xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision 2fa5ebe3) 
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // MXS GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
4 // Copyright 2008 Juergen Beisert, kernel@pengutronix.de
5 //
6 // Based on code from Freescale,
7 // Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
8 
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_device.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/gpio/driver.h>
21 #include <linux/module.h>
22 
23 #define MXS_SET		0x4
24 #define MXS_CLR		0x8
25 
26 #define PINCTRL_DOUT(p)		((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
27 #define PINCTRL_DIN(p)		((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
28 #define PINCTRL_DOE(p)		((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
29 #define PINCTRL_PIN2IRQ(p)	((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
30 #define PINCTRL_IRQEN(p)	((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
31 #define PINCTRL_IRQLEV(p)	((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
32 #define PINCTRL_IRQPOL(p)	((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
33 #define PINCTRL_IRQSTAT(p)	((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
34 
35 #define GPIO_INT_FALL_EDGE	0x0
36 #define GPIO_INT_LOW_LEV	0x1
37 #define GPIO_INT_RISE_EDGE	0x2
38 #define GPIO_INT_HIGH_LEV	0x3
39 #define GPIO_INT_LEV_MASK	(1 << 0)
40 #define GPIO_INT_POL_MASK	(1 << 1)
41 
42 enum mxs_gpio_id {
43 	IMX23_GPIO,
44 	IMX28_GPIO,
45 };
46 
47 struct mxs_gpio_port {
48 	void __iomem *base;
49 	int id;
50 	int irq;
51 	struct irq_domain *domain;
52 	struct gpio_chip gc;
53 	struct device *dev;
54 	enum mxs_gpio_id devid;
55 	u32 both_edges;
56 };
57 
58 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
59 {
60 	return port->devid == IMX23_GPIO;
61 }
62 
63 /* Note: This driver assumes 32 GPIOs are handled in one register */
64 
65 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
66 {
67 	u32 val;
68 	u32 pin_mask = 1 << d->hwirq;
69 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
70 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
71 	struct mxs_gpio_port *port = gc->private;
72 	void __iomem *pin_addr;
73 	int edge;
74 
75 	if (!(ct->type & type))
76 		if (irq_setup_alt_chip(d, type))
77 			return -EINVAL;
78 
79 	port->both_edges &= ~pin_mask;
80 	switch (type) {
81 	case IRQ_TYPE_EDGE_BOTH:
82 		val = readl(port->base + PINCTRL_DIN(port)) & pin_mask;
83 		if (val)
84 			edge = GPIO_INT_FALL_EDGE;
85 		else
86 			edge = GPIO_INT_RISE_EDGE;
87 		port->both_edges |= pin_mask;
88 		break;
89 	case IRQ_TYPE_EDGE_RISING:
90 		edge = GPIO_INT_RISE_EDGE;
91 		break;
92 	case IRQ_TYPE_EDGE_FALLING:
93 		edge = GPIO_INT_FALL_EDGE;
94 		break;
95 	case IRQ_TYPE_LEVEL_LOW:
96 		edge = GPIO_INT_LOW_LEV;
97 		break;
98 	case IRQ_TYPE_LEVEL_HIGH:
99 		edge = GPIO_INT_HIGH_LEV;
100 		break;
101 	default:
102 		return -EINVAL;
103 	}
104 
105 	/* set level or edge */
106 	pin_addr = port->base + PINCTRL_IRQLEV(port);
107 	if (edge & GPIO_INT_LEV_MASK) {
108 		writel(pin_mask, pin_addr + MXS_SET);
109 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
110 	} else {
111 		writel(pin_mask, pin_addr + MXS_CLR);
112 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
113 	}
114 
115 	/* set polarity */
116 	pin_addr = port->base + PINCTRL_IRQPOL(port);
117 	if (edge & GPIO_INT_POL_MASK)
118 		writel(pin_mask, pin_addr + MXS_SET);
119 	else
120 		writel(pin_mask, pin_addr + MXS_CLR);
121 
122 	writel(pin_mask, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
123 
124 	return 0;
125 }
126 
127 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
128 {
129 	u32 bit, val, edge;
130 	void __iomem *pin_addr;
131 
132 	bit = 1 << gpio;
133 
134 	pin_addr = port->base + PINCTRL_IRQPOL(port);
135 	val = readl(pin_addr);
136 	edge = val & bit;
137 
138 	if (edge)
139 		writel(bit, pin_addr + MXS_CLR);
140 	else
141 		writel(bit, pin_addr + MXS_SET);
142 }
143 
144 /* MXS has one interrupt *per* gpio port */
145 static void mxs_gpio_irq_handler(struct irq_desc *desc)
146 {
147 	u32 irq_stat;
148 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
149 
150 	desc->irq_data.chip->irq_ack(&desc->irq_data);
151 
152 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
153 			readl(port->base + PINCTRL_IRQEN(port));
154 
155 	while (irq_stat != 0) {
156 		int irqoffset = fls(irq_stat) - 1;
157 		if (port->both_edges & (1 << irqoffset))
158 			mxs_flip_edge(port, irqoffset);
159 
160 		generic_handle_domain_irq(port->domain, 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 irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
177 	struct mxs_gpio_port *port = gc->private;
178 
179 	if (enable)
180 		enable_irq_wake(port->irq);
181 	else
182 		disable_irq_wake(port->irq);
183 
184 	return 0;
185 }
186 
187 static int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
188 {
189 	struct irq_chip_generic *gc;
190 	struct irq_chip_type *ct;
191 	int rv;
192 
193 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
194 					 port->base, handle_level_irq);
195 	if (!gc)
196 		return -ENOMEM;
197 
198 	gc->private = port;
199 
200 	ct = &gc->chip_types[0];
201 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
