xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision 0edbfea5)
1 /*
2  * GPIOs on MPC512x/8349/8572/8610/QorIQ and compatible
3  *
4  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
5  * Copyright (C) 2016 Freescale Semiconductor Inc.
6  *
7  * This file is licensed under the terms of the GNU General Public License
8  * version 2.  This program is licensed "as is" without any warranty of any
9  * kind, whether express or implied.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/spinlock.h>
15 #include <linux/io.h>
16 #include <linux/of.h>
17 #include <linux/of_gpio.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_platform.h>
21 #include <linux/slab.h>
22 #include <linux/irq.h>
23 #include <linux/gpio/driver.h>
24 
25 #define MPC8XXX_GPIO_PINS	32
26 
27 #define GPIO_DIR		0x00
28 #define GPIO_ODR		0x04
29 #define GPIO_DAT		0x08
30 #define GPIO_IER		0x0c
31 #define GPIO_IMR		0x10
32 #define GPIO_ICR		0x14
33 #define GPIO_ICR2		0x18
34 
35 struct mpc8xxx_gpio_chip {
36 	struct gpio_chip	gc;
37 	void __iomem *regs;
38 	raw_spinlock_t lock;
39 
40 	int (*direction_output)(struct gpio_chip *chip,
41 				unsigned offset, int value);
42 
43 	struct irq_domain *irq;
44 	unsigned int irqn;
45 };
46 
47 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
48  * defined as output cannot be determined by reading GPDAT register,
49  * so we use shadow data register instead. The status of input pins
50  * is determined by reading GPDAT register.
51  */
52 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
53 {
54 	u32 val;
55 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
56 	u32 out_mask, out_shadow;
57 
58 	out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
59 	val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
60 	out_shadow = gc->bgpio_data & out_mask;
61 
62 	return !!((val | out_shadow) & gc->pin2mask(gc, gpio));
63 }
64 
65 static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
66 				unsigned int gpio, int val)
67 {
68 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
69 	/* GPIO 28..31 are input only on MPC5121 */
70 	if (gpio >= 28)
71 		return -EINVAL;
72 
73 	return mpc8xxx_gc->direction_output(gc, gpio, val);
74 }
75 
76 static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
77 				unsigned int gpio, int val)
78 {
79 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
80 	/* GPIO 0..3 are input only on MPC5125 */
81 	if (gpio <= 3)
82 		return -EINVAL;
83 
84 	return mpc8xxx_gc->direction_output(gc, gpio, val);
85 }
86 
87 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
88 {
89 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
90 
91 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
92 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
93 	else
94 		return -ENXIO;
95 }
96 
97 static void mpc8xxx_gpio_irq_cascade(struct irq_desc *desc)
98 {
99 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc);
100 	struct irq_chip *chip = irq_desc_get_chip(desc);
101 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
102 	unsigned int mask;
103 
104 	mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
105 		& gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
106 	if (mask)
107 		generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq,
108 						     32 - ffs(mask)));
109 	if (chip->irq_eoi)
110 		chip->irq_eoi(&desc->irq_data);
111 }
112 
113 static void mpc8xxx_irq_unmask(struct irq_data *d)
114 {
115 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
116 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
117 	unsigned long flags;
118 
119 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
120 
121 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
122 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
123 		| gc->pin2mask(gc, irqd_to_hwirq(d)));
124 
125 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
126 }
127 
128 static void mpc8xxx_irq_mask(struct irq_data *d)
129 {
130 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
131 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
132 	unsigned long flags;
133 
