xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision 829c6524)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GPIOs on MPC512x/8349/8572/8610/QorIQ and compatible
4  *
5  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
6  * Copyright (C) 2016 Freescale Semiconductor Inc.
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/io.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17 #include <linux/of_platform.h>
18 #include <linux/property.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/slab.h>
21 #include <linux/irq.h>
22 #include <linux/gpio/driver.h>
23 #include <linux/bitops.h>
24 #include <linux/interrupt.h>
25 
26 #define MPC8XXX_GPIO_PINS	32
27 
28 #define GPIO_DIR		0x00
29 #define GPIO_ODR		0x04
30 #define GPIO_DAT		0x08
31 #define GPIO_IER		0x0c
32 #define GPIO_IMR		0x10
33 #define GPIO_ICR		0x14
34 #define GPIO_ICR2		0x18
35 #define GPIO_IBE		0x18
36 
37 struct mpc8xxx_gpio_chip {
38 	struct gpio_chip	gc;
39 	void __iomem *regs;
40 	raw_spinlock_t lock;
41 
42 	int (*direction_output)(struct gpio_chip *chip,
43 				unsigned offset, int value);
44 
45 	struct irq_domain *irq;
46 	int irqn;
47 };
48 
49 /*
50  * This hardware has a big endian bit assignment such that GPIO line 0 is
51  * connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
52  * This inline helper give the right bitmask for a certain line.
53  */
54 static inline u32 mpc_pin2mask(unsigned int offset)
55 {
56 	return BIT(31 - offset);
57 }
58 
59 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
60  * defined as output cannot be determined by reading GPDAT register,
61  * so we use shadow data register instead. The status of input pins
62  * is determined by reading GPDAT register.
63  */
64 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
65 {
66 	u32 val;
67 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
68 	u32 out_mask, out_shadow;
69 
70 	out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
71 	val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
72 	out_shadow = gc->bgpio_data & out_mask;
73 
74 	return !!((val | out_shadow) & mpc_pin2mask(gpio));
75 }
76 
77 static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
78 				unsigned int gpio, int val)
79 {
80 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
81 	/* GPIO 28..31 are input only on MPC5121 */
82 	if (gpio >= 28)
83 		return -EINVAL;
84 
85 	return mpc8xxx_gc->direction_output(gc, gpio, val);
86 }
87 
88 static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
89 				unsigned int gpio, int val)
90 {
91 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
92 	/* GPIO 0..3 are input only on MPC5125 */
93 	if (gpio <= 3)
94 		return -EINVAL;
95 
96 	return mpc8xxx_gc->direction_output(gc, gpio, val);
97 }
98 
99 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
100 {
101 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
102 
103 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
104 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
105 	else
106 		return -ENXIO;
107 }
108 
109 static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data)
110 {
111 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = data;
112 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
113 	unsigned long mask;
114 	int i;
115 
116 	mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
117 		& gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
118 	for_each_set_bit(i, &mask, 32)
119 		generic_handle_domain_irq(mpc8xxx_gc->irq, 31 - i);
120 
121 	return IRQ_HANDLED;
122 }
123 
124 static void mpc8xxx_irq_unmask(struct irq_data *d)
125 {
126 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
127 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
128 	unsigned long flags;
129 
130 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
131 
132 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
133 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
134 		| mpc_pin2mask(irqd_to_hwirq(d)));
135 
136 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
137 }
138 
139 static void mpc8xxx_irq_mask(struct irq_data *d)
140 {
141 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
142 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
143 	unsigned long flags;
144 
145 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
146 
147 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
148 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
149 		& ~mpc_pin2mask(irqd_to_hwirq(d)));
150 
151 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
152 }
153 
154 static void mpc8xxx_irq_ack(struct irq_data *d)
155 {
156 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
157 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
158 
159 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
160 		      mpc_pin2mask(irqd_to_hwirq(d)));
161 }
162 
163 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
164 {
165 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
166 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
167 	unsigned long flags;
168 
169 	switch (flow_type) {
170 	case IRQ_TYPE_EDGE_FALLING:
171 	case IRQ_TYPE_LEVEL_LOW:
172 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
173 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
174 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
175 			| mpc_pin2mask(irqd_to_hwirq(d)));
176 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
177 		break;
178 
179 	case IRQ_TYPE_EDGE_BOTH:
