xref: /linux/drivers/gpio/gpio-mxc.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
3  * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
4  *
5  * Based on code from Freescale,
6  * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2
11  * of the License, or (at your option) any later version.
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
20  */
21 
22 #include <linux/err.h>
23 #include <linux/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/irqdomain.h>
28 #include <linux/irqchip/chained_irq.h>
29 #include <linux/gpio.h>
30 #include <linux/platform_device.h>
31 #include <linux/slab.h>
32 #include <linux/basic_mmio_gpio.h>
33 #include <linux/of.h>
34 #include <linux/of_device.h>
35 #include <linux/module.h>
36 #include <asm-generic/bug.h>
37 
38 enum mxc_gpio_hwtype {
39 	IMX1_GPIO,	/* runs on i.mx1 */
40 	IMX21_GPIO,	/* runs on i.mx21 and i.mx27 */
41 	IMX31_GPIO,	/* runs on i.mx31 */
42 	IMX35_GPIO,	/* runs on all other i.mx */
43 };
44 
45 /* device type dependent stuff */
46 struct mxc_gpio_hwdata {
47 	unsigned dr_reg;
48 	unsigned gdir_reg;
49 	unsigned psr_reg;
50 	unsigned icr1_reg;
51 	unsigned icr2_reg;
52 	unsigned imr_reg;
53 	unsigned isr_reg;
54 	int edge_sel_reg;
55 	unsigned low_level;
56 	unsigned high_level;
57 	unsigned rise_edge;
58 	unsigned fall_edge;
59 };
60 
61 struct mxc_gpio_port {
62 	struct list_head node;
63 	void __iomem *base;
64 	int irq;
65 	int irq_high;
66 	struct irq_domain *domain;
67 	struct bgpio_chip bgc;
68 	u32 both_edges;
69 };
70 
71 static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = {
72 	.dr_reg		= 0x1c,
73 	.gdir_reg	= 0x00,
74 	.psr_reg	= 0x24,
75 	.icr1_reg	= 0x28,
76 	.icr2_reg	= 0x2c,
77 	.imr_reg	= 0x30,
78 	.isr_reg	= 0x34,
79 	.edge_sel_reg	= -EINVAL,
80 	.low_level	= 0x03,
81 	.high_level	= 0x02,
82 	.rise_edge	= 0x00,
83 	.fall_edge	= 0x01,
84 };
85 
86 static struct mxc_gpio_hwdata imx31_gpio_hwdata = {
87 	.dr_reg		= 0x00,
88 	.gdir_reg	= 0x04,
89 	.psr_reg	= 0x08,
90 	.icr1_reg	= 0x0c,
91 	.icr2_reg	= 0x10,
92 	.imr_reg	= 0x14,
93 	.isr_reg	= 0x18,
94 	.edge_sel_reg	= -EINVAL,
95 	.low_level	= 0x00,
96 	.high_level	= 0x01,
97 	.rise_edge	= 0x02,
98 	.fall_edge	= 0x03,
99 };
100 
101 static struct mxc_gpio_hwdata imx35_gpio_hwdata = {
102 	.dr_reg		= 0x00,
103 	.gdir_reg	= 0x04,
104 	.psr_reg	= 0x08,
105 	.icr1_reg	= 0x0c,
106 	.icr2_reg	= 0x10,
107 	.imr_reg	= 0x14,
108 	.isr_reg	= 0x18,
109 	.edge_sel_reg	= 0x1c,
110 	.low_level	= 0x00,
111 	.high_level	= 0x01,
112 	.rise_edge	= 0x02,
113 	.fall_edge	= 0x03,
114 };
115 
116 static enum mxc_gpio_hwtype mxc_gpio_hwtype;
117 static struct mxc_gpio_hwdata *mxc_gpio_hwdata;
118 
119 #define GPIO_DR			(mxc_gpio_hwdata->dr_reg)
120 #define GPIO_GDIR		(mxc_gpio_hwdata->gdir_reg)
121 #define GPIO_PSR		(mxc_gpio_hwdata->psr_reg)
122 #define GPIO_ICR1		(mxc_gpio_hwdata->icr1_reg)
123 #define GPIO_ICR2		(mxc_gpio_hwdata->icr2_reg)
124 #define GPIO_IMR		(mxc_gpio_hwdata->imr_reg)
125 #define GPIO_ISR		(mxc_gpio_hwdata->isr_reg)
126 #define GPIO_EDGE_SEL		(mxc_gpio_hwdata->edge_sel_reg)
127 
128 #define GPIO_INT_LOW_LEV	(mxc_gpio_hwdata->low_level)
129 #define GPIO_INT_HIGH_LEV	(mxc_gpio_hwdata->high_level)
130 #define GPIO_INT_RISE_EDGE	(mxc_gpio_hwdata->rise_edge)
131 #define GPIO_INT_FALL_EDGE	(mxc_gpio_hwdata->fall_edge)
132 #define GPIO_INT_BOTH_EDGES	0x4
133 
134 static const struct platform_device_id mxc_gpio_devtype[] = {
135 	{
136 		.name = "imx1-gpio",
137 		.driver_data = IMX1_GPIO,
138 	}, {
139 		.name = "imx21-gpio",
140 		.driver_data = IMX21_GPIO,
141 	}, {
142 		.name = "imx31-gpio",
143 		.driver_data = IMX31_GPIO,
144 	}, {
145 		.name = "imx35-gpio",
146 		.driver_data = IMX35_GPIO,
147 	}, {
148 		/* sentinel */
149 	}
150 };
151 
152 static const struct of_device_id mxc_gpio_dt_ids[] = {
153 	{ .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], },
154 	{ .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], },
155 	{ .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], },
156 	{ .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], },
157 	{ /* sentinel */ }
158 };
159 
160 /*
161  * MX2 has one interrupt *for all* gpio ports. The list is used
162  * to save the references to all ports, so that mx2_gpio_irq_handler
163  * can walk through all interrupt status registers.
