xref: /openbmc/linux/drivers/gpio/gpio-timberdale.c (revision 9f5132ae82fdbb047cc187bf689a81c8cc0de7fa)
1c103de24SGrant Likely /*
2c103de24SGrant Likely  * Timberdale FPGA GPIO driver
3c103de24SGrant Likely  * Copyright (c) 2009 Intel Corporation
4c103de24SGrant Likely  *
5c103de24SGrant Likely  * This program is free software; you can redistribute it and/or modify
6c103de24SGrant Likely  * it under the terms of the GNU General Public License version 2 as
7c103de24SGrant Likely  * published by the Free Software Foundation.
8c103de24SGrant Likely  *
9c103de24SGrant Likely  * This program is distributed in the hope that it will be useful,
10c103de24SGrant Likely  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11c103de24SGrant Likely  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12c103de24SGrant Likely  * GNU General Public License for more details.
13c103de24SGrant Likely  *
14c103de24SGrant Likely  * You should have received a copy of the GNU General Public License
15c103de24SGrant Likely  * along with this program; if not, write to the Free Software
16c103de24SGrant Likely  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17c103de24SGrant Likely  */
18c103de24SGrant Likely 
19c103de24SGrant Likely /* Supports:
20c103de24SGrant Likely  * Timberdale FPGA GPIO
21c103de24SGrant Likely  */
22c103de24SGrant Likely 
23c103de24SGrant Likely #include <linux/module.h>
24c103de24SGrant Likely #include <linux/gpio.h>
25c103de24SGrant Likely #include <linux/platform_device.h>
26c103de24SGrant Likely #include <linux/irq.h>
27c103de24SGrant Likely #include <linux/io.h>
28c103de24SGrant Likely #include <linux/timb_gpio.h>
29c103de24SGrant Likely #include <linux/interrupt.h>
30c103de24SGrant Likely #include <linux/slab.h>
31c103de24SGrant Likely 
32c103de24SGrant Likely #define DRIVER_NAME "timb-gpio"
33c103de24SGrant Likely 
34c103de24SGrant Likely #define TGPIOVAL	0x00
35c103de24SGrant Likely #define TGPIODIR	0x04
36c103de24SGrant Likely #define TGPIO_IER	0x08
37c103de24SGrant Likely #define TGPIO_ISR	0x0c
38c103de24SGrant Likely #define TGPIO_IPR	0x10
39c103de24SGrant Likely #define TGPIO_ICR	0x14
40c103de24SGrant Likely #define TGPIO_FLR	0x18
41c103de24SGrant Likely #define TGPIO_LVR	0x1c
42c103de24SGrant Likely #define TGPIO_VER	0x20
43c103de24SGrant Likely #define TGPIO_BFLR	0x24
44c103de24SGrant Likely 
45c103de24SGrant Likely struct timbgpio {
46c103de24SGrant Likely 	void __iomem		*membase;
47c103de24SGrant Likely 	spinlock_t		lock; /* mutual exclusion */
48c103de24SGrant Likely 	struct gpio_chip	gpio;
49c103de24SGrant Likely 	int			irq_base;
50c103de24SGrant Likely 	unsigned long		last_ier;
51c103de24SGrant Likely };
52c103de24SGrant Likely 
53c103de24SGrant Likely static int timbgpio_update_bit(struct gpio_chip *gpio, unsigned index,
54c103de24SGrant Likely 	unsigned offset, bool enabled)
55c103de24SGrant Likely {
56c103de24SGrant Likely 	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
57c103de24SGrant Likely 	u32 reg;
58c103de24SGrant Likely 
59c103de24SGrant Likely 	spin_lock(&tgpio->lock);
60c103de24SGrant Likely 	reg = ioread32(tgpio->membase + offset);
61c103de24SGrant Likely 
62c103de24SGrant Likely 	if (enabled)
63c103de24SGrant Likely 		reg |= (1 << index);
64c103de24SGrant Likely 	else
65c103de24SGrant Likely 		reg &= ~(1 << index);
66c103de24SGrant Likely 
67c103de24SGrant Likely 	iowrite32(reg, tgpio->membase + offset);
