xref: /linux/drivers/gpio/gpio-mxs.c (revision 8c31b1635b91e48f867e010cd7bcd06393e5858a)
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/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/gpio.h>
28 #include <linux/platform_device.h>
29 #include <linux/slab.h>
30 #include <mach/mxs.h>
31 
32 #define MXS_SET		0x4
33 #define MXS_CLR		0x8
34 
35 #define PINCTRL_DOUT(n)		((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
36 #define PINCTRL_DIN(n)		((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
37 #define PINCTRL_DOE(n)		((cpu_is_mx23() ? 0x0700 : 0x0b00) + (n) * 0x10)
38 #define PINCTRL_PIN2IRQ(n)	((cpu_is_mx23() ? 0x0800 : 0x1000) + (n) * 0x10)
39 #define PINCTRL_IRQEN(n)	((cpu_is_mx23() ? 0x0900 : 0x1100) + (n) * 0x10)
40 #define PINCTRL_IRQLEV(n)	((cpu_is_mx23() ? 0x0a00 : 0x1200) + (n) * 0x10)
41 #define PINCTRL_IRQPOL(n)	((cpu_is_mx23() ? 0x0b00 : 0x1300) + (n) * 0x10)
42 #define PINCTRL_IRQSTAT(n)	((cpu_is_mx23() ? 0x0c00 : 0x1400) + (n) * 0x10)
43 
44 #define GPIO_INT_FALL_EDGE	0x0
45 #define GPIO_INT_LOW_LEV	0x1
46 #define GPIO_INT_RISE_EDGE	0x2
47 #define GPIO_INT_HIGH_LEV	0x3
48 #define GPIO_INT_LEV_MASK	(1 << 0)
49 #define GPIO_INT_POL_MASK	(1 << 1)
50 
51 struct mxs_gpio_port {
52 	void __iomem *base;
53 	int id;
54 	int irq;
55 	int irq_high;
56 	int virtual_irq_start;
57 	struct gpio_chip chip;
58 };
59 
60 /* Note: This driver assumes 32 GPIOs are handled in one register */
61 
62 static void clear_gpio_irqstatus(struct mxs_gpio_port *port, u32 index)
63 {
64 	writel(1 << index, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
65 }
66 
67 static void set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
68 				int enable)
69 {
70 	if (enable) {
71 		writel(1 << index,
72 			port->base + PINCTRL_IRQEN(port->id) + MXS_SET);
73 		writel(1 << index,
74 			port->base + PINCTRL_PIN2IRQ(port->id) + MXS_SET);
75 	} else {
76 		writel(1 << index,
77 			port->base + PINCTRL_IRQEN(port->id) + MXS_CLR);
78 	}
79 }
80 
81 static void mxs_gpio_ack_irq(struct irq_data *d)
82 {
83 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
84 	u32 gpio = irq_to_gpio(d->irq);
85 	clear_gpio_irqstatus(port, gpio & 0x1f);
86 }
87 
88 static void mxs_gpio_mask_irq(struct irq_data *d)
89 {
90 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
91 	u32 gpio = irq_to_gpio(d->irq);
92 	set_gpio_irqenable(port, gpio & 0x1f, 0);
93 }
94 
95 static void mxs_gpio_unmask_irq(struct irq_data *d)
96 {
97 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
98 	u32 gpio = irq_to_gpio(d->irq);
99 	set_gpio_irqenable(port, gpio & 0x1f, 1);
100 }
101 
102 static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset);
103 
104 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
105 {
106 	u32 gpio = irq_to_gpio(d->irq);
107 	u32 pin_mask = 1 << (gpio & 31);
108 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
109 	void __iomem *pin_addr;
110 	int edge;
111 
112 	switch (type) {
113 	case IRQ_TYPE_EDGE_RISING:
114 		edge = GPIO_INT_RISE_EDGE;
115 		break;
116 	case IRQ_TYPE_EDGE_FALLING:
117 		edge = GPIO_INT_FALL_EDGE;
118 		break;
119 	case IRQ_TYPE_LEVEL_LOW:
120 		edge = GPIO_INT_LOW_LEV;
121 		break;
122 	case IRQ_TYPE_LEVEL_HIGH:
123 		edge = GPIO_INT_HIGH_LEV;
124 		break;
125 	default:
126 		return -EINVAL;
127 	}
128 
129 	/* set level or edge */
130 	pin_addr = port->base + PINCTRL_IRQLEV(port->id);
131 	if (edge & GPIO_INT_LEV_MASK)