180 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
181 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
182 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
183 			& ~mpc_pin2mask(irqd_to_hwirq(d)));
184 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
185 		break;
186 
187 	default:
188 		return -EINVAL;
189 	}
190 
191 	return 0;
192 }
193 
194 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
195 {
196 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
197 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
198 	unsigned long gpio = irqd_to_hwirq(d);
199 	void __iomem *reg;
200 	unsigned int shift;
201 	unsigned long flags;
202 
203 	if (gpio < 16) {
204 		reg = mpc8xxx_gc->regs + GPIO_ICR;
205 		shift = (15 - gpio) * 2;
206 	} else {
207 		reg = mpc8xxx_gc->regs + GPIO_ICR2;
208 		shift = (15 - (gpio % 16)) * 2;
209 	}
210 
211 	switch (flow_type) {
212 	case IRQ_TYPE_EDGE_FALLING:
213 	case IRQ_TYPE_LEVEL_LOW:
214 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
215 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
216 			| (2 << shift));
217 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
218 		break;
219 
220 	case IRQ_TYPE_EDGE_RISING:
221 	case IRQ_TYPE_LEVEL_HIGH:
222 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
223 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
224 			| (1 << shift));
225 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
226 		break;
227 
228 	case IRQ_TYPE_EDGE_BOTH:
229 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
230 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
231 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
232 		break;
233 
234 	default:
235 		return -EINVAL;
236 	}
237 
238 	return 0;
239 }
240 
241 static struct irq_chip mpc8xxx_irq_chip = {
242 	.name		= "mpc8xxx-gpio",
243 	.irq_unmask	= mpc8xxx_irq_unmask,
244 	.irq_mask	= mpc8xxx_irq_mask,
245 	.irq_ack	= mpc8xxx_irq_ack,
246 	/* this might get overwritten in mpc8xxx_probe() */
247 	.irq_set_type	= mpc8xxx_irq_set_type,
248 };
249 
250 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
251 				irq_hw_number_t hwirq)
252 {
253 	irq_set_chip_data(irq, h->host_data);
254 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_edge_irq);
255 
256 	return 0;
257 }
258 
259 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
260 	.map	= mpc8xxx_gpio_irq_map,
261 	.xlate	= irq_domain_xlate_twocell,
262 };
263 
264 struct mpc8xxx_gpio_devtype {
265 	int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
266 	int (*gpio_get)(struct gpio_chip *, unsigned int);
267 	int (*irq_set_type)(struct irq_data *, unsigned int);
268 };
269 
270 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
271 	.gpio_dir_out = mpc5121_gpio_dir_out,
272 	.irq_set_type = mpc512x_irq_set_type,
273 };
274 
275 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
276 	.gpio_dir_out = mpc5125_gpio_dir_out,
277 	.irq_set_type = mpc512x_irq_set_type,
278 };
279 
280 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
281 	.gpio_get = mpc8572_gpio_get,
282 };
283 
284 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
285 	.irq_set_type = mpc8xxx_irq_set_type,
286 };
287 
288 static const struct of_device_id mpc8xxx_gpio_ids[] = {
289 	{ .compatible = "fsl,mpc8349-gpio", },
290 	{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
291 	{ .compatible = "fsl,mpc8610-gpio", },
292 	{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
293 	{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
294 	{ .compatible = "fsl,pq3-gpio",     },
295 	{ .compatible = "fsl,ls1028a-gpio", },
296 	{ .compatible = "fsl,ls1088a-gpio", },
297 	{ .compatible = "fsl,qoriq-gpio",   },
298 	{}
299 };
300 
301 static int mpc8xxx_probe(struct platform_device *pdev)
302 {
303 	struct device_node *np = pdev->dev.of_node;
304 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
305 	struct gpio_chip	*gc;
306 	const struct mpc8xxx_gpio_devtype *devtype = NULL;
307 	struct fwnode_handle *fwnode;
308 	int ret;
309 
310 	mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
311 	if (!mpc8xxx_gc)
312 		return -ENOMEM;
313 
314 	platform_set_drvdata(pdev, mpc8xxx_gc);
315 
316 	raw_spin_lock_init(&mpc8xxx_gc->lock);
317 
318 	mpc8xxx_gc->regs = devm_platform_ioremap_resource(pdev, 0);
319 	if (IS_ERR(mpc8xxx_gc->regs))
320 		return PTR_ERR(mpc8xxx_gc->regs);
321 
322 	gc = &mpc8xxx_gc->gc;
323 	gc->parent = &pdev->dev;
324 
325 	if (device_property_read_bool(&pdev->dev, "little-endian")) {
326 		ret = bgpio_init(gc, &pdev->dev, 4,
327 				 mpc8xxx_gc->regs + GPIO_DAT,
328 				 NULL, NULL,
329 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
330 				 BGPIOF_BIG_ENDIAN);
331 		if (ret)
332 			return ret;
333 		dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
334 	} else {
335 		ret = bgpio_init(gc, &pdev->dev, 4,
336 				 mpc8xxx_gc->regs + GPIO_DAT,
337 				 NULL, NULL,
338 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
339 				 BGPIOF_BIG_ENDIAN
340 				 | BGPIOF_BIG_ENDIAN_BYTE_ORDER);
341 		if (ret)
342 			return ret;
343 		dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
344 	}
345 
346 	mpc8xxx_gc->direction_output = gc->direction_output;
347 
348 	devtype = device_get_match_data(&pdev->dev);
349 	if (!devtype)
350 		devtype = &mpc8xxx_gpio_devtype_default;
351 
352 	/*
353 	 * It's assumed that only a single type of gpio controller is available
354 	 * on the current machine, so overwriting global data is fine.
