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v4.6
 
  1/*
  2 * GPIO interface for Intel Poulsbo SCH
  3 *
  4 *  Copyright (c) 2010 CompuLab Ltd
  5 *  Author: Denis Turischev <denis@compulab.co.il>
  6 *
  7 *  This program is free software; you can redistribute it and/or modify
  8 *  it under the terms of the GNU General Public License 2 as published
  9 *  by the Free Software Foundation.
 10 *
 11 *  This program is distributed in the hope that it will be useful,
 12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *  GNU General Public License for more details.
 15 *
 16 *  You should have received a copy of the GNU General Public License
 17 *  along with this program; see the file COPYING.  If not, write to
 18 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 19 */
 20
 21#include <linux/init.h>
 
 
 
 
 
 22#include <linux/kernel.h>
 23#include <linux/module.h>
 24#include <linux/io.h>
 25#include <linux/errno.h>
 26#include <linux/acpi.h>
 27#include <linux/platform_device.h>
 28#include <linux/pci_ids.h>
 29
 30#include <linux/gpio.h>
 31
 32#define GEN	0x00
 33#define GIO	0x04
 34#define GLV	0x08
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 35
 36struct sch_gpio {
 37	struct gpio_chip chip;
 
 38	spinlock_t lock;
 39	unsigned short iobase;
 40	unsigned short core_base;
 41	unsigned short resume_base;
 
 
 
 
 42};
 43
 44static unsigned sch_gpio_offset(struct sch_gpio *sch, unsigned gpio,
 45				unsigned reg)
 46{
 47	unsigned base = 0;
 48
 49	if (gpio >= sch->resume_base) {
 50		gpio -= sch->resume_base;
 51		base += 0x20;
 52	}
 53
 54	return base + reg + gpio / 8;
 55}
 56
 57static unsigned sch_gpio_bit(struct sch_gpio *sch, unsigned gpio)
 58{
 59	if (gpio >= sch->resume_base)
 60		gpio -= sch->resume_base;
 61	return gpio % 8;
 62}
 63
 64static int sch_gpio_reg_get(struct gpio_chip *gc, unsigned gpio, unsigned reg)
 65{
 66	struct sch_gpio *sch = gpiochip_get_data(gc);
 67	unsigned short offset, bit;
 68	u8 reg_val;
 69
 70	offset = sch_gpio_offset(sch, gpio, reg);
 71	bit = sch_gpio_bit(sch, gpio);
 72
 73	reg_val = !!(inb(sch->iobase + offset) & BIT(bit));
 74
 75	return reg_val;
 76}
 77
 78static void sch_gpio_reg_set(struct gpio_chip *gc, unsigned gpio, unsigned reg,
 79			     int val)
 80{
 81	struct sch_gpio *sch = gpiochip_get_data(gc);
 82	unsigned short offset, bit;
 83	u8 reg_val;
 84
 85	offset = sch_gpio_offset(sch, gpio, reg);
 86	bit = sch_gpio_bit(sch, gpio);
 87
 88	reg_val = inb(sch->iobase + offset);
 89
 90	if (val)
 91		outb(reg_val | BIT(bit), sch->iobase + offset);
 92	else
 93		outb((reg_val & ~BIT(bit)), sch->iobase + offset);
 94}
 95
 96static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num)
 97{
 98	struct sch_gpio *sch = gpiochip_get_data(gc);
 
 99
100	spin_lock(&sch->lock);
101	sch_gpio_reg_set(gc, gpio_num, GIO, 1);
102	spin_unlock(&sch->lock);
103	return 0;
104}
105
106static int sch_gpio_get(struct gpio_chip *gc, unsigned gpio_num)
107{
108	return sch_gpio_reg_get(gc, gpio_num, GLV);
 
 
109}
110
111static void sch_gpio_set(struct gpio_chip *gc, unsigned gpio_num, int val)
112{
113	struct sch_gpio *sch = gpiochip_get_data(gc);
 
114
115	spin_lock(&sch->lock);
116	sch_gpio_reg_set(gc, gpio_num, GLV, val);
117	spin_unlock(&sch->lock);
118}
119
120static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned gpio_num,
121				  int val)
122{
123	struct sch_gpio *sch = gpiochip_get_data(gc);
 
