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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * GPIO driver for the ACCES PCIe-IDIO-24 family
  4 * Copyright (C) 2018 William Breathitt Gray
  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, but
 11 * WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 13 * General Public License for more details.
 14 *
 15 * This driver supports the following ACCES devices: PCIe-IDIO-24,
 16 * PCIe-IDI-24, PCIe-IDO-24, and PCIe-IDIO-12.
 17 */
 18#include <linux/bitmap.h>
 19#include <linux/bitops.h>
 20#include <linux/device.h>
 21#include <linux/errno.h>
 22#include <linux/gpio/driver.h>
 23#include <linux/interrupt.h>
 24#include <linux/irqdesc.h>
 25#include <linux/kernel.h>
 26#include <linux/module.h>
 27#include <linux/pci.h>
 28#include <linux/spinlock.h>
 29#include <linux/types.h>
 30
 31/*
 32 * PLX PEX8311 PCI LCS_INTCSR Interrupt Control/Status
 33 *
 34 * Bit: Description
 35 *   0: Enable Interrupt Sources (Bit 0)
 36 *   1: Enable Interrupt Sources (Bit 1)
 37 *   2: Generate Internal PCI Bus Internal SERR# Interrupt
 38 *   3: Mailbox Interrupt Enable
 39 *   4: Power Management Interrupt Enable
 40 *   5: Power Management Interrupt
 41 *   6: Slave Read Local Data Parity Check Error Enable
 42 *   7: Slave Read Local Data Parity Check Error Status
 43 *   8: Internal PCI Wire Interrupt Enable
 44 *   9: PCI Express Doorbell Interrupt Enable
 45 *  10: PCI Abort Interrupt Enable
 46 *  11: Local Interrupt Input Enable
 47 *  12: Retry Abort Enable
 48 *  13: PCI Express Doorbell Interrupt Active
 49 *  14: PCI Abort Interrupt Active
 50 *  15: Local Interrupt Input Active
 51 *  16: Local Interrupt Output Enable
 52 *  17: Local Doorbell Interrupt Enable
 53 *  18: DMA Channel 0 Interrupt Enable
 54 *  19: DMA Channel 1 Interrupt Enable
 55 *  20: Local Doorbell Interrupt Active
 56 *  21: DMA Channel 0 Interrupt Active
 57 *  22: DMA Channel 1 Interrupt Active
 58 *  23: Built-In Self-Test (BIST) Interrupt Active
 59 *  24: Direct Master was the Bus Master during a Master or Target Abort
 60 *  25: DMA Channel 0 was the Bus Master during a Master or Target Abort
 61 *  26: DMA Channel 1 was the Bus Master during a Master or Target Abort
 62 *  27: Target Abort after internal 256 consecutive Master Retrys
 63 *  28: PCI Bus wrote data to LCS_MBOX0
 64 *  29: PCI Bus wrote data to LCS_MBOX1
 65 *  30: PCI Bus wrote data to LCS_MBOX2
 66 *  31: PCI Bus wrote data to LCS_MBOX3
 67 */
 68#define PLX_PEX8311_PCI_LCS_INTCSR  0x68
 69#define INTCSR_INTERNAL_PCI_WIRE    BIT(8)
 70#define INTCSR_LOCAL_INPUT          BIT(11)
 71
 72/**
 73 * struct idio_24_gpio_reg - GPIO device registers structure
 74 * @out0_7:	Read: FET Outputs 0-7
 75 *		Write: FET Outputs 0-7
 76 * @out8_15:	Read: FET Outputs 8-15
 77 *		Write: FET Outputs 8-15
 78 * @out16_23:	Read: FET Outputs 16-23
 79 *		Write: FET Outputs 16-23
 80 * @ttl_out0_7:	Read: TTL/CMOS Outputs 0-7
 81 *		Write: TTL/CMOS Outputs 0-7
 82 * @in0_7:	Read: Isolated Inputs 0-7
 83 *		Write: Reserved
 84 * @in8_15:	Read: Isolated Inputs 8-15
 85 *		Write: Reserved
 86 * @in16_23:	Read: Isolated Inputs 16-23
 87 *		Write: Reserved
 88 * @ttl_in0_7:	Read: TTL/CMOS Inputs 0-7
 89 *		Write: Reserved
 90 * @cos0_7:	Read: COS Status Inputs 0-7
 91 *		Write: COS Clear Inputs 0-7
 92 * @cos8_15:	Read: COS Status Inputs 8-15
 93 *		Write: COS Clear Inputs 8-15
 94 * @cos16_23:	Read: COS Status Inputs 16-23
 95 *		Write: COS Clear Inputs 16-23
 96 * @cos_ttl0_7:	Read: COS Status TTL/CMOS 0-7
 97 *		Write: COS Clear TTL/CMOS 0-7
 98 * @ctl:	Read: Control Register
 99 *		Write: Control Register
100 * @reserved:	Read: Reserved
101 *		Write: Reserved
102 * @cos_enable:	Read: COS Enable
103 *		Write: COS Enable
104 * @soft_reset:	Read: IRQ Output Pin Status
105 *		Write: Software Board Reset
106 */
107struct idio_24_gpio_reg {
108	u8 out0_7;
