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v4.6
  1/*
  2 * Timberdale FPGA GPIO driver
 
  3 * Copyright (c) 2009 Intel Corporation
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 *
  9 * This program is distributed in the hope that it will be useful,
 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12 * GNU General Public License for more details.
 13 *
 14 * You should have received a copy of the GNU General Public License
 15 * along with this program; if not, write to the Free Software
 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 17 */
 18
 19/* Supports:
 20 * Timberdale FPGA GPIO
 21 */
 22
 23#include <linux/module.h>
 24#include <linux/gpio.h>
 25#include <linux/platform_device.h>
 26#include <linux/irq.h>
 27#include <linux/io.h>
 28#include <linux/timb_gpio.h>
 29#include <linux/interrupt.h>
 30#include <linux/slab.h>
 31
 32#define DRIVER_NAME "timb-gpio"
 33
 34#define TGPIOVAL	0x00
 35#define TGPIODIR	0x04
 36#define TGPIO_IER	0x08
 37#define TGPIO_ISR	0x0c
 38#define TGPIO_IPR	0x10
 39#define TGPIO_ICR	0x14
 40#define TGPIO_FLR	0x18
 41#define TGPIO_LVR	0x1c
 42#define TGPIO_VER	0x20
 43#define TGPIO_BFLR	0x24
 44
 45struct timbgpio {
 46	void __iomem		*membase;
 47	spinlock_t		lock; /* mutual exclusion */
 48	struct gpio_chip	gpio;
 49	int			irq_base;
 50	unsigned long		last_ier;
 51};
 52
 53static int timbgpio_update_bit(struct gpio_chip *gpio, unsigned index,
 54	unsigned offset, bool enabled)
 55{
 56	struct timbgpio *tgpio = gpiochip_get_data(gpio);
 57	u32 reg;
 58
 59	spin_lock(&tgpio->lock);
 60	reg = ioread32(tgpio->membase + offset);
 61
 62	if (enabled)
 63		reg |= (1 << index);
 64	else
 65		reg &= ~(1 << index);
 66
 67	iowrite32(reg, tgpio->membase + offset);
 68	spin_unlock(&tgpio->lock);
 69
 70	return 0;
 71}
 72
 73static int timbgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
 74{
 75	return timbgpio_update_bit(gpio, nr, TGPIODIR, true);
 76}
 77
 78static int timbgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
 79{
 80	struct timbgpio *tgpio = gpiochip_get_data(gpio);
 81	u32 value;
 82
 83	value = ioread32(tgpio->membase + TGPIOVAL);
 84	return (value & (1 << nr)) ? 1 : 0;
 85}
 86
 87static int timbgpio_gpio_direction_output(struct gpio_chip *gpio,
 88						unsigned nr, int val)
 89{
 90	return timbgpio_update_bit(gpio, nr, TGPIODIR, false);
 91}
 92
 93static void timbgpio_gpio_set(struct gpio_chip *gpio,
 94				unsigned nr, int val)
 95{
 96	timbgpio_update_bit(gpio, nr, TGPIOVAL, val != 0);
 97}
 98
 99static int timbgpio_to_irq(struct gpio_chip *gpio, unsigned offset)
100{
101	struct timbgpio *tgpio = gpiochip_get_data(gpio);
102
103	if (tgpio->irq_base <= 0)
104		return -EINVAL;
105
106	return tgpio->irq_base + offset;
107}
108
109/*
110 * GPIO IRQ
111 */
112static void timbgpio_irq_disable(struct irq_data *d)
113{
114	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
115	int offset = d->irq - tgpio->irq_base;
116	unsigned long flags;
117
118	spin_lock_irqsave(&tgpio->lock, flags);
119	tgpio->last_ier &= ~(1UL << offset);
120	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
121	spin_unlock_irqrestore(&tgpio->lock, flags);
122}
123
124static void timbgpio_irq_enable(struct irq_data *d)
125{
126	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
127	int offset = d->irq - tgpio->irq_base;
128	unsigned long flags;
129
130	spin_lock_irqsave(&tgpio->lock, flags);
131	tgpio->last_ier |= 1UL << offset;
132	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
133	spin_unlock_irqrestore(&tgpio->lock, flags);
134}
135
136static int timbgpio_irq_type(struct irq_data *d, unsigned trigger)