124
125	spin_lock(&sch->lock);
126	sch_gpio_reg_set(gc, gpio_num, GIO, 0);
127	spin_unlock(&sch->lock);
128
129	/*
130	 * according to the datasheet, writing to the level register has no
131	 * effect when GPIO is programmed as input.
132	 * Actually the the level register is read-only when configured as input.
133	 * Thus presetting the output level before switching to output is _NOT_ possible.
134	 * Hence we set the level after configuring the GPIO as output.
135	 * But we cannot prevent a short low pulse if direction is set to high
136	 * and an external pull-up is connected.
137	 */
138	sch_gpio_set(gc, gpio_num, val);
139	return 0;
140}
141
142static struct gpio_chip sch_gpio_chip = {
 
 
 
 
 
 
 
 
 
 
143	.label			= "sch_gpio",
144	.owner			= THIS_MODULE,
145	.direction_input	= sch_gpio_direction_in,
146	.get			= sch_gpio_get,
147	.direction_output	= sch_gpio_direction_out,
148	.set			= sch_gpio_set,
 
149};
150
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
151static int sch_gpio_probe(struct platform_device *pdev)
152{
 
153	struct sch_gpio *sch;
154	struct resource *res;
 
155
156	sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
157	if (!sch)
158		return -ENOMEM;
159
160	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
161	if (!res)
162		return -EBUSY;
163
164	if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
165				 pdev->name))
166		return -EBUSY;
167
168	spin_lock_init(&sch->lock);
169	sch->iobase = res->start;
170	sch->chip = sch_gpio_chip;
171	sch->chip.label = dev_name(&pdev->dev);
172	sch->chip.parent = &pdev->dev;
173
174	switch (pdev->id) {
175	case PCI_DEVICE_ID_INTEL_SCH_LPC:
176		sch->core_base = 0;
177		sch->resume_base = 10;
178		sch->chip.ngpio = 14;
179
180		/*
181		 * GPIO[6:0] enabled by default
182		 * GPIO7 is configured by the CMC as SLPIOVR
183		 * Enable GPIO[9:8] core powered gpios explicitly
184		 */
185		sch_gpio_reg_set(&sch->chip, 8, GEN, 1);
186		sch_gpio_reg_set(&sch->chip, 9, GEN, 1);
187		/*
188		 * SUS_GPIO[2:0] enabled by default
189		 * Enable SUS_GPIO3 resume powered gpio explicitly
190		 */
191		sch_gpio_reg_set(&sch->chip, 13, GEN, 1);
192		break;
193
194	case PCI_DEVICE_ID_INTEL_ITC_LPC:
195		sch->core_base = 0;
196		sch->resume_base = 5;
197		sch->chip.ngpio = 14;
198		break;
199
200	case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
201		sch->core_base = 0;
202		sch->resume_base = 21;
203		sch->chip.ngpio = 30;
204		break;
205
206	case PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB:
207		sch->core_base = 0;
208		sch->resume_base = 2;
209		sch->chip.ngpio = 8;
210		break;
211
212	default:
213		return -ENODEV;
214	}
215
216	platform_set_drvdata(pdev, sch);
217
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218	return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch);
219}
220
221static struct platform_driver sch_gpio_driver = {
222	.driver = {
223		.name = "sch_gpio",
224	},
225	.probe		= sch_gpio_probe,
226};
227
228module_platform_driver(sch_gpio_driver);
229
230MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
231MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
232MODULE_LICENSE("GPL");
233MODULE_ALIAS("platform:sch_gpio");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * GPIO interface for Intel Poulsbo SCH
  4 *
  5 *  Copyright (c) 2010 CompuLab Ltd
  6 *  Author: Denis Turischev <denis@compulab.co.il>
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 */
  8
  9#include <linux/acpi.h>
 10#include <linux/bitops.h>
 11#include <linux/errno.h>
 12#include <linux/gpio/driver.h>
 13#include <linux/io.h>
 14#include <linux/irq.h>
 15#include <linux/kernel.h>
 16#include <linux/module.h>
 
 
 