202 	ct->chip.irq_ack = irq_gc_ack_set_bit;
203 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
204 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
205 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
206 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
207 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
208 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
209 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
210 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
211 
212 	ct = &gc->chip_types[1];
213 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
214 	ct->chip.irq_ack = irq_gc_ack_set_bit;
215 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
216 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
217 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
218 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
219 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
220 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
221 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
222 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
223 	ct->handler = handle_level_irq;
224 
225 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
226 					 IRQ_GC_INIT_NESTED_LOCK,
227 					 IRQ_NOREQUEST, 0);
228 
229 	return rv;
230 }
231 
232 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
233 {
234 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
235 
236 	return irq_find_mapping(port->domain, offset);
237 }
238 
239 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
240 {
241 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
242 	u32 mask = 1 << offset;
243 	u32 dir;
244 
245 	dir = readl(port->base + PINCTRL_DOE(port));
246 	if (dir & mask)
247 		return GPIO_LINE_DIRECTION_OUT;
248 
249 	return GPIO_LINE_DIRECTION_IN;
250 }
251 
252 static const struct of_device_id mxs_gpio_dt_ids[] = {
253 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
254 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
255 	{ /* sentinel */ }
256 };
257 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
258 
259 static int mxs_gpio_probe(struct platform_device *pdev)
260 {
261 	struct device_node *np = pdev->dev.of_node;
262 	struct device_node *parent;
263 	static void __iomem *base;
264 	struct mxs_gpio_port *port;
265 	int irq_base;
266 	int err;
267 
268 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
269 	if (!port)
270 		return -ENOMEM;
271 
272 	port->id = of_alias_get_id(np, "gpio");
273 	if (port->id < 0)
274 		return port->id;
275 	port->devid = (enum mxs_gpio_id)of_device_get_match_data(&pdev->dev);
276 	port->dev = &pdev->dev;
277 	port->irq = platform_get_irq(pdev, 0);
278 	if (port->irq < 0)
279 		return port->irq;
280 
281 	/*
282 	 * map memory region only once, as all the gpio ports
283 	 * share the same one
284 	 */
285 	if (!base) {
286 		parent = of_get_parent(np);
287 		base = of_iomap(parent, 0);
288 		of_node_put(parent);
289 		if (!base)
290 			return -EADDRNOTAVAIL;
291 	}
292 	port->base = base;
293 
294 	/* initially disable the interrupts */
295 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
296 	writel(0, port->base + PINCTRL_IRQEN(port));
297 
298 	/* clear address has to be used to clear IRQSTAT bits */
299 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
300 
301 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
302 	if (irq_base < 0) {
303 		err = irq_base;
304 		goto out_iounmap;
305 	}
306 
307 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
308 					     &irq_domain_simple_ops, NULL);
309 	if (!port->domain) {
310 		err = -ENODEV;
311 		goto out_iounmap;
312 	}
313 
314 	/* gpio-mxs can be a generic irq chip */
315 	err = mxs_gpio_init_gc(port, irq_base);
316 	if (err < 0)
317 		goto out_irqdomain_remove;
318 
319 	/* setup one handler for each entry */
320 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
321 					 port);
322 
323 	err = bgpio_init(&port->gc, &pdev->dev, 4,
324 			 port->base + PINCTRL_DIN(port),
325 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
326 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
327 			 port->base + PINCTRL_DOE(port), NULL, 0);
328 	if (err)
329 		goto out_irqdomain_remove;
330 
331 	port->gc.to_irq = mxs_gpio_to_irq;
332 	port->gc.get_direction = mxs_gpio_get_direction;
333 	port->gc.base = port->id * 32;
334 
335 	err = gpiochip_add_data(&port->gc, port);
336 	if (err)
337 		goto out_irqdomain_remove;
338 
339 	return 0;
340 
341 out_irqdomain_remove:
342 	irq_domain_remove(port->domain);
343 out_iounmap:
344 	iounmap(port->base);
345 	return err;
346 }
347 
348 static struct platform_driver mxs_gpio_driver = {
349 	.driver		= {
350 		.name	= "gpio-mxs",
351 		.of_match_table = mxs_gpio_dt_ids,
352 		.suppress_bind_attrs = true,
353 	},
354 	.probe		= mxs_gpio_probe,
355 };
356 
357 static int __init mxs_gpio_init(void)
358 {
359 	return platform_driver_register(&mxs_gpio_driver);
360 }
361 postcore_initcall(mxs_gpio_init);
362 
363 MODULE_AUTHOR("Freescale Semiconductor, "
364 	      "Daniel Mack <danielncaiaq.de>, "
365 	      "Juergen Beisert <kernel@pengutronix.de>");
366 MODULE_DESCRIPTION("Freescale MXS GPIO");
367 MODULE_LICENSE("GPL");
368