xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision e3b9f1e8)
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 	struct device *dev;
70 	enum mxs_gpio_id devid;
71 	u32 both_edges;
72 };
73 
74 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
75 {
76 	return port->devid == IMX23_GPIO;
77 }
78 
79 static inline int is_imx28_gpio(struct mxs_gpio_port *port)
80 {
81 	return port->devid == IMX28_GPIO;
82 }
83 
84 /* Note: This driver assumes 32 GPIOs are handled in one register */
85 
86 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
87 {
88 	u32 val;
89 	u32 pin_mask = 1 << d->hwirq;
90 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
91 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
92 	struct mxs_gpio_port *port = gc->private;
93 	void __iomem *pin_addr;
94 	int edge;
95 
96 	if (!(ct->type & type))
97 		if (irq_setup_alt_chip(d, type))
98 			return -EINVAL;
99 
100 	port->both_edges &= ~pin_mask;
101 	switch (type) {
102 	case IRQ_TYPE_EDGE_BOTH:
103 		val = gpio_get_value(port->gc.base + d->hwirq);
104 		if (val)
105 			edge = GPIO_INT_FALL_EDGE;
106 		else
107 			edge = GPIO_INT_RISE_EDGE;
108 		port->both_edges |= pin_mask;
109 		break;
110 	case IRQ_TYPE_EDGE_RISING:
111 		edge = GPIO_INT_RISE_EDGE;
112 		break;
113 	case IRQ_TYPE_EDGE_FALLING:
114 		edge = GPIO_INT_FALL_EDGE;
115 		break;
116 	case IRQ_TYPE_LEVEL_LOW:
117 		edge = GPIO_INT_LOW_LEV;
118 		break;
119 	case IRQ_TYPE_LEVEL_HIGH:
120 		edge = GPIO_INT_HIGH_LEV;
121 		break;
122 	default:
123 		return -EINVAL;
124 	}
125 
126 	/* set level or edge */
127 	pin_addr = port->base + PINCTRL_IRQLEV(port);
128 	if (edge & GPIO_INT_LEV_MASK) {
129 		writel(pin_mask, pin_addr + MXS_SET);
130 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
131 	} else {
132 		writel(pin_mask, pin_addr + MXS_CLR);
133 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
134 	}
135 
136 	/* set polarity */
137 	pin_addr = port->base + PINCTRL_IRQPOL(port);
138 	if (edge & GPIO_INT_POL_MASK)
139 		writel(pin_mask, pin_addr + MXS_SET);
140 	else
141 		writel(pin_mask, pin_addr + MXS_CLR);
142 
143 	writel(pin_mask,
144 	       port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
145 
146 	return 0;
147 }
148 
149 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
150 {
151 	u32 bit, val, edge;
152 	void __iomem *pin_addr;
153 
154 	bit = 1 << gpio;
155 
156 	pin_addr = port->base + PINCTRL_IRQPOL(port);
157 	val = readl(pin_addr);
158 	edge = val & bit;
159 
160 	if (edge)
161 		writel(bit, pin_addr + MXS_CLR);
162 	else
163 		writel(bit, pin_addr + MXS_SET);
164 }
165 
166 /* MXS has one interrupt *per* gpio port */
167 static void mxs_gpio_irq_handler(struct irq_desc *desc)
168 {
169 	u32 irq_stat;
170 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
171 
172 	desc->irq_data.chip->irq_ack(&desc->irq_data);
173 
174 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
175 			readl(port->base + PINCTRL_IRQEN(port));
176 
177 	while (irq_stat != 0) {
178 		int irqoffset = fls(irq_stat) - 1;
179 		if (port->both_edges & (1 << irqoffset))
180 			mxs_flip_edge(port, irqoffset);
181 
182 		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
183 		irq_stat &= ~(1 << irqoffset);
184 	}
185 }
186 
187 /*
188  * Set interrupt number "irq" in the GPIO as a wake-up source.
189  * While system is running, all registered GPIO interrupts need to have
190  * wake-up enabled. When system is suspended, only selected GPIO interrupts
191  * need to have wake-up enabled.
192  * @param  irq          interrupt source number
193  * @param  enable       enable as wake-up if equal to non-zero
194  * @return       This function returns 0 on success.
