xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision ca55b2fe)
1 /*
2  * GPIOs on MPC512x/8349/8572/8610 and compatible
3  *
4  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
5  *
6  * This file is licensed under the terms of the GNU General Public License
7  * version 2.  This program is licensed "as is" without any warranty of any
8  * kind, whether express or implied.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/spinlock.h>
14 #include <linux/io.h>
15 #include <linux/of.h>
16 #include <linux/of_gpio.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_platform.h>
19 #include <linux/gpio.h>
20 #include <linux/slab.h>
21 #include <linux/irq.h>
22 
23 #define MPC8XXX_GPIO_PINS	32
24 
25 #define GPIO_DIR		0x00
26 #define GPIO_ODR		0x04
27 #define GPIO_DAT		0x08
28 #define GPIO_IER		0x0c
29 #define GPIO_IMR		0x10
30 #define GPIO_ICR		0x14
31 #define GPIO_ICR2		0x18
32 
33 struct mpc8xxx_gpio_chip {
34 	struct of_mm_gpio_chip mm_gc;
35 	raw_spinlock_t lock;
36 
37 	/*
38 	 * shadowed data register to be able to clear/set output pins in
39 	 * open drain mode safely
40 	 */
41 	u32 data;
42 	struct irq_domain *irq;
43 	unsigned int irqn;
44 	const void *of_dev_id_data;
45 };
46 
47 static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
48 {
49 	return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio);
50 }
51 
52 static inline struct mpc8xxx_gpio_chip *
53 to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm)
54 {
55 	return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc);
56 }
57 
58 static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm)
59 {
60 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
61 
62 	mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT);
63 }
64 
65 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
66  * defined as output cannot be determined by reading GPDAT register,
67  * so we use shadow data register instead. The status of input pins
68  * is determined by reading GPDAT register.
69  */
70 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
71 {
72 	u32 val;
73 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
74 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
75 	u32 out_mask, out_shadow;
76 
77 	out_mask = in_be32(mm->regs + GPIO_DIR);
78 
79 	val = in_be32(mm->regs + GPIO_DAT) & ~out_mask;
80 	out_shadow = mpc8xxx_gc->data & out_mask;
81 
82 	return (val | out_shadow) & mpc8xxx_gpio2mask(gpio);
83 }
84 
85 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
86 {
87 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
88 
89 	return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
90 }
91 
92 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
93 {
94 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
95 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
96 	unsigned long flags;
97 
98 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
99 
100 	if (val)
101 		mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
102 	else
103 		mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
104 
105 	out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
106 
107 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
108 }
109 
110 static void mpc8xxx_gpio_set_multiple(struct gpio_chip *gc,
111 				      unsigned long *mask, unsigned long *bits)
112 {
113 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
114 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
115 	unsigned long flags;
116 	int i;
117 
118 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
119 
120 	for (i = 0; i < gc->ngpio; i++) {
121 		if (*mask == 0)
122 			break;
123 		if (__test_and_clear_bit(i, mask)) {
124 			if (test_bit(i, bits))
125 				mpc8xxx_gc->data |= mpc8xxx_gpio2mask(i);
126 			else
127 				mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(i);
128 		}
129 	}
130 
131 	out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
132 
133 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
134 }
135 
136 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
137 {
138 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
139 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
140 	unsigned long flags;
141 
142 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
143 
144 	clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
145 
146 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
147 
148 	return 0;
149 }
150 
151 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
152 {
153 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
154 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
155 	unsigned long flags;
156 
157 	mpc8xxx_gpio_set(gc, gpio, val);
158 
159 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