132 		writel(pin_mask, pin_addr + MXS_SET);
133 	else
134 		writel(pin_mask, pin_addr + MXS_CLR);
135 
136 	/* set polarity */
137 	pin_addr = port->base + PINCTRL_IRQPOL(port->id);
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 	clear_gpio_irqstatus(port, gpio & 0x1f);
144 
145 	return 0;
146 }
147 
148 /* MXS has one interrupt *per* gpio port */
149 static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
150 {
151 	u32 irq_stat;
152 	struct mxs_gpio_port *port = irq_get_handler_data(irq);
153 	u32 gpio_irq_no_base = port->virtual_irq_start;
154 
155 	desc->irq_data.chip->irq_ack(&desc->irq_data);
156 
157 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port->id)) &
158 			readl(port->base + PINCTRL_IRQEN(port->id));
159 
160 	while (irq_stat != 0) {
161 		int irqoffset = fls(irq_stat) - 1;
162 		generic_handle_irq(gpio_irq_no_base + irqoffset);
163 		irq_stat &= ~(1 << irqoffset);
164 	}
165 }
166 
167 /*
168  * Set interrupt number "irq" in the GPIO as a wake-up source.
169  * While system is running, all registered GPIO interrupts need to have
170  * wake-up enabled. When system is suspended, only selected GPIO interrupts
171  * need to have wake-up enabled.
172  * @param  irq          interrupt source number
173  * @param  enable       enable as wake-up if equal to non-zero
174  * @return       This function returns 0 on success.
175  */
176 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
177 {
178 	u32 gpio = irq_to_gpio(d->irq);
179 	u32 gpio_idx = gpio & 0x1f;
180 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
181 
182 	if (enable) {
183 		if (port->irq_high && (gpio_idx >= 16))
184 			enable_irq_wake(port->irq_high);
185 		else
186 			enable_irq_wake(port->irq);
187 	} else {
188 		if (port->irq_high && (gpio_idx >= 16))
189 			disable_irq_wake(port->irq_high);
190 		else
191 			disable_irq_wake(port->irq);
192 	}
193 
194 	return 0;
195 }
196 
197 static struct irq_chip gpio_irq_chip = {
198 	.name = "mxs gpio",
199 	.irq_ack = mxs_gpio_ack_irq,
200 	.irq_mask = mxs_gpio_mask_irq,
201 	.irq_unmask = mxs_gpio_unmask_irq,
202 	.irq_set_type = mxs_gpio_set_irq_type,
203 	.irq_set_wake = mxs_gpio_set_wake_irq,
204 };
205 
206 static void mxs_set_gpio_direction(struct gpio_chip *chip, unsigned offset,
207 				int dir)
208 {
209 	struct mxs_gpio_port *port =
210 		container_of(chip, struct mxs_gpio_port, chip);
211 	void __iomem *pin_addr = port->base + PINCTRL_DOE(port->id);
212 
213 	if (dir)
214 		writel(1 << offset, pin_addr + MXS_SET);
215 	else
216 		writel(1 << offset, pin_addr + MXS_CLR);
217 }
218 
219 static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
220 {
221 	struct mxs_gpio_port *port =
222 		container_of(chip, struct mxs_gpio_port, chip);
223 
224 	return (readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
225 }
226 
227 static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
228 {
229 	struct mxs_gpio_port *port =
230 		container_of(chip, struct mxs_gpio_port, chip);
231 	void __iomem *pin_addr = port->base + PINCTRL_DOUT(port->id);
232 
233 	if (value)
234 		writel(1 << offset, pin_addr + MXS_SET);
235 	else
236 		writel(1 << offset, pin_addr + MXS_CLR);
237 }
238 
239 static int mxs_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
240 {
241 	struct mxs_gpio_port *port =
242 		container_of(chip, struct mxs_gpio_port, chip);
243 
244 	return port->virtual_irq_start + offset;
245 }
246 