137{
138	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
139	int offset = d->irq - tgpio->irq_base;
140	unsigned long flags;
141	u32 lvr, flr, bflr = 0;
142	u32 ver;
143	int ret = 0;
144
145	if (offset < 0 || offset > tgpio->gpio.ngpio)
146		return -EINVAL;
147
148	ver = ioread32(tgpio->membase + TGPIO_VER);
149
150	spin_lock_irqsave(&tgpio->lock, flags);
151
152	lvr = ioread32(tgpio->membase + TGPIO_LVR);
153	flr = ioread32(tgpio->membase + TGPIO_FLR);
154	if (ver > 2)
155		bflr = ioread32(tgpio->membase + TGPIO_BFLR);
156
157	if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
158		bflr &= ~(1 << offset);
159		flr &= ~(1 << offset);
160		if (trigger & IRQ_TYPE_LEVEL_HIGH)
161			lvr |= 1 << offset;
162		else
163			lvr &= ~(1 << offset);
164	}
165
166	if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
167		if (ver < 3) {
168			ret = -EINVAL;
169			goto out;
170		} else {
171			flr |= 1 << offset;
172			bflr |= 1 << offset;
173		}
174	} else {
175		bflr &= ~(1 << offset);
176		flr |= 1 << offset;
177		if (trigger & IRQ_TYPE_EDGE_FALLING)
178			lvr &= ~(1 << offset);
179		else
180			lvr |= 1 << offset;
181	}
182
183	iowrite32(lvr, tgpio->membase + TGPIO_LVR);
184	iowrite32(flr, tgpio->membase + TGPIO_FLR);
185	if (ver > 2)
186		iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
187
188	iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
189
190out:
191	spin_unlock_irqrestore(&tgpio->lock, flags);
192	return ret;
193}
194
195static void timbgpio_irq(struct irq_desc *desc)
196{
197	struct timbgpio *tgpio = irq_desc_get_handler_data(desc);
198	struct irq_data *data = irq_desc_get_irq_data(desc);
199	unsigned long ipr;
200	int offset;
201
202	data->chip->irq_ack(data);
203	ipr = ioread32(tgpio->membase + TGPIO_IPR);
204	iowrite32(ipr, tgpio->membase + TGPIO_ICR);
205
206	/*
207	 * Some versions of the hardware trash the IER register if more than
208	 * one interrupt is received simultaneously.
209	 */
210	iowrite32(0, tgpio->membase + TGPIO_IER);
211
212	for_each_set_bit(offset, &ipr, tgpio->gpio.ngpio)
213		generic_handle_irq(timbgpio_to_irq(&tgpio->gpio, offset));
214
215	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
216}
217
218static struct irq_chip timbgpio_irqchip = {
219	.name		= "GPIO",
220	.irq_enable	= timbgpio_irq_enable,
221	.irq_disable	= timbgpio_irq_disable,
222	.irq_set_type	= timbgpio_irq_type,
223};
224
225static int timbgpio_probe(struct platform_device *pdev)
226{
227	int err, i;
228	struct device *dev = &pdev->dev;
229	struct gpio_chip *gc;
230	struct timbgpio *tgpio;
231	struct resource *iomem;
232	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
233	int irq = platform_get_irq(pdev, 0);
234
235	if (!pdata || pdata->nr_pins > 32) {
236		dev_err(dev, "Invalid platform data\n");
237		return -EINVAL;
238	}
239
240	tgpio = devm_kzalloc(dev, sizeof(struct timbgpio), GFP_KERNEL);
241	if (!tgpio) {
242		dev_err(dev, "Memory alloc failed\n");
243		return -EINVAL;
244	}
245	tgpio->irq_base = pdata->irq_base;
246
247	spin_lock_init(&tgpio->lock);
248
249	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250	tgpio->membase = devm_ioremap_resource(dev, iomem);
251	if (IS_ERR(tgpio->membase))
252		return PTR_ERR(tgpio->membase);
253
254	gc = &tgpio->gpio;
255
256	gc->label = dev_name(&pdev->dev);
257	gc->owner = THIS_MODULE;
258	gc->parent = &pdev->dev;
259	gc->direction_input = timbgpio_gpio_direction_input;
260	gc->get = timbgpio_gpio_get;
261	gc->direction_output = timbgpio_gpio_direction_output;
262	gc->set = timbgpio_gpio_set;
263	gc->to_irq = (irq >= 0 && tgpio->irq_base > 0) ? timbgpio_to_irq : NULL;
