154	priv->gc.write_reg(priv->regs + GRGPIO_IEDGE, iedge | edge);
155
156	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
157
158	return 0;
159}
160
161static void grgpio_irq_mask(struct irq_data *d)
162{
163	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
164	int offset = d->hwirq;
165	unsigned long flags;
166
167	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
168
169	grgpio_set_imask(priv, offset, 0);
170
171	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
172}
173
174static void grgpio_irq_unmask(struct irq_data *d)
175{
176	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
177	int offset = d->hwirq;
178	unsigned long flags;
179
180	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
181
182	grgpio_set_imask(priv, offset, 1);
183
184	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
185}
186
187static struct irq_chip grgpio_irq_chip = {
188	.name			= "grgpio",
189	.irq_mask		= grgpio_irq_mask,
190	.irq_unmask		= grgpio_irq_unmask,
191	.irq_set_type		= grgpio_irq_set_type,
192};
193
194static irqreturn_t grgpio_irq_handler(int irq, void *dev)
195{
196	struct grgpio_priv *priv = dev;
197	int ngpio = priv->gc.ngpio;
198	unsigned long flags;
199	int i;
200	int match = 0;
201
202	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
203
204	/*
205	 * For each gpio line, call its interrupt handler if it its underlying
206	 * irq matches the current irq that is handled.
207	 */
208	for (i = 0; i < ngpio; i++) {
209		struct grgpio_lirq *lirq = &priv->lirqs[i];
210
211		if (priv->imask & BIT(i) && lirq->index >= 0 &&
212		    priv->uirqs[lirq->index].uirq == irq) {
213			generic_handle_irq(lirq->irq);
214			match = 1;
215		}
216	}
217
218	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
219
220	if (!match)
221		dev_warn(priv->dev, "No gpio line matched irq %d\n", irq);
222
223	return IRQ_HANDLED;
224}
225
226/*
227 * This function will be called as a consequence of the call to
228 * irq_create_mapping in grgpio_to_irq
229 */
230static int grgpio_irq_map(struct irq_domain *d, unsigned int irq,
231			  irq_hw_number_t hwirq)
232{
233	struct grgpio_priv *priv = d->host_data;
234	struct grgpio_lirq *lirq;
235	struct grgpio_uirq *uirq;
236	unsigned long flags;
237	int offset = hwirq;
238	int ret = 0;
239
240	if (!priv)
241		return -EINVAL;
242
243	lirq = &priv->lirqs[offset];
244	if (lirq->index < 0)
245		return -EINVAL;
246
247	dev_dbg(priv->dev, "Mapping irq %d for gpio line %d\n",
248		irq, offset);
249
250	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
251
252	/* Request underlying irq if not already requested */
253	lirq->irq = irq;
254	uirq = &priv->uirqs[lirq->index];
255	if (uirq->refcnt == 0) {
256		raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
257		ret = request_irq(uirq->uirq, grgpio_irq_handler, 0,
258				  dev_name(priv->dev), priv);
259		if (ret) {
260			dev_err(priv->dev,
261				"Could not request underlying irq %d\n",
262				uirq->uirq);
 
 
 
