xref: /linux/drivers/gpio/gpio-mpc8xxx.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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/gpio.h>
18 #include <linux/slab.h>
19 #include <linux/irq.h>
20 
21 #define MPC8XXX_GPIO_PINS	32
22 
23 #define GPIO_DIR		0x00
24 #define GPIO_ODR		0x04
25 #define GPIO_DAT		0x08
26 #define GPIO_IER		0x0c
27 #define GPIO_IMR		0x10
28 #define GPIO_ICR		0x14
29 #define GPIO_ICR2		0x18
30 
31 struct mpc8xxx_gpio_chip {
32 	struct of_mm_gpio_chip mm_gc;
33 	spinlock_t lock;
34 
35 	/*
36 	 * shadowed data register to be able to clear/set output pins in
37 	 * open drain mode safely
38 	 */
39 	u32 data;
40 	struct irq_domain *irq;
41 	const void *of_dev_id_data;
42 };
43 
44 static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
45 {
46 	return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio);
47 }
48 
49 static inline struct mpc8xxx_gpio_chip *
50 to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm)
51 {
52 	return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc);
53 }
54 
55 static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm)
56 {
57 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
58 
59 	mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT);
60 }
61 
62 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
63  * defined as output cannot be determined by reading GPDAT register,
64  * so we use shadow data register instead. The status of input pins
65  * is determined by reading GPDAT register.
66  */
67 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
68 {
69 	u32 val;
70 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
71 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
72 
73 	val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR);
74 
75 	return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio);
76 }
77 
78 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
79 {
80 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
81 
82 	return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
83 }
84 
85 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
86 {
87 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
88 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
89 	unsigned long flags;
90 
91 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
92 
93 	if (val)
94 		mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
95 	else
96 		mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
97 
98 	out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
99 
100 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
101 }
102 
103 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
104 {
105 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
106 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
107 	unsigned long flags;
108 
109 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
110 
111 	clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
112 
113 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
114 
115 	return 0;
116 }
117 
118 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
119 {
120 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
121 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
122 	unsigned long flags;
123 
124 	mpc8xxx_gpio_set(gc, gpio, val);
125 
126 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
127 
128 	setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
129 
130 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
131 
132 	return 0;
133 }
134 
135 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
136 {
137 	/* GPIO 28..31 are input only on MPC5121 */
138 	if (gpio >= 28)
139 		return -EINVAL;
140 
141 	return mpc8xxx_gpio_dir_out(gc, gpio, val);
142 }
143 
144 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
145 {
146 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
147 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
148 
149 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
150 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
151 	else
152 		return -ENXIO;
153 }
154 
155 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
156 {
157 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
158 	struct irq_chip *chip = irq_desc_get_chip(desc);
159 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
160 	unsigned int mask;
161 
162 	mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
163 	if (mask)
164 		generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
165 						     32 - ffs(mask)));
166 	if (chip->irq_eoi)
167 		chip->irq_eoi(&desc->irq_data);
168 }
169 
170 static void mpc8xxx_irq_unmask(struct irq_data *d)
171 {
172 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
173 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
174 	unsigned long flags;
175 
176 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
177 
178 	setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
179 
180 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
181 }
182 
183 static void mpc8xxx_irq_mask(struct irq_data *d)
184 {
185 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
186 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
187 	unsigned long flags;
188 
189 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
190 
191 	clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
192 
193 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
194 }
195 
196 static void mpc8xxx_irq_ack(struct irq_data *d)
197 {
198 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
199 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
