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 Semiconductor,
7 // Authors: Daniel Mack, Juergen Beisert.
8 // Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
9
10 #include <linux/clk.h>
11 #include <linux/err.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/irqchip/chained_irq.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/syscore_ops.h>
21 #include <linux/gpio/driver.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/bug.h>
25
26 enum mxc_gpio_hwtype {
27 IMX1_GPIO, /* runs on i.mx1 */
28 IMX21_GPIO, /* runs on i.mx21 and i.mx27 */
29 IMX31_GPIO, /* runs on i.mx31 */
30 IMX35_GPIO, /* runs on all other i.mx */
31 };
32
33 /* device type dependent stuff */
34 struct mxc_gpio_hwdata {
35 unsigned dr_reg;
36 unsigned gdir_reg;
37 unsigned psr_reg;
38 unsigned icr1_reg;
39 unsigned icr2_reg;
40 unsigned imr_reg;
41 unsigned isr_reg;
42 int edge_sel_reg;
43 unsigned low_level;
44 unsigned high_level;
45 unsigned rise_edge;
46 unsigned fall_edge;
47 };
48
49 struct mxc_gpio_reg_saved {
50 u32 icr1;
51 u32 icr2;
52 u32 imr;
53 u32 gdir;
54 u32 edge_sel;
55 u32 dr;
56 };
57
58 struct mxc_gpio_port {
59 struct list_head node;
60 void __iomem *base;
61 struct clk *clk;
62 int irq;
63 int irq_high;
64 struct irq_domain *domain;
65 struct gpio_chip gc;
66 struct device *dev;
67 u32 both_edges;
68 struct mxc_gpio_reg_saved gpio_saved_reg;
69 bool power_off;
70 };
71
72 static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = {
73 .dr_reg = 0x1c,
74 .gdir_reg = 0x00,
75 .psr_reg = 0x24,
76 .icr1_reg = 0x28,
77 .icr2_reg = 0x2c,
78 .imr_reg = 0x30,
79 .isr_reg = 0x34,
80 .edge_sel_reg = -EINVAL,
81 .low_level = 0x03,
82 .high_level = 0x02,
83 .rise_edge = 0x00,
84 .fall_edge = 0x01,
85 };
86
87 static struct mxc_gpio_hwdata imx31_gpio_hwdata = {
88 .dr_reg = 0x00,
89 .gdir_reg = 0x04,
90 .psr_reg = 0x08,
91 .icr1_reg = 0x0c,
92 .icr2_reg = 0x10,
93 .imr_reg = 0x14,
94 .isr_reg = 0x18,
95 .edge_sel_reg = -EINVAL,
96 .low_level = 0x00,
97 .high_level = 0x01,
98 .rise_edge = 0x02,
99 .fall_edge = 0x03,
100 };
101
102 static struct mxc_gpio_hwdata imx35_gpio_hwdata = {
103 .dr_reg = 0x00,
104 .gdir_reg = 0x04,
105 .psr_reg = 0x08,
106 .icr1_reg = 0x0c,
107 .icr2_reg = 0x10,
108 .imr_reg = 0x14,
109 .isr_reg = 0x18,
110 .edge_sel_reg = 0x1c,
111 .low_level = 0x00,
112 .high_level = 0x01,
113 .rise_edge = 0x02,
114 .fall_edge = 0x03,
115 };
116
117 static enum mxc_gpio_hwtype mxc_gpio_hwtype;
118 static struct mxc_gpio_hwdata *mxc_gpio_hwdata;
119
120 #define GPIO_DR (mxc_gpio_hwdata->dr_reg)
121 #define GPIO_GDIR (mxc_gpio_hwdata->gdir_reg)
122 #define GPIO_PSR (mxc_gpio_hwdata->psr_reg)
123 #define GPIO_ICR1 (mxc_gpio_hwdata->icr1_reg)
124 #define GPIO_ICR2 (mxc_gpio_hwdata->icr2_reg)
125 #define GPIO_IMR (mxc_gpio_hwdata->imr_reg)
126 #define GPIO_ISR (mxc_gpio_hwdata->isr_reg)
127 #define GPIO_EDGE_SEL (mxc_gpio_hwdata->edge_sel_reg)
128
129 #define GPIO_INT_LOW_LEV (mxc_gpio_hwdata->low_level)
130 #define GPIO_INT_HIGH_LEV (mxc_gpio_hwdata->high_level)
131 #define GPIO_INT_RISE_EDGE (mxc_gpio_hwdata->rise_edge)
132 #define GPIO_INT_FALL_EDGE (mxc_gpio_hwdata->fall_edge)
133 #define GPIO_INT_BOTH_EDGES 0x4
134
135 static const struct platform_device_id mxc_gpio_devtype[] = {
136 {
137 .name = "imx1-gpio",
138 .driver_data = IMX1_GPIO,
139 }, {
140 .name = "imx21-gpio",
141 .driver_data = IMX21_GPIO,
142 }, {
143 .name = "imx31-gpio",
144 .driver_data = IMX31_GPIO,
145 }, {
146 .name = "imx35-gpio",
147 .driver_data = IMX35_GPIO,
148 }, {
149 /* sentinel */
150 }
151 };
152
153 static const struct of_device_id mxc_gpio_dt_ids[] = {
154 { .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], },
155 { .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], },
156 { .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], },
157 { .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], },
158 { .compatible = "fsl,imx7d-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], },
159 { /* sentinel */ }
160 };
161
162 /*
163 * MX2 has one interrupt *for all* gpio ports. The list is used
164 * to save the references to all ports, so that mx2_gpio_irq_handler
165 * can walk through all interrupt status registers.