134 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
135 
136 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
137 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
138 		& ~(gc->pin2mask(gc, irqd_to_hwirq(d))));
139 
140 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
141 }
142 
143 static void mpc8xxx_irq_ack(struct irq_data *d)
144 {
145 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
146 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
147 
148 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
149 		      gc->pin2mask(gc, irqd_to_hwirq(d)));
150 }
151 
152 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
153 {
154 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
155 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
156 	unsigned long flags;
157 
158 	switch (flow_type) {
159 	case IRQ_TYPE_EDGE_FALLING:
160 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
161 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
162 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
163 			| gc->pin2mask(gc, irqd_to_hwirq(d)));
164 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
165 		break;
166 
167 	case IRQ_TYPE_EDGE_BOTH:
168 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
169 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
170 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
171 			& ~(gc->pin2mask(gc, irqd_to_hwirq(d))));
172 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
173 		break;
174 
175 	default:
176 		return -EINVAL;
177 	}
178 
179 	return 0;
180 }
181 
182 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
183 {
184 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
185 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
186 	unsigned long gpio = irqd_to_hwirq(d);
187 	void __iomem *reg;
188 	unsigned int shift;
189 	unsigned long flags;
190 
191 	if (gpio < 16) {
192 		reg = mpc8xxx_gc->regs + GPIO_ICR;
193 		shift = (15 - gpio) * 2;
194 	} else {
195 		reg = mpc8xxx_gc->regs + GPIO_ICR2;
196 		shift = (15 - (gpio % 16)) * 2;
197 	}
198 
199 	switch (flow_type) {
200 	case IRQ_TYPE_EDGE_FALLING:
201 	case IRQ_TYPE_LEVEL_LOW:
202 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
203 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
204 			| (2 << shift));
205 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
206 		break;
207 
208 	case IRQ_TYPE_EDGE_RISING:
209 	case IRQ_TYPE_LEVEL_HIGH:
210 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
211 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
212 			| (1 << shift));
213 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
214 		break;
215 
216 	case IRQ_TYPE_EDGE_BOTH:
217 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
218 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
219 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
220 		break;
221 
222 	default:
223 		return -EINVAL;
224 	}
225 
226 	return 0;
227 }
228 
229 static struct irq_chip mpc8xxx_irq_chip = {
230 	.name		= "mpc8xxx-gpio",
231 	.irq_unmask	= mpc8xxx_irq_unmask,
232 	.irq_mask	= mpc8xxx_irq_mask,
233 	.irq_ack	= mpc8xxx_irq_ack,
234 	/* this might get overwritten in mpc8xxx_probe() */
235 	.irq_set_type	= mpc8xxx_irq_set_type,
236 };
237 
238 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
239 				irq_hw_number_t hwirq)
240 {
241 	irq_set_chip_data(irq, h->host_data);
242 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_level_irq);
243 
244 	return 0;
245 }
246 
247 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
248 	.map	= mpc8xxx_gpio_irq_map,
249 	.xlate	= irq_domain_xlate_twocell,
250 };
251 
252 struct mpc8xxx_gpio_devtype {
253 	int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
254 	int (*gpio_get)(struct gpio_chip *, unsigned int);
255 	int (*irq_set_type)(struct irq_data *, unsigned int);
256 };
257 
258 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
259 	.gpio_dir_out = mpc5121_gpio_dir_out,
260 	.irq_set_type = mpc512x_irq_set_type,
261 };
262 
263 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
264 	.gpio_dir_out = mpc5125_gpio_dir_out,
265 	.irq_set_type = mpc512x_irq_set_type,