109	u8 out8_15;
110	u8 out16_23;
111	u8 ttl_out0_7;
112	u8 in0_7;
113	u8 in8_15;
114	u8 in16_23;
115	u8 ttl_in0_7;
116	u8 cos0_7;
117	u8 cos8_15;
118	u8 cos16_23;
119	u8 cos_ttl0_7;
120	u8 ctl;
121	u8 reserved;
122	u8 cos_enable;
123	u8 soft_reset;
124};
125
126/**
127 * struct idio_24_gpio - GPIO device private data structure
128 * @chip:	instance of the gpio_chip
129 * @lock:	synchronization lock to prevent I/O race conditions
130 * @reg:	I/O address offset for the GPIO device registers
131 * @irq_mask:	I/O bits affected by interrupts
132 */
133struct idio_24_gpio {
134	struct gpio_chip chip;
135	raw_spinlock_t lock;
136	__u8 __iomem *plx;
137	struct idio_24_gpio_reg __iomem *reg;
138	unsigned long irq_mask;
139};
140
141static int idio_24_gpio_get_direction(struct gpio_chip *chip,
142	unsigned int offset)
143{
144	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
145	const unsigned long out_mode_mask = BIT(1);
146
147	/* FET Outputs */
148	if (offset < 24)
149		return GPIO_LINE_DIRECTION_OUT;
150
151	/* Isolated Inputs */
152	if (offset < 48)
153		return GPIO_LINE_DIRECTION_IN;
154
155	/* TTL/CMOS I/O */
156	/* OUT MODE = 1 when TTL/CMOS Output Mode is set */
157	if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
158		return GPIO_LINE_DIRECTION_OUT;
159
160	return GPIO_LINE_DIRECTION_IN;
161}
162
163static int idio_24_gpio_direction_input(struct gpio_chip *chip,
164	unsigned int offset)
165{
166	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
167	unsigned long flags;
168	unsigned int ctl_state;
169	const unsigned long out_mode_mask = BIT(1);
170
171	/* TTL/CMOS I/O */
172	if (offset > 47) {
173		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
174
175		/* Clear TTL/CMOS Output Mode */
176		ctl_state = ioread8(&idio24gpio->reg->ctl) & ~out_mode_mask;
177		iowrite8(ctl_state, &idio24gpio->reg->ctl);
178
179		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
180	}
181
182	return 0;
183}
184
185static int idio_24_gpio_direction_output(struct gpio_chip *chip,
186	unsigned int offset, int value)
187{
188	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
189	unsigned long flags;
190	unsigned int ctl_state;
191	const unsigned long out_mode_mask = BIT(1);
192
193	/* TTL/CMOS I/O */
194	if (offset > 47) {
195		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
196
197		/* Set TTL/CMOS Output Mode */
198		ctl_state = ioread8(&idio24gpio->reg->ctl) | out_mode_mask;
199		iowrite8(ctl_state, &idio24gpio->reg->ctl);
200
201		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
202	}
203
204	chip->set(chip, offset, value);
205	return 0;
206}
207
208static int idio_24_gpio_get(struct gpio_chip *chip, unsigned int offset)
209{
210	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
211	const unsigned long offset_mask = BIT(offset % 8);
212	const unsigned long out_mode_mask = BIT(1);
213
214	/* FET Outputs */
215	if (offset < 8)
216		return !!(ioread8(&idio24gpio->reg->out0_7) & offset_mask);
217
218	if (offset < 16)
219		return !!(ioread8(&idio24gpio->reg->out8_15) & offset_mask);
220
221	if (offset < 24)
222		return !!(ioread8(&idio24gpio->reg->out16_23) & offset_mask);
223
224	/* Isolated Inputs */
225	if (offset < 32)
226		return !!(ioread8(&idio24gpio->reg->in0_7) & offset_mask);
227
228	if (offset < 40)
229		return !!(ioread8(&idio24gpio->reg->in8_15) & offset_mask);
230
231	if (offset < 48)
232		return !!(ioread8(&idio24gpio->reg->in16_23) & offset_mask);
233
234	/* TTL/CMOS Outputs */
235	if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
236		return !!(ioread8(&idio24gpio->reg->ttl_out0_7) & offset_mask);
237
238	/* TTL/CMOS Inputs */
239	return !!(ioread8(&idio24gpio->reg->ttl_in0_7) & offset_mask);
240}
241
242static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
243	unsigned long *mask, unsigned long *bits)
244{
245	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
246	unsigned long offset;