68c103de24SGrant Likely 	spin_unlock(&tgpio->lock);
69c103de24SGrant Likely 
70c103de24SGrant Likely 	return 0;
71c103de24SGrant Likely }
72c103de24SGrant Likely 
73c103de24SGrant Likely static int timbgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
74c103de24SGrant Likely {
75c103de24SGrant Likely 	return timbgpio_update_bit(gpio, nr, TGPIODIR, true);
76c103de24SGrant Likely }
77c103de24SGrant Likely 
78c103de24SGrant Likely static int timbgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
79c103de24SGrant Likely {
80c103de24SGrant Likely 	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
81c103de24SGrant Likely 	u32 value;
82c103de24SGrant Likely 
83c103de24SGrant Likely 	value = ioread32(tgpio->membase + TGPIOVAL);
84c103de24SGrant Likely 	return (value & (1 << nr)) ? 1 : 0;
85c103de24SGrant Likely }
86c103de24SGrant Likely 
87c103de24SGrant Likely static int timbgpio_gpio_direction_output(struct gpio_chip *gpio,
88c103de24SGrant Likely 						unsigned nr, int val)
89c103de24SGrant Likely {
90c103de24SGrant Likely 	return timbgpio_update_bit(gpio, nr, TGPIODIR, false);
91c103de24SGrant Likely }
92c103de24SGrant Likely 
93c103de24SGrant Likely static void timbgpio_gpio_set(struct gpio_chip *gpio,
94c103de24SGrant Likely 				unsigned nr, int val)
95c103de24SGrant Likely {
96c103de24SGrant Likely 	timbgpio_update_bit(gpio, nr, TGPIOVAL, val != 0);
97c103de24SGrant Likely }
98c103de24SGrant Likely 
99c103de24SGrant Likely static int timbgpio_to_irq(struct gpio_chip *gpio, unsigned offset)
100c103de24SGrant Likely {
101c103de24SGrant Likely 	struct timbgpio *tgpio = container_of(gpio, struct timbgpio, gpio);
102c103de24SGrant Likely 
103c103de24SGrant Likely 	if (tgpio->irq_base <= 0)
104c103de24SGrant Likely 		return -EINVAL;
105c103de24SGrant Likely 
106c103de24SGrant Likely 	return tgpio->irq_base + offset;
107c103de24SGrant Likely }
108c103de24SGrant Likely 
109c103de24SGrant Likely /*
110c103de24SGrant Likely  * GPIO IRQ
111c103de24SGrant Likely  */
112c103de24SGrant Likely static void timbgpio_irq_disable(struct irq_data *d)
113c103de24SGrant Likely {
114c103de24SGrant Likely 	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
115c103de24SGrant Likely 	int offset = d->irq - tgpio->irq_base;
116c103de24SGrant Likely 	unsigned long flags;
117c103de24SGrant Likely 
118c103de24SGrant Likely 	spin_lock_irqsave(&tgpio->lock, flags);
119d79550a7SDan Carpenter 	tgpio->last_ier &= ~(1UL << offset);
120c103de24SGrant Likely 	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
121c103de24SGrant Likely 	spin_unlock_irqrestore(&tgpio->lock, flags);
122c103de24SGrant Likely }
123c103de24SGrant Likely 
124c103de24SGrant Likely static void timbgpio_irq_enable(struct irq_data *d)
125c103de24SGrant Likely {
126c103de24SGrant Likely 	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
127c103de24SGrant Likely 	int offset = d->irq - tgpio->irq_base;
128c103de24SGrant Likely 	unsigned long flags;
129c103de24SGrant Likely 
130c103de24SGrant Likely 	spin_lock_irqsave(&tgpio->lock, flags);
131d79550a7SDan Carpenter 	tgpio->last_ier |= 1UL << offset;
132c103de24SGrant Likely 	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
133c103de24SGrant Likely 	spin_unlock_irqrestore(&tgpio->lock, flags);
134c103de24SGrant Likely }
135c103de24SGrant Likely 
136c103de24SGrant Likely static int timbgpio_irq_type(struct irq_data *d, unsigned trigger)
137c103de24SGrant Likely {
