xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision ba61bb17) 
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // MXC 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 /* FIXME: for gpio_get_value(), replace this by direct register read */
22 #include <linux/gpio.h>
23 #include <linux/module.h>
24 
25 #define MXS_SET		0x4
26 #define MXS_CLR		0x8
27 
28 #define PINCTRL_DOUT(p)		((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
29 #define PINCTRL_DIN(p)		((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
30 #define PINCTRL_DOE(p)		((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
31 #define PINCTRL_PIN2IRQ(p)	((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
32 #define PINCTRL_IRQEN(p)	((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
33 #define PINCTRL_IRQLEV(p)	((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
34 #define PINCTRL_IRQPOL(p)	((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
35 #define PINCTRL_IRQSTAT(p)	((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
36 
37 #define GPIO_INT_FALL_EDGE	0x0
38 #define GPIO_INT_LOW_LEV	0x1
39 #define GPIO_INT_RISE_EDGE	0x2
40 #define GPIO_INT_HIGH_LEV	0x3
41 #define GPIO_INT_LEV_MASK	(1 << 0)
42 #define GPIO_INT_POL_MASK	(1 << 1)
43 
44 enum mxs_gpio_id {
45 	IMX23_GPIO,
46 	IMX28_GPIO,
47 };
48 
49 struct mxs_gpio_port {
50 	void __iomem *base;
51 	int id;
52 	int irq;
53 	struct irq_domain *domain;
54 	struct gpio_chip gc;
55 	struct device *dev;
56 	enum mxs_gpio_id devid;
57 	u32 both_edges;
58 };
59 
60 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
61 {
62 	return port->devid == IMX23_GPIO;
63 }
64 
65 static inline int is_imx28_gpio(struct mxs_gpio_port *port)
66 {
67 	return port->devid == IMX28_GPIO;
68 }
69 
70 /* Note: This driver assumes 32 GPIOs are handled in one register */
71 
72 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
73 {
74 	u32 val;
75 	u32 pin_mask = 1 << d->hwirq;
76 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
77 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
78 	struct mxs_gpio_port *port = gc->private;
79 	void __iomem *pin_addr;
80 	int edge;
81 
82 	if (!(ct->type & type))
83 		if (irq_setup_alt_chip(d, type))
84 			return -EINVAL;
85 
86 	port->both_edges &= ~pin_mask;
87 	switch (type) {
88 	case IRQ_TYPE_EDGE_BOTH:
89 		val = gpio_get_value(port->gc.base + d->hwirq);
90 		if (val)
91 			edge = GPIO_INT_FALL_EDGE;
92 		else
93 			edge = GPIO_INT_RISE_EDGE;
94 		port->both_edges |= pin_mask;
95 		break;
96 	case IRQ_TYPE_EDGE_RISING:
97 		edge = GPIO_INT_RISE_EDGE;
98 		break;
99 	case IRQ_TYPE_EDGE_FALLING:
100 		edge = GPIO_INT_FALL_EDGE;
101 		break;
102 	case IRQ_TYPE_LEVEL_LOW:
103 		edge = GPIO_INT_LOW_LEV;
104 		break;
105 	case IRQ_TYPE_LEVEL_HIGH:
106 		edge = GPIO_INT_HIGH_LEV;
107 		break;
108 	default:
109 		return -EINVAL;
110 	}
111 
112 	/* set level or edge */
113 	pin_addr = port->base + PINCTRL_IRQLEV(port);
114 	if (edge & GPIO_INT_LEV_MASK) {
115 		writel(pin_mask, pin_addr + MXS_SET);
116 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
117 	} else {
118 		writel(pin_mask, pin_addr + MXS_CLR);
119 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
120 	}
121 
122 	/* set polarity */
123 	pin_addr = port->base + PINCTRL_IRQPOL(port);
124 	if (edge & GPIO_INT_POL_MASK)
125 		writel(pin_mask, pin_addr + MXS_SET);
126 	else
127 		writel(pin_mask, pin_addr + MXS_CLR);
128 
129 	writel(pin_mask,
130 	       port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
131 
132 	return 0;
133 }
134 
135 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
136 {
137 	u32 bit, val, edge;
138 	void __iomem *pin_addr;
139 
140 	bit = 1 << gpio;
141 
142 	pin_addr = port->base + PINCTRL_IRQPOL(port);
143 	val = readl(pin_addr);
144 	edge = val & bit;
145 
146 	if (edge)
147 		writel(bit, pin_addr + MXS_CLR);
148 	else
149 		writel(bit, pin_addr + MXS_SET);
150 }
151 
152 /* MXS has one interrupt *per* gpio port */
153 static void mxs_gpio_irq_handler(struct irq_desc *desc)
154 {
155 	u32 irq_stat;
156 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
157 
158 	desc->irq_data.chip->irq_ack(&desc->irq_data);
159 
160 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
161 			readl(port->base + PINCTRL_IRQEN(port));
162 
163 	while (irq_stat != 0) {
164 		int irqoffset = fls(irq_stat) - 1;
165 		if (port->both_edges & (1 << irqoffset))
166 			mxs_flip_edge(port, irqoffset);
167 
168 		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
169 		irq_stat &= ~(1 << irqoffset);
170 	}
171 }
172 
173 /*
174  * Set interrupt number "irq" in the GPIO as a wake-up source.
175  * While system is running, all registered GPIO interrupts need to have
176  * wake-up enabled. When system is suspended, only selected GPIO interrupts
177  * need to have wake-up enabled.
178  * @param  irq          interrupt source number
179  * @param  enable       enable as wake-up if equal to non-zero
180  * @return       This function returns 0 on success.
