xref: /openbmc/linux/drivers/gpio/gpio-mxs.c (revision 6abeae2a) 
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 #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 static inline int is_imx28_gpio(struct mxs_gpio_port *port)
64 {
65 	return port->devid == IMX28_GPIO;
66 }
67 
68 /* Note: This driver assumes 32 GPIOs are handled in one register */
69 
70 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
71 {
72 	u32 val;
73 	u32 pin_mask = 1 << d->hwirq;
74 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
75 	struct irq_chip_type *ct = irq_data_get_chip_type(d);
76 	struct mxs_gpio_port *port = gc->private;
77 	void __iomem *pin_addr;
78 	int edge;
79 
80 	if (!(ct->type & type))
81 		if (irq_setup_alt_chip(d, type))
82 			return -EINVAL;
83 
84 	port->both_edges &= ~pin_mask;
85 	switch (type) {
86 	case IRQ_TYPE_EDGE_BOTH:
87 		val = readl(port->base + PINCTRL_DIN(port)) & pin_mask;
88 		if (val)
89 			edge = GPIO_INT_FALL_EDGE;
90 		else
91 			edge = GPIO_INT_RISE_EDGE;
92 		port->both_edges |= pin_mask;
93 		break;
94 	case IRQ_TYPE_EDGE_RISING:
95 		edge = GPIO_INT_RISE_EDGE;
96 		break;
97 	case IRQ_TYPE_EDGE_FALLING:
98 		edge = GPIO_INT_FALL_EDGE;
99 		break;
100 	case IRQ_TYPE_LEVEL_LOW:
101 		edge = GPIO_INT_LOW_LEV;
102 		break;
103 	case IRQ_TYPE_LEVEL_HIGH:
104 		edge = GPIO_INT_HIGH_LEV;
105 		break;
106 	default:
107 		return -EINVAL;
108 	}
109 
110 	/* set level or edge */
111 	pin_addr = port->base + PINCTRL_IRQLEV(port);
112 	if (edge & GPIO_INT_LEV_MASK) {
113 		writel(pin_mask, pin_addr + MXS_SET);
114 		writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
115 	} else {
116 		writel(pin_mask, pin_addr + MXS_CLR);
117 		writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
118 	}
119 
120 	/* set polarity */
121 	pin_addr = port->base + PINCTRL_IRQPOL(port);
122 	if (edge & GPIO_INT_POL_MASK)
123 		writel(pin_mask, pin_addr + MXS_SET);
124 	else
125 		writel(pin_mask, pin_addr + MXS_CLR);
126 
127 	writel(pin_mask, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
128 
129 	return 0;
130 }
131 
132 static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
133 {
134 	u32 bit, val, edge;
135 	void __iomem *pin_addr;
136 
137 	bit = 1 << gpio;
138 
139 	pin_addr = port->base + PINCTRL_IRQPOL(port);
140 	val = readl(pin_addr);
141 	edge = val & bit;
142 
143 	if (edge)
144 		writel(bit, pin_addr + MXS_CLR);
145 	else
146 		writel(bit, pin_addr + MXS_SET);
147 }
148 
149 /* MXS has one interrupt *per* gpio port */
150 static void mxs_gpio_irq_handler(struct irq_desc *desc)
151 {
152 	u32 irq_stat;
153 	struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
154 
155 	desc->irq_data.chip->irq_ack(&desc->irq_data);
156 
157 	irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
158 			readl(port->base + PINCTRL_IRQEN(port));
159 
160 	while (irq_stat != 0) {
161 		int irqoffset = fls(irq_stat) - 1;
162 		if (port->both_edges & (1 << irqoffset))
163 			mxs_flip_edge(port, irqoffset);
164 
165 		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
166 		irq_stat &= ~(1 << irqoffset);
167 	}
168 }
169 
170 /*
171  * Set interrupt number "irq" in the GPIO as a wake-up source.
172  * While system is running, all registered GPIO interrupts need to have
173  * wake-up enabled. When system is suspended, only selected GPIO interrupts
174  * need to have wake-up enabled.
175  * @param  irq          interrupt source number
176  * @param  enable       enable as wake-up if equal to non-zero
177  * @return       This function returns 0 on success.