164  */
165 static LIST_HEAD(mxc_gpio_ports);
166 
167 /* Note: This driver assumes 32 GPIOs are handled in one register */
168 
169 static int gpio_set_irq_type(struct irq_data *d, u32 type)
170 {
171 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
172 	struct mxc_gpio_port *port = gc->private;
173 	u32 bit, val;
174 	u32 gpio_idx = d->hwirq;
175 	u32 gpio = port->bgc.gc.base + gpio_idx;
176 	int edge;
177 	void __iomem *reg = port->base;
178 
179 	port->both_edges &= ~(1 << gpio_idx);
180 	switch (type) {
181 	case IRQ_TYPE_EDGE_RISING:
182 		edge = GPIO_INT_RISE_EDGE;
183 		break;
184 	case IRQ_TYPE_EDGE_FALLING:
185 		edge = GPIO_INT_FALL_EDGE;
186 		break;
187 	case IRQ_TYPE_EDGE_BOTH:
188 		if (GPIO_EDGE_SEL >= 0) {
189 			edge = GPIO_INT_BOTH_EDGES;
190 		} else {
191 			val = gpio_get_value(gpio);
192 			if (val) {
193 				edge = GPIO_INT_LOW_LEV;
194 				pr_debug("mxc: set GPIO %d to low trigger\n", gpio);
195 			} else {
196 				edge = GPIO_INT_HIGH_LEV;
197 				pr_debug("mxc: set GPIO %d to high trigger\n", gpio);
198 			}
199 			port->both_edges |= 1 << gpio_idx;
200 		}
201 		break;
202 	case IRQ_TYPE_LEVEL_LOW:
203 		edge = GPIO_INT_LOW_LEV;
204 		break;
205 	case IRQ_TYPE_LEVEL_HIGH:
206 		edge = GPIO_INT_HIGH_LEV;
207 		break;
208 	default:
209 		return -EINVAL;
210 	}
211 
212 	if (GPIO_EDGE_SEL >= 0) {
213 		val = readl(port->base + GPIO_EDGE_SEL);
214 		if (edge == GPIO_INT_BOTH_EDGES)
215 			writel(val | (1 << gpio_idx),
216 				port->base + GPIO_EDGE_SEL);
217 		else
218 			writel(val & ~(1 << gpio_idx),
219 				port->base + GPIO_EDGE_SEL);
220 	}
221 
222 	if (edge != GPIO_INT_BOTH_EDGES) {
223 		reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
224 		bit = gpio_idx & 0xf;
225 		val = readl(reg) & ~(0x3 << (bit << 1));
226 		writel(val | (edge << (bit << 1)), reg);
227 	}
228 
229 	writel(1 << gpio_idx, port->base + GPIO_ISR);
230 
231 	return 0;
232 }
233 
234 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
235 {
236 	void __iomem *reg = port->base;
237 	u32 bit, val;
238 	int edge;
239 
240 	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
241 	bit = gpio & 0xf;
242 	val = readl(reg);
243 	edge = (val >> (bit << 1)) & 3;
244 	val &= ~(0x3 << (bit << 1));
245 	if (edge == GPIO_INT_HIGH_LEV) {
246 		edge = GPIO_INT_LOW_LEV;
247 		pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
248 	} else if (edge == GPIO_INT_LOW_LEV) {
249 		edge = GPIO_INT_HIGH_LEV;
250 		pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
251 	} else {
252 		pr_err("mxc: invalid configuration for GPIO %d: %x\n",
253 		       gpio, edge);
254 		return;
255 	}
256 	writel(val | (edge << (bit << 1)), reg);
257 }
258 
259 /* handle 32 interrupts in one status register */
260 static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
261 {
262 	while (irq_stat != 0) {
263 		int irqoffset = fls(irq_stat) - 1;
264 
265 		if (port->both_edges & (1 << irqoffset))
266 			mxc_flip_edge(port, irqoffset);
267 
268 		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
269 
270 		irq_stat &= ~(1 << irqoffset);
271 	}
272 }
273 
274 /* MX1 and MX3 has one interrupt *per* gpio port */
275 static void mx3_gpio_irq_handler(struct irq_desc *desc)
276 {
277 	u32 irq_stat;