200 
201 	out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
202 }
203 
204 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
205 {
206 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
207 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
208 	unsigned long flags;
209 
210 	switch (flow_type) {
211 	case IRQ_TYPE_EDGE_FALLING:
212 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
213 		setbits32(mm->regs + GPIO_ICR,
214 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
215 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
216 		break;
217 
218 	case IRQ_TYPE_EDGE_BOTH:
219 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
220 		clrbits32(mm->regs + GPIO_ICR,
221 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
222 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
223 		break;
224 
225 	default:
226 		return -EINVAL;
227 	}
228 
229 	return 0;
230 }
231 
232 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
233 {
234 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
235 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
236 	unsigned long gpio = irqd_to_hwirq(d);
237 	void __iomem *reg;
238 	unsigned int shift;
239 	unsigned long flags;
240 
241 	if (gpio < 16) {
242 		reg = mm->regs + GPIO_ICR;
243 		shift = (15 - gpio) * 2;
244 	} else {
245 		reg = mm->regs + GPIO_ICR2;
246 		shift = (15 - (gpio % 16)) * 2;
247 	}
248 
249 	switch (flow_type) {
250 	case IRQ_TYPE_EDGE_FALLING:
251 	case IRQ_TYPE_LEVEL_LOW:
252 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
253 		clrsetbits_be32(reg, 3 << shift, 2 << shift);
254 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
255 		break;
256 
257 	case IRQ_TYPE_EDGE_RISING:
258 	case IRQ_TYPE_LEVEL_HIGH:
259 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
260 		clrsetbits_be32(reg, 3 << shift, 1 << shift);
261 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
262 		break;
263 
264 	case IRQ_TYPE_EDGE_BOTH:
265 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
266 		clrbits32(reg, 3 << shift);
267 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
268 		break;
269 
270 	default:
271 		return -EINVAL;
272 	}
273 
274 	return 0;
275 }
276 
277 static struct irq_chip mpc8xxx_irq_chip = {
278 	.name		= "mpc8xxx-gpio",
279 	.irq_unmask	= mpc8xxx_irq_unmask,
280 	.irq_mask	= mpc8xxx_irq_mask,
281 	.irq_ack	= mpc8xxx_irq_ack,
282 	.irq_set_type	= mpc8xxx_irq_set_type,
283 };
284 
285 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int virq,
286 				irq_hw_number_t hw)
287 {
288 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
289 
290 	if (mpc8xxx_gc->of_dev_id_data)
291 		mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
292 
293 	irq_set_chip_data(virq, h->host_data);
294 	irq_set_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_level_irq);
295 	irq_set_irq_type(virq, IRQ_TYPE_NONE);
296 
297 	return 0;
298 }
299 
300 static struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
301 	.map	= mpc8xxx_gpio_irq_map,
302 	.xlate	= irq_domain_xlate_twocell,
303 };
304 
305 static struct of_device_id mpc8xxx_gpio_ids[] __initdata = {
306 	{ .compatible = "fsl,mpc8349-gpio", },
307 	{ .compatible = "fsl,mpc8572-gpio", },
308 	{ .compatible = "fsl,mpc8610-gpio", },
309 	{ .compatible = "fsl,mpc5121-gpio", .data = mpc512x_irq_set_type, },
310 	{ .compatible = "fsl,pq3-gpio",     },
311 	{ .compatible = "fsl,qoriq-gpio",   },
312 	{}
313 };
314 
315 static void __init mpc8xxx_add_controller(struct device_node *np)
316 {
317 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
318 	struct of_mm_gpio_chip *mm_gc;
319 	struct gpio_chip *gc;
320 	const struct of_device_id *id;
321 	unsigned hwirq;
322 	int ret;
323 
324 	mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
325 	if (!mpc8xxx_gc) {
326 		ret = -ENOMEM;
327 		goto err;
328 	}
329 
330 	spin_lock_init(&mpc8xxx_gc->lock);
331 
332 	mm_gc = &mpc8xxx_gc->mm_gc;
333 	gc = &mm_gc->gc;
334 
335 	mm_gc->save_regs = mpc8xxx_gpio_save_regs;
336 	gc->ngpio = MPC8XXX_GPIO_PINS;
337 	gc->direction_input = mpc8xxx_gpio_dir_in;
338 	gc->direction_output = of_device_is_compatible(np, "fsl,mpc5121-gpio") ?
339 		mpc5121_gpio_dir_out : mpc8xxx_gpio_dir_out;
340 	gc->get = of_device_is_compatible(np, "fsl,mpc8572-gpio") ?
341 		mpc8572_gpio_get : mpc8xxx_gpio_get;
342 	gc->set = mpc8xxx_gpio_set;
343 	gc->to_irq = mpc8xxx_gpio_to_irq;
344 
345 	ret = of_mm_gpiochip_add(np, mm_gc);
346 	if (ret)
347 		goto err;
348 
349 	hwirq = irq_of_parse_and_map(np, 0);
350 	if (hwirq == NO_IRQ)
351 		goto skip_irq;
352 
353 	mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
354 					&mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
355 	if (!mpc8xxx_gc->irq)
356 		goto skip_irq;
357 
358 	id = of_match_node(mpc8xxx_gpio_ids, np);
359 	if (id)
360 		mpc8xxx_gc->of_dev_id_data = id->data;
361 
362 	/* ack and mask all irqs */
363 	out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
364 	out_be32(mm_gc->regs + GPIO_IMR, 0);
365 
366 	irq_set_handler_data(hwirq, mpc8xxx_gc);
367 	irq_set_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
368 
369 skip_irq:
370 	return;
371 
372 err:
373 	pr_err("%s: registration failed with status %d\n",
374 	       np->full_name, ret);
375 	kfree(mpc8xxx_gc);
376 
377 	return;
378 }
379 
380 static int __init mpc8xxx_add_gpiochips(void)
381 {
382 	struct device_node *np;
383 
384 	for_each_matching_node(np, mpc8xxx_gpio_ids)
385 		mpc8xxx_add_controller(np);
386 
387 	return 0;
388 }
389 arch_initcall(mpc8xxx_add_gpiochips);
390