138c103de24SGrant Likely 	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
139c103de24SGrant Likely 	int offset = d->irq - tgpio->irq_base;
140c103de24SGrant Likely 	unsigned long flags;
141c103de24SGrant Likely 	u32 lvr, flr, bflr = 0;
142c103de24SGrant Likely 	u32 ver;
143c103de24SGrant Likely 	int ret = 0;
144c103de24SGrant Likely 
145c103de24SGrant Likely 	if (offset < 0 || offset > tgpio->gpio.ngpio)
146c103de24SGrant Likely 		return -EINVAL;
147c103de24SGrant Likely 
148c103de24SGrant Likely 	ver = ioread32(tgpio->membase + TGPIO_VER);
149c103de24SGrant Likely 
150c103de24SGrant Likely 	spin_lock_irqsave(&tgpio->lock, flags);
151c103de24SGrant Likely 
152c103de24SGrant Likely 	lvr = ioread32(tgpio->membase + TGPIO_LVR);
153c103de24SGrant Likely 	flr = ioread32(tgpio->membase + TGPIO_FLR);
154c103de24SGrant Likely 	if (ver > 2)
155c103de24SGrant Likely 		bflr = ioread32(tgpio->membase + TGPIO_BFLR);
156c103de24SGrant Likely 
157c103de24SGrant Likely 	if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
158c103de24SGrant Likely 		bflr &= ~(1 << offset);
159c103de24SGrant Likely 		flr &= ~(1 << offset);
160c103de24SGrant Likely 		if (trigger & IRQ_TYPE_LEVEL_HIGH)
161c103de24SGrant Likely 			lvr |= 1 << offset;
162c103de24SGrant Likely 		else
163c103de24SGrant Likely 			lvr &= ~(1 << offset);
164c103de24SGrant Likely 	}
165c103de24SGrant Likely 
166c103de24SGrant Likely 	if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
167c103de24SGrant Likely 		if (ver < 3) {
168c103de24SGrant Likely 			ret = -EINVAL;
169c103de24SGrant Likely 			goto out;
1708a29a409SLaurent Navet 		} else {
171c103de24SGrant Likely 			flr |= 1 << offset;
172c103de24SGrant Likely 			bflr |= 1 << offset;
173c103de24SGrant Likely 		}
174c103de24SGrant Likely 	} else {
175c103de24SGrant Likely 		bflr &= ~(1 << offset);
176c103de24SGrant Likely 		flr |= 1 << offset;
177c103de24SGrant Likely 		if (trigger & IRQ_TYPE_EDGE_FALLING)
178c103de24SGrant Likely 			lvr &= ~(1 << offset);
179c103de24SGrant Likely 		else
180c103de24SGrant Likely 			lvr |= 1 << offset;
181c103de24SGrant Likely 	}
182c103de24SGrant Likely 
183c103de24SGrant Likely 	iowrite32(lvr, tgpio->membase + TGPIO_LVR);
184c103de24SGrant Likely 	iowrite32(flr, tgpio->membase + TGPIO_FLR);
185c103de24SGrant Likely 	if (ver > 2)
186c103de24SGrant Likely 		iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
187c103de24SGrant Likely 
188c103de24SGrant Likely 	iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
189c103de24SGrant Likely 
190c103de24SGrant Likely out:
191c103de24SGrant Likely 	spin_unlock_irqrestore(&tgpio->lock, flags);
192c103de24SGrant Likely 	return ret;
193c103de24SGrant Likely }
194c103de24SGrant Likely 
195c103de24SGrant Likely static void timbgpio_irq(unsigned int irq, struct irq_desc *desc)
196c103de24SGrant Likely {
197c103de24SGrant Likely 	struct timbgpio *tgpio = irq_get_handler_data(irq);
198c103de24SGrant Likely 	unsigned long ipr;
199c103de24SGrant Likely 	int offset;
200c103de24SGrant Likely 
201c103de24SGrant Likely 	desc->irq_data.chip->irq_ack(irq_get_irq_data(irq));
202c103de24SGrant Likely 	ipr = ioread32(tgpio->membase + TGPIO_IPR);
203c103de24SGrant Likely 	iowrite32(ipr, tgpio->membase + TGPIO_ICR);
204c103de24SGrant Likely 
205c103de24SGrant Likely 	/*
206c103de24SGrant Likely 	 * Some versions of the hardware trash the IER register if more than
207c103de24SGrant Likely 	 * one interrupt is received simultaneously.