195  */
196 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
197 {
198 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
199 	struct mxs_gpio_port *port = gc->private;
200 
201 	if (enable)
202 		enable_irq_wake(port->irq);
203 	else
204 		disable_irq_wake(port->irq);
205 
206 	return 0;
207 }
208 
209 static int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
210 {
211 	struct irq_chip_generic *gc;
212 	struct irq_chip_type *ct;
213 	int rv;
214 
215 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
216 					 port->base, handle_level_irq);
217 	if (!gc)
218 		return -ENOMEM;
219 
220 	gc->private = port;
221 
222 	ct = &gc->chip_types[0];
223 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
224 	ct->chip.irq_ack = irq_gc_ack_set_bit;
225 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
226 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
227 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
228 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
229 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
230 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
231 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
232 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
233 
234 	ct = &gc->chip_types[1];
235 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
236 	ct->chip.irq_ack = irq_gc_ack_set_bit;
237 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
238 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
239 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
240 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
241 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
242 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
243 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
244 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
245 	ct->handler = handle_level_irq;
246 
247 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
248 					 IRQ_GC_INIT_NESTED_LOCK,
249 					 IRQ_NOREQUEST, 0);
250 
251 	return rv;
252 }
253 
254 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
255 {
256 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
257 
258 	return irq_find_mapping(port->domain, offset);
259 }
260 
261 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
262 {
263 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
264 	u32 mask = 1 << offset;
265 	u32 dir;
266 
267 	dir = readl(port->base + PINCTRL_DOE(port));
268 	return !(dir & mask);
269 }
270 
271 static const struct platform_device_id mxs_gpio_ids[] = {
272 	{
273 		.name = "imx23-gpio",
274 		.driver_data = IMX23_GPIO,
275 	}, {
276 		.name = "imx28-gpio",
277 		.driver_data = IMX28_GPIO,
278 	}, {
279 		/* sentinel */
280 	}
281 };
282 MODULE_DEVICE_TABLE(platform, mxs_gpio_ids);
283 
284 static const struct of_device_id mxs_gpio_dt_ids[] = {
285 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
286 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
287 	{ /* sentinel */ }
288 };
289 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
290 
291 static int mxs_gpio_probe(struct platform_device *pdev)
292 {
293 	const struct of_device_id *of_id =
294 			of_match_device(mxs_gpio_dt_ids, &pdev->dev);
295 	struct device_node *np = pdev->dev.of_node;
296 	struct device_node *parent;
297 	static void __iomem *base;
298 	struct mxs_gpio_port *port;
299 	int irq_base;
300 	int err;
301 
302 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
303 	if (!port)
304 		return -ENOMEM;
305 
306 	port->id = of_alias_get_id(np, "gpio");
307 	if (port->id < 0)
308 		return port->id;
309 	port->devid = (enum mxs_gpio_id) of_id->data;
310 	port->dev = &pdev->dev;
311 	port->irq = platform_get_irq(pdev, 0);
312 	if (port->irq < 0)
313 		return port->irq;
314 
315 	/*
316 	 * map memory region only once, as all the gpio ports
317 	 * share the same one
318 	 */
319 	if (!base) {
320 		parent = of_get_parent(np);
321 		base = of_iomap(parent, 0);
322 		of_node_put(parent);
323 		if (!base)
324 			return -EADDRNOTAVAIL;
325 	}
326 	port->base = base;
327 
328 	/* initially disable the interrupts */
329 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
330 	writel(0, port->base + PINCTRL_IRQEN(port));
331 
332 	/* clear address has to be used to clear IRQSTAT bits */
333 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
334 
335 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
336 	if (irq_base < 0) {
337 		err = irq_base;
338 		goto out_iounmap;
339 	}
340 
341 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
342 					     &irq_domain_simple_ops, NULL);
343 	if (!port->domain) {
344 		err = -ENODEV;
345 		goto out_iounmap;
346 	}
347 
348 	/* gpio-mxs can be a generic irq chip */
349 	err = mxs_gpio_init_gc(port, irq_base);
350 	if (err < 0)
351 		goto out_irqdomain_remove;
352 
353 	/* setup one handler for each entry */
354 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
355 					 port);
356 
357 	err = bgpio_init(&port->gc, &pdev->dev, 4,
358 			 port->base + PINCTRL_DIN(port),
359 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
360 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
361 			 port->base + PINCTRL_DOE(port), NULL, 0);
362 	if (err)
363 		goto out_irqdomain_remove;
364 
365 	port->gc.to_irq = mxs_gpio_to_irq;
366 	port->gc.get_direction = mxs_gpio_get_direction;
367 	port->gc.base = port->id * 32;
368 
369 	err = gpiochip_add_data(&port->gc, port);
370 	if (err)
371 		goto out_irqdomain_remove;
372 
373 	return 0;
374 
375 out_irqdomain_remove:
376 	irq_domain_remove(port->domain);
377 out_iounmap:
378 	iounmap(port->base);
379 	return err;
380 }
381 
382 static struct platform_driver mxs_gpio_driver = {
383 	.driver		= {
384 		.name	= "gpio-mxs",
385 		.of_match_table = mxs_gpio_dt_ids,
386 		.suppress_bind_attrs = true,
387 	},
388 	.probe		= mxs_gpio_probe,
389 	.id_table	= mxs_gpio_ids,
390 };
391 
392 static int __init mxs_gpio_init(void)
393 {
394 	return platform_driver_register(&mxs_gpio_driver);
395 }
396 postcore_initcall(mxs_gpio_init);
397 
398 MODULE_AUTHOR("Freescale Semiconductor, "
399 	      "Daniel Mack <danielncaiaq.de>, "
400 	      "Juergen Beisert <kernel@pengutronix.de>");
401 MODULE_DESCRIPTION("Freescale MXS GPIO");
402 MODULE_LICENSE("GPL");
403