xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision 930beb5a)
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 	u32 out_mask, out_shadow;
74 
75 	out_mask = in_be32(mm->regs + GPIO_DIR);
76 
77 	val = in_be32(mm->regs + GPIO_DAT) & ~out_mask;
78 	out_shadow = mpc8xxx_gc->data & out_mask;
79 
80 	return (val | out_shadow) & mpc8xxx_gpio2mask(gpio);
81 }
82 
83 static int mpc8xxx_gpio_get(struct gpio_chip *gc, unsigned int gpio)
84 {
85 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
86 
87 	return in_be32(mm->regs + GPIO_DAT) & mpc8xxx_gpio2mask(gpio);
88 }
89 
90 static void mpc8xxx_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
91 {
92 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
93 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
94 	unsigned long flags;
95 
96 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
97 
98 	if (val)
99 		mpc8xxx_gc->data |= mpc8xxx_gpio2mask(gpio);
100 	else
101 		mpc8xxx_gc->data &= ~mpc8xxx_gpio2mask(gpio);
102 
103 	out_be32(mm->regs + GPIO_DAT, mpc8xxx_gc->data);
104 
105 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
106 }
107 
108 static int mpc8xxx_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
109 {
110 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
111 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
112 	unsigned long flags;
113 
114 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
115 
116 	clrbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
117 
118 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
119 
120 	return 0;
121 }
122 
123 static int mpc8xxx_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
124 {
125 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
126 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
127 	unsigned long flags;
128 
129 	mpc8xxx_gpio_set(gc, gpio, val);
130 
131 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
132 
133 	setbits32(mm->regs + GPIO_DIR, mpc8xxx_gpio2mask(gpio));
134 
135 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
136 
137 	return 0;
138 }
139 
140 static int mpc5121_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
141 {
142 	/* GPIO 28..31 are input only on MPC5121 */
143 	if (gpio >= 28)
144 		return -EINVAL;
145 
146 	return mpc8xxx_gpio_dir_out(gc, gpio, val);
147 }
148 
149 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
150 {
151 	struct of_mm_gpio_chip *mm = to_of_mm_gpio_chip(gc);
152 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = to_mpc8xxx_gpio_chip(mm);
153 
154 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
155 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
156 	else
157 		return -ENXIO;
158 }
159 
160 static void mpc8xxx_gpio_irq_cascade(unsigned int irq, struct irq_desc *desc)
161 {
162 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
163 	struct irq_chip *chip = irq_desc_get_chip(desc);
164 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
165 	unsigned int mask;
166 
167 	mask = in_be32(mm->regs + GPIO_IER) & in_be32(mm->regs + GPIO_IMR);
168 	if (mask)
169 		generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
170 						     32 - ffs(mask)));
171 	if (chip->irq_eoi)
172 		chip->irq_eoi(&desc->irq_data);
173 }
174 
175 static void mpc8xxx_irq_unmask(struct irq_data *d)
176 {
177 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
178 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
179 	unsigned long flags;
180 
181 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
182 
183 	setbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
184 
185 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
186 }
187 
188 static void mpc8xxx_irq_mask(struct irq_data *d)
189 {
190 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
191 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
192 	unsigned long flags;
193 
194 	spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
195 
196 	clrbits32(mm->regs + GPIO_IMR, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
197 
198 	spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
199 }
200 
201 static void mpc8xxx_irq_ack(struct irq_data *d)
202 {
203 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
204 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
205 
206 	out_be32(mm->regs + GPIO_IER, mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
207 }
208 
209 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
210 {
211 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
212 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
213 	unsigned long flags;
214 
215 	switch (flow_type) {
216 	case IRQ_TYPE_EDGE_FALLING:
217 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
218 		setbits32(mm->regs + GPIO_ICR,
219 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
220 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
221 		break;
222 
223 	case IRQ_TYPE_EDGE_BOTH:
224 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
225 		clrbits32(mm->regs + GPIO_ICR,
226 			  mpc8xxx_gpio2mask(irqd_to_hwirq(d)));
227 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
228 		break;
229 
230 	default:
231 		return -EINVAL;
232 	}
233 
234 	return 0;
235 }
236 
237 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
238 {
239 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
240 	struct of_mm_gpio_chip *mm = &mpc8xxx_gc->mm_gc;
241 	unsigned long gpio = irqd_to_hwirq(d);
242 	void __iomem *reg;
243 	unsigned int shift;
244 	unsigned long flags;
245 
246 	if (gpio < 16) {
247 		reg = mm->regs + GPIO_ICR;
248 		shift = (15 - gpio) * 2;
249 	} else {
250 		reg = mm->regs + GPIO_ICR2;
251 		shift = (15 - (gpio % 16)) * 2;
252 	}
253 
254 	switch (flow_type) {
255 	case IRQ_TYPE_EDGE_FALLING:
256 	case IRQ_TYPE_LEVEL_LOW:
257 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
258 		clrsetbits_be32(reg, 3 << shift, 2 << shift);
259 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
260 		break;
261 
262 	case IRQ_TYPE_EDGE_RISING:
263 	case IRQ_TYPE_LEVEL_HIGH:
264 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
265 		clrsetbits_be32(reg, 3 << shift, 1 << shift);
266 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
267 		break;
268 
269 	case IRQ_TYPE_EDGE_BOTH:
270 		spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
271 		clrbits32(reg, 3 << shift);
272 		spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
273 		break;
274 
275 	default:
276 		return -EINVAL;
277 	}
278 
279 	return 0;
280 }
281 
282 static struct irq_chip mpc8xxx_irq_chip = {
283 	.name		= "mpc8xxx-gpio",
284 	.irq_unmask	= mpc8xxx_irq_unmask,
285 	.irq_mask	= mpc8xxx_irq_mask,
286 	.irq_ack	= mpc8xxx_irq_ack,
287 	.irq_set_type	= mpc8xxx_irq_set_type,
288 };
289 
290 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
291 				irq_hw_number_t hwirq)
292 {
293 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = h->host_data;
294 
295 	if (mpc8xxx_gc->of_dev_id_data)
296 		mpc8xxx_irq_chip.irq_set_type = mpc8xxx_gc->of_dev_id_data;
297 
298 	irq_set_chip_data(irq, h->host_data);
299 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_level_irq);
300 
301 	return 0;
302 }
303 
304 static struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
305 	.map	= mpc8xxx_gpio_irq_map,
306 	.xlate	= irq_domain_xlate_twocell,
307 };
308 
309 static struct of_device_id mpc8xxx_gpio_ids[] __initdata = {
310 	{ .compatible = "fsl,mpc8349-gpio", },
311 	{ .compatible = "fsl,mpc8572-gpio", },
312 	{ .compatible = "fsl,mpc8610-gpio", },
313 	{ .compatible = "fsl,mpc5121-gpio", .data = mpc512x_irq_set_type, },
314 	{ .compatible = "fsl,pq3-gpio",     },
315 	{ .compatible = "fsl,qoriq-gpio",   },
316 	{}
317 };
318 
319 static void __init mpc8xxx_add_controller(struct device_node *np)
320 {
321 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
322 	struct of_mm_gpio_chip *mm_gc;
323 	struct gpio_chip *gc;
324 	const struct of_device_id *id;
325 	unsigned hwirq;
326 	int ret;
327 
328 	mpc8xxx_gc = kzalloc(sizeof(*mpc8xxx_gc), GFP_KERNEL);
329 	if (!mpc8xxx_gc) {
330 		ret = -ENOMEM;
331 		goto err;
332 	}
333 
334 	spin_lock_init(&mpc8xxx_gc->lock);
335 
336 	mm_gc = &mpc8xxx_gc->mm_gc;
337 	gc = &mm_gc->gc;
338 
339 	mm_gc->save_regs = mpc8xxx_gpio_save_regs;
340 	gc->ngpio = MPC8XXX_GPIO_PINS;
341 	gc->direction_input = mpc8xxx_gpio_dir_in;
342 	gc->direction_output = of_device_is_compatible(np, "fsl,mpc5121-gpio") ?
343 		mpc5121_gpio_dir_out : mpc8xxx_gpio_dir_out;
344 	gc->get = of_device_is_compatible(np, "fsl,mpc8572-gpio") ?
345 		mpc8572_gpio_get : mpc8xxx_gpio_get;
346 	gc->set = mpc8xxx_gpio_set;
347 	gc->to_irq = mpc8xxx_gpio_to_irq;
348 
349 	ret = of_mm_gpiochip_add(np, mm_gc);
350 	if (ret)
351 		goto err;
352 
353 	hwirq = irq_of_parse_and_map(np, 0);
354 	if (hwirq == NO_IRQ)
355 		goto skip_irq;
356 
357 	mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
358 					&mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
359 	if (!mpc8xxx_gc->irq)
360 		goto skip_irq;
361 
362 	id = of_match_node(mpc8xxx_gpio_ids, np);
363 	if (id)
364 		mpc8xxx_gc->of_dev_id_data = id->data;
365 
366 	/* ack and mask all irqs */
367 	out_be32(mm_gc->regs + GPIO_IER, 0xffffffff);
368 	out_be32(mm_gc->regs + GPIO_IMR, 0);
369 
370 	irq_set_handler_data(hwirq, mpc8xxx_gc);
371 	irq_set_chained_handler(hwirq, mpc8xxx_gpio_irq_cascade);
372 
373 skip_irq:
374 	return;
375 
376 err:
377 	pr_err("%s: registration failed with status %d\n",
378 	       np->full_name, ret);
379 	kfree(mpc8xxx_gc);
380 
381 	return;
382 }
383 
384 static int __init mpc8xxx_add_gpiochips(void)
385 {
386 	struct device_node *np;
387 
388 	for_each_matching_node(np, mpc8xxx_gpio_ids)
389 		mpc8xxx_add_controller(np);
390 
391 	return 0;
392 }
393 arch_initcall(mpc8xxx_add_gpiochips);
394