166 */
167 static LIST_HEAD(mxc_gpio_ports);
168
169 /* Note: This driver assumes 32 GPIOs are handled in one register */
170
gpio_set_irq_type(struct irq_data * d,u32 type)171 static int gpio_set_irq_type(struct irq_data *d, u32 type)
172 {
173 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
174 struct mxc_gpio_port *port = gc->private;
175 u32 bit, val;
176 u32 gpio_idx = d->hwirq;
177 int edge;
178 void __iomem *reg = port->base;
179
180 port->both_edges &= ~(1 << gpio_idx);
181 switch (type) {
182 case IRQ_TYPE_EDGE_RISING:
183 edge = GPIO_INT_RISE_EDGE;
184 break;
185 case IRQ_TYPE_EDGE_FALLING:
186 edge = GPIO_INT_FALL_EDGE;
187 break;
188 case IRQ_TYPE_EDGE_BOTH:
189 if (GPIO_EDGE_SEL >= 0) {
190 edge = GPIO_INT_BOTH_EDGES;
191 } else {
192 val = port->gc.get(&port->gc, gpio_idx);
193 if (val) {
194 edge = GPIO_INT_LOW_LEV;
195 pr_debug("mxc: set GPIO %d to low trigger\n", gpio_idx);
196 } else {
197 edge = GPIO_INT_HIGH_LEV;
198 pr_debug("mxc: set GPIO %d to high trigger\n", gpio_idx);
199 }
200 port->both_edges |= 1 << gpio_idx;
201 }
202 break;
203 case IRQ_TYPE_LEVEL_LOW:
204 edge = GPIO_INT_LOW_LEV;
205 break;
206 case IRQ_TYPE_LEVEL_HIGH:
207 edge = GPIO_INT_HIGH_LEV;
208 break;
209 default:
210 return -EINVAL;
211 }
212
213 if (GPIO_EDGE_SEL >= 0) {
214 val = readl(port->base + GPIO_EDGE_SEL);
215 if (edge == GPIO_INT_BOTH_EDGES)
216 writel(val | (1 << gpio_idx),
217 port->base + GPIO_EDGE_SEL);
218 else
219 writel(val & ~(1 << gpio_idx),
220 port->base + GPIO_EDGE_SEL);
221 }
222
223 if (edge != GPIO_INT_BOTH_EDGES) {
224 reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
225 bit = gpio_idx & 0xf;
226 val = readl(reg) & ~(0x3 << (bit << 1));
227 writel(val | (edge << (bit << 1)), reg);
228 }
229
230 writel(1 << gpio_idx, port->base + GPIO_ISR);
231
232 return 0;
233 }
234
mxc_flip_edge(struct mxc_gpio_port * port,u32 gpio)235 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
236 {
237 void __iomem *reg = port->base;
238 u32 bit, val;
239 int edge;
240
241 reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
242 bit = gpio & 0xf;
243 val = readl(reg);
244 edge = (val >> (bit << 1)) & 3;
245 val &= ~(0x3 << (bit << 1));
246 if (edge == GPIO_INT_HIGH_LEV) {
247 edge = GPIO_INT_LOW_LEV;
248 pr_debug("mxc: switch GPIO %d to low trigger\n", gpio);
249 } else if (edge == GPIO_INT_LOW_LEV) {
250 edge = GPIO_INT_HIGH_LEV;
251 pr_debug("mxc: switch GPIO %d to high trigger\n", gpio);
252 } else {
253 pr_err("mxc: invalid configuration for GPIO %d: %x\n",
254 gpio, edge);
255 return;
256 }
257 writel(val | (edge << (bit << 1)), reg);
258 }
259
260 /* handle 32 interrupts in one status register */
mxc_gpio_irq_handler(struct mxc_gpio_port * port,u32 irq_stat)261 static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
262 {
263 while (irq_stat != 0) {
264 int irqoffset = fls(irq_stat) - 1;
265
266 if (port->both_edges & (1 << irqoffset))
267 mxc_flip_edge(port, irqoffset);
268
269 generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
270
271 irq_stat &= ~(1 << irqoffset);
272 }
273 }
274
275 /* MX1 and MX3 has one interrupt *per* gpio port */
mx3_gpio_irq_handler(struct irq_desc * desc)276 static void mx3_gpio_irq_handler(struct irq_desc *desc)
277 {
278 u32 irq_stat;
279 struct mxc_gpio_port *port = irq_desc_get_handler_data(desc);
