xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision 86e281fc) 
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/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/gpio/driver.h>
20 #include <linux/module.h>
21 
22 #define MXS_SET		0x4
23 #define MXS_CLR		0x8
24 
25 #define PINCTRL_DOUT(p)		((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
26 #define PINCTRL_DIN(p)		((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
27 #define PINCTRL_DOE(p)		((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
28 #define PINCTRL_PIN2IRQ(p)	((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
29 #define PINCTRL_IRQEN(p)	((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
30 #define PINCTRL_IRQLEV(p)	((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
31 #define PINCTRL_IRQPOL(p)	((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
32 #define PINCTRL_IRQSTAT(p)	((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
33 
34 #define GPIO_INT_FALL_EDGE	0x0
35 #define GPIO_INT_LOW_LEV	0x1
36 #define GPIO_INT_RISE_EDGE	0x2
37 #define GPIO_INT_HIGH_LEV	0x3
38 #define GPIO_INT_LEV_MASK	(1 << 0)
39 #define GPIO_INT_POL_MASK	(1 << 1)
40 
41 enum mxs_gpio_id {
42 	IMX23_GPIO,
43 	IMX28_GPIO,
44 };
45 
46 struct mxs_gpio_port {
47 	void __iomem *base;
48 	int id;
49 	int irq;
50 	struct irq_domain *domain;
51 	struct gpio_chip gc;
52 	struct device *dev;
53 	enum mxs_gpio_id devid;
54 	u32 both_edges;
55 };
56 
57 static inline int is_imx23_gpio(struct mxs_gpio_port *port)
58 {
59 	return port->devid == IMX23_GPIO;
60 }
61 
62 /* Note: This driver assumes 32 GPIOs are handled in one register */
63 
64 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
65 {
66 	u32 val;
67 	u32 pin_mask = 1 << d->hwirq;
68 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
69 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
70 	struct mxs_gpio_port *port = gc->private;
71 	void __iomem *pin_addr;
72 	int edge;
73 
74 	if (!(ct->type & type))
75 		if (irq_setup_alt_chip(d, type))
76 			return -EINVAL;
77 
78 	port->both_edges &= ~pin_mask;
79 	switch (type) {
80 	case IRQ_TYPE_EDGE_BOTH:
81 		val = readl(port->base + PINCTRL_DIN(port)) & pin_mask;
82 		if (val)
83 			edge = GPIO_INT_FALL_EDGE;
84 		else
85 			edge = GPIO_INT_RISE_EDGE;
86 		port->both_edges |= pin_mask;
87 		break;
88 	case IRQ_TYPE_EDGE_RISING:
89 		edge = GPIO_INT_RISE_EDGE;
90 		break;
91 	case IRQ_TYPE_EDGE_FALLING:
92 		edge = GPIO_INT_FALL_EDGE;
93 		break;
94 	case IRQ_TYPE_LEVEL_LOW:
95 		edge = GPIO_INT_LOW_LEV;
96 		break;
97 	case IRQ_TYPE_LEVEL_HIGH:
98 		edge = GPIO_INT_HIGH_LEV;
99 		break;
100 	default:
101 		return -EINVAL;
102 	}
103 
104 	/* set level or edge */
105 	pin_addr = port->base + PINCTRL_IRQLEV(port);
106 	if (edge & GPIO_INT_LEV_MASK) {
107 		writel(pin_mask, pin_addr + MXS_SET);
108 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
109 	} else {
110 		writel(pin_mask, pin_addr + MXS_CLR);
111 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
112 	}
113 
114 	/* set polarity */
115 	pin_addr = port->base + PINCTRL_IRQPOL(port);
116 	if (edge & GPIO_INT_POL_MASK)
117 		writel(pin_mask, pin_addr + MXS_SET);
118 	else
119 		writel(pin_mask, pin_addr + MXS_CLR);
120 
121 	writel(pin_mask, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
122 
123 	return 0;
124 }
125 
126 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
127 {
128 	u32 bit, val, edge;
129 	void __iomem *pin_addr;
130 
131 	bit = 1 << gpio;
132 
133 	pin_addr = port->base + PINCTRL_IRQPOL(port);
134 	val = readl(pin_addr);
135 	edge = val & bit;
136 
137 	if (edge)
138 		writel(bit, pin_addr + MXS_CLR);
139 	else
140 		writel(bit, pin_addr + MXS_SET);
141 }
142 
143 /* MXS has one interrupt *per* gpio port */
144 static void mxs_gpio_irq_handler(struct irq_desc *desc)
145 {
146 	u32 irq_stat;
147 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
148 
149 	desc->irq_data.chip->irq_ack(&desc->irq_data);
150 
151 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
152 			readl(port->base + PINCTRL_IRQEN(port));
153 
154 	while (irq_stat != 0) {
155 		int irqoffset = fls(irq_stat) - 1;
156 		if (port->both_edges & (1 << irqoffset))
157 			mxs_flip_edge(port, irqoffset);
158 
159 		generic_handle_domain_irq(port->domain, irqoffset);
160 		irq_stat &= ~(1 << irqoffset);
161 	}
162 }
163 
164 /*
165  * Set interrupt number "irq" in the GPIO as a wake-up source.
166  * While system is running, all registered GPIO interrupts need to have
167  * wake-up enabled. When system is suspended, only selected GPIO interrupts
168  * need to have wake-up enabled.
