xref: /linux/drivers/gpio/gpio-mxs.c (revision 6161715e3f1adecae9e7c160930add4040fa10e9)
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 <linux/basic_mmio_gpio.h>
31 #include <mach/mxs.h>
32 
33 #define MXS_SET		0x4
34 #define MXS_CLR		0x8
35 
36 #define PINCTRL_DOUT(n)		((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
37 #define PINCTRL_DIN(n)		((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
38 #define PINCTRL_DOE(n)		((cpu_is_mx23() ? 0x0700 : 0x0b00) + (n) * 0x10)
39 #define PINCTRL_PIN2IRQ(n)	((cpu_is_mx23() ? 0x0800 : 0x1000) + (n) * 0x10)
40 #define PINCTRL_IRQEN(n)	((cpu_is_mx23() ? 0x0900 : 0x1100) + (n) * 0x10)
41 #define PINCTRL_IRQLEV(n)	((cpu_is_mx23() ? 0x0a00 : 0x1200) + (n) * 0x10)
42 #define PINCTRL_IRQPOL(n)	((cpu_is_mx23() ? 0x0b00 : 0x1300) + (n) * 0x10)
43 #define PINCTRL_IRQSTAT(n)	((cpu_is_mx23() ? 0x0c00 : 0x1400) + (n) * 0x10)
44 
45 #define GPIO_INT_FALL_EDGE	0x0
46 #define GPIO_INT_LOW_LEV	0x1
47 #define GPIO_INT_RISE_EDGE	0x2
48 #define GPIO_INT_HIGH_LEV	0x3
49 #define GPIO_INT_LEV_MASK	(1 << 0)
50 #define GPIO_INT_POL_MASK	(1 << 1)
51 
52 struct mxs_gpio_port {
53 	void __iomem *base;
54 	int id;
55 	int irq;
56 	int virtual_irq_start;
57 	struct bgpio_chip bgc;
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_set_irq_type(struct irq_data *d, unsigned int type)
103 {
104 	u32 gpio = irq_to_gpio(d->irq);
105 	u32 pin_mask = 1 << (gpio & 31);
106 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
107 	void __iomem *pin_addr;
108 	int edge;
109 
110 	switch (type) {
111 	case IRQ_TYPE_EDGE_RISING:
112 		edge = GPIO_INT_RISE_EDGE;
113 		break;
114 	case IRQ_TYPE_EDGE_FALLING:
115 		edge = GPIO_INT_FALL_EDGE;
116 		break;
117 	case IRQ_TYPE_LEVEL_LOW:
118 		edge = GPIO_INT_LOW_LEV;
119 		break;
120 	case IRQ_TYPE_LEVEL_HIGH:
121 		edge = GPIO_INT_HIGH_LEV;
122 		break;
123 	default:
124 		return -EINVAL;
125 	}
126 
127 	/* set level or edge */
128 	pin_addr = port->base + PINCTRL_IRQLEV(port->id);
129 	if (edge & GPIO_INT_LEV_MASK)
130 		writel(pin_mask, pin_addr + MXS_SET);
131 	else
132 		writel(pin_mask, pin_addr + MXS_CLR);
133 
134 	/* set polarity */
135 	pin_addr = port->base + PINCTRL_IRQPOL(port->id);
136 	if (edge & GPIO_INT_POL_MASK)
137 		writel(pin_mask, pin_addr + MXS_SET);
138 	else
139 		writel(pin_mask, pin_addr + MXS_CLR);
140 
141 	clear_gpio_irqstatus(port, gpio & 0x1f);
142 
143 	return 0;
144 }
145 
146 /* MXS has one interrupt *per* gpio port */
147 static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
148 {
149 	u32 irq_stat;
150 	struct mxs_gpio_port *port = irq_get_handler_data(irq);
151 	u32 gpio_irq_no_base = port->virtual_irq_start;
152 
153 	desc->irq_data.chip->irq_ack(&desc->irq_data);
154 
155 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port->id)) &
156 			readl(port->base + PINCTRL_IRQEN(port->id));
157 
158 	while (irq_stat != 0) {
159 		int irqoffset = fls(irq_stat) - 1;
160 		generic_handle_irq(gpio_irq_no_base + irqoffset);
161 		irq_stat &= ~(1 << irqoffset);
162 	}
163 }
164 
165 /*
166  * Set interrupt number "irq" in the GPIO as a wake-up source.
167  * While system is running, all registered GPIO interrupts need to have
168  * wake-up enabled. When system is suspended, only selected GPIO interrupts
169  * need to have wake-up enabled.
170  * @param  irq          interrupt source number
171  * @param  enable       enable as wake-up if equal to non-zero
172  * @return       This function returns 0 on success.