280 struct irq_chip *chip = irq_desc_get_chip(desc);
281
282 chained_irq_enter(chip, desc);
283
284 irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR);
285
286 mxc_gpio_irq_handler(port, irq_stat);
287
288 chained_irq_exit(chip, desc);
289 }
290
291 /* MX2 has one interrupt *for all* gpio ports */
mx2_gpio_irq_handler(struct irq_desc * desc)292 static void mx2_gpio_irq_handler(struct irq_desc *desc)
293 {
294 u32 irq_msk, irq_stat;
295 struct mxc_gpio_port *port;
296 struct irq_chip *chip = irq_desc_get_chip(desc);
297
298 chained_irq_enter(chip, desc);
299
300 /* walk through all interrupt status registers */
301 list_for_each_entry(port, &mxc_gpio_ports, node) {
302 irq_msk = readl(port->base + GPIO_IMR);
303 if (!irq_msk)
304 continue;
305
306 irq_stat = readl(port->base + GPIO_ISR) & irq_msk;
307 if (irq_stat)
308 mxc_gpio_irq_handler(port, irq_stat);
309 }
310 chained_irq_exit(chip, desc);
311 }
312
313 /*
314 * Set interrupt number "irq" in the GPIO as a wake-up source.
315 * While system is running, all registered GPIO interrupts need to have
316 * wake-up enabled. When system is suspended, only selected GPIO interrupts
317 * need to have wake-up enabled.
318 * @param irq interrupt source number
319 * @param enable enable as wake-up if equal to non-zero
320 * @return This function returns 0 on success.
321 */
gpio_set_wake_irq(struct irq_data * d,u32 enable)322 static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
323 {
324 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
325 struct mxc_gpio_port *port = gc->private;
326 u32 gpio_idx = d->hwirq;
327 int ret;
328
329 if (enable) {
330 if (port->irq_high && (gpio_idx >= 16))
331 ret = enable_irq_wake(port->irq_high);
332 else
333 ret = enable_irq_wake(port->irq);
334 } else {
335 if (port->irq_high && (gpio_idx >= 16))
336 ret = disable_irq_wake(port->irq_high);
337 else
338 ret = disable_irq_wake(port->irq);
339 }
340
341 return ret;
342 }
343
mxc_gpio_init_gc(struct mxc_gpio_port * port,int irq_base)344 static int mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base)
345 {
346 struct irq_chip_generic *gc;
347 struct irq_chip_type *ct;
348 int rv;
349
350 gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxc", 1, irq_base,
351 port->base, handle_level_irq);
352 if (!gc)
353 return -ENOMEM;
354 gc->private = port;
355
356 ct = gc->chip_types;
357 ct->chip.irq_ack = irq_gc_ack_set_bit;
358 ct->chip.irq_mask = irq_gc_mask_clr_bit;
359 ct->chip.irq_unmask = irq_gc_mask_set_bit;
360 ct->chip.irq_set_type = gpio_set_irq_type;
361 ct->chip.irq_set_wake = gpio_set_wake_irq;
362 ct->chip.flags = IRQCHIP_MASK_ON_SUSPEND;
363 ct->regs.ack = GPIO_ISR;
364 ct->regs.mask = GPIO_IMR;
365
366 rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
367 IRQ_GC_INIT_NESTED_LOCK,
368 IRQ_NOREQUEST, 0);
369
370 return rv;
371 }
372
mxc_gpio_get_hw(struct platform_device * pdev)373 static void mxc_gpio_get_hw(struct platform_device *pdev)
374 {
375 const struct of_device_id *of_id =
376 of_match_device(mxc_gpio_dt_ids, &pdev->dev);
377 enum mxc_gpio_hwtype hwtype;
378
379 if (of_id)
380 pdev->id_entry = of_id->data;
381 hwtype = pdev->id_entry->driver_data;
382
383 if (mxc_gpio_hwtype) {
384 /*
385 * The driver works with a reasonable presupposition,
386 * that is all gpio ports must be the same type when
387 * running on one soc.