263			return ret;
264		}
265		raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
266	}
267	uirq->refcnt++;
268
269	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
270
271	/* Setup irq  */
272	irq_set_chip_data(irq, priv);
273	irq_set_chip_and_handler(irq, &grgpio_irq_chip,
274				 handle_simple_irq);
275	irq_set_noprobe(irq);
276
277	return ret;
278}
279
280static void grgpio_irq_unmap(struct irq_domain *d, unsigned int irq)
281{
282	struct grgpio_priv *priv = d->host_data;
283	int index;
284	struct grgpio_lirq *lirq;
285	struct grgpio_uirq *uirq;
286	unsigned long flags;
287	int ngpio = priv->gc.ngpio;
288	int i;
289
290	irq_set_chip_and_handler(irq, NULL, NULL);
291	irq_set_chip_data(irq, NULL);
292
293	raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
294
295	/* Free underlying irq if last user unmapped */
296	index = -1;
297	for (i = 0; i < ngpio; i++) {
298		lirq = &priv->lirqs[i];
299		if (lirq->irq == irq) {
300			grgpio_set_imask(priv, i, 0);
301			lirq->irq = 0;
302			index = lirq->index;
303			break;
304		}
305	}
306	WARN_ON(index < 0);
307
308	if (index >= 0) {
309		uirq = &priv->uirqs[lirq->index];
310		uirq->refcnt--;
311		if (uirq->refcnt == 0) {
312			raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
313			free_irq(uirq->uirq, priv);
314			return;
315		}
316	}
317
318	raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
319}
320
321static void grgpio_irq_domain_remove(void *data)
322{
323	struct irq_domain *domain = data;
324
325	irq_domain_remove(domain);
326}
327
328static const struct irq_domain_ops grgpio_irq_domain_ops = {
329	.map	= grgpio_irq_map,
330	.unmap	= grgpio_irq_unmap,
331};
332
333/* ------------------------------------------------------------ */
334
335static int grgpio_probe(struct platform_device *ofdev)
336{
337	struct device_node *np = ofdev->dev.of_node;
338	struct device *dev = &ofdev->dev;
339	void  __iomem *regs;
340	struct gpio_chip *gc;
341	struct grgpio_priv *priv;
342	int err;
343	u32 prop;
344	s32 *irqmap;
345	int size;
346	int i;
347
348	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
349	if (!priv)
350		return -ENOMEM;
351
352	regs = devm_platform_ioremap_resource(ofdev, 0);
353	if (IS_ERR(regs))
354		return PTR_ERR(regs);
355
356	gc = &priv->gc;
357	err = bgpio_init(gc, dev, 4, regs + GRGPIO_DATA,
358			 regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL,
359			 BGPIOF_BIG_ENDIAN_BYTE_ORDER);
360	if (err) {
361		dev_err(dev, "bgpio_init() failed\n");
362		return err;
363	}
364
365	priv->regs = regs;
366	priv->imask = gc->read_reg(regs + GRGPIO_IMASK);
367	priv->dev = dev;
368
 
369	gc->owner = THIS_MODULE;
370	gc->to_irq = grgpio_to_irq;
371	gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", np);
372	if (!gc->label)
373		return -ENOMEM;
374
375	gc->base = -1;
376
377	err = of_property_read_u32(np, "nbits", &prop);
378	if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) {
379		gc->ngpio = GRGPIO_MAX_NGPIO;
380		dev_dbg(dev, "No or invalid nbits property: assume %d\n",
381			gc->ngpio);
382	} else {
383		gc->ngpio = prop;
384	}
385
386	/*
387	 * The irqmap contains the index values indicating which underlying irq,
388	 * if anyone, is connected to that line
389	 */
390	irqmap = (s32 *)of_get_property(np, "irqmap", &size);
391	if (irqmap) {
392		if (size < gc->ngpio) {
393			dev_err(dev,
394				"irqmap shorter than ngpio (%d < %d)\n",
395				size, gc->ngpio);
396			return -EINVAL;
397		}
398
399		priv->domain = irq_domain_add_linear(np, gc->ngpio,
400						     &grgpio_irq_domain_ops,
401						     priv);
402		if (!priv->domain) {
403			dev_err(dev, "Could not add irq domain\n");
404			return -EINVAL;
405		}
406
407		err = devm_add_action_or_reset(dev, grgpio_irq_domain_remove,
408					       priv->domain);
409		if (err)
410			return err;
411
412		for (i = 0; i < gc->ngpio; i++) {
413			struct grgpio_lirq *lirq;
414			int ret;
415
416			lirq = &priv->lirqs[i];
417			lirq->index = irqmap[i];
418
419			if (lirq->index < 0)
420				continue;
421
422			ret = platform_get_irq(ofdev, lirq->index);
423			if (ret <= 0) {
424				/*
425				 * Continue without irq functionality for that
426				 * gpio line
427				 */
428				continue;
429			}
430			priv->uirqs[lirq->index].uirq = ret;
431		}
432	}
433
434	err = devm_gpiochip_add_data(dev, gc, priv);
 
