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
is_imx23_gpio(struct mxs_gpio_port * port)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
mxs_gpio_set_irq_type(struct irq_data * d,unsigned int type)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
mxs_flip_edge(struct mxs_gpio_port * port,u32 gpio)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 */
mxs_gpio_irq_handler(struct irq_desc * desc)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 */
mxs_gpio_set_wake_irq(struct irq_data * d,unsigned int enable)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
mxs_gpio_init_gc(struct mxs_gpio_port * port,int irq_base)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
mxs_gpio_to_irq(struct gpio_chip * gc,unsigned int offset)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
mxs_gpio_get_direction(struct gpio_chip * gc,unsigned int offset)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
mxs_gpio_probe(struct platform_device * pdev)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
mxs_gpio_init(void)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