160 
161 	setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
162 
163 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
164 
165 	return 0;
166 }
167 
168 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
169 {
170 	/* GPIO 28..31 are input only on MPC5121 */
171 	if (gpio >= 28)
172 		return -EINVAL;
173 
174 	return mpc8xxx_gpio_dir_out(gc, gpio, val);
175 }
176 
177 static int mpc5125_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
178 {
179 	/* GPIO 0..3 are input only on MPC5125 */
180 	if (gpio <= 3)
181 		return -EINVAL;
182 
183 	return mpc8xxx_gpio_dir_out(gc, gpio, val);
184 }
185 
186 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
187 {
188 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
189 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
190 
191 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
192 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
193 	else
194 		return -ENXIO;
195 }
196 
197 static void mpc8xxx_gpio_irq_cascade(struct irq_desc *desc)
198 {
199 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
200 	struct irq_chip *chip = irq_desc_get_chip(desc);
201 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
202 	unsigned int mask;
203 
204 	mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
205 	if (mask)
206 		generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
207 						     32 - ffs(mask)));
208 	if (chip->irq_eoi)
209 		chip->irq_eoi(&desc->irq_data);
210 }
211 
212 static void mpc8xxx_irq_unmask(struct irq_data *d)
213 {
214 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
215 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
216 	unsigned long flags;
217 
218 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
219 
220 	setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
221 
222 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
223 }
224 
225 static void mpc8xxx_irq_mask(struct irq_data *d)
226 {
227 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
228 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
229 	unsigned long flags;
230 
231 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
232 
233 	clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
234 
235 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
236 }
237 
238 static void mpc8xxx_irq_ack(struct irq_data *d)
239 {
240 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
241 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
242 
243 	out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
244 }
245 
246 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
247 {
248 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
249 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
250 	unsigned long flags;
251 
252 	switch (flow_type) {
253 	case IRQ_TYPE_EDGE_FALLING:
254 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
255 		setbits32(mm->regs + GPIO_ICR,
256 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
257 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
258 		break;
259 
260 	case IRQ_TYPE_EDGE_BOTH:
261 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
262 		clrbits32(mm->regs + GPIO_ICR,
263 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
264 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
265 		break;
266 
267 	default:
268 		return -EINVAL;
269 	}
270 
271 	return 0;
272 }
273 
274 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
275 {
276 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
277 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
278 	unsigned long gpio = irqd_to_hwirq(d);
279 	void __iomem *reg;
280 	unsigned int shift;
281 	unsigned long flags;
282 
283 	if (gpio < 16) {
284 		reg = mm->regs + GPIO_ICR;
285 		shift = (15 - gpio) * 2;
286 	} else {
287 		reg = mm->regs + GPIO_ICR2;
288 		shift = (15 - (gpio % 16)) * 2;
289 	}
290 
291 	switch (flow_type) {
292 	case IRQ_TYPE_EDGE_FALLING:
293 	case IRQ_TYPE_LEVEL_LOW:
294 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
295 		clrsetbits_be32(reg, 3 << shift, 2 << shift);
296 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
297 		break;
298 
299 	case IRQ_TYPE_EDGE_RISING:
300 	case IRQ_TYPE_LEVEL_HIGH:
301 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
302 		clrsetbits_be32(reg, 3 << shift, 1 << shift);
303 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
304 		break;
305 
306 	case IRQ_TYPE_EDGE_BOTH:
307 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
308 		clrbits32(reg, 3 << shift);
309 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
310 		break;
311 
312 	default:
313 		return -EINVAL;
314 	}
315 
316 	return 0;
317 }
318 
319 static struct irq_chip mpc8xxx_irq_chip = {
