xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision 95e9fd10)
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/of.h>
29 #include <linux/of_address.h>
30 #include <linux/of_device.h>
31 #include <linux/platform_device.h>
32 #include <linux/slab.h>
33 #include <linux/basic_mmio_gpio.h>
34 #include <linux/module.h>
35 
36 #define MXS_SET		0x4
37 #define MXS_CLR		0x8
38 
39 #define PINCTRL_DOUT(p)		((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
40 #define PINCTRL_DIN(p)		((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
41 #define PINCTRL_DOE(p)		((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
42 #define PINCTRL_PIN2IRQ(p)	((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
43 #define PINCTRL_IRQEN(p)	((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
44 #define PINCTRL_IRQLEV(p)	((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
45 #define PINCTRL_IRQPOL(p)	((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
46 #define PINCTRL_IRQSTAT(p)	((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
47 
48 #define GPIO_INT_FALL_EDGE	0x0
49 #define GPIO_INT_LOW_LEV	0x1
50 #define GPIO_INT_RISE_EDGE	0x2
51 #define GPIO_INT_HIGH_LEV	0x3
52 #define GPIO_INT_LEV_MASK	(1 << 0)
53 #define GPIO_INT_POL_MASK	(1 << 1)
54 
55 #define irq_to_gpio(irq)	((irq) - MXS_GPIO_IRQ_START)
56 
57 enum mxs_gpio_id {
58 	IMX23_GPIO,
59 	IMX28_GPIO,
60 };
61 
62 struct mxs_gpio_port {
63 	void __iomem *base;
64 	int id;
65 	int irq;
66 	int virtual_irq_start;
67 	struct bgpio_chip bgc;
68 	enum mxs_gpio_id devid;
69 };
70 
71 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
72 {
73 	return port->devid == IMX23_GPIO;
74 }
75 
76 static inline int is_imx28_gpio(struct mxs_gpio_port *port)
77 {
78 	return port->devid == IMX28_GPIO;
79 }
80 
81 /* Note: This driver assumes 32 GPIOs are handled in one register */
82 
83 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
84 {
85 	u32 gpio = irq_to_gpio(d->irq);
86 	u32 pin_mask = 1 << (gpio & 31);
87 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
88 	struct mxs_gpio_port *port = gc->private;
89 	void __iomem *pin_addr;
90 	int edge;
91 
92 	switch (type) {
93 	case IRQ_TYPE_EDGE_RISING:
94 		edge = GPIO_INT_RISE_EDGE;
95 		break;
96 	case IRQ_TYPE_EDGE_FALLING:
97 		edge = GPIO_INT_FALL_EDGE;
98 		break;
99 	case IRQ_TYPE_LEVEL_LOW:
100 		edge = GPIO_INT_LOW_LEV;
101 		break;
102 	case IRQ_TYPE_LEVEL_HIGH:
103 		edge = GPIO_INT_HIGH_LEV;
104 		break;
105 	default:
106 		return -EINVAL;
107 	}
108 
109 	/* set level or edge */
110 	pin_addr = port->base + PINCTRL_IRQLEV(port);
111 	if (edge & GPIO_INT_LEV_MASK)
112 		writel(pin_mask, pin_addr + MXS_SET);
113 	else
114 		writel(pin_mask, pin_addr + MXS_CLR);
115 
116 	/* set polarity */
117 	pin_addr = port->base + PINCTRL_IRQPOL(port);
118 	if (edge & GPIO_INT_POL_MASK)
119 		writel(pin_mask, pin_addr + MXS_SET);
120 	else
121 		writel(pin_mask, pin_addr + MXS_CLR);
122 
123 	writel(1 << (gpio & 0x1f),
124 	       port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
125 
126 	return 0;
127 }
128 
129 /* MXS has one interrupt *per* gpio port */
130 static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
131 {
132 	u32 irq_stat;
133 	struct mxs_gpio_port *port = irq_get_handler_data(irq);
134 	u32 gpio_irq_no_base = port->virtual_irq_start;
135 
136 	desc->irq_data.chip->irq_ack(&desc->irq_data);
137 
138 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
139 			readl(port->base + PINCTRL_IRQEN(port));
140 
141 	while (irq_stat != 0) {
142 		int irqoffset = fls(irq_stat) - 1;
143 		generic_handle_irq(gpio_irq_no_base + irqoffset);
144 		irq_stat &= ~(1 << irqoffset);
145 	}
146 }
147 
148 /*
149  * Set interrupt number "irq" in the GPIO as a wake-up source.
150  * While system is running, all registered GPIO interrupts need to have
151  * wake-up enabled. When system is suspended, only selected GPIO interrupts
152  * need to have wake-up enabled.
153  * @param  irq          interrupt source number
154  * @param  enable       enable as wake-up if equal to non-zero
155  * @return       This function returns 0 on success.