247 static int mxs_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
248 {
249 	mxs_set_gpio_direction(chip, offset, 0);
250 	return 0;
251 }
252 
253 static int mxs_gpio_direction_output(struct gpio_chip *chip,
254 				     unsigned offset, int value)
255 {
256 	mxs_gpio_set(chip, offset, value);
257 	mxs_set_gpio_direction(chip, offset, 1);
258 	return 0;
259 }
260 
261 static int __devinit mxs_gpio_probe(struct platform_device *pdev)
262 {
263 	static void __iomem *base;
264 	struct mxs_gpio_port *port;
265 	struct resource *iores = NULL;
266 	int err, i;
267 
268 	port = kzalloc(sizeof(struct mxs_gpio_port), GFP_KERNEL);
269 	if (!port)
270 		return -ENOMEM;
271 
272 	port->id = pdev->id;
273 	port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
274 
275 	/*
276 	 * map memory region only once, as all the gpio ports
277 	 * share the same one
278 	 */
279 	if (!base) {
280 		iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
281 		if (!iores) {
282 			err = -ENODEV;
283 			goto out_kfree;
284 		}
285 
286 		if (!request_mem_region(iores->start, resource_size(iores),
287 					pdev->name)) {
288 			err = -EBUSY;
289 			goto out_kfree;
290 		}
291 
292 		base = ioremap(iores->start, resource_size(iores));
293 		if (!base) {
294 			err = -ENOMEM;
295 			goto out_release_mem;
296 		}
297 	}
298 	port->base = base;
299 
300 	port->irq = platform_get_irq(pdev, 0);
301 	if (port->irq < 0) {
302 		err = -EINVAL;
303 		goto out_iounmap;
304 	}
305 
306 	/* disable the interrupt and clear the status */
307 	writel(0, port->base + PINCTRL_PIN2IRQ(port->id));
308 	writel(0, port->base + PINCTRL_IRQEN(port->id));
309 
310 	/* clear address has to be used to clear IRQSTAT bits */
311 	writel(~0U, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
312 
313 	for (i = port->virtual_irq_start;
314 		i < port->virtual_irq_start + 32; i++) {
315 		irq_set_chip_and_handler(i, &gpio_irq_chip,
316 					 handle_level_irq);
317 		set_irq_flags(i, IRQF_VALID);
318 		irq_set_chip_data(i, port);
319 	}
320 
321 	/* setup one handler for each entry */
322 	irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
323 	irq_set_handler_data(port->irq, port);
324 
325 	/* register gpio chip */
326 	port->chip.direction_input = mxs_gpio_direction_input;
327 	port->chip.direction_output = mxs_gpio_direction_output;
328 	port->chip.get = mxs_gpio_get;
329 	port->chip.set = mxs_gpio_set;
330 	port->chip.to_irq = mxs_gpio_to_irq;
331 	port->chip.base = port->id * 32;
332 	port->chip.ngpio = 32;
333 
334 	err = gpiochip_add(&port->chip);
335 	if (err)
336 		goto out_iounmap;
337 
338 	return 0;
339 
340 out_iounmap:
341 	if (iores)
342 		iounmap(port->base);
343 out_release_mem:
344 	if (iores)
345 		release_mem_region(iores->start, resource_size(iores));
346 out_kfree:
347 	kfree(port);
348 	dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
349 	return err;
350 }
351 
352 static struct platform_driver mxs_gpio_driver = {
353 	.driver		= {
354 		.name	= "gpio-mxs",
355 		.owner	= THIS_MODULE,
356 	},
357 	.probe		= mxs_gpio_probe,
358 };
359 
360 static int __init mxs_gpio_init(void)
361 {
362 	return platform_driver_register(&mxs_gpio_driver);
363 }
364 postcore_initcall(mxs_gpio_init);
365 
366 MODULE_AUTHOR("Freescale Semiconductor, "
367 	      "Daniel Mack <danielncaiaq.de>, "
368 	      "Juergen Beisert <kernel@pengutronix.de>");
369 MODULE_DESCRIPTION("Freescale MXS GPIO");
370 MODULE_LICENSE("GPL");
371