xref: /openbmc/linux/drivers/gpio/gpio-mpc8xxx.c (revision 2cf1c348)
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/acpi.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/io.h>
17 #include <linux/of.h>
18 #include <linux/of_gpio.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_platform.h>
22 #include <linux/property.h>
23 #include <linux/mod_devicetable.h>
24 #include <linux/slab.h>
25 #include <linux/irq.h>
26 #include <linux/gpio/driver.h>
27 #include <linux/bitops.h>
28 #include <linux/interrupt.h>
29 
30 #define MPC8XXX_GPIO_PINS	32
31 
32 #define GPIO_DIR		0x00
33 #define GPIO_ODR		0x04
34 #define GPIO_DAT		0x08
35 #define GPIO_IER		0x0c
36 #define GPIO_IMR		0x10
37 #define GPIO_ICR		0x14
38 #define GPIO_ICR2		0x18
39 #define GPIO_IBE		0x18
40 
41 struct mpc8xxx_gpio_chip {
42 	struct gpio_chip	gc;
43 	void __iomem *regs;
44 	raw_spinlock_t lock;
45 
46 	int (*direction_output)(struct gpio_chip *chip,
47 				unsigned offset, int value);
48 
49 	struct irq_domain *irq;
50 	int irqn;
51 };
52 
53 /*
54  * This hardware has a big endian bit assignment such that GPIO line 0 is
55  * connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
56  * This inline helper give the right bitmask for a certain line.
57  */
58 static inline u32 mpc_pin2mask(unsigned int offset)
59 {
60 	return BIT(31 - offset);
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 mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
72 	u32 out_mask, out_shadow;
73 
74 	out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
75 	val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
76 	out_shadow = gc->bgpio_data & out_mask;
77 
78 	return !!((val | out_shadow) & mpc_pin2mask(gpio));
79 }
80 
81 static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
82 				unsigned int gpio, int val)
83 {
84 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
85 	/* GPIO 28..31 are input only on MPC5121 */
86 	if (gpio >= 28)
87 		return -EINVAL;
88 
89 	return mpc8xxx_gc->direction_output(gc, gpio, val);
90 }
91 
92 static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
93 				unsigned int gpio, int val)
94 {
95 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
96 	/* GPIO 0..3 are input only on MPC5125 */
97 	if (gpio <= 3)
98 		return -EINVAL;
99 
100 	return mpc8xxx_gc->direction_output(gc, gpio, val);
101 }
102 
103 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
104 {
105 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
106 
107 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
108 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
109 	else
110 		return -ENXIO;
111 }
112 
113 static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data)
114 {
115 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = data;
116 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
117 	unsigned long mask;
118 	int i;
119 
120 	mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
121 		& gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
122 	for_each_set_bit(i, &mask, 32)
123 		generic_handle_domain_irq(mpc8xxx_gc->irq, 31 - i);
124 
125 	return IRQ_HANDLED;
126 }
127 
128 static void mpc8xxx_irq_unmask(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 		| mpc_pin2mask(irqd_to_hwirq(d)));
139 
140 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
141 }
142 
143 static void mpc8xxx_irq_mask(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 	unsigned long flags;
148 
149 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
150 
151 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
152 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
153 		& ~mpc_pin2mask(irqd_to_hwirq(d)));
154 
155 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
156 }
157 
158 static void mpc8xxx_irq_ack(struct irq_data *d)
159 {
160 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
161 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
162 
163 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
164 		      mpc_pin2mask(irqd_to_hwirq(d)));
165 }
166 
167 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
168 {
169 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
170 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
171 	unsigned long flags;
172 
173 	switch (flow_type) {
174 	case IRQ_TYPE_EDGE_FALLING:
175 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
176 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
177 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
178 			| mpc_pin2mask(irqd_to_hwirq(d)));
179 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
180 		break;
181 
182 	case IRQ_TYPE_EDGE_BOTH:
183 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
184 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
185 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
186 			& ~mpc_pin2mask(irqd_to_hwirq(d)));
187 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
188 		break;
189 
190 	default:
191 		return -EINVAL;
192 	}
193 
194 	return 0;
195 }
196 
197 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
