xref: /linux/drivers/gpio/gpio-mxs.c (revision 56bbd86257f899ced7ef9c58210dda4edbd40871)
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,
20  * MA  02110-1301, USA.
21  */
22 
23 #include <linux/err.h>
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/io.h>
27 #include <linux/irq.h>
28 #include <linux/irqdomain.h>
29 #include <linux/of.h>
30 #include <linux/of_address.h>
31 #include <linux/of_device.h>
32 #include <linux/platform_device.h>
33 #include <linux/slab.h>
34 #include <linux/gpio/driver.h>
35 /* FIXME: for gpio_get_value(), replace this by direct register read */
36 #include <linux/gpio.h>
37 #include <linux/module.h>
38 
39 #define MXS_SET		0x4
40 #define MXS_CLR		0x8
41 
42 #define PINCTRL_DOUT(p)		((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
43 #define PINCTRL_DIN(p)		((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
44 #define PINCTRL_DOE(p)		((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
45 #define PINCTRL_PIN2IRQ(p)	((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
46 #define PINCTRL_IRQEN(p)	((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
47 #define PINCTRL_IRQLEV(p)	((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
48 #define PINCTRL_IRQPOL(p)	((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
49 #define PINCTRL_IRQSTAT(p)	((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
50 
51 #define GPIO_INT_FALL_EDGE	0x0
52 #define GPIO_INT_LOW_LEV	0x1
53 #define GPIO_INT_RISE_EDGE	0x2
54 #define GPIO_INT_HIGH_LEV	0x3
55 #define GPIO_INT_LEV_MASK	(1 << 0)
56 #define GPIO_INT_POL_MASK	(1 << 1)
57 
58 enum mxs_gpio_id {
59 	IMX23_GPIO,
60 	IMX28_GPIO,
61 };
62 
63 struct mxs_gpio_port {
64 	void __iomem *base;
65 	int id;
66 	int irq;
67 	struct irq_domain *domain;
68 	struct gpio_chip gc;
69 	enum mxs_gpio_id devid;
70 	u32 both_edges;
71 };
72 
73 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
74 {
75 	return port->devid == IMX23_GPIO;
76 }
77 
78 static inline int is_imx28_gpio(struct mxs_gpio_port *port)
79 {
80 	return port->devid == IMX28_GPIO;
81 }
82 
83 /* Note: This driver assumes 32 GPIOs are handled in one register */
84 
85 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
86 {
87 	u32 val;
88 	u32 pin_mask = 1 << d->hwirq;
89 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
90 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
91 	struct mxs_gpio_port *port = gc->private;
92 	void __iomem *pin_addr;
93 	int edge;
94 
95 	if (!(ct->type & type))
96 		if (irq_setup_alt_chip(d, type))
97 			return -EINVAL;
98 
99 	port->both_edges &= ~pin_mask;
100 	switch (type) {
101 	case IRQ_TYPE_EDGE_BOTH:
102 		val = gpio_get_value(port->gc.base + d->hwirq);
103 		if (val)
104 			edge = GPIO_INT_FALL_EDGE;
105 		else
106 			edge = GPIO_INT_RISE_EDGE;
107 		port->both_edges |= pin_mask;
108 		break;
109 	case IRQ_TYPE_EDGE_RISING:
110 		edge = GPIO_INT_RISE_EDGE;
111 		break;
112 	case IRQ_TYPE_EDGE_FALLING:
113 		edge = GPIO_INT_FALL_EDGE;
114 		break;
115 	case IRQ_TYPE_LEVEL_LOW:
116 		edge = GPIO_INT_LOW_LEV;
117 		break;
118 	case IRQ_TYPE_LEVEL_HIGH:
119 		edge = GPIO_INT_HIGH_LEV;
120 		break;
121 	default:
122 		return -EINVAL;
123 	}
124 
125 	/* set level or edge */
126 	pin_addr = port->base + PINCTRL_IRQLEV(port);
127 	if (edge & GPIO_INT_LEV_MASK) {
128 		writel(pin_mask, pin_addr + MXS_SET);
129 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
130 	} else {
131 		writel(pin_mask, pin_addr + MXS_CLR);
132 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
133 	}
134 
135 	/* set polarity */
136 	pin_addr = port->base + PINCTRL_IRQPOL(port);
137 	if (edge & GPIO_INT_POL_MASK)
138 		writel(pin_mask, pin_addr + MXS_SET);
139 	else
140 		writel(pin_mask, pin_addr + MXS_CLR);
141 
142 	writel(pin_mask,
143 	       port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
144 
