xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision 089a49b6)
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/gpio.h>
19 #include <linux/slab.h>
20 #include <linux/irq.h>
21 
22 #define MPC8XXX_GPIO_PINS	32
23 
24 #define GPIO_DIR		0x00
25 #define GPIO_ODR		0x04
26 #define GPIO_DAT		0x08
27 #define GPIO_IER		0x0c
28 #define GPIO_IMR		0x10
29 #define GPIO_ICR		0x14
30 #define GPIO_ICR2		0x18
31 
32 struct mpc8xxx_gpio_chip {
33 	struct of_mm_gpio_chip mm_gc;
34 	spinlock_t lock;
35 
36 	/*
37 	 * shadowed data register to be able to clear/set output pins in
38 	 * open drain mode safely
39 	 */
40 	u32 data;
41 	struct irq_domain *irq;
42 	const void *of_dev_id_data;
43 };
44 
45 static inline u32 mpc8xxx_gpio2mask(unsigned int gpio)
46 {
47 	return 1u << (MPC8XXX_GPIO_PINS - 1 - gpio);
48 }
49 
50 static inline struct mpc8xxx_gpio_chip *
51 to_mpc8xxx_gpio_chip(struct of_mm_gpio_chip *mm)
52 {
53 	return container_of(mm, struct mpc8xxx_gpio_chip, mm_gc);
54 }
55 
56 static void mpc8xxx_gpio_save_regs(struct of_mm_gpio_chip *mm)
57 {
58 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
59 
60 	mpc8xxx_gc->data = in_be32(mm->regs + GPIO_DAT);
61 }
62 
63 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
64  * defined as output cannot be determined by reading GPDAT register,
65  * so we use shadow data register instead. The status of input pins
66  * is determined by reading GPDAT register.
67  */
68 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
69 {
70 	u32 val;
71 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
72 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
73 
74 	val = in_be32(mm->regs + GPIO_DAT) & ~in_be32(mm->regs + GPIO_DIR);
75 
76 	return (val | mpc8xxx_gc->data) & mpc8xxx_gpio2mask(gpio);
77 }
78 
79 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
80 {
81 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
82 
83 	return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
84 }
85 
86 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
87 {
88 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
89 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
90 	unsigned long flags;
91 
92 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
93 
94 	if (val)
95 		mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
96 	else
97 		mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
98 
99 	out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
100 
101 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
102 }
103 
104 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
105 {
106 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
107 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
108 	unsigned long flags;
109 
110 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
111 
112 	clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
113 
114 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
115 
116 	return 0;
117 }
118 
119 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
120 {
121 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
122 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
123 	unsigned long flags;
124 
125 	mpc8xxx_gpio_set(gc, gpio, val);
126 
127 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
128 
129 	setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
130 
131 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
132 
133 	return 0;
134 }
135 
136 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
137 {
138 	/* GPIO 28..31 are input only on MPC5121 */
139 	if (gpio >= 28)
140 		return -EINVAL;
141 
142 	return mpc8xxx_gpio_dir_out(gc, gpio, val);
143 }
144 
145 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
146 {
147 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
148 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
149 
150 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
151 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
152 	else
153 		return -ENXIO;
154 }
155 
156 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
157 {
158 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
159 	struct irq_chip *chip = irq_desc_get_chip(desc);
160 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
161 	unsigned int mask;
162 
163 	mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
164 	if (mask)
165 		generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
166 						     32 - ffs(mask)));
167 	if (chip->irq_eoi)
168 		chip->irq_eoi(&desc->irq_data);
169 }
170 
171 static void mpc8xxx_irq_unmask(struct irq_data *d)
172 {
173 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
174 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
175 	unsigned long flags;
176 
177 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
178 
179 	setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
180 
181 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
182 }
183 
184 static void mpc8xxx_irq_mask(struct irq_data *d)
185 {
186 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
187 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
188 	unsigned long flags;
189 
190 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
191 
192 	clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
193 
194 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
195 }
196 
197 static void mpc8xxx_irq_ack(struct irq_data *d)
198 {
199 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
200 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
201 
202 	out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
203 }
204 
205 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
206 {
207 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
208 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
209 	unsigned long flags;
210 
211 	switch (flow_type) {
212 	case IRQ_TYPE_EDGE_FALLING:
213 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
214 		setbits32(mm->regs + GPIO_ICR,
215 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
216 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
217 		break;
218 
219 	case IRQ_TYPE_EDGE_BOTH:
220 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
221 		clrbits32(mm->regs + GPIO_ICR,
222 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
223 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
224 		break;
225 
226 	default:
227 		return -EINVAL;
228 	}
229 
230 	return 0;
231 }
232 
233 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
234 {
235 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
236 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
237 	unsigned long gpio = irqd_to_hwirq(d);
238 	void __iomem *reg;
239 	unsigned int shift;
240 	unsigned long flags;
241 
242 	if (gpio < 16) {
243 		reg = mm->regs + GPIO_ICR;
244 		shift = (15 - gpio) * 2;
245 	} else {
246 		reg = mm->regs + GPIO_ICR2;
247 		shift = (15 - (gpio % 16)) * 2;
248 	}
249 
250 	switch (flow_type) {
251 	case IRQ_TYPE_EDGE_FALLING:
252 	case IRQ_TYPE_LEVEL_LOW:
253 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
254 		clrsetbits_be32(reg, 3 << shift, 2 << shift);
255 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
256 		break;
257 
258 	case IRQ_TYPE_EDGE_RISING:
259 	case IRQ_TYPE_LEVEL_HIGH:
260 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
261 		clrsetbits_be32(reg, 3 << shift, 1 << shift);
262 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
263 		break;
264 
265 	case IRQ_TYPE_EDGE_BOTH:
266 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
267 		clrbits32(reg, 3 << shift);
268 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
269 		break;
270 
271 	default:
272 		return -EINVAL;
273 	}
274 
275 	return 0;
276 }
277 
278 static struct irq_chip mpc8xxx_irq_chip = {
279 	.name		= "mpc8xxx-gpio",
280 	.irq_unmask	= mpc8xxx_irq_unmask,
281 	.irq_mask	= mpc8xxx_irq_mask,
282 	.irq_ack	= mpc8xxx_irq_ack,
283 	.irq_set_type	= mpc8xxx_irq_set_type,
284 };
285 
286 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int virq,
287 				irq_hw_number_t hw)
288 {
289 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
290 
291 	if (mpc8xxx_gc->of_dev_id_data)
292 		mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
293 
294 	irq_set_chip_data(virq, h->host_data);
295 	irq_set_chip_and_handler(virq, &mpc8xxx_irq_chip, handle_level_irq);
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