181  */
182 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
183 {
184 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
185 	struct mxs_gpio_port *port = gc->private;
186 
187 	if (enable)
188 		enable_irq_wake(port->irq);
189 	else
190 		disable_irq_wake(port->irq);
191 
192 	return 0;
193 }
194 
195 static int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
196 {
197 	struct irq_chip_generic *gc;
198 	struct irq_chip_type *ct;
199 	int rv;
200 
201 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
202 					 port->base, handle_level_irq);
203 	if (!gc)
204 		return -ENOMEM;
205 
206 	gc->private = port;
207 
208 	ct = &gc->chip_types[0];
209 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
210 	ct->chip.irq_ack = irq_gc_ack_set_bit;
211 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
212 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
213 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
214 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
215 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
216 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
217 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
218 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
219 
220 	ct = &gc->chip_types[1];
221 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
222 	ct->chip.irq_ack = irq_gc_ack_set_bit;
223 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
224 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
225 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
226 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
227 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
228 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
229 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
230 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
231 	ct->handler = handle_level_irq;
232 
233 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
234 					 IRQ_GC_INIT_NESTED_LOCK,
235 					 IRQ_NOREQUEST, 0);
236 
237 	return rv;
238 }
239 
240 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
241 {
242 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
243 
244 	return irq_find_mapping(port->domain, offset);
245 }
246 
247 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
248 {
249 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
250 	u32 mask = 1 << offset;
251 	u32 dir;
252 
253 	dir = readl(port->base + PINCTRL_DOE(port));
254 	return !(dir & mask);
255 }
256 
257 static const struct platform_device_id mxs_gpio_ids[] = {
258 	{
259 		.name = "imx23-gpio",
260 		.driver_data = IMX23_GPIO,
261 	}, {
262 		.name = "imx28-gpio",
263 		.driver_data = IMX28_GPIO,
264 	}, {
265 		/* sentinel */
266 	}
267 };
268 MODULE_DEVICE_TABLE(platform, mxs_gpio_ids);
269 
270 static const struct of_device_id mxs_gpio_dt_ids[] = {
271 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
272 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
273 	{ /* sentinel */ }
274 };
275 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
276 
277 static int mxs_gpio_probe(struct platform_device *pdev)
278 {
279 	struct device_node *np = pdev->dev.of_node;
280 	struct device_node *parent;
281 	static void __iomem *base;
282 	struct mxs_gpio_port *port;
283 	int irq_base;
284 	int err;
285 
286 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
287 	if (!port)
288 		return -ENOMEM;
289 
290 	port->id = of_alias_get_id(np, "gpio");
291 	if (port->id < 0)
292 		return port->id;
293 	port->devid = (enum mxs_gpio_id)of_device_get_match_data(&pdev->dev);
294 	port->dev = &pdev->dev;
295 	port->irq = platform_get_irq(pdev, 0);
296 	if (port->irq < 0)
297 		return port->irq;
298 
299 	/*
300 	 * map memory region only once, as all the gpio ports
301 	 * share the same one
302 	 */
303 	if (!base) {
304 		parent = of_get_parent(np);
305 		base = of_iomap(parent, 0);
306 		of_node_put(parent);
307 		if (!base)
308 			return -EADDRNOTAVAIL;
309 	}
310 	port->base = base;
311 
312 	/* initially disable the interrupts */
313 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
314 	writel(0, port->base + PINCTRL_IRQEN(port));
315 
316 	/* clear address has to be used to clear IRQSTAT bits */
317 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
318 
319 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
320 	if (irq_base < 0) {
321 		err = irq_base;
322 		goto out_iounmap;
323 	}
324 
325 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
326 					     &irq_domain_simple_ops, NULL);
327 	if (!port->domain) {
328 		err = -ENODEV;
329 		goto out_iounmap;
330 	}
331 
332 	/* gpio-mxs can be a generic irq chip */
333 	err = mxs_gpio_init_gc(port, irq_base);
334 	if (err < 0)
335 		goto out_irqdomain_remove;
336 
337 	/* setup one handler for each entry */
338 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
339 					 port);
340 
341 	err = bgpio_init(&port->gc, &pdev->dev, 4,
342 			 port->base + PINCTRL_DIN(port),
343 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
344 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
345 			 port->base + PINCTRL_DOE(port), NULL, 0);
346 	if (err)
347 		goto out_irqdomain_remove;
348 
349 	port->gc.to_irq = mxs_gpio_to_irq;
350 	port->gc.get_direction = mxs_gpio_get_direction;
351 	port->gc.base = port->id * 32;
352 
353 	err = gpiochip_add_data(&port->gc, port);
354 	if (err)
355 		goto out_irqdomain_remove;
356 
357 	return 0;
358 
359 out_irqdomain_remove:
360 	irq_domain_remove(port->domain);
361 out_iounmap:
362 	iounmap(port->base);
363 	return err;
364 }
365 
366 static struct platform_driver mxs_gpio_driver = {
367 	.driver		= {
368 		.name	= "gpio-mxs",
369 		.of_match_table = mxs_gpio_dt_ids,
370 		.suppress_bind_attrs = true,
371 	},
372 	.probe		= mxs_gpio_probe,
373 	.id_table	= mxs_gpio_ids,
374 };
375 
376 static int __init mxs_gpio_init(void)
377 {
378 	return platform_driver_register(&mxs_gpio_driver);
379 }
380 postcore_initcall(mxs_gpio_init);
381 
382 MODULE_AUTHOR("Freescale Semiconductor, "
383 	      "Daniel Mack <danielncaiaq.de>, "
384 	      "Juergen Beisert <kernel@pengutronix.de>");
385 MODULE_DESCRIPTION("Freescale MXS GPIO");
386 MODULE_LICENSE("GPL");
387