 
435	if (err) {
436		dev_err(dev, "Could not add gpiochip\n");
 
 
437		return err;
438	}
439
440	dev_info(dev, "regs=0x%p, base=%d, ngpio=%d, irqs=%s\n",
441		 priv->regs, gc->base, gc->ngpio, priv->domain ? "on" : "off");
442
443	return 0;
444}
445
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
446static const struct of_device_id grgpio_match[] = {
447	{.name = "GAISLER_GPIO"},
448	{.name = "01_01a"},
449	{},
450};
451
452MODULE_DEVICE_TABLE(of, grgpio_match);
453
454static struct platform_driver grgpio_driver = {
455	.driver = {
456		.name = "grgpio",
457		.of_match_table = grgpio_match,
458	},
459	.probe = grgpio_probe,
 
460};
461module_platform_driver(grgpio_driver);
462
463MODULE_AUTHOR("Aeroflex Gaisler AB.");
464MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO");
465MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores.
  4 *
  5 * 2013 (c) Aeroflex Gaisler AB
  6 *
  7 * This driver supports the GRGPIO GPIO core available in the GRLIB VHDL
  8 * IP core library.
  9 *
 10 * Full documentation of the GRGPIO core can be found here:
 11 * http://www.gaisler.com/products/grlib/grip.pdf
 12 *
 13 * See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for
 14 * information on open firmware properties.
 15 *
 16 * Contributors: Andreas Larsson <andreas@gaisler.com>
 17 */
 18
 
 
 
 
 
 
 