145 	return 0;
146 }
147 
148 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
149 {
150 	u32 bit, val, edge;
151 	void __iomem *pin_addr;
152 
153 	bit = 1 << gpio;
154 
155 	pin_addr = port->base + PINCTRL_IRQPOL(port);
156 	val = readl(pin_addr);
157 	edge = val & bit;
158 
159 	if (edge)
160 		writel(bit, pin_addr + MXS_CLR);
161 	else
162 		writel(bit, pin_addr + MXS_SET);
163 }
164 
165 /* MXS has one interrupt *per* gpio port */
166 static void mxs_gpio_irq_handler(struct irq_desc *desc)
167 {
168 	u32 irq_stat;
169 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
170 
171 	desc->irq_data.chip->irq_ack(&desc->irq_data);
172 
173 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
174 			readl(port->base + PINCTRL_IRQEN(port));
175 
176 	while (irq_stat != 0) {
177 		int irqoffset = fls(irq_stat) - 1;
178 		if (port->both_edges & (1 << irqoffset))
179 			mxs_flip_edge(port, irqoffset);
180 
181 		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
182 		irq_stat &= ~(1 << irqoffset);
183 	}
184 }
185 
186 /*
187  * Set interrupt number "irq" in the GPIO as a wake-up source.
188  * While system is running, all registered GPIO interrupts need to have
189  * wake-up enabled. When system is suspended, only selected GPIO interrupts
190  * need to have wake-up enabled.
191  * @param  irq          interrupt source number
192  * @param  enable       enable as wake-up if equal to non-zero
193  * @return       This function returns 0 on success.
194  */
195 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
196 {
197 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
198 	struct mxs_gpio_port *port = gc->private;
199 
200 	if (enable)
201 		enable_irq_wake(port->irq);
202 	else
203 		disable_irq_wake(port->irq);
204 
205 	return 0;
206 }
207 
208 static int __init mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
209 {
210 	struct irq_chip_generic *gc;
211 	struct irq_chip_type *ct;
212 
213 	gc = irq_alloc_generic_chip("gpio-mxs", 2, irq_base,
214 				    port->base, handle_level_irq);
215 	if (!gc)
216 		return -ENOMEM;
217 
218 	gc->private = port;
219 
220 	ct = &gc->chip_types[0];
221 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
222 	ct->chip.irq_ack = irq_gc_ack_set_bit;
223 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
224 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
225 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
226 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
227 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
228 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
229 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
230 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
231 
232 	ct = &gc->chip_types[1];
233 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
234 	ct->chip.irq_ack = irq_gc_ack_set_bit;
235 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
236 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
237 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
238 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
239 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
240 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
241 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
242 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
243 	ct->handler = handle_level_irq;
244 
245 	irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK,
246 			       IRQ_NOREQUEST, 0);
247 
248 	return 0;
249 }
250 
251 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
252 {
253 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
254 
255 	return irq_find_mapping(port->domain, offset);
256 }
257 
258 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
259 {
260 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
261 	u32 mask = 1 << offset;
262 	u32 dir;
263 