278 	struct mxc_gpio_port *port = irq_desc_get_handler_data(desc);
279 	struct irq_chip *chip = irq_desc_get_chip(desc);
280 
281 	chained_irq_enter(chip, desc);
282 
283 	irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
284 
285 	mxc_gpio_irq_handler(port, irq_stat);
286 
287 	chained_irq_exit(chip, desc);
288 }
289 
290 /* MX2 has one interrupt *for all* gpio ports */
291 static void mx2_gpio_irq_handler(struct irq_desc *desc)
292 {
293 	u32 irq_msk, irq_stat;
294 	struct mxc_gpio_port *port;
295 	struct irq_chip *chip = irq_desc_get_chip(desc);
296 
297 	chained_irq_enter(chip, desc);
298 
299 	/* walk through all interrupt status registers */
300 	list_for_each_entry(port, &mxc_gpio_ports, node) {
301 		irq_msk = readl(port->base + GPIO_IMR);
302 		if (!irq_msk)
303 			continue;
304 
305 		irq_stat = readl(port->base + GPIO_ISR) & irq_msk;
306 		if (irq_stat)
307 			mxc_gpio_irq_handler(port, irq_stat);
308 	}
309 	chained_irq_exit(chip, desc);
310 }
311 
312 /*
313  * Set interrupt number "irq" in the GPIO as a wake-up source.
314  * While system is running, all registered GPIO interrupts need to have
315  * wake-up enabled. When system is suspended, only selected GPIO interrupts
316  * need to have wake-up enabled.
317  * @param  irq          interrupt source number
318  * @param  enable       enable as wake-up if equal to non-zero
319  * @return       This function returns 0 on success.
320  */
321 static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
322 {
323 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
324 	struct mxc_gpio_port *port = gc->private;
325 	u32 gpio_idx = d->hwirq;
326 
327 	if (enable) {
328 		if (port->irq_high && (gpio_idx >= 16))
329 			enable_irq_wake(port->irq_high);
330 		else
331 			enable_irq_wake(port->irq);
332 	} else {
333 		if (port->irq_high && (gpio_idx >= 16))
334 			disable_irq_wake(port->irq_high);
335 		else
336 			disable_irq_wake(port->irq);
337 	}
338 
339 	return 0;
340 }
341 
342 static int mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base)
343 {
344 	struct irq_chip_generic *gc;
345 	struct irq_chip_type *ct;
346 
347 	gc = irq_alloc_generic_chip("gpio-mxc", 1, irq_base,
348 				    port->base, handle_level_irq);
349 	if (!gc)
350 		return -ENOMEM;
351 	gc->private = port;
352 
353 	ct = gc->chip_types;
354 	ct->chip.irq_ack = irq_gc_ack_set_bit;
355 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
356 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
357 	ct->chip.irq_set_type = gpio_set_irq_type;
358 	ct->chip.irq_set_wake = gpio_set_wake_irq;
359 	ct->chip.flags = IRQCHIP_MASK_ON_SUSPEND;
360 	ct->regs.ack = GPIO_ISR;
361 	ct->regs.mask = GPIO_IMR;
362 
363 	irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK,
364 			       IRQ_NOREQUEST, 0);
365 
366 	return 0;
367 }
368 
369 static void mxc_gpio_get_hw(struct platform_device *pdev)
370 {
371 	const struct of_device_id *of_id =
372 			of_match_device(mxc_gpio_dt_ids, &pdev->dev);
373 	enum mxc_gpio_hwtype hwtype;
374 
375 	if (of_id)
376 		pdev->id_entry = of_id->data;
377 	hwtype = pdev->id_entry->driver_data;
378 
379 	if (mxc_gpio_hwtype) {
380 		/*
381 		 * The driver works with a reasonable presupposition,
382 		 * that is all gpio ports must be the same type when
383 		 * running on one soc.