 
 17#include <linux/pci_ids.h>
 18#include <linux/platform_device.h>
 19#include <linux/types.h>
 20
 21#define GEN	0x00
 22#define GIO	0x04
 23#define GLV	0x08
 24#define GTPE	0x0c
 25#define GTNE	0x10
 26#define GGPE	0x14
 27#define GSMI	0x18
 28#define GTS	0x1c
 29
 30#define CORE_BANK_OFFSET	0x00
 31#define RESUME_BANK_OFFSET	0x20
 32
 33/*
 34 * iLB datasheet describes GPE0BLK registers, in particular GPE0E.GPIO bit.
 35 * Document Number: 328195-001
 36 */
 37#define GPE0E_GPIO	14
 38
 39struct sch_gpio {
 40	struct gpio_chip chip;
 41	struct irq_chip irqchip;
 42	spinlock_t lock;
 43	unsigned short iobase;
 
 44	unsigned short resume_base;
 45
 46	/* GPE handling */
 47	u32 gpe;
 48	acpi_gpe_handler gpe_handler;
 49};
 50
 51static unsigned int sch_gpio_offset(struct sch_gpio *sch, unsigned int gpio,
 52				unsigned int reg)
 53{
 54	unsigned int base = CORE_BANK_OFFSET;
 55
 56	if (gpio >= sch->resume_base) {
 57		gpio -= sch->resume_base;
 58		base = RESUME_BANK_OFFSET;
 59	}
 60
 61	return base + reg + gpio / 8;
 62}
 63
 64static unsigned int sch_gpio_bit(struct sch_gpio *sch, unsigned int gpio)
 65{
 66	if (gpio >= sch->resume_base)
 67		gpio -= sch->resume_base;
 68	return gpio % 8;
 69}
 70
 71static int sch_gpio_reg_get(struct sch_gpio *sch, unsigned int gpio, unsigned int reg)
 72{
 
 73	unsigned short offset, bit;
 74	u8 reg_val;
 75
 76	offset = sch_gpio_offset(sch, gpio, reg);
 77	bit = sch_gpio_bit(sch, gpio);
 78
 79	reg_val = !!(inb(sch->iobase + offset) & BIT(bit));
 80
 81	return reg_val;
 82}
 83
 84static void sch_gpio_reg_set(struct sch_gpio *sch, unsigned int gpio, unsigned int reg,
 85			     int val)
 86{
 