247	unsigned long gpio_mask;
248	void __iomem *ports[] = {
249		&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
250		&idio24gpio->reg->out16_23, &idio24gpio->reg->in0_7,
251		&idio24gpio->reg->in8_15, &idio24gpio->reg->in16_23,
252	};
253	size_t index;
254	unsigned long port_state;
255	const unsigned long out_mode_mask = BIT(1);
256
257	/* clear bits array to a clean slate */
258	bitmap_zero(bits, chip->ngpio);
259
260	for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
261		index = offset / 8;
262
263		/* read bits from current gpio port (port 6 is TTL GPIO) */
264		if (index < 6)
265			port_state = ioread8(ports[index]);
266		else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
267			port_state = ioread8(&idio24gpio->reg->ttl_out0_7);
268		else
269			port_state = ioread8(&idio24gpio->reg->ttl_in0_7);
270
271		port_state &= gpio_mask;
272
273		bitmap_set_value8(bits, port_state, offset);
274	}
275
276	return 0;
277}
278
279static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset,
280	int value)
281{
282	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
283	const unsigned long out_mode_mask = BIT(1);
284	void __iomem *base;
285	const unsigned int mask = BIT(offset % 8);
286	unsigned long flags;
287	unsigned int out_state;
288
289	/* Isolated Inputs */
290	if (offset > 23 && offset < 48)
291		return;
292
293	/* TTL/CMOS Inputs */
294	if (offset > 47 && !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask))
295		return;
296
297	/* TTL/CMOS Outputs */
298	if (offset > 47)
299		base = &idio24gpio->reg->ttl_out0_7;
300	/* FET Outputs */
301	else if (offset > 15)
302		base = &idio24gpio->reg->out16_23;
303	else if (offset > 7)
304		base = &idio24gpio->reg->out8_15;
305	else
306		base = &idio24gpio->reg->out0_7;
307
308	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
309
310	if (value)
311		out_state = ioread8(base) | mask;
312	else
313		out_state = ioread8(base) & ~mask;
314
315	iowrite8(out_state, base);
316
317	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
318}
319
320static void idio_24_gpio_set_multiple(struct gpio_chip *chip,
321	unsigned long *mask, unsigned long *bits)
322{
323	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
324	unsigned long offset;
325	unsigned long gpio_mask;
326	void __iomem *ports[] = {
327		&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
328		&idio24gpio->reg->out16_23
329	};
330	size_t index;
331	unsigned long bitmask;
332	unsigned long flags;
333	unsigned long out_state;
334	const unsigned long out_mode_mask = BIT(1);
335
336	for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
337		index = offset / 8;
338
339		bitmask = bitmap_get_value8(bits, offset) & gpio_mask;
340
341		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
342
343		/* read bits from current gpio port (port 6 is TTL GPIO) */
344		if (index < 6) {
345			out_state = ioread8(ports[index]);
346		} else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask) {
347			out_state = ioread8(&idio24gpio->reg->ttl_out0_7);
348		} else {
349			/* skip TTL GPIO if set for input */
350			raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
351			continue;
352		}
353
354		/* set requested bit states */
355		out_state &= ~gpio_mask;
356		out_state |= bitmask;
357
358		/* write bits for current gpio port (port 6 is TTL GPIO) */
359		if (index < 6)
360			iowrite8(out_state, ports[index]);
361		else
362			iowrite8(out_state, &idio24gpio->reg->ttl_out0_7);
363
364		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
365	}
366}
367
368static void idio_24_irq_ack(struct irq_data *data)
369{
370}
371
372static void idio_24_irq_mask(struct irq_data *data)
373{
374	struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
375	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
376	unsigned long flags;
377	const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
378	unsigned char new_irq_mask;