208c103de24SGrant Likely 	 */
209c103de24SGrant Likely 	iowrite32(0, tgpio->membase + TGPIO_IER);
210c103de24SGrant Likely 
211c103de24SGrant Likely 	for_each_set_bit(offset, &ipr, tgpio->gpio.ngpio)
212c103de24SGrant Likely 		generic_handle_irq(timbgpio_to_irq(&tgpio->gpio, offset));
213c103de24SGrant Likely 
214c103de24SGrant Likely 	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
215c103de24SGrant Likely }
216c103de24SGrant Likely 
217c103de24SGrant Likely static struct irq_chip timbgpio_irqchip = {
218c103de24SGrant Likely 	.name		= "GPIO",
219c103de24SGrant Likely 	.irq_enable	= timbgpio_irq_enable,
220c103de24SGrant Likely 	.irq_disable	= timbgpio_irq_disable,
221c103de24SGrant Likely 	.irq_set_type	= timbgpio_irq_type,
222c103de24SGrant Likely };
223c103de24SGrant Likely 
2243836309dSBill Pemberton static int timbgpio_probe(struct platform_device *pdev)
225c103de24SGrant Likely {
226c103de24SGrant Likely 	int err, i;
2270ed3398eSabdoulaye berthe 	struct device *dev = &pdev->dev;
228c103de24SGrant Likely 	struct gpio_chip *gc;
229c103de24SGrant Likely 	struct timbgpio *tgpio;
230c103de24SGrant Likely 	struct resource *iomem;
231e56aee18SJingoo Han 	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
232c103de24SGrant Likely 	int irq = platform_get_irq(pdev, 0);
233c103de24SGrant Likely 
234c103de24SGrant Likely 	if (!pdata || pdata->nr_pins > 32) {
2350ed3398eSabdoulaye berthe 		dev_err(dev, "Invalid platform data\n");
2360ed3398eSabdoulaye berthe 		return -EINVAL;
237c103de24SGrant Likely 	}
238c103de24SGrant Likely 
239c103de24SGrant Likely 	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
240c103de24SGrant Likely 	if (!iomem) {
2410ed3398eSabdoulaye berthe 		dev_err(dev, "Unable to get resource\n");
2420ed3398eSabdoulaye berthe 		return -EINVAL;
243c103de24SGrant Likely 	}
244c103de24SGrant Likely 
2450ed3398eSabdoulaye berthe 	tgpio = devm_kzalloc(dev, sizeof(struct timbgpio), GFP_KERNEL);
246c103de24SGrant Likely 	if (!tgpio) {
2470ed3398eSabdoulaye berthe 		dev_err(dev, "Memory alloc failed\n");
2480ed3398eSabdoulaye berthe 		return -EINVAL;
249c103de24SGrant Likely 	}
250c103de24SGrant Likely 	tgpio->irq_base = pdata->irq_base;
251c103de24SGrant Likely 
252c103de24SGrant Likely 	spin_lock_init(&tgpio->lock);
253c103de24SGrant Likely 
2540ed3398eSabdoulaye berthe 	if (!devm_request_mem_region(dev, iomem->start, resource_size(iomem),
255c103de24SGrant Likely 				     DRIVER_NAME)) {
2560ed3398eSabdoulaye berthe 		dev_err(dev, "Region already claimed\n");
2570ed3398eSabdoulaye berthe 		return -EBUSY;
258c103de24SGrant Likely 	}
259c103de24SGrant Likely 
2600ed3398eSabdoulaye berthe 	tgpio->membase = devm_ioremap(dev, iomem->start, resource_size(iomem));
261c103de24SGrant Likely 	if (!tgpio->membase) {
2620ed3398eSabdoulaye berthe 		dev_err(dev, "Cannot ioremap\n");
2630ed3398eSabdoulaye berthe 		return -ENOMEM;
264c103de24SGrant Likely 	}
265c103de24SGrant Likely 
266c103de24SGrant Likely 	gc = &tgpio->gpio;
267c103de24SGrant Likely 
268c103de24SGrant Likely 	gc->label = dev_name(&pdev->dev);
269c103de24SGrant Likely 	gc->owner = THIS_MODULE;
270c103de24SGrant Likely 	gc->dev = &pdev->dev;
271c103de24SGrant Likely 	gc->direction_input = timbgpio_gpio_direction_input;
272c103de24SGrant Likely 	gc->get = timbgpio_gpio_get;
273c103de24SGrant Likely 	gc->direction_output = timbgpio_gpio_direction_output;
274c103de24SGrant Likely 	gc->set = timbgpio_gpio_set;
275c103de24SGrant Likely 	gc->to_irq = (irq >= 0 && tgpio->irq_base > 0) ? timbgpio_to_irq : NULL;