264	gc->dbg_show = NULL;
265	gc->base = pdata->gpio_base;
266	gc->ngpio = pdata->nr_pins;
267	gc->can_sleep = false;
268
269	err = devm_gpiochip_add_data(&pdev->dev, gc, tgpio);
270	if (err)
271		return err;
272
273	platform_set_drvdata(pdev, tgpio);
274
275	/* make sure to disable interrupts */
276	iowrite32(0x0, tgpio->membase + TGPIO_IER);
277
278	if (irq < 0 || tgpio->irq_base <= 0)
279		return 0;
280
281	for (i = 0; i < pdata->nr_pins; i++) {
282		irq_set_chip_and_handler(tgpio->irq_base + i,
283			&timbgpio_irqchip, handle_simple_irq);
284		irq_set_chip_data(tgpio->irq_base + i, tgpio);
285		irq_clear_status_flags(tgpio->irq_base + i, IRQ_NOREQUEST | IRQ_NOPROBE);
286	}
287
288	irq_set_chained_handler_and_data(irq, timbgpio_irq, tgpio);
289
290	return 0;
291}
292
293static int timbgpio_remove(struct platform_device *pdev)
294{
295	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
296	struct timbgpio *tgpio = platform_get_drvdata(pdev);
297	int irq = platform_get_irq(pdev, 0);
298
299	if (irq >= 0 && tgpio->irq_base > 0) {
300		int i;
301		for (i = 0; i < pdata->nr_pins; i++) {
302			irq_set_chip(tgpio->irq_base + i, NULL);
303			irq_set_chip_data(tgpio->irq_base + i, NULL);
304		}
305
306		irq_set_handler(irq, NULL);
307		irq_set_handler_data(irq, NULL);
308	}
309
310	return 0;
311}
312
313static struct platform_driver timbgpio_platform_driver = {
314	.driver = {
315		.name	= DRIVER_NAME,
 
316	},
317	.probe		= timbgpio_probe,
318	.remove		= timbgpio_remove,
319};
320
321/*--------------------------------------------------------------------------*/
322
323module_platform_driver(timbgpio_platform_driver);
324
325MODULE_DESCRIPTION("Timberdale GPIO driver");
326MODULE_LICENSE("GPL v2");
327MODULE_AUTHOR("Mocean Laboratories");
328MODULE_ALIAS("platform:"DRIVER_NAME);
329
v4.17
  1/*
  2 * Timberdale FPGA GPIO driver
  3 * Author: Mocean Laboratories
  4 * Copyright (c) 2009 Intel Corporation
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 *
 15 * You should have received a copy of the GNU General Public License
 16 * along with this program; if not, write to the Free Software
 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 18 */
 19
 20/* Supports:
 21 * Timberdale FPGA GPIO
 22 */
 23
 24#include <linux/init.h>
 25#include <linux/gpio.h>
 26#include <linux/platform_device.h>
 27#include <linux/irq.h>
 28#include <linux/io.h>
 29#include <linux/timb_gpio.h>
 30#include <linux/interrupt.h>
 31#include <linux/slab.h>
 32
 33#define DRIVER_NAME "timb-gpio"
 34
 35#define TGPIOVAL	0x00
 36#define TGPIODIR	0x04
 37#define TGPIO_IER	0x08
 38#define TGPIO_ISR	0x0c
 39#define TGPIO_IPR	0x10
 40#define TGPIO_ICR	0x14
 41#define TGPIO_FLR	0x18
 42#define TGPIO_LVR	0x1c
 43#define TGPIO_VER	0x20
 44#define TGPIO_BFLR	0x24
 45
 46struct timbgpio {
 47	void __iomem		*membase;
 48	spinlock_t		lock; /* mutual exclusion */
 49	struct gpio_chip	gpio;
 50	int			irq_base;
 51	unsigned long		last_ier;
 52};
 53
 54static int timbgpio_update_bit(struct gpio_chip *gpio, unsigned index,
 55	unsigned offset, bool enabled)
 56{
 57	struct timbgpio *tgpio = gpiochip_get_data(gpio);
 58	u32 reg;
 59
 60	spin_lock(&tgpio->lock);
 61	reg = ioread32(tgpio->membase + offset);
 62
 63	if (enabled)
 64		reg |= (1 << index);
 65	else
 66		reg &= ~(1 << index);
 67
 68	iowrite32(reg, tgpio->membase + offset);
 69	spin_unlock(&tgpio->lock);
 70
 71	return 0;
 72}
 73
 74static int timbgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
 75{
 76	return timbgpio_update_bit(gpio, nr, TGPIODIR, true);
 77}
 78