379	const unsigned long bank_offset = bit_offset / 8;
380	unsigned char cos_enable_state;
381
382	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
383
384	idio24gpio->irq_mask &= ~BIT(bit_offset);
385	new_irq_mask = idio24gpio->irq_mask >> bank_offset * 8;
386
387	if (!new_irq_mask) {
388		cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
389
390		/* Disable Rising Edge detection */
391		cos_enable_state &= ~BIT(bank_offset);
392		/* Disable Falling Edge detection */
393		cos_enable_state &= ~BIT(bank_offset + 4);
394
395		iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
396	}
397
398	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
399}
400
401static void idio_24_irq_unmask(struct irq_data *data)
402{
403	struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
404	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
405	unsigned long flags;
406	unsigned char prev_irq_mask;
407	const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
408	const unsigned long bank_offset = bit_offset / 8;
409	unsigned char cos_enable_state;
410
411	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
412
413	prev_irq_mask = idio24gpio->irq_mask >> bank_offset * 8;
414	idio24gpio->irq_mask |= BIT(bit_offset);
415
416	if (!prev_irq_mask) {
417		cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
418
419		/* Enable Rising Edge detection */
420		cos_enable_state |= BIT(bank_offset);
421		/* Enable Falling Edge detection */
422		cos_enable_state |= BIT(bank_offset + 4);
423
424		iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
425	}
426
427	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
428}
429
430static int idio_24_irq_set_type(struct irq_data *data, unsigned int flow_type)
431{
432	/* The only valid irq types are none and both-edges */
433	if (flow_type != IRQ_TYPE_NONE &&
434		(flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH)
435		return -EINVAL;
436
437	return 0;
438}
439
440static struct irq_chip idio_24_irqchip = {
441	.name = "pcie-idio-24",
442	.irq_ack = idio_24_irq_ack,
443	.irq_mask = idio_24_irq_mask,
444	.irq_unmask = idio_24_irq_unmask,
445	.irq_set_type = idio_24_irq_set_type
446};
447
448static irqreturn_t idio_24_irq_handler(int irq, void *dev_id)
449{
450	struct idio_24_gpio *const idio24gpio = dev_id;
451	unsigned long irq_status;
452	struct gpio_chip *const chip = &idio24gpio->chip;
453	unsigned long irq_mask;
454	int gpio;
455
456	raw_spin_lock(&idio24gpio->lock);
457
458	/* Read Change-Of-State status */
459	irq_status = ioread32(&idio24gpio->reg->cos0_7);
460
461	raw_spin_unlock(&idio24gpio->lock);
462
463	/* Make sure our device generated IRQ */
464	if (!irq_status)
465		return IRQ_NONE;
466
467	/* Handle only unmasked IRQ */
468	irq_mask = idio24gpio->irq_mask & irq_status;
469
470	for_each_set_bit(gpio, &irq_mask, chip->ngpio - 24)
471		generic_handle_domain_irq(chip->irq.domain, gpio + 24);
 
472
473	raw_spin_lock(&idio24gpio->lock);
474
475	/* Clear Change-Of-State status */
476	iowrite32(irq_status, &idio24gpio->reg->cos0_7);
477
478	raw_spin_unlock(&idio24gpio->lock);
479
480	return IRQ_HANDLED;
481}
482
483#define IDIO_24_NGPIO 56
484static const char *idio_24_names[IDIO_24_NGPIO] = {
485	"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
486	"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
487	"OUT16", "OUT17", "OUT18", "OUT19", "OUT20", "OUT21", "OUT22", "OUT23",
488	"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
489	"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15",
490	"IIN16", "IIN17", "IIN18", "IIN19", "IIN20", "IIN21", "IIN22", "IIN23",
491	"TTL0", "TTL1", "TTL2", "TTL3", "TTL4", "TTL5", "TTL6", "TTL7"
492};
493
494static int idio_24_probe(struct pci_dev *pdev, const struct pci_device_id *id)
495{
496	struct device *const dev = &pdev->dev;
497	struct idio_24_gpio *idio24gpio;
498	int err;
499	const size_t pci_plx_bar_index = 1;
500	const size_t pci_bar_index = 2;