 
 19#include <linux/kernel.h>
 20#include <linux/module.h>
 21#include <linux/init.h>
 22#include <linux/spinlock.h>
 23#include <linux/io.h>
 24#include <linux/of.h>
 25#include <linux/of_platform.h>
 26#include <linux/gpio/driver.h>
 27#include <linux/slab.h>
 28#include <linux/err.h>
 29#include <linux/interrupt.h>
 30#include <linux/irq.h>
 31#include <linux/irqdomain.h>
 32#include <linux/bitops.h>
 33
 34#define GRGPIO_MAX_NGPIO 32
 35
 36#define GRGPIO_DATA		0x00
 37#define GRGPIO_OUTPUT		0x04
 38#define GRGPIO_DIR		0x08
 39#define GRGPIO_IMASK		0x0c
 40#define GRGPIO_IPOL		0x10
 41#define GRGPIO_IEDGE		0x14
 42#define GRGPIO_BYPASS		0x18
 43#define GRGPIO_IMAP_BASE	0x20
 44
 45/* Structure for an irq of the core - called an underlying irq */
 46struct grgpio_uirq {
 47	u8 refcnt; /* Reference counter to manage requesting/freeing of uirq */
 48	u8 uirq; /* Underlying irq of the gpio driver */
 49};
 50
 51/*
 52 * Structure for an irq of a gpio line handed out by this driver. The index is
 53 * used to map to the corresponding underlying irq.
 54 */
 55struct grgpio_lirq {
 56	s8 index; /* Index into struct grgpio_priv's uirqs, or -1 */
 57	u8 irq; /* irq for the gpio line */
 58};
 59
 60struct grgpio_priv {
 61	struct gpio_chip gc;
 62	void __iomem *regs;
 63	struct device *dev;
 64
 65	u32 imask; /* irq mask shadow register */
 66
 67	/*
 68	 * The grgpio core can have multiple "underlying" irqs. The gpio lines
 69	 * can be mapped to any one or none of these underlying irqs
 70	 * independently of each other. This driver sets up an irq domain and
 71	 * hands out separate irqs to each gpio line
 72	 */
 73	struct irq_domain *domain;
 74
 75	/*
 76	 * This array contains information on each underlying irq, each
 77	 * irq of the grgpio core itself.
 78	 */
 79	struct grgpio_uirq uirqs[GRGPIO_MAX_NGPIO];
 80
 81	/*
 82	 * This array contains information for each gpio line on the irqs
 83	 * obtains from this driver. An index value of -1 for a certain gpio
 84	 * line indicates that the line has no irq. Otherwise the index connects
 85	 * the irq to the underlying irq by pointing into the uirqs array.
 86	 */
 87	struct grgpio_lirq lirqs[GRGPIO_MAX_NGPIO];
 88};
 89
 90static void grgpio_set_imask(struct grgpio_priv *priv, unsigned int offset,
 91			     int val)
 92{
 93	struct gpio_chip *gc = &priv->gc;
 94
 95	if (val)
 96		priv->imask |= BIT(offset);
 97	else
 98		priv->imask &= ~BIT(offset);
 99	gc->write_reg(priv->regs + GRGPIO_IMASK, priv->imask);
100}
101
102static int grgpio_to_irq(struct gpio_chip *gc, unsigned offset)
103{
104	struct grgpio_priv *priv = gpiochip_get_data(gc);
105
106	if (offset >= gc->ngpio)
107		return -ENXIO;
108
109	if (priv->lirqs[offset].index < 0)
110		return -ENXIO;
111
112	return irq_create_mapping(priv->domain, offset);
113}
114
115/* -------------------- IRQ chip functions -------------------- */
116
117static int grgpio_irq_set_type(struct irq_data *d, unsigned int type)
118{
119	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
120	unsigned long flags;
121	u32 mask = BIT(d->hwirq);
122	u32 ipol;
123	u32 iedge;
124	u32 pol;
125	u32 edge;
126
127	switch (type) {
128	case IRQ_TYPE_LEVEL_LOW:
129		pol = 0;
130		edge = 0;
131		break;
132	case IRQ_TYPE_LEVEL_HIGH:
133		pol = mask;
134		edge = 0;
135		break;
136	case IRQ_TYPE_EDGE_FALLING:
137		pol = 0;
138		edge = mask;
139		break;
140	case IRQ_TYPE_EDGE_RISING:
141		pol = mask;
142		edge = mask;
143		break;
144	default:
145		return -EINVAL;
146	}
147
148	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
149
150	ipol = priv->gc.read_reg(priv->regs + GRGPIO_IPOL) & ~mask;
151	iedge = priv->gc.read_reg(priv->regs + GRGPIO_IEDGE) & ~mask;
152
153	priv->gc.write_reg(priv->regs + GRGPIO_IPOL, ipol | pol);
154	priv->gc.write_reg(priv->regs + GRGPIO_IEDGE, iedge | edge);
155
156	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
157
158	return 0;
159}
160
161static void grgpio_irq_mask(struct irq_data *d)
162{
163	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
164	int offset = d->hwirq;
165	unsigned long flags;
166
167	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
168
169	grgpio_set_imask(priv, offset, 0);
170
171	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
172}
173
174static void grgpio_irq_unmask(struct irq_data *d)
175{
176	struct grgpio_priv *priv = irq_data_get_irq_chip_data(d);
177	int offset = d->hwirq;
178	unsigned long flags;
179
180	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
181
182	grgpio_set_imask(priv, offset, 1);
183
184	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
185}
186
187static struct irq_chip grgpio_irq_chip = {
188	.name			= "grgpio",
189	.irq_mask		= grgpio_irq_mask,
190	.irq_unmask		= grgpio_irq_unmask,
191	.irq_set_type		= grgpio_irq_set_type,
192};
193
194static irqreturn_t grgpio_irq_handler(int irq, void *dev)
195{
196	struct grgpio_priv *priv = dev;
197	int ngpio = priv->gc.ngpio;
198	unsigned long flags;
199	int i;
200	int match = 0;
201
202	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
203
204	/*
205	 * For each gpio line, call its interrupt handler if it its underlying
206	 * irq matches the current irq that is handled.
207	 */
208	for (i = 0; i < ngpio; i++) {
209		struct grgpio_lirq *lirq = &priv->lirqs[i];
210
211		if (priv->imask & BIT(i) && lirq->index >= 0 &&
212		    priv->uirqs[lirq->index].uirq == irq) {
213			generic_handle_irq(lirq->irq);
214			match = 1;
215		}
216	}
217
218	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
219
220	if (!match)
221		dev_warn(priv->dev, "No gpio line matched irq %d\n", irq);
222
223	return IRQ_HANDLED;
224}
225
226/*
227 * This function will be called as a consequence of the call to
228 * irq_create_mapping in grgpio_to_irq
229 */
230static int grgpio_irq_map(struct irq_domain *d, unsigned int irq,
231			  irq_hw_number_t hwirq)
232{
233	struct grgpio_priv *priv = d->host_data;
234	struct grgpio_lirq *lirq;
235	struct grgpio_uirq *uirq;
236	unsigned long flags;
237	int offset = hwirq;
238	int ret = 0;
239
240	if (!priv)
241		return -EINVAL;
242
243	lirq = &priv->lirqs[offset];
244	if (lirq->index < 0)
245		return -EINVAL;
246
247	dev_dbg(priv->dev, "Mapping irq %d for gpio line %d\n",
248		irq, offset);
249
250	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
251
252	/* Request underlying irq if not already requested */
253	lirq->irq = irq;
254	uirq = &priv->uirqs[lirq->index];
255	if (uirq->refcnt == 0) {
 