320 	.name		= "mpc8xxx-gpio",
321 	.irq_unmask	= mpc8xxx_irq_unmask,
322 	.irq_mask	= mpc8xxx_irq_mask,
323 	.irq_ack	= mpc8xxx_irq_ack,
324 	/* this might get overwritten in mpc8xxx_probe() */
325 	.irq_set_type	= mpc8xxx_irq_set_type,
326 };
327 
328 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
329 				irq_hw_number_t hwirq)
330 {
331 	irq_set_chip_data(irq, h->host_data);
332 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_level_irq);
333 
334 	return 0;
335 }
336 
337 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
338 	.map	= mpc8xxx_gpio_irq_map,
339 	.xlate	= irq_domain_xlate_twocell,
340 };
341 
342 struct mpc8xxx_gpio_devtype {
343 	int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
344 	int (*gpio_get)(struct gpio_chip *, unsigned int);
345 	int (*irq_set_type)(struct irq_data *, unsigned int);
346 };
347 
348 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
349 	.gpio_dir_out = mpc5121_gpio_dir_out,
350 	.irq_set_type = mpc512x_irq_set_type,
351 };
352 
353 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
354 	.gpio_dir_out = mpc5125_gpio_dir_out,
355 	.irq_set_type = mpc512x_irq_set_type,
356 };
357 
358 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
359 	.gpio_get = mpc8572_gpio_get,
360 };
361 
362 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
363 	.gpio_dir_out = mpc8xxx_gpio_dir_out,
364 	.gpio_get = mpc8xxx_gpio_get,
365 	.irq_set_type = mpc8xxx_irq_set_type,
366 };
367 
368 static const struct of_device_id mpc8xxx_gpio_ids[] = {
369 	{ .compatible = "fsl,mpc8349-gpio", },
370 	{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
371 	{ .compatible = "fsl,mpc8610-gpio", },
372 	{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
373 	{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
374 	{ .compatible = "fsl,pq3-gpio",     },
375 	{ .compatible = "fsl,qoriq-gpio",   },
376 	{}
377 };
378 
379 static int mpc8xxx_probe(struct platform_device *pdev)
380 {
381 	struct device_node *np = pdev->dev.of_node;
382 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
383 	struct of_mm_gpio_chip *mm_gc;
384 	struct gpio_chip *gc;
385 	const struct of_device_id *id;
386 	const struct mpc8xxx_gpio_devtype *devtype =
387 		of_device_get_match_data(&pdev->dev);
388 	int ret;
389 
390 	mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
391 	if (!mpc8xxx_gc)
392 		return -ENOMEM;
393 
394 	platform_set_drvdata(pdev, mpc8xxx_gc);
395 
396 	raw_spin_lock_init(&mpc8xxx_gc->lock);
397 
398 	mm_gc = &mpc8xxx_gc->mm_gc;
399 	gc = &mm_gc->gc;
400 
401 	mm_gc->save_regs = mpc8xxx_gpio_save_regs;
402 	gc->ngpio = MPC8XXX_GPIO_PINS;
403 	gc->direction_input = mpc8xxx_gpio_dir_in;
404 
405 	if (!devtype)
406 		devtype = &mpc8xxx_gpio_devtype_default;
407 
408 	/*
409 	 * It's assumed that only a single type of gpio controller is available
410 	 * on the current machine, so overwriting global data is fine.
411 	 */
412 	mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
413 
414 	gc->direction_output = devtype->gpio_dir_out ?: mpc8xxx_gpio_dir_out;
415 	gc->get = devtype->gpio_get ?: mpc8xxx_gpio_get;
416 	gc->set = mpc8xxx_gpio_set;
417 	gc->set_multiple = mpc8xxx_gpio_set_multiple;
418 	gc->to_irq = mpc8xxx_gpio_to_irq;
419 
420 	ret = of_mm_gpiochip_add(np, mm_gc);
421 	if (ret)
422 		return ret;
423 
424 	mpc8xxx_gc->irqn = irq_of_parse_and_map(np, 0);
425 	if (mpc8xxx_gc->irqn == NO_IRQ)
426 		return 0;
427 
428 	mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
429 					&mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
430 	if (!mpc8xxx_gc->irq)
431 		return 0;
432 
433 	id = of_match_node(mpc8xxx_gpio_ids, np);
434 	if (id)
435 		mpc8xxx_gc->of_dev_id_data = id->data;
436 
437 	/* ack and mask all irqs */
438 	out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
439 	out_be32(mm_gc->regs + GPIO_IMR, 0);
440 
441 	irq_set_chained_handler_and_data(mpc8xxx_gc->irqn,
442 					 mpc8xxx_gpio_irq_cascade, mpc8xxx_gc);
443 
444 	return 0;
445 }
446 
447 static int mpc8xxx_remove(struct platform_device *pdev)
448 {
449 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
450 
451 	if (mpc8xxx_gc->irq) {
452 		irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
453 		irq_domain_remove(mpc8xxx_gc->irq);
454 	}
455 
456 	of_mm_gpiochip_remove(&mpc8xxx_gc->mm_gc);
457 
458 	return 0;
459 }
460 
461 static struct platform_driver mpc8xxx_plat_driver = {
462 	.probe		= mpc8xxx_probe,
463 	.remove		= mpc8xxx_remove,
464 	.driver		= {
465 		.name = "gpio-mpc8xxx",
466 		.of_match_table	= mpc8xxx_gpio_ids,
467 	},
468 };
469 
470 static int __init mpc8xxx_init(void)
471 {
472 	return platform_driver_register(&mpc8xxx_plat_driver);
473 }
474 
475 arch_initcall(mpc8xxx_init);
476