388 */
389 BUG_ON(mxc_gpio_hwtype != hwtype);
390 return;
391 }
392
393 if (hwtype == IMX35_GPIO)
394 mxc_gpio_hwdata = &imx35_gpio_hwdata;
395 else if (hwtype == IMX31_GPIO)
396 mxc_gpio_hwdata = &imx31_gpio_hwdata;
397 else
398 mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata;
399
400 mxc_gpio_hwtype = hwtype;
401 }
402
mxc_gpio_to_irq(struct gpio_chip * gc,unsigned offset)403 static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
404 {
405 struct mxc_gpio_port *port = gpiochip_get_data(gc);
406
407 return irq_find_mapping(port->domain, offset);
408 }
409
mxc_gpio_probe(struct platform_device * pdev)410 static int mxc_gpio_probe(struct platform_device *pdev)
411 {
412 struct device_node *np = pdev->dev.of_node;
413 struct mxc_gpio_port *port;
414 struct resource *iores;
415 int irq_base;
416 int err;
417
418 mxc_gpio_get_hw(pdev);
419
420 port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
421 if (!port)
422 return -ENOMEM;
423
424 port->dev = &pdev->dev;
425
426 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
427 port->base = devm_ioremap_resource(&pdev->dev, iores);
428 if (IS_ERR(port->base))
429 return PTR_ERR(port->base);
430
431 port->irq_high = platform_get_irq(pdev, 1);
432 if (port->irq_high < 0)
433 port->irq_high = 0;
434
435 port->irq = platform_get_irq(pdev, 0);
436 if (port->irq < 0)
437 return port->irq;
438
439 /* the controller clock is optional */
440 port->clk = devm_clk_get(&pdev->dev, NULL);
441 if (IS_ERR(port->clk)) {
442 if (PTR_ERR(port->clk) == -EPROBE_DEFER)
443 return -EPROBE_DEFER;
444 port->clk = NULL;
445 }
446
447 err = clk_prepare_enable(port->clk);
448 if (err) {
449 dev_err(&pdev->dev, "Unable to enable clock.\n");
450 return err;
451 }
452
453 if (of_device_is_compatible(np, "fsl,imx7d-gpio"))
454 port->power_off = true;
455
456 /* disable the interrupt and clear the status */
457 writel(0, port->base + GPIO_IMR);
458 writel(~0, port->base + GPIO_ISR);
459
460 if (mxc_gpio_hwtype == IMX21_GPIO) {
461 /*
462 * Setup one handler for all GPIO interrupts. Actually setting
463 * the handler is needed only once, but doing it for every port
464 * is more robust and easier.