256		ret = request_irq(uirq->uirq, grgpio_irq_handler, 0,
257				  dev_name(priv->dev), priv);
258		if (ret) {
259			dev_err(priv->dev,
260				"Could not request underlying irq %d\n",
261				uirq->uirq);
262
263			spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
264
265			return ret;
266		}
 
267	}
268	uirq->refcnt++;
269
270	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
271
272	/* Setup irq  */
273	irq_set_chip_data(irq, priv);
274	irq_set_chip_and_handler(irq, &grgpio_irq_chip,
275				 handle_simple_irq);
276	irq_set_noprobe(irq);
277
278	return ret;
279}
280
281static void grgpio_irq_unmap(struct irq_domain *d, unsigned int irq)
282{
283	struct grgpio_priv *priv = d->host_data;
284	int index;
285	struct grgpio_lirq *lirq;
286	struct grgpio_uirq *uirq;
287	unsigned long flags;
288	int ngpio = priv->gc.ngpio;
289	int i;
290
291	irq_set_chip_and_handler(irq, NULL, NULL);
292	irq_set_chip_data(irq, NULL);
293
294	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
295
296	/* Free underlying irq if last user unmapped */
297	index = -1;
298	for (i = 0; i < ngpio; i++) {
299		lirq = &priv->lirqs[i];
300		if (lirq->irq == irq) {
301			grgpio_set_imask(priv, i, 0);
302			lirq->irq = 0;
303			index = lirq->index;
304			break;
305		}
306	}
307	WARN_ON(index < 0);
308
309	if (index >= 0) {
310		uirq = &priv->uirqs[lirq->index];
311		uirq->refcnt--;
312		if (uirq->refcnt == 0)
 
313			free_irq(uirq->uirq, priv);
 
 
314	}
315
316	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
 
 
 
 
 
 
 
317}
318
319static const struct irq_domain_ops grgpio_irq_domain_ops = {
320	.map	= grgpio_irq_map,
321	.unmap	= grgpio_irq_unmap,
322};
323
324/* ------------------------------------------------------------ */
325
326static int grgpio_probe(struct platform_device *ofdev)
327{
328	struct device_node *np = ofdev->dev.of_node;
 
329	void  __iomem *regs;
330	struct gpio_chip *gc;
331	struct grgpio_priv *priv;
332	int err;
333	u32 prop;
334	s32 *irqmap;
335	int size;
336	int i;
337
338	priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
339	if (!priv)
340		return -ENOMEM;
341
342	regs = devm_platform_ioremap_resource(ofdev, 0);
343	if (IS_ERR(regs))
344		return PTR_ERR(regs);
345
346	gc = &priv->gc;
347	err = bgpio_init(gc, &ofdev->dev, 4, regs + GRGPIO_DATA,
348			 regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL,
349			 BGPIOF_BIG_ENDIAN_BYTE_ORDER);
350	if (err) {
351		dev_err(&ofdev->dev, "bgpio_init() failed\n");
352		return err;
353	}
354
355	priv->regs = regs;
356	priv->imask = gc->read_reg(regs + GRGPIO_IMASK);
357	priv->dev = &ofdev->dev;
358
359	gc->of_node = np;
360	gc->owner = THIS_MODULE;
361	gc->to_irq = grgpio_to_irq;
362	gc->label = devm_kasprintf(&ofdev->dev, GFP_KERNEL, "%pOF", np);
 