156  */
157 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
158 {
159 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
160 	struct mxs_gpio_port *port = gc->private;
161 
162 	if (enable)
163 		enable_irq_wake(port->irq);
164 	else
165 		disable_irq_wake(port->irq);
166 
167 	return 0;
168 }
169 
170 static void __init mxs_gpio_init_gc(struct mxs_gpio_port *port)
171 {
172 	struct irq_chip_generic *gc;
173 	struct irq_chip_type *ct;
174 
175 	gc = irq_alloc_generic_chip("gpio-mxs", 1, port->virtual_irq_start,
176 				    port->base, handle_level_irq);
177 	gc->private = port;
178 
179 	ct = gc->chip_types;
180 	ct->chip.irq_ack = irq_gc_ack_set_bit;
181 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
182 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
183 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
184 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
185 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
186 	ct->regs.mask = PINCTRL_IRQEN(port);
187 
188 	irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
189 }
190 
191 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
192 {
193 	struct bgpio_chip *bgc = to_bgpio_chip(gc);
194 	struct mxs_gpio_port *port =
195 		container_of(bgc, struct mxs_gpio_port, bgc);
196 
197 	return port->virtual_irq_start + offset;
198 }
199 
200 static struct platform_device_id mxs_gpio_ids[] = {
201 	{
202 		.name = "imx23-gpio",
203 		.driver_data = IMX23_GPIO,
204 	}, {
205 		.name = "imx28-gpio",
206 		.driver_data = IMX28_GPIO,
207 	}, {
208 		/* sentinel */
209 	}
210 };
211 MODULE_DEVICE_TABLE(platform, mxs_gpio_ids);
212 
213 static const struct of_device_id mxs_gpio_dt_ids[] = {
214 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
215 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
216 	{ /* sentinel */ }
217 };
218 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
219 
220 static int __devinit mxs_gpio_probe(struct platform_device *pdev)
221 {
222 	const struct of_device_id *of_id =
223 			of_match_device(mxs_gpio_dt_ids, &pdev->dev);
224 	struct device_node *np = pdev->dev.of_node;
225 	struct device_node *parent;
226 	static void __iomem *base;
227 	struct mxs_gpio_port *port;
228 	struct resource *iores = NULL;
229 	int err;
230 
231 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
232 	if (!port)
233 		return -ENOMEM;
234 
235 	if (np) {
236 		port->id = of_alias_get_id(np, "gpio");
237 		if (port->id < 0)
238 			return port->id;
239 		port->devid = (enum mxs_gpio_id) of_id->data;
240 	} else {
241 		port->id = pdev->id;
242 		port->devid = pdev->id_entry->driver_data;
243 	}
244 	port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
245 
246 	port->irq = platform_get_irq(pdev, 0);
247 	if (port->irq < 0)
248 		return port->irq;
249 
250 	/*
251 	 * map memory region only once, as all the gpio ports
252 	 * share the same one
253 	 */
254 	if (!base) {
255 		if (np) {
256 			parent = of_get_parent(np);
257 			base = of_iomap(parent, 0);
258 			of_node_put(parent);
259 		} else {
260 			iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
261 			base = devm_request_and_ioremap(&pdev->dev, iores);
262 		}
263 		if (!base)
264 			return -EADDRNOTAVAIL;
265 	}
266 	port->base = base;
267 
268 	/*
269 	 * select the pin interrupt functionality but initially
270 	 * disable the interrupts
271 	 */
272 	writel(~0U, port->base + PINCTRL_PIN2IRQ(port));
273 	writel(0, port->base + PINCTRL_IRQEN(port));
274 
275 	/* clear address has to be used to clear IRQSTAT bits */
276 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
277 
278 	/* gpio-mxs can be a generic irq chip */
279 	mxs_gpio_init_gc(port);
280 
281 	/* setup one handler for each entry */
282 	irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
283 	irq_set_handler_data(port->irq, port);
284 
285 	err = bgpio_init(&port->bgc, &pdev->dev, 4,
286 			 port->base + PINCTRL_DIN(port),
287 			 port->base + PINCTRL_DOUT(port), NULL,
288 			 port->base + PINCTRL_DOE(port), NULL, 0);
289 	if (err)
290 		return err;
291 
292 	port->bgc.gc.to_irq = mxs_gpio_to_irq;
293 	port->bgc.gc.base = port->id * 32;
294 
295 	err = gpiochip_add(&port->bgc.gc);
296 	if (err) {
297 		bgpio_remove(&port->bgc);
298 		return err;
299 	}
300 
301 	return 0;
302 }
303 
304 static struct platform_driver mxs_gpio_driver = {
305 	.driver		= {
306 		.name	= "gpio-mxs",
307 		.owner	= THIS_MODULE,
308 		.of_match_table = mxs_gpio_dt_ids,
309 	},
310 	.probe		= mxs_gpio_probe,
311 	.id_table	= mxs_gpio_ids,
312 };
313 
314 static int __init mxs_gpio_init(void)
315 {
316 	return platform_driver_register(&mxs_gpio_driver);
317 }
318 postcore_initcall(mxs_gpio_init);
319 
320 MODULE_AUTHOR("Freescale Semiconductor, "
321 	      "Daniel Mack <danielncaiaq.de>, "
322 	      "Juergen Beisert <kernel@pengutronix.de>");
323 MODULE_DESCRIPTION("Freescale MXS GPIO");
324 MODULE_LICENSE("GPL");
325