465 */
466 irq_set_chained_handler(port->irq, mx2_gpio_irq_handler);
467 } else {
468 /* setup one handler for each entry */
469 irq_set_chained_handler_and_data(port->irq,
470 mx3_gpio_irq_handler, port);
471 if (port->irq_high > 0)
472 /* setup handler for GPIO 16 to 31 */
473 irq_set_chained_handler_and_data(port->irq_high,
474 mx3_gpio_irq_handler,
475 port);
476 }
477
478 err = bgpio_init(&port->gc, &pdev->dev, 4,
479 port->base + GPIO_PSR,
480 port->base + GPIO_DR, NULL,
481 port->base + GPIO_GDIR, NULL,
482 BGPIOF_READ_OUTPUT_REG_SET);
483 if (err)
484 goto out_bgio;
485
486 if (of_property_read_bool(np, "gpio-ranges")) {
487 port->gc.request = gpiochip_generic_request;
488 port->gc.free = gpiochip_generic_free;
489 }
490
491 port->gc.to_irq = mxc_gpio_to_irq;
492 port->gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 :
493 pdev->id * 32;
494
495 err = devm_gpiochip_add_data(&pdev->dev, &port->gc, port);
496 if (err)
497 goto out_bgio;
498
499 irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
500 if (irq_base < 0) {
501 err = irq_base;
502 goto out_bgio;
503 }
504
505 port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
506 &irq_domain_simple_ops, NULL);
507 if (!port->domain) {
508 err = -ENODEV;
509 goto out_bgio;
510 }
511
512 /* gpio-mxc can be a generic irq chip */
513 err = mxc_gpio_init_gc(port, irq_base);
514 if (err < 0)
515 goto out_irqdomain_remove;
516
517 list_add_tail(&port->node, &mxc_gpio_ports);
518
519 platform_set_drvdata(pdev, port);
520
521 return 0;
522
523 out_irqdomain_remove:
524 irq_domain_remove(port->domain);
525 out_bgio:
526 clk_disable_unprepare(port->clk);
527 dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
528 return err;
529 }
530
mxc_gpio_save_regs(struct mxc_gpio_port * port)531 static void mxc_gpio_save_regs(struct mxc_gpio_port *port)
532 {
533 if (!port->power_off)
534 return;
535
536 port->gpio_saved_reg.icr1 = readl(port->base + GPIO_ICR1);
537 port->gpio_saved_reg.icr2 = readl(port->base + GPIO_ICR2);
538 port->gpio_saved_reg.imr = readl(port->base + GPIO_IMR);
539 port->gpio_saved_reg.gdir = readl(port->base + GPIO_GDIR);
540 port->gpio_saved_reg.edge_sel = readl(port->base + GPIO_EDGE_SEL);
541 port->gpio_saved_reg.dr = readl(port->base + GPIO_DR);
542 }
543
mxc_gpio_restore_regs(struct mxc_gpio_port * port)544 static void mxc_gpio_restore_regs(struct mxc_gpio_port *port)
545 {
546 if (!port->power_off)
547 return;
548
549 writel(port->gpio_saved_reg.icr1, port->base + GPIO_ICR1);
550 writel(port->gpio_saved_reg.icr2, port->base + GPIO_ICR2);
551 writel(port->gpio_saved_reg.imr, port->base + GPIO_IMR);
552 writel(port->gpio_saved_reg.gdir, port->base + GPIO_GDIR);
553 writel(port->gpio_saved_reg.edge_sel, port->base + GPIO_EDGE_SEL);
554 writel(port->gpio_saved_reg.dr, port->base + GPIO_DR);
555 }
556
mxc_gpio_syscore_suspend(void)557 static int mxc_gpio_syscore_suspend(void)
558 {
559 struct mxc_gpio_port *port;
560
561 /* walk through all ports */
562 list_for_each_entry(port, &mxc_gpio_ports, node) {
563 mxc_gpio_save_regs(port);
564 clk_disable_unprepare(port->clk);
565 }
566
567 return 0;
568 }
569
mxc_gpio_syscore_resume(void)570 static void mxc_gpio_syscore_resume(void)
571 {
572 struct mxc_gpio_port *port;
573 int ret;
574
575 /* walk through all ports */
576 list_for_each_entry(port, &mxc_gpio_ports, node) {
577 ret = clk_prepare_enable(port->clk);
578 if (ret) {
579 pr_err("mxc: failed to enable gpio clock %d\n", ret);
580 return;
581 }
582 mxc_gpio_restore_regs(port);
583 }
584 }
585
586 static struct syscore_ops mxc_gpio_syscore_ops = {
587 .suspend = mxc_gpio_syscore_suspend,
588 .resume = mxc_gpio_syscore_resume,
589 };
590
591 static struct platform_driver mxc_gpio_driver = {
592 .driver = {
593 .name = "gpio-mxc",
594 .of_match_table = mxc_gpio_dt_ids,
595 .suppress_bind_attrs = true,
596 },
597 .probe = mxc_gpio_probe,
598 .id_table = mxc_gpio_devtype,
599 };
600
gpio_mxc_init(void)601 static int __init gpio_mxc_init(void)
602 {
603 register_syscore_ops(&mxc_gpio_syscore_ops);
604
605 return platform_driver_register(&mxc_gpio_driver);
606 }
607 subsys_initcall(gpio_mxc_init);
608