501	const char *const name = pci_name(pdev);
502	struct gpio_irq_chip *girq;
503
504	idio24gpio = devm_kzalloc(dev, sizeof(*idio24gpio), GFP_KERNEL);
505	if (!idio24gpio)
506		return -ENOMEM;
507
508	err = pcim_enable_device(pdev);
509	if (err) {
510		dev_err(dev, "Failed to enable PCI device (%d)\n", err);
511		return err;
512	}
513
514	err = pcim_iomap_regions(pdev, BIT(pci_plx_bar_index) | BIT(pci_bar_index), name);
515	if (err) {
516		dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
517		return err;
518	}
519
520	idio24gpio->plx = pcim_iomap_table(pdev)[pci_plx_bar_index];
521	idio24gpio->reg = pcim_iomap_table(pdev)[pci_bar_index];
522
523	idio24gpio->chip.label = name;
524	idio24gpio->chip.parent = dev;
525	idio24gpio->chip.owner = THIS_MODULE;
526	idio24gpio->chip.base = -1;
527	idio24gpio->chip.ngpio = IDIO_24_NGPIO;
528	idio24gpio->chip.names = idio_24_names;
529	idio24gpio->chip.get_direction = idio_24_gpio_get_direction;
530	idio24gpio->chip.direction_input = idio_24_gpio_direction_input;
531	idio24gpio->chip.direction_output = idio_24_gpio_direction_output;
532	idio24gpio->chip.get = idio_24_gpio_get;
533	idio24gpio->chip.get_multiple = idio_24_gpio_get_multiple;
534	idio24gpio->chip.set = idio_24_gpio_set;
535	idio24gpio->chip.set_multiple = idio_24_gpio_set_multiple;
536
537	girq = &idio24gpio->chip.irq;
538	girq->chip = &idio_24_irqchip;
539	/* This will let us handle the parent IRQ in the driver */
540	girq->parent_handler = NULL;
541	girq->num_parents = 0;
542	girq->parents = NULL;
543	girq->default_type = IRQ_TYPE_NONE;
544	girq->handler = handle_edge_irq;
545
546	raw_spin_lock_init(&idio24gpio->lock);
547
548	/* Software board reset */
549	iowrite8(0, &idio24gpio->reg->soft_reset);
550	/*
551	 * enable PLX PEX8311 internal PCI wire interrupt and local interrupt
552	 * input
553	 */
554	iowrite8((INTCSR_INTERNAL_PCI_WIRE | INTCSR_LOCAL_INPUT) >> 8,
555		 idio24gpio->plx + PLX_PEX8311_PCI_LCS_INTCSR + 1);
556
557	err = devm_gpiochip_add_data(dev, &idio24gpio->chip, idio24gpio);
558	if (err) {
559		dev_err(dev, "GPIO registering failed (%d)\n", err);
560		return err;
561	}
562
563	err = devm_request_irq(dev, pdev->irq, idio_24_irq_handler, IRQF_SHARED,
564		name, idio24gpio);
565	if (err) {
566		dev_err(dev, "IRQ handler registering failed (%d)\n", err);
567		return err;
568	}
569
570	return 0;
571}
572
573static const struct pci_device_id idio_24_pci_dev_id[] = {
574	{ PCI_DEVICE(0x494F, 0x0FD0) }, { PCI_DEVICE(0x494F, 0x0BD0) },
575	{ PCI_DEVICE(0x494F, 0x07D0) }, { PCI_DEVICE(0x494F, 0x0FC0) },
576	{ 0 }
577};
578MODULE_DEVICE_TABLE(pci, idio_24_pci_dev_id);
579
580static struct pci_driver idio_24_driver = {
581	.name = "pcie-idio-24",
582	.id_table = idio_24_pci_dev_id,
583	.probe = idio_24_probe
584};
585
586module_pci_driver(idio_24_driver);
587
588MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
589MODULE_DESCRIPTION("ACCES PCIe-IDIO-24 GPIO driver");
590MODULE_LICENSE("GPL v2");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * GPIO driver for the ACCES PCIe-IDIO-24 family
  4 * Copyright (C) 2018 William Breathitt Gray
  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, but
 11 * WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 13 * General Public License for more details.
 14 *
 15 * This driver supports the following ACCES devices: PCIe-IDIO-24,
 16 * PCIe-IDI-24, PCIe-IDO-24, and PCIe-IDIO-12.
 17 */
 18#include <linux/bitmap.h>
 19#include <linux/bitops.h>
 20#include <linux/device.h>
 21#include <linux/errno.h>
 22#include <linux/gpio/driver.h>
 23#include <linux/interrupt.h>
 24#include <linux/irqdesc.h>
 25#include <linux/kernel.h>
 26#include <linux/module.h>
 27#include <linux/pci.h>
 28#include <linux/spinlock.h>
 29#include <linux/types.h>
 30
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31/**
 32 * struct idio_24_gpio_reg - GPIO device registers structure
 33 * @