 79static int timbgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
 80{
 81	struct timbgpio *tgpio = gpiochip_get_data(gpio);
 82	u32 value;
 83
 84	value = ioread32(tgpio->membase + TGPIOVAL);
 85	return (value & (1 << nr)) ? 1 : 0;
 86}
 87
 88static int timbgpio_gpio_direction_output(struct gpio_chip *gpio,
 89						unsigned nr, int val)
 90{
 91	return timbgpio_update_bit(gpio, nr, TGPIODIR, false);
 92}
 93
 94static void timbgpio_gpio_set(struct gpio_chip *gpio,
 95				unsigned nr, int val)
 96{
 97	timbgpio_update_bit(gpio, nr, TGPIOVAL, val != 0);
 98}
 99
100static int timbgpio_to_irq(struct gpio_chip *gpio, unsigned offset)
101{
102	struct timbgpio *tgpio = gpiochip_get_data(gpio);
103
104	if (tgpio->irq_base <= 0)
105		return -EINVAL;
106
107	return tgpio->irq_base + offset;
108}
109
110/*
111 * GPIO IRQ
112 */
113static void timbgpio_irq_disable(struct irq_data *d)
114{
115	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
116	int offset = d->irq - tgpio->irq_base;
117	unsigned long flags;
118
119	spin_lock_irqsave(&tgpio->lock, flags);
120	tgpio->last_ier &= ~(1UL << offset);
121	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
122	spin_unlock_irqrestore(&tgpio->lock, flags);
123}
124
125static void timbgpio_irq_enable(struct irq_data *d)
126{
127	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
128	int offset = d->irq - tgpio->irq_base;
129	unsigned long flags;
130
131	spin_lock_irqsave(&tgpio->lock, flags);
132	tgpio->last_ier |= 1UL << offset;
133	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
134	spin_unlock_irqrestore(&tgpio->lock, flags);
135}
136
137static int timbgpio_irq_type(struct irq_data *d, unsigned trigger)
138{
139	struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
140	int offset = d->irq - tgpio->irq_base;
141	unsigned long flags;
142	u32 lvr, flr, bflr = 0;
143	u32 ver;
144	int ret = 0;
145
146	if (offset < 0 || offset > tgpio->gpio.ngpio)
147		return -EINVAL;
148
149	ver = ioread32(tgpio->membase + TGPIO_VER);
150
151	spin_lock_irqsave(&tgpio->lock, flags);
152
153	lvr = ioread32(tgpio->membase + TGPIO_LVR);
154	flr = ioread32(tgpio->membase + TGPIO_FLR);
155	if (ver > 2)
156		bflr = ioread32(tgpio->membase + TGPIO_BFLR);
157
158	if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
159		bflr &= ~(1 << offset);
160		flr &= ~(1 << offset);
161		if (trigger & IRQ_TYPE_LEVEL_HIGH)
162			lvr |= 1 << offset;
163		else
164			lvr &= ~(1 << offset);
165	}
166
167	if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
168		if (ver < 3) {
169			ret = -EINVAL;
170			goto out;
171		} else {
172			flr |= 1 << offset;
173			bflr |= 1 << offset;
174		}
175	} else {
176		bflr &= ~(1 << offset);
177		flr |= 1 << offset;
178		if (trigger & IRQ_TYPE_EDGE_FALLING)
179			lvr &= ~(1 << offset);
180		else
181			lvr |= 1 << offset;
182	}
183
184	iowrite32(lvr, tgpio->membase + TGPIO_LVR);
185	iowrite32(flr, tgpio->membase + TGPIO_FLR);
186	if (ver > 2)
187		iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
188
189	iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
190
191out:
192	spin_unlock_irqrestore(&tgpio->lock, flags);
193	return ret;
194}
195
196static void timbgpio_irq(struct irq_desc *desc)
197{
198	struct timbgpio *tgpio = irq_desc_get_handler_data(desc);
199	struct irq_data *data = irq_desc_get_irq_data(desc);
200	unsigned long ipr;
201	int offset;
202
203	data->chip->irq_ack(data);
204	ipr = ioread32(tgpio->membase + TGPIO_IPR);
205	iowrite32(ipr, tgpio->membase + TGPIO_ICR);
206
207	/*
208	 * Some versions of the hardware trash the IER register if more than
209	 * one interrupt is received simultaneously.