198 {
199 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
200 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
201 	unsigned long gpio = irqd_to_hwirq(d);
202 	void __iomem *reg;
203 	unsigned int shift;
204 	unsigned long flags;
205 
206 	if (gpio < 16) {
207 		reg = mpc8xxx_gc->regs + GPIO_ICR;
208 		shift = (15 - gpio) * 2;
209 	} else {
210 		reg = mpc8xxx_gc->regs + GPIO_ICR2;
211 		shift = (15 - (gpio % 16)) * 2;
212 	}
213 
214 	switch (flow_type) {
215 	case IRQ_TYPE_EDGE_FALLING:
216 	case IRQ_TYPE_LEVEL_LOW:
217 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
218 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
219 			| (2 << shift));
220 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
221 		break;
222 
223 	case IRQ_TYPE_EDGE_RISING:
224 	case IRQ_TYPE_LEVEL_HIGH:
225 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
226 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
227 			| (1 << shift));
228 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
229 		break;
230 
231 	case IRQ_TYPE_EDGE_BOTH:
232 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
233 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
234 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
235 		break;
236 
237 	default:
238 		return -EINVAL;
239 	}
240 
241 	return 0;
242 }
243 
244 static struct irq_chip mpc8xxx_irq_chip = {
245 	.name		= "mpc8xxx-gpio",
246 	.irq_unmask	= mpc8xxx_irq_unmask,
247 	.irq_mask	= mpc8xxx_irq_mask,
248 	.irq_ack	= mpc8xxx_irq_ack,
249 	/* this might get overwritten in mpc8xxx_probe() */
250 	.irq_set_type	= mpc8xxx_irq_set_type,
251 };
252 
253 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
254 				irq_hw_number_t hwirq)
255 {
256 	irq_set_chip_data(irq, h->host_data);
257 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_edge_irq);
258 
259 	return 0;
260 }
261 
262 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
263 	.map	= mpc8xxx_gpio_irq_map,
264 	.xlate	= irq_domain_xlate_twocell,
265 };
266 
267 struct mpc8xxx_gpio_devtype {
268 	int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
269 	int (*gpio_get)(struct gpio_chip *, unsigned int);
270 	int (*irq_set_type)(struct irq_data *, unsigned int);
271 };
272 
273 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
274 	.gpio_dir_out = mpc5121_gpio_dir_out,
275 	.irq_set_type = mpc512x_irq_set_type,
276 };
277 
278 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
279 	.gpio_dir_out = mpc5125_gpio_dir_out,
280 	.irq_set_type = mpc512x_irq_set_type,
281 };
282 
283 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
284 	.gpio_get = mpc8572_gpio_get,
285 };
286 
287 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
288 	.irq_set_type = mpc8xxx_irq_set_type,
289 };
290 
291 static const struct of_device_id mpc8xxx_gpio_ids[] = {
292 	{ .compatible = "fsl,mpc8349-gpio", },
293 	{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
294 	{ .compatible = "fsl,mpc8610-gpio", },
295 	{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
296 	{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
297 	{ .compatible = "fsl,pq3-gpio",     },
298 	{ .compatible = "fsl,ls1028a-gpio", },
299 	{ .compatible = "fsl,ls1088a-gpio", },
300 	{ .compatible = "fsl,qoriq-gpio",   },
301 	{}
302 };
303 
304 static int mpc8xxx_probe(struct platform_device *pdev)
305 {
306 	struct device_node *np = pdev->dev.of_node;
307 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
308 	struct gpio_chip	*gc;
309 	const struct mpc8xxx_gpio_devtype *devtype = NULL;
310 	struct fwnode_handle *fwnode;
311 	int ret;
312 
313 	mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
314 	if (!mpc8xxx_gc)
315 		return -ENOMEM;
316 
317 	platform_set_drvdata(pdev, mpc8xxx_gc);
318 
319 	raw_spin_lock_init(&mpc8xxx_gc->lock);
320 
321 	mpc8xxx_gc->regs = devm_platform_ioremap_resource(pdev, 0);
322 	if (IS_ERR(mpc8xxx_gc->regs))
323 		return PTR_ERR(mpc8xxx_gc->regs);
324 
325 	gc = &mpc8xxx_gc->gc;
326 	gc->parent = &pdev->dev;
327 
328 	if (device_property_read_bool(&pdev->dev, "little-endian")) {
329 		ret = bgpio_init(gc, &pdev->dev, 4,
330 				 mpc8xxx_gc->regs + GPIO_DAT,
331 				 NULL, NULL,
332 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
333 				 BGPIOF_BIG_ENDIAN);
334 		if (ret)
335 			return ret;
336 		dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
337 	} else {
338 		ret = bgpio_init(gc, &pdev->dev, 4,
339 				 mpc8xxx_gc->regs + GPIO_DAT,
340 				 NULL, NULL,
341 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
342 				 BGPIOF_BIG_ENDIAN
343 				 | BGPIOF_BIG_ENDIAN_BYTE_ORDER);
344 		if (ret)
345 			return ret;
346 		dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
347 	}
348 
349 	mpc8xxx_gc->direction_output = gc->direction_output;
350 
351 	devtype = device_get_match_data(&pdev->dev);
352 	if (!devtype)
353 		devtype = &mpc8xxx_gpio_devtype_default;
354 
355 	/*
356 	 * It's assumed that only a single type of gpio controller is available
357 	 * on the current machine, so overwriting global data is fine.