384 		 */
385 		BUG_ON(mxc_gpio_hwtype != hwtype);
386 		return;
387 	}
388 
389 	if (hwtype == IMX35_GPIO)
390 		mxc_gpio_hwdata = &imx35_gpio_hwdata;
391 	else if (hwtype == IMX31_GPIO)
392 		mxc_gpio_hwdata = &imx31_gpio_hwdata;
393 	else
394 		mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
395 
396 	mxc_gpio_hwtype = hwtype;
397 }
398 
399 static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
400 {
401 	struct bgpio_chip *bgc = to_bgpio_chip(gc);
402 	struct mxc_gpio_port *port =
403 		container_of(bgc, struct mxc_gpio_port, bgc);
404 
405 	return irq_find_mapping(port->domain, offset);
406 }
407 
408 static int mxc_gpio_probe(struct platform_device *pdev)
409 {
410 	struct device_node *np = pdev->dev.of_node;
411 	struct mxc_gpio_port *port;
412 	struct resource *iores;
413 	int irq_base;
414 	int err;
415 
416 	mxc_gpio_get_hw(pdev);
417 
418 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
419 	if (!port)
420 		return -ENOMEM;
421 
422 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
423 	port->base = devm_ioremap_resource(&pdev->dev, iores);
424 	if (IS_ERR(port->base))
425 		return PTR_ERR(port->base);
426 
427 	port->irq_high = platform_get_irq(pdev, 1);
428 	port->irq = platform_get_irq(pdev, 0);
429 	if (port->irq < 0)
430 		return port->irq;
431 
432 	/* disable the interrupt and clear the status */
433 	writel(0, port->base + GPIO_IMR);
434 	writel(~0, port->base + GPIO_ISR);
435 
436 	if (mxc_gpio_hwtype == IMX21_GPIO) {
437 		/*
438 		 * Setup one handler for all GPIO interrupts. Actually setting
439 		 * the handler is needed only once, but doing it for every port
440 		 * is more robust and easier.
441 		 */
442 		irq_set_chained_handler(port->irq, mx2_gpio_irq_handler);
443 	} else {
444 		/* setup one handler for each entry */
445 		irq_set_chained_handler_and_data(port->irq,
446 						 mx3_gpio_irq_handler, port);
447 		if (port->irq_high > 0)
448 			/* setup handler for GPIO 16 to 31 */
449 			irq_set_chained_handler_and_data(port->irq_high,
450 							 mx3_gpio_irq_handler,
451 							 port);
452 	}
453 
454 	err = bgpio_init(&port->bgc, &pdev->dev, 4,
455 			 port->base + GPIO_PSR,
456 			 port->base + GPIO_DR, NULL,
457 			 port->base + GPIO_GDIR, NULL,
458 			 BGPIOF_READ_OUTPUT_REG_SET);
459 	if (err)
460 		goto out_bgio;
461 
462 	port->bgc.gc.to_irq = mxc_gpio_to_irq;
463 	port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
464 					     pdev->id * 32;
465 
466 	err = gpiochip_add(&port->bgc.gc);
467 	if (err)
468 		goto out_bgpio_remove;
469 
470 	irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
471 	if (irq_base < 0) {
472 		err = irq_base;
473 		goto out_gpiochip_remove;
474 	}
475 
476 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
477 					     &irq_domain_simple_ops, NULL);
478 	if (!port->domain) {
479 		err = -ENODEV;
480 		goto out_irqdesc_free;
481 	}
482 
483 	/* gpio-mxc can be a generic irq chip */
484 	err = mxc_gpio_init_gc(port, irq_base);
485 	if (err < 0)
486 		goto out_irqdomain_remove;
487 
488 	list_add_tail(&port->node, &mxc_gpio_ports);
489 
490 	return 0;
491 
492 out_irqdomain_remove:
493 	irq_domain_remove(port->domain);
494 out_irqdesc_free:
495 	irq_free_descs(irq_base, 32);
496 out_gpiochip_remove:
497 	gpiochip_remove(&port->bgc.gc);
498 out_bgpio_remove:
499 	bgpio_remove(&port->bgc);
500 out_bgio:
501 	dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
502 	return err;
503 }
504 
505 static struct platform_driver mxc_gpio_driver = {
506 	.driver		= {
507 		.name	= "gpio-mxc",
508 		.of_match_table = mxc_gpio_dt_ids,
509 	},
510 	.probe		= mxc_gpio_probe,
511 	.id_table	= mxc_gpio_devtype,
512 };
513 
514 static int __init gpio_mxc_init(void)
515 {
516 	return platform_driver_register(&mxc_gpio_driver);
517 }
518 postcore_initcall(gpio_mxc_init);
519 
520 MODULE_AUTHOR("Freescale Semiconductor, "
521 	      "Daniel Mack <danielncaiaq.de>, "
522 	      "Juergen Beisert <kernel@pengutronix.de>");
523 MODULE_DESCRIPTION("Freescale MXC GPIO");
524 MODULE_LICENSE("GPL");
525