 87	unsigned short offset, bit;
 88	u8 reg_val;
 89
 90	offset = sch_gpio_offset(sch, gpio, reg);
 91	bit = sch_gpio_bit(sch, gpio);
 92
 93	reg_val = inb(sch->iobase + offset);
 94
 95	if (val)
 96		outb(reg_val | BIT(bit), sch->iobase + offset);
 97	else
 98		outb((reg_val & ~BIT(bit)), sch->iobase + offset);
 99}
100
101static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned int gpio_num)
102{
103	struct sch_gpio *sch = gpiochip_get_data(gc);
104	unsigned long flags;
105
106	spin_lock_irqsave(&sch->lock, flags);
107	sch_gpio_reg_set(sch, gpio_num, GIO, 1);
108	spin_unlock_irqrestore(&sch->lock, flags);
109	return 0;
110}
111
112static int sch_gpio_get(struct gpio_chip *gc, unsigned int gpio_num)
113{
114	struct sch_gpio *sch = gpiochip_get_data(gc);
115
116	return sch_gpio_reg_get(sch, gpio_num, GLV);
117}
118
119static void sch_gpio_set(struct gpio_chip *gc, unsigned int gpio_num, int val)
120{
121	struct sch_gpio *sch = gpiochip_get_data(gc);
122	unsigned long flags;
123
124	spin_lock_irqsave(&sch->lock, flags);
125	sch_gpio_reg_set(sch, gpio_num, GLV, val);
126	spin_unlock_irqrestore(&sch->lock, flags);
127}
128
129static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned int gpio_num,
130				  int val)
131{
132	struct sch_gpio *sch = gpiochip_get_data(gc);
133	unsigned long flags;
134
135	spin_lock_irqsave(&sch->lock, flags);
136	sch_gpio_reg_set(sch, gpio_num, GIO, 0);
137	spin_unlock_irqrestore(&sch->lock, flags);
138
139	/*
140	 * according to the datasheet, writing to the level register has no
141	 * effect when GPIO is programmed as input.
142	 * Actually the the level register is read-only when configured as input.
143	 * Thus presetting the output level before switching to output is _NOT_ possible.
144	 * Hence we set the level after configuring the GPIO as output.
145	 * But we cannot prevent a short low pulse if direction is set to high
146	 * and an external pull-up is connected.
147	 */
148	sch_gpio_set(gc, gpio_num, val);
149	return 0;
150}
151
152static int sch_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio_num)
153{
154	struct sch_gpio *sch = gpiochip_get_data(gc);
155
156	if (sch_gpio_reg_get(sch, gpio_num, GIO))
157		return GPIO_LINE_DIRECTION_IN;
158
159	return GPIO_LINE_DIRECTION_OUT;
160}
161
162static const struct gpio_chip sch_gpio_chip = {
163	.label			= "sch_gpio",
164	.owner			= THIS_MODULE,
165	.direction_input	= sch_gpio_direction_in,
166	.get			= sch_gpio_get,
167	.direction_output	= sch_gpio_direction_out,
168	.set			= sch_gpio_set,
169	.get_direction		= sch_gpio_get_direction,
170};
171
172static int sch_irq_type(struct irq_data *d, unsigned int type)
173{
174	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
175	struct sch_gpio *sch = gpiochip_get_data(gc);
176	irq_hw_number_t gpio_num = irqd_to_hwirq(d);
177	unsigned long flags;
178	int rising, falling;
179
180	switch (type & IRQ_TYPE_SENSE_MASK) {
181	case IRQ_TYPE_EDGE_RISING:
182		rising = 1;
183		falling = 0;
184		break;
185	case IRQ_TYPE_EDGE_FALLING:
186		rising = 0;
187		falling = 1;
188		break;
189	case IRQ_TYPE_EDGE_BOTH:
190		rising = 1;
191		falling = 1;
192		break;
193	default:
194		return -EINVAL;
195	}
196
197	spin_lock_irqsave(&sch->lock, flags);
198
199	sch_gpio_reg_set(sch, gpio_num, GTPE, rising);
200	sch_gpio_reg_set(sch, gpio_num, GTNE, falling);
201
202	irq_set_handler_locked(d, handle_edge_irq);
203
204	spin_unlock_irqrestore(&sch->lock, flags);
205
206	return 0;
207}
208
209static void sch_irq_ack(struct irq_data *d)
210{
211	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
212	struct sch_gpio *sch = gpiochip_get_data(gc);
213	irq_hw_number_t gpio_num = irqd_to_hwirq(d);
214	unsigned long flags;
215
216	spin_lock_irqsave(&sch->lock, flags);
217	sch_gpio_reg_set(sch, gpio_num, GTS, 1);
218	spin_unlock_irqrestore(&sch->lock, flags);
219}
220
221static void sch_irq_mask_unmask(struct irq_data *d, int val)
222{
223	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
224	struct sch_gpio *sch = gpiochip_get_data(gc);
225	irq_hw_number_t gpio_num = irqd_to_hwirq(d);
226	unsigned long flags;
227
228	spin_lock_irqsave(&sch->lock, flags);
229	sch_gpio_reg_set(sch, gpio_num, GGPE, val);
230	spin_unlock_irqrestore(&sch->lock, flags);
231}
232
233static void sch_irq_mask(struct irq_data *d)
234{
235	sch_irq_mask_unmask(d, 0);
236}
237
238static void sch_irq_unmask(struct irq_data *d)
239{
240	sch_irq_mask_unmask(d, 1);
241}
242
243static u32 sch_gpio_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context)
244{
245	struct sch_gpio *sch = context;
246	struct gpio_chip *gc = &sch->chip;
247	unsigned long core_status, resume_status;
248	unsigned long pending;
249	unsigned long flags;
250	int offset;
251	u32 ret;
252
253	spin_lock_irqsave(&sch->lock, flags);
254
255	core_status = inl(sch->iobase + CORE_BANK_OFFSET + GTS);
256	resume_status = inl(sch->iobase + RESUME_BANK_OFFSET + GTS);
257
258	spin_unlock_irqrestore(&sch->lock, flags);
259
260	pending = (resume_status << sch->resume_base) | core_status;
261	for_each_set_bit(offset, &pending, sch->chip.ngpio)
262		generic_handle_irq(irq_find_mapping(gc->irq.domain, offset));
263
264	/* Set returning value depending on whether we handled an interrupt */
265	ret = pending ? ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
266
267	/* Acknowledge GPE to ACPICA */
268	ret |= ACPI_REENABLE_GPE;
269
270	return ret;
271}
272
273static void sch_gpio_remove_gpe_handler(void *data)
274{
275	struct sch_gpio *sch = data;
276
277	acpi_disable_gpe(NULL, sch->gpe);
278	acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler);
279}
280
281static int sch_gpio_install_gpe_handler(struct sch_gpio *sch)
282{
283	struct device *dev = sch->chip.parent;
284	acpi_status status;
285
286	status = acpi_install_gpe_handler(NULL, sch->gpe, ACPI_GPE_LEVEL_TRIGGERED,
287					  sch->gpe_handler, sch);
288	if (ACPI_FAILURE(status)) {
289		dev_err(dev, "Failed to install GPE handler for %u: %s\n",
290			sch->gpe, acpi_format_exception(status));
291		return -ENODEV;
292	}
293
294	status = acpi_enable_gpe(NULL, sch->gpe);
295	if (ACPI_FAILURE(status)) {
296		dev_err(dev, "Failed to enable GPE handler for %u: %s\n",
297			sch->gpe, acpi_format_exception(status));
298		acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler);
299		return -ENODEV;
300	}
301
302	return devm_add_action_or_reset(dev, sch_gpio_remove_gpe_handler, sch);
303}
304
305static int sch_gpio_probe(struct platform_device *pdev)
306{
307	struct gpio_irq_chip *girq;
308	struct sch_gpio *sch;
309	struct resource *res;
310	int ret;
311
312	sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
313	if (!sch)
314		return -ENOMEM;
315
316	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
317	if (!res)
318		return -EBUSY;
319
320	if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
321				 pdev->name))
322		return -EBUSY;
323
324	spin_lock_init(&sch->lock);
325	sch->iobase = res->start;
326	sch->chip = sch_gpio_chip;
327	sch->chip.label = dev_name(&pdev->dev);
328	sch->chip.parent = &pdev->dev;
329
330	switch (pdev->id) {
331	case PCI_DEVICE_ID_INTEL_SCH_LPC:
 