169  * @param  irq          interrupt source number
170  * @param  enable       enable as wake-up if equal to non-zero
171  * @return       This function returns 0 on success.
172  */
173 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
174 {
175 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
176 	struct mxs_gpio_port *port = gc->private;
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 int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
187 {
188 	struct irq_chip_generic *gc;
189 	struct irq_chip_type *ct;
190 	int rv;
191 
192 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
193 					 port->base, handle_level_irq);
194 	if (!gc)
195 		return -ENOMEM;
196 
197 	gc->private = port;
198 
199 	ct = &gc->chip_types[0];
200 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
201 	ct->chip.irq_ack = irq_gc_ack_set_bit;
202 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
203 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
204 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
205 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
206 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
207 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
208 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
209 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
210 
211 	ct = &gc->chip_types[1];
212 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
213 	ct->chip.irq_ack = irq_gc_ack_set_bit;
214 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
215 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
216 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
217 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
218 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
219 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
220 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
221 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
222 	ct->handler = handle_level_irq;
223 
224 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
225 					 IRQ_GC_INIT_NESTED_LOCK,
226 					 IRQ_NOREQUEST, 0);
227 
228 	return rv;
229 }
230 
231 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
232 {
233 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
234 
235 	return irq_find_mapping(port->domain, offset);
236 }
237 
238 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
239 {
240 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
241 	u32 mask = 1 << offset;
242 	u32 dir;
243 
244 	dir = readl(port->base + PINCTRL_DOE(port));
245 	if (dir & mask)
246 		return GPIO_LINE_DIRECTION_OUT;
247 
248 	return GPIO_LINE_DIRECTION_IN;
249 }
250 
251 static const struct of_device_id mxs_gpio_dt_ids[] = {
252 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
253 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
254 	{ /* sentinel */ }
255 };
256 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
257 
258 static int mxs_gpio_probe(struct platform_device *pdev)
259 {
260 	struct device_node *np = pdev->dev.of_node;
261 	struct device_node *parent;
262 	static void __iomem *base;
263 	struct mxs_gpio_port *port;
264 	int irq_base;
265 	int err;
266 
267 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
268 	if (!port)
269 		return -ENOMEM;
270 
271 	port->id = of_alias_get_id(np, "gpio");
272 	if (port->id < 0)
273 		return port->id;
274 	port->devid = (uintptr_t)of_device_get_match_data(&pdev->dev);
275 	port->dev = &pdev->dev;
276 	port->irq = platform_get_irq(pdev, 0);
277 	if (port->irq < 0)
278 		return port->irq;
279 
280 	/*
281 	 * map memory region only once, as all the gpio ports
282 	 * share the same one
283 	 */
284 	if (!base) {
285 		parent = of_get_parent(np);
286 		base = of_iomap(parent, 0);
287 		of_node_put(parent);
288 		if (!base)
289 			return -EADDRNOTAVAIL;
290 	}
291 	port->base = base;
292 
293 	/* initially disable the interrupts */
294 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
295 	writel(0, port->base + PINCTRL_IRQEN(port));
296 
297 	/* clear address has to be used to clear IRQSTAT bits */
298 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
299 
300 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
301 	if (irq_base < 0) {
302 		err = irq_base;
303 		goto out_iounmap;
304 	}
305 
306 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
307 					     &irq_domain_simple_ops, NULL);
308 	if (!port->domain) {
309 		err = -ENODEV;
310 		goto out_iounmap;
311 	}
312 
313 	/* gpio-mxs can be a generic irq chip */
314 	err = mxs_gpio_init_gc(port, irq_base);
315 	if (err < 0)
316 		goto out_irqdomain_remove;
317 
318 	/* setup one handler for each entry */
319 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
320 					 port);
321 
322 	err = bgpio_init(&port->gc, &pdev->dev, 4,
323 			 port->base + PINCTRL_DIN(port),
324 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
325 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
326 			 port->base + PINCTRL_DOE(port), NULL, 0);
327 	if (err)
328 		goto out_irqdomain_remove;
329 
330 	port->gc.to_irq = mxs_gpio_to_irq;
331 	port->gc.get_direction = mxs_gpio_get_direction;
332 	port->gc.base = port->id * 32;
333 
334 	err = gpiochip_add_data(&port->gc, port);
335 	if (err)
336 		goto out_irqdomain_remove;
337 
338 	return 0;
339 
340 out_irqdomain_remove:
341 	irq_domain_remove(port->domain);
342 out_iounmap:
343 	iounmap(port->base);
344 	return err;
345 }
346 
347 static struct platform_driver mxs_gpio_driver = {
348 	.driver		= {
349 		.name	= "gpio-mxs",
350 		.of_match_table = mxs_gpio_dt_ids,
351 		.suppress_bind_attrs = true,
352 	},
353 	.probe		= mxs_gpio_probe,
354 };
355 
356 static int __init mxs_gpio_init(void)
357 {
358 	return platform_driver_register(&mxs_gpio_driver);
359 }
360 postcore_initcall(mxs_gpio_init);
361 
362 MODULE_AUTHOR("Freescale Semiconductor, "
363 	      "Daniel Mack <danielncaiaq.de>, "
364 	      "Juergen Beisert <kernel@pengutronix.de>");
365 MODULE_DESCRIPTION("Freescale MXS GPIO");
366