276c103de24SGrant Likely 	gc->dbg_show = NULL;
277c103de24SGrant Likely 	gc->base = pdata->gpio_base;
278c103de24SGrant Likely 	gc->ngpio = pdata->nr_pins;
2799fb1f39eSLinus Walleij 	gc->can_sleep = false;
280c103de24SGrant Likely 
281c103de24SGrant Likely 	err = gpiochip_add(gc);
282c103de24SGrant Likely 	if (err)
2830ed3398eSabdoulaye berthe 		return err;
284c103de24SGrant Likely 
285c103de24SGrant Likely 	platform_set_drvdata(pdev, tgpio);
286c103de24SGrant Likely 
287c103de24SGrant Likely 	/* make sure to disable interrupts */
288c103de24SGrant Likely 	iowrite32(0x0, tgpio->membase + TGPIO_IER);
289c103de24SGrant Likely 
290c103de24SGrant Likely 	if (irq < 0 || tgpio->irq_base <= 0)
291c103de24SGrant Likely 		return 0;
292c103de24SGrant Likely 
293c103de24SGrant Likely 	for (i = 0; i < pdata->nr_pins; i++) {
294e5428a68SLinus Walleij 		irq_set_chip_and_handler(tgpio->irq_base + i,
295e5428a68SLinus Walleij 			&timbgpio_irqchip, handle_simple_irq);
296c103de24SGrant Likely 		irq_set_chip_data(tgpio->irq_base + i, tgpio);
297c103de24SGrant Likely #ifdef CONFIG_ARM
298c103de24SGrant Likely 		set_irq_flags(tgpio->irq_base + i, IRQF_VALID | IRQF_PROBE);
299c103de24SGrant Likely #endif
300c103de24SGrant Likely 	}
301c103de24SGrant Likely 
302c103de24SGrant Likely 	irq_set_handler_data(irq, tgpio);
303c103de24SGrant Likely 	irq_set_chained_handler(irq, timbgpio_irq);
304c103de24SGrant Likely 
305c103de24SGrant Likely 	return 0;
306c103de24SGrant Likely }
307c103de24SGrant Likely 
308206210ceSBill Pemberton static int timbgpio_remove(struct platform_device *pdev)
309c103de24SGrant Likely {
310e56aee18SJingoo Han 	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
311c103de24SGrant Likely 	struct timbgpio *tgpio = platform_get_drvdata(pdev);
312c103de24SGrant Likely 	int irq = platform_get_irq(pdev, 0);
313c103de24SGrant Likely 
314c103de24SGrant Likely 	if (irq >= 0 && tgpio->irq_base > 0) {
315c103de24SGrant Likely 		int i;
316c103de24SGrant Likely 		for (i = 0; i < pdata->nr_pins; i++) {
317c103de24SGrant Likely 			irq_set_chip(tgpio->irq_base + i, NULL);
318c103de24SGrant Likely 			irq_set_chip_data(tgpio->irq_base + i, NULL);
319c103de24SGrant Likely 		}
320c103de24SGrant Likely 
321c103de24SGrant Likely 		irq_set_handler(irq, NULL);
322c103de24SGrant Likely 		irq_set_handler_data(irq, NULL);
323c103de24SGrant Likely 	}
324c103de24SGrant Likely 
325*9f5132aeSabdoulaye berthe 	gpiochip_remove(&tgpio->gpio);
326c103de24SGrant Likely 
327c103de24SGrant Likely 	return 0;
328c103de24SGrant Likely }
329c103de24SGrant Likely 
330c103de24SGrant Likely static struct platform_driver timbgpio_platform_driver = {
331c103de24SGrant Likely 	.driver = {
332c103de24SGrant Likely 		.name	= DRIVER_NAME,
333c103de24SGrant Likely 		.owner	= THIS_MODULE,
334c103de24SGrant Likely 	},
335c103de24SGrant Likely 	.probe		= timbgpio_probe,
336c103de24SGrant Likely 	.remove		= timbgpio_remove,
337c103de24SGrant Likely };
338c103de24SGrant Likely 
339c103de24SGrant Likely /*--------------------------------------------------------------------------*/
340c103de24SGrant Likely 
3416f61415eSMark Brown module_platform_driver(timbgpio_platform_driver);
342c103de24SGrant Likely 
343c103de24SGrant Likely MODULE_DESCRIPTION("Timberdale GPIO driver");
344c103de24SGrant Likely MODULE_LICENSE("GPL v2");
345c103de24SGrant Likely MODULE_AUTHOR("Mocean Laboratories");
346c103de24SGrant Likely MODULE_ALIAS("platform:"DRIVER_NAME);
347c103de24SGrant Likely 
348