264 	dir = readl(port->base + PINCTRL_DOE(port));
265 	return !(dir & mask);
266 }
267 
268 static const struct platform_device_id mxs_gpio_ids[] = {
269 	{
270 		.name = "imx23-gpio",
271 		.driver_data = IMX23_GPIO,
272 	}, {
273 		.name = "imx28-gpio",
274 		.driver_data = IMX28_GPIO,
275 	}, {
276 		/* sentinel */
277 	}
278 };
279 MODULE_DEVICE_TABLE(platform, mxs_gpio_ids);
280 
281 static const struct of_device_id mxs_gpio_dt_ids[] = {
282 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
283 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
284 	{ /* sentinel */ }
285 };
286 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
287 
288 static int mxs_gpio_probe(struct platform_device *pdev)
289 {
290 	const struct of_device_id *of_id =
291 			of_match_device(mxs_gpio_dt_ids, &pdev->dev);
292 	struct device_node *np = pdev->dev.of_node;
293 	struct device_node *parent;
294 	static void __iomem *base;
295 	struct mxs_gpio_port *port;
296 	int irq_base;
297 	int err;
298 
299 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
300 	if (!port)
301 		return -ENOMEM;
302 
303 	port->id = of_alias_get_id(np, "gpio");
304 	if (port->id < 0)
305 		return port->id;
306 	port->devid = (enum mxs_gpio_id) of_id->data;
307 	port->irq = platform_get_irq(pdev, 0);
308 	if (port->irq < 0)
309 		return port->irq;
310 
311 	/*
312 	 * map memory region only once, as all the gpio ports
313 	 * share the same one
314 	 */
315 	if (!base) {
316 		parent = of_get_parent(np);
317 		base = of_iomap(parent, 0);
318 		of_node_put(parent);
319 		if (!base)
320 			return -EADDRNOTAVAIL;
321 	}
322 	port->base = base;
323 
324 	/* initially disable the interrupts */
325 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
326 	writel(0, port->base + PINCTRL_IRQEN(port));
327 
328 	/* clear address has to be used to clear IRQSTAT bits */
329 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
330 
331 	irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
332 	if (irq_base < 0) {
333 		err = irq_base;
334 		goto out_iounmap;
335 	}
336 
337 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
338 					     &irq_domain_simple_ops, NULL);
339 	if (!port->domain) {
340 		err = -ENODEV;
341 		goto out_irqdesc_free;
342 	}
343 
344 	/* gpio-mxs can be a generic irq chip */
345 	err = mxs_gpio_init_gc(port, irq_base);
346 	if (err < 0)
347 		goto out_irqdomain_remove;
348 
349 	/* setup one handler for each entry */
350 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
351 					 port);
352 
353 	err = bgpio_init(&port->gc, &pdev->dev, 4,
354 			 port->base + PINCTRL_DIN(port),
355 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
356 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
357 			 port->base + PINCTRL_DOE(port), NULL, 0);
358 	if (err)
359 		goto out_irqdomain_remove;
360 
361 	port->gc.to_irq = mxs_gpio_to_irq;
362 	port->gc.get_direction = mxs_gpio_get_direction;
363 	port->gc.base = port->id * 32;
364 
365 	err = gpiochip_add_data(&port->gc, port);
366 	if (err)
367 		goto out_irqdomain_remove;
368 
369 	return 0;
370 
371 out_irqdomain_remove:
372 	irq_domain_remove(port->domain);
373 out_irqdesc_free:
374 	irq_free_descs(irq_base, 32);
375 out_iounmap:
376 	iounmap(port->base);
377 	return err;
378 }
379 
380 static struct platform_driver mxs_gpio_driver = {
381 	.driver		= {
382 		.name	= "gpio-mxs",
383 		.of_match_table = mxs_gpio_dt_ids,
384 	},
385 	.probe		= mxs_gpio_probe,
386 	.id_table	= mxs_gpio_ids,
387 };
388 
389 static int __init mxs_gpio_init(void)
390 {
391 	return platform_driver_register(&mxs_gpio_driver);
392 }
393 postcore_initcall(mxs_gpio_init);
394 
395 MODULE_AUTHOR("Freescale Semiconductor, "
396 	      "Daniel Mack <danielncaiaq.de>, "
397 	      "Juergen Beisert <kernel@pengutronix.de>");
398 MODULE_DESCRIPTION("Freescale MXS GPIO");
399 MODULE_LICENSE("GPL");
400