358 	 */
359 	if (devtype->irq_set_type)
360 		mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
361 
362 	if (devtype->gpio_dir_out)
363 		gc->direction_output = devtype->gpio_dir_out;
364 	if (devtype->gpio_get)
365 		gc->get = devtype->gpio_get;
366 
367 	gc->to_irq = mpc8xxx_gpio_to_irq;
368 
369 	/*
370 	 * The GPIO Input Buffer Enable register(GPIO_IBE) is used to control
371 	 * the input enable of each individual GPIO port.  When an individual
372 	 * GPIO port’s direction is set to input (GPIO_GPDIR[DRn=0]), the
373 	 * associated input enable must be set (GPIOxGPIE[IEn]=1) to propagate
374 	 * the port value to the GPIO Data Register.
375 	 */
376 	fwnode = dev_fwnode(&pdev->dev);
377 	if (of_device_is_compatible(np, "fsl,qoriq-gpio") ||
378 	    of_device_is_compatible(np, "fsl,ls1028a-gpio") ||
379 	    of_device_is_compatible(np, "fsl,ls1088a-gpio") ||
380 	    is_acpi_node(fwnode))
381 		gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
382 
383 	ret = devm_gpiochip_add_data(&pdev->dev, gc, mpc8xxx_gc);
384 	if (ret) {
385 		dev_err(&pdev->dev,
386 			"GPIO chip registration failed with status %d\n", ret);
387 		return ret;
388 	}
389 
390 	mpc8xxx_gc->irqn = platform_get_irq(pdev, 0);
391 	if (mpc8xxx_gc->irqn < 0)
392 		return mpc8xxx_gc->irqn;
393 
394 	mpc8xxx_gc->irq = irq_domain_create_linear(fwnode,
395 						   MPC8XXX_GPIO_PINS,
396 						   &mpc8xxx_gpio_irq_ops,
397 						   mpc8xxx_gc);
398 
399 	if (!mpc8xxx_gc->irq)
400 		return 0;
401 
402 	/* ack and mask all irqs */
403 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
404 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
405 
406 	ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn,
407 			       mpc8xxx_gpio_irq_cascade,
408 			       IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade",
409 			       mpc8xxx_gc);
410 	if (ret) {
411 		dev_err(&pdev->dev,
412 			"failed to devm_request_irq(%d), ret = %d\n",
413 			mpc8xxx_gc->irqn, ret);
414 		goto err;
415 	}
416 
417 	return 0;
418 err:
419 	irq_domain_remove(mpc8xxx_gc->irq);
420 	return ret;
421 }
422 
423 static int mpc8xxx_remove(struct platform_device *pdev)
424 {
425 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
426 
427 	if (mpc8xxx_gc->irq) {
428 		irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
429 		irq_domain_remove(mpc8xxx_gc->irq);
430 	}
431 
432 	return 0;
433 }
434 
435 #ifdef CONFIG_ACPI
436 static const struct acpi_device_id gpio_acpi_ids[] = {
437 	{"NXP0031",},
438 	{ }
439 };
440 MODULE_DEVICE_TABLE(acpi, gpio_acpi_ids);
441 #endif
442 
443 static struct platform_driver mpc8xxx_plat_driver = {
444 	.probe		= mpc8xxx_probe,
445 	.remove		= mpc8xxx_remove,
446 	.driver		= {
447 		.name = "gpio-mpc8xxx",
448 		.of_match_table	= mpc8xxx_gpio_ids,
449 		.acpi_match_table = ACPI_PTR(gpio_acpi_ids),
450 	},
451 };
452 
453 static int __init mpc8xxx_init(void)
454 {
455 	return platform_driver_register(&mpc8xxx_plat_driver);
456 }
457 
458 arch_initcall(mpc8xxx_init);
459