210	 */
211	iowrite32(0, tgpio->membase + TGPIO_IER);
212
213	for_each_set_bit(offset, &ipr, tgpio->gpio.ngpio)
214		generic_handle_irq(timbgpio_to_irq(&tgpio->gpio, offset));
215
216	iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
217}
218
219static struct irq_chip timbgpio_irqchip = {
220	.name		= "GPIO",
221	.irq_enable	= timbgpio_irq_enable,
222	.irq_disable	= timbgpio_irq_disable,
223	.irq_set_type	= timbgpio_irq_type,
224};
225
226static int timbgpio_probe(struct platform_device *pdev)
227{
228	int err, i;
229	struct device *dev = &pdev->dev;
230	struct gpio_chip *gc;
231	struct timbgpio *tgpio;
232	struct resource *iomem;
233	struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
234	int irq = platform_get_irq(pdev, 0);
235
236	if (!pdata || pdata->nr_pins > 32) {
237		dev_err(dev, "Invalid platform data\n");
238		return -EINVAL;
239	}
240
241	tgpio = devm_kzalloc(dev, sizeof(*tgpio), GFP_KERNEL);
242	if (!tgpio)
 
243		return -EINVAL;
244
245	tgpio->irq_base = pdata->irq_base;
246
247	spin_lock_init(&tgpio->lock);
248
249	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250	tgpio->membase = devm_ioremap_resource(dev, iomem);
251	if (IS_ERR(tgpio->membase))
252		return PTR_ERR(tgpio->membase);
253
254	gc = &tgpio->gpio;
255
256	gc->label = dev_name(&pdev->dev);
257	gc->owner = THIS_MODULE;
258	gc->parent = &pdev->dev;
259	gc->direction_input = timbgpio_gpio_direction_input;
260	gc->get = timbgpio_gpio_get;
261	gc->direction_output = timbgpio_gpio_direction_output;
262	gc->set = timbgpio_gpio_set;
263	gc->to_irq = (irq >= 0 && tgpio->irq_base > 0) ? timbgpio_to_irq : NULL;
264	gc->dbg_show = NULL;
265	gc->base = pdata->gpio_base;
266	gc->ngpio = pdata->nr_pins;
267	gc->can_sleep = false;
268
269	err = devm_gpiochip_add_data(&pdev->dev, gc, tgpio);
270	if (err)
271		return err;
272
273	platform_set_drvdata(pdev, tgpio);
274
275	/* make sure to disable interrupts */
276	iowrite32(0x0, tgpio->membase + TGPIO_IER);
277
278	if (irq < 0 || tgpio->irq_base <= 0)
279		return 0;
280
281	for (i = 0; i < pdata->nr_pins; i++) {
282		irq_set_chip_and_handler(tgpio->irq_base + i,
283			&timbgpio_irqchip, handle_simple_irq);
284		irq_set_chip_data(tgpio->irq_base + i, tgpio);
285		irq_clear_status_flags(tgpio->irq_base + i, IRQ_NOREQUEST | IRQ_NOPROBE);
286	}
287
288	irq_set_chained_handler_and_data(irq, timbgpio_irq, tgpio);
289
290	return 0;
291}
292
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
293static struct platform_driver timbgpio_platform_driver = {
294	.driver = {
295		.name			= DRIVER_NAME,
296		.suppress_bind_attrs	= true,
297	},
298	.probe		= timbgpio_probe,
 
299};
300
301/*--------------------------------------------------------------------------*/
302
303builtin_platform_driver(timbgpio_platform_driver);