173  */
174 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
175 {
176 	struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
177 
178 	if (enable)
179 		enable_irq_wake(port->irq);
180 	else
181 		disable_irq_wake(port->irq);
182 
183 	return 0;
184 }
185 
186 static struct irq_chip gpio_irq_chip = {
187 	.name = "mxs gpio",
188 	.irq_ack = mxs_gpio_ack_irq,
189 	.irq_mask = mxs_gpio_mask_irq,
190 	.irq_unmask = mxs_gpio_unmask_irq,
191 	.irq_set_type = mxs_gpio_set_irq_type,
192 	.irq_set_wake = mxs_gpio_set_wake_irq,
193 };
194 
195 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
196 {
197 	struct bgpio_chip *bgc = to_bgpio_chip(gc);
198 	struct mxs_gpio_port *port =
199 		container_of(bgc, struct mxs_gpio_port, bgc);
200 
201 	return port->virtual_irq_start + offset;
202 }
203 
204 static int __devinit mxs_gpio_probe(struct platform_device *pdev)
205 {
206 	static void __iomem *base;
207 	struct mxs_gpio_port *port;
208 	struct resource *iores = NULL;
209 	int err, i;
210 
211 	port = kzalloc(sizeof(struct mxs_gpio_port), GFP_KERNEL);
212 	if (!port)
213 		return -ENOMEM;
214 
215 	port->id = pdev->id;
216 	port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
217 
218 	/*
219 	 * map memory region only once, as all the gpio ports
220 	 * share the same one
221 	 */
222 	if (!base) {
223 		iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
224 		if (!iores) {
225 			err = -ENODEV;
226 			goto out_kfree;
227 		}
228 
229 		if (!request_mem_region(iores->start, resource_size(iores),
230 					pdev->name)) {
231 			err = -EBUSY;
232 			goto out_kfree;
233 		}
234 
235 		base = ioremap(iores->start, resource_size(iores));
236 		if (!base) {
237 			err = -ENOMEM;
238 			goto out_release_mem;
239 		}
240 	}
241 	port->base = base;
242 
243 	port->irq = platform_get_irq(pdev, 0);
244 	if (port->irq < 0) {
245 		err = -EINVAL;
246 		goto out_iounmap;
247 	}
248 
249 	/* disable the interrupt and clear the status */
250 	writel(0, port->base + PINCTRL_PIN2IRQ(port->id));
251 	writel(0, port->base + PINCTRL_IRQEN(port->id));
252 
253 	/* clear address has to be used to clear IRQSTAT bits */
254 	writel(~0U, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
255 
256 	for (i = port->virtual_irq_start;
257 		i < port->virtual_irq_start + 32; i++) {
258 		irq_set_chip_and_handler(i, &gpio_irq_chip,
259 					 handle_level_irq);
260 		set_irq_flags(i, IRQF_VALID);
261 		irq_set_chip_data(i, port);
262 	}
263 
264 	/* setup one handler for each entry */
265 	irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
266 	irq_set_handler_data(port->irq, port);
267 
268 	err = bgpio_init(&port->bgc, &pdev->dev, 4,
269 			 port->base + PINCTRL_DIN(port->id),
270 			 port->base + PINCTRL_DOUT(port->id), NULL,
271 			 port->base + PINCTRL_DOE(port->id), NULL, false);
272 	if (err)
273 		goto out_iounmap;
274 
275 	port->bgc.gc.to_irq = mxs_gpio_to_irq;
276 	port->bgc.gc.base = port->id * 32;
277 
278 	err = gpiochip_add(&port->bgc.gc);
279 	if (err)
280 		goto out_bgpio_remove;
281 
282 	return 0;
283 
284 out_bgpio_remove:
285 	bgpio_remove(&port->bgc);
286 out_iounmap:
287 	if (iores)
288 		iounmap(port->base);
289 out_release_mem:
290 	if (iores)
291 		release_mem_region(iores->start, resource_size(iores));
292 out_kfree:
293 	kfree(port);
294 	dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
295 	return err;
296 }
297 
298 static struct platform_driver mxs_gpio_driver = {
299 	.driver		= {
300 		.name	= "gpio-mxs",
301 		.owner	= THIS_MODULE,
302 	},
303 	.probe		= mxs_gpio_probe,
304 };
305 
306 static int __init mxs_gpio_init(void)
307 {
308 	return platform_driver_register(&mxs_gpio_driver);
309 }
310 postcore_initcall(mxs_gpio_init);
311 
312 MODULE_AUTHOR("Freescale Semiconductor, "
313 	      "Daniel Mack <danielncaiaq.de>, "
314 	      "Juergen Beisert <kernel@pengutronix.de>");
315 MODULE_DESCRIPTION("Freescale MXS GPIO");
316 MODULE_LICENSE("GPL");
317