178  */
179 static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
180 {
181 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
182 	struct mxs_gpio_port *port = gc->private;
183 
184 	if (enable)
185 		enable_irq_wake(port->irq);
186 	else
187 		disable_irq_wake(port->irq);
188 
189 	return 0;
190 }
191 
192 static int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
193 {
194 	struct irq_chip_generic *gc;
195 	struct irq_chip_type *ct;
196 	int rv;
197 
198 	gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
199 					 port->base, handle_level_irq);
200 	if (!gc)
201 		return -ENOMEM;
202 
203 	gc->private = port;
204 
205 	ct = &gc->chip_types[0];
206 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
207 	ct->chip.irq_ack = irq_gc_ack_set_bit;
208 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
209 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
210 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
211 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
212 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
213 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
214 	ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
215 	ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
216 
217 	ct = &gc->chip_types[1];
218 	ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
219 	ct->chip.irq_ack = irq_gc_ack_set_bit;
220 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
221 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
222 	ct->chip.irq_set_type = mxs_gpio_set_irq_type;
223 	ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
224 	ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
225 	ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
226 	ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
227 	ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
228 	ct->handler = handle_level_irq;
229 
230 	rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
231 					 IRQ_GC_INIT_NESTED_LOCK,
232 					 IRQ_NOREQUEST, 0);
233 
234 	return rv;
235 }
236 
237 static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
238 {
239 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
240 
241 	return irq_find_mapping(port->domain, offset);
242 }
243 
244 static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
245 {
246 	struct mxs_gpio_port *port = gpiochip_get_data(gc);
247 	u32 mask = 1 << offset;
248 	u32 dir;
249 
250 	dir = readl(port->base + PINCTRL_DOE(port));
251 	if (dir & mask)
252 		return GPIO_LINE_DIRECTION_OUT;
253 
254 	return GPIO_LINE_DIRECTION_IN;
255 }
256 
257 static const struct of_device_id mxs_gpio_dt_ids[] = {
258 	{ .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
259 	{ .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
260 	{ /* sentinel */ }
261 };
262 MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
263 
264 static int mxs_gpio_probe(struct platform_device *pdev)
265 {
266 	struct device_node *np = pdev->dev.of_node;
267 	struct device_node *parent;
268 	static void __iomem *base;
269 	struct mxs_gpio_port *port;
270 	int irq_base;
271 	int err;
272 
273 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
274 	if (!port)
275 		return -ENOMEM;
276 
277 	port->id = of_alias_get_id(np, "gpio");
278 	if (port->id < 0)
279 		return port->id;
280 	port->devid = (enum mxs_gpio_id)of_device_get_match_data(&pdev->dev);
281 	port->dev = &pdev->dev;
282 	port->irq = platform_get_irq(pdev, 0);
283 	if (port->irq < 0)
284 		return port->irq;
285 
286 	/*
287 	 * map memory region only once, as all the gpio ports
288 	 * share the same one
289 	 */
290 	if (!base) {
291 		parent = of_get_parent(np);
292 		base = of_iomap(parent, 0);
293 		of_node_put(parent);
294 		if (!base)
295 			return -EADDRNOTAVAIL;
296 	}
297 	port->base = base;
298 
299 	/* initially disable the interrupts */
300 	writel(0, port->base + PINCTRL_PIN2IRQ(port));
301 	writel(0, port->base + PINCTRL_IRQEN(port));
302 
303 	/* clear address has to be used to clear IRQSTAT bits */
304 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
305 
306 	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
307 	if (irq_base < 0) {
308 		err = irq_base;
309 		goto out_iounmap;
310 	}
311 
312 	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
313 					     &irq_domain_simple_ops, NULL);
314 	if (!port->domain) {
315 		err = -ENODEV;
316 		goto out_iounmap;
317 	}
318 
319 	/* gpio-mxs can be a generic irq chip */
320 	err = mxs_gpio_init_gc(port, irq_base);
321 	if (err < 0)
322 		goto out_irqdomain_remove;
323 
324 	/* setup one handler for each entry */
325 	irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
326 					 port);
327 
328 	err = bgpio_init(&port->gc, &pdev->dev, 4,
329 			 port->base + PINCTRL_DIN(port),
330 			 port->base + PINCTRL_DOUT(port) + MXS_SET,
331 			 port->base + PINCTRL_DOUT(port) + MXS_CLR,
332 			 port->base + PINCTRL_DOE(port), NULL, 0);
333 	if (err)
334 		goto out_irqdomain_remove;
335 
336 	port->gc.to_irq = mxs_gpio_to_irq;
337 	port->gc.get_direction = mxs_gpio_get_direction;
338 	port->gc.base = port->id * 32;
339 
340 	err = gpiochip_add_data(&port->gc, port);
341 	if (err)
342 		goto out_irqdomain_remove;
343 
344 	return 0;
345 
346 out_irqdomain_remove:
347 	irq_domain_remove(port->domain);
348 out_iounmap:
349 	iounmap(port->base);
350 	return err;
351 }
352 
353 static struct platform_driver mxs_gpio_driver = {
354 	.driver		= {
355 		.name	= "gpio-mxs",
356 		.of_match_table = mxs_gpio_dt_ids,
357 		.suppress_bind_attrs = true,
358 	},
359 	.probe		= mxs_gpio_probe,
360 };
361 
362 static int __init mxs_gpio_init(void)
363 {
364 	return platform_driver_register(&mxs_gpio_driver);
365 }
366 postcore_initcall(mxs_gpio_init);
367 
368 MODULE_AUTHOR("Freescale Semiconductor, "
369 	      "Daniel Mack <danielncaiaq.de>, "
370 	      "Juergen Beisert <kernel@pengutronix.de>");
371 MODULE_DESCRIPTION("Freescale MXS GPIO");
372 MODULE_LICENSE("GPL");
373