 
 
363	gc->base = -1;
364
365	err = of_property_read_u32(np, "nbits", &prop);
366	if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) {
367		gc->ngpio = GRGPIO_MAX_NGPIO;
368		dev_dbg(&ofdev->dev,
369			"No or invalid nbits property: assume %d\n", gc->ngpio);
370	} else {
371		gc->ngpio = prop;
372	}
373
374	/*
375	 * The irqmap contains the index values indicating which underlying irq,
376	 * if anyone, is connected to that line
377	 */
378	irqmap = (s32 *)of_get_property(np, "irqmap", &size);
379	if (irqmap) {
380		if (size < gc->ngpio) {
381			dev_err(&ofdev->dev,
382				"irqmap shorter than ngpio (%d < %d)\n",
383				size, gc->ngpio);
384			return -EINVAL;
385		}
386
387		priv->domain = irq_domain_add_linear(np, gc->ngpio,
388						     &grgpio_irq_domain_ops,
389						     priv);
390		if (!priv->domain) {
391			dev_err(&ofdev->dev, "Could not add irq domain\n");
392			return -EINVAL;
393		}
394
 
 
 
 
 
395		for (i = 0; i < gc->ngpio; i++) {
396			struct grgpio_lirq *lirq;
397			int ret;
398
399			lirq = &priv->lirqs[i];
400			lirq->index = irqmap[i];
401
402			if (lirq->index < 0)
403				continue;
404
405			ret = platform_get_irq(ofdev, lirq->index);
406			if (ret <= 0) {
407				/*
408				 * Continue without irq functionality for that
409				 * gpio line
410				 */
411				continue;
412			}
413			priv->uirqs[lirq->index].uirq = ret;
414		}
415	}
416
417	platform_set_drvdata(ofdev, priv);
418
419	err = gpiochip_add_data(gc, priv);
420	if (err) {
421		dev_err(&ofdev->dev, "Could not add gpiochip\n");
422		if (priv->domain)
423			irq_domain_remove(priv->domain);
424		return err;
425	}
426
427	dev_info(&ofdev->dev, "regs=0x%p, base=%d, ngpio=%d, irqs=%s\n",
428		 priv->regs, gc->base, gc->ngpio, priv->domain ? "on" : "off");
429
430	return 0;
431}
432
433static int grgpio_remove(struct platform_device *ofdev)
434{
435	struct grgpio_priv *priv = platform_get_drvdata(ofdev);
436	unsigned long flags;
437	int i;
438	int ret = 0;
439
440	spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
441
442	if (priv->domain) {
443		for (i = 0; i < GRGPIO_MAX_NGPIO; i++) {
444			if (priv->uirqs[i].refcnt != 0) {
445				ret = -EBUSY;
446				goto out;
447			}
448		}
449	}
450
451	gpiochip_remove(&priv->gc);
452
453	if (priv->domain)
454		irq_domain_remove(priv->domain);
455
456out:
457	spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags);
458
459	return ret;
460}
461
462static const struct of_device_id grgpio_match[] = {
463	{.name = "GAISLER_GPIO"},
464	{.name = "01_01a"},
465	{},
466};
467
468MODULE_DEVICE_TABLE(of, grgpio_match);
469
470static struct platform_driver grgpio_driver = {
471	.driver = {
472		.name = "grgpio",
473		.of_match_table = grgpio_match,
474	},
475	.probe = grgpio_probe,
476	.remove = grgpio_remove,
477};
478module_platform_driver(grgpio_driver);
479
480MODULE_AUTHOR("Aeroflex Gaisler AB.");
481MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO");
482MODULE_LICENSE("GPL");