355 	 */
356 	if (devtype->irq_set_type)
357 		mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
358 
359 	if (devtype->gpio_dir_out)
360 		gc->direction_output = devtype->gpio_dir_out;
361 	if (devtype->gpio_get)
362 		gc->get = devtype->gpio_get;
363 
364 	gc->to_irq = mpc8xxx_gpio_to_irq;
365 
366 	/*
367 	 * The GPIO Input Buffer Enable register(GPIO_IBE) is used to control
368 	 * the input enable of each individual GPIO port.  When an individual
369 	 * GPIO port’s direction is set to input (GPIO_GPDIR[DRn=0]), the
370 	 * associated input enable must be set (GPIOxGPIE[IEn]=1) to propagate
371 	 * the port value to the GPIO Data Register.
372 	 */
373 	fwnode = dev_fwnode(&pdev->dev);
374 	if (of_device_is_compatible(np, "fsl,qoriq-gpio") ||
375 	    of_device_is_compatible(np, "fsl,ls1028a-gpio") ||
376 	    of_device_is_compatible(np, "fsl,ls1088a-gpio") ||
377 	    is_acpi_node(fwnode)) {
378 		gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
379 		/* Also, latch state of GPIOs configured as output by bootloader. */
380 		gc->bgpio_data = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) &
381 			gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
382 	}
383 
384 	ret = devm_gpiochip_add_data(&pdev->dev, gc, mpc8xxx_gc);
385 	if (ret) {
386 		dev_err(&pdev->dev,
387 			"GPIO chip registration failed with status %d\n", ret);
388 		return ret;
389 	}
390 
391 	mpc8xxx_gc->irqn = platform_get_irq(pdev, 0);
392 	if (mpc8xxx_gc->irqn < 0)
393 		return mpc8xxx_gc->irqn;
394 
395 	mpc8xxx_gc->irq = irq_domain_create_linear(fwnode,
396 						   MPC8XXX_GPIO_PINS,
397 						   &mpc8xxx_gpio_irq_ops,
398 						   mpc8xxx_gc);
399 
400 	if (!mpc8xxx_gc->irq)
401 		return 0;
402 
403 	/* ack and mask all irqs */
404 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
405 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
406 
407 	ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn,
408 			       mpc8xxx_gpio_irq_cascade,
409 			       IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade",
410 			       mpc8xxx_gc);
411 	if (ret) {
412 		dev_err(&pdev->dev,
413 			"failed to devm_request_irq(%d), ret = %d\n",
414 			mpc8xxx_gc->irqn, ret);
415 		goto err;
416 	}
417 
418 	return 0;
419 err:
420 	irq_domain_remove(mpc8xxx_gc->irq);
421 	return ret;
422 }
423 
424 static int mpc8xxx_remove(struct platform_device *pdev)
425 {
426 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
427 
428 	if (mpc8xxx_gc->irq) {
429 		irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
430 		irq_domain_remove(mpc8xxx_gc->irq);
431 	}
432 
433 	return 0;
434 }
435 
436 #ifdef CONFIG_ACPI
437 static const struct acpi_device_id gpio_acpi_ids[] = {
438 	{"NXP0031",},
439 	{ }
440 };
441 MODULE_DEVICE_TABLE(acpi, gpio_acpi_ids);
442 #endif
443 
444 static struct platform_driver mpc8xxx_plat_driver = {
445 	.probe		= mpc8xxx_probe,
446 	.remove		= mpc8xxx_remove,
447 	.driver		= {
448 		.name = "gpio-mpc8xxx",
449 		.of_match_table	= mpc8xxx_gpio_ids,
450 		.acpi_match_table = ACPI_PTR(gpio_acpi_ids),
451 	},
452 };
453 
454 static int __init mpc8xxx_init(void)
455 {
456 	return platform_driver_register(&mpc8xxx_plat_driver);
457 }
458 
459 arch_initcall(mpc8xxx_init);
460