332		sch->resume_base = 10;
333		sch->chip.ngpio = 14;
334
335		/*
336		 * GPIO[6:0] enabled by default
337		 * GPIO7 is configured by the CMC as SLPIOVR
338		 * Enable GPIO[9:8] core powered gpios explicitly
339		 */
340		sch_gpio_reg_set(sch, 8, GEN, 1);
341		sch_gpio_reg_set(sch, 9, GEN, 1);
342		/*
343		 * SUS_GPIO[2:0] enabled by default
344		 * Enable SUS_GPIO3 resume powered gpio explicitly
345		 */
346		sch_gpio_reg_set(sch, 13, GEN, 1);
347		break;
348
349	case PCI_DEVICE_ID_INTEL_ITC_LPC:
 
350		sch->resume_base = 5;
351		sch->chip.ngpio = 14;
352		break;
353
354	case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
 
355		sch->resume_base = 21;
356		sch->chip.ngpio = 30;
357		break;
358
359	case PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB:
 
360		sch->resume_base = 2;
361		sch->chip.ngpio = 8;
362		break;
363
364	default:
365		return -ENODEV;
366	}
367
368	platform_set_drvdata(pdev, sch);
369
370	sch->irqchip.name = "sch_gpio";
371	sch->irqchip.irq_ack = sch_irq_ack;
372	sch->irqchip.irq_mask = sch_irq_mask;
373	sch->irqchip.irq_unmask = sch_irq_unmask;
374	sch->irqchip.irq_set_type = sch_irq_type;
375
376	girq = &sch->chip.irq;
377	girq->chip = &sch->irqchip;
378	girq->num_parents = 0;
379	girq->parents = NULL;
380	girq->parent_handler = NULL;
381	girq->default_type = IRQ_TYPE_NONE;
382	girq->handler = handle_bad_irq;
383
384	/* GPE setup is optional */
385	sch->gpe = GPE0E_GPIO;
386	sch->gpe_handler = sch_gpio_gpe_handler;
387
388	ret = sch_gpio_install_gpe_handler(sch);
389	if (ret)
390		dev_warn(&pdev->dev, "Can't setup GPE, no IRQ support\n");
391
392	return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch);
393}
394
395static struct platform_driver sch_gpio_driver = {
396	.driver = {
397		.name = "sch_gpio",
398	},
399	.probe		= sch_gpio_probe,
400};
401
402module_platform_driver(sch_gpio_driver);
403
404MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
405MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
406MODULE_LICENSE("GPL v2");
407MODULE_ALIAS("platform:sch_gpio");