266 };
267 
268 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
269 	.gpio_get = mpc8572_gpio_get,
270 };
271 
272 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
273 	.irq_set_type = mpc8xxx_irq_set_type,
274 };
275 
276 static const struct of_device_id mpc8xxx_gpio_ids[] = {
277 	{ .compatible = "fsl,mpc8349-gpio", },
278 	{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
279 	{ .compatible = "fsl,mpc8610-gpio", },
280 	{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
281 	{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
282 	{ .compatible = "fsl,pq3-gpio",     },
283 	{ .compatible = "fsl,qoriq-gpio",   },
284 	{}
285 };
286 
287 static int mpc8xxx_probe(struct platform_device *pdev)
288 {
289 	struct device_node *np = pdev->dev.of_node;
290 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
291 	struct gpio_chip	*gc;
292 	const struct mpc8xxx_gpio_devtype *devtype =
293 		of_device_get_match_data(&pdev->dev);
294 	int ret;
295 
296 	mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
297 	if (!mpc8xxx_gc)
298 		return -ENOMEM;
299 
300 	platform_set_drvdata(pdev, mpc8xxx_gc);
301 
302 	raw_spin_lock_init(&mpc8xxx_gc->lock);
303 
304 	mpc8xxx_gc->regs = of_iomap(np, 0);
305 	if (!mpc8xxx_gc->regs)
306 		return -ENOMEM;
307 
308 	gc = &mpc8xxx_gc->gc;
309 
310 	if (of_property_read_bool(np, "little-endian")) {
311 		ret = bgpio_init(gc, &pdev->dev, 4,
312 				 mpc8xxx_gc->regs + GPIO_DAT,
313 				 NULL, NULL,
314 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
315 				 BGPIOF_BIG_ENDIAN);
316 		if (ret)
317 			goto err;
318 		dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
319 	} else {
320 		ret = bgpio_init(gc, &pdev->dev, 4,
321 				 mpc8xxx_gc->regs + GPIO_DAT,
322 				 NULL, NULL,
323 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
324 				 BGPIOF_BIG_ENDIAN
325 				 | BGPIOF_BIG_ENDIAN_BYTE_ORDER);
326 		if (ret)
327 			goto err;
328 		dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
329 	}
330 
331 	mpc8xxx_gc->direction_output = gc->direction_output;
332 
333 	if (!devtype)
334 		devtype = &mpc8xxx_gpio_devtype_default;
335 
336 	/*
337 	 * It's assumed that only a single type of gpio controller is available
338 	 * on the current machine, so overwriting global data is fine.
339 	 */
340 	mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
341 
342 	if (devtype->gpio_dir_out)
343 		gc->direction_output = devtype->gpio_dir_out;
344 	if (devtype->gpio_get)
345 		gc->get = devtype->gpio_get;
346 
347 	gc->to_irq = mpc8xxx_gpio_to_irq;
348 
349 	ret = gpiochip_add_data(gc, mpc8xxx_gc);
350 	if (ret) {
351 		pr_err("%s: GPIO chip registration failed with status %d\n",
352 		       np->full_name, ret);
353 		goto err;
354 	}
355 
356 	mpc8xxx_gc->irqn = irq_of_parse_and_map(np, 0);
357 	if (!mpc8xxx_gc->irqn)
358 		return 0;
359 
360 	mpc8xxx_gc->irq = irq_domain_add_linear(np, MPC8XXX_GPIO_PINS,
361 					&mpc8xxx_gpio_irq_ops, mpc8xxx_gc);
362 	if (!mpc8xxx_gc->irq)
363 		return 0;
364 
365 	/* ack and mask all irqs */
366 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
367 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
368 
369 	irq_set_chained_handler_and_data(mpc8xxx_gc->irqn,
370 					 mpc8xxx_gpio_irq_cascade, mpc8xxx_gc);
371 	return 0;
372 err:
373 	iounmap(mpc8xxx_gc->regs);
374 	return ret;
375 }
376 
377 static int mpc8xxx_remove(struct platform_device *pdev)
378 {
379 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
380 
381 	if (mpc8xxx_gc->irq) {
382 		irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
383 		irq_domain_remove(mpc8xxx_gc->irq);
384 	}
385 
386 	gpiochip_remove(&mpc8xxx_gc->gc);
387 	iounmap(mpc8xxx_gc->regs);
388 
389 	return 0;
390 }
391 
392 static struct platform_driver mpc8xxx_plat_driver = {
393 	.probe		= mpc8xxx_probe,
394 	.remove		= mpc8xxx_remove,
395 	.driver		= {
396 		.name = "gpio-mpc8xxx",
397 		.of_match_table	= mpc8xxx_gpio_ids,
398 	},
399 };
400 
401 static int __init mpc8xxx_init(void)
402 {
403 	return platform_driver_register(&mpc8xxx_plat_driver);
404 }
405 
406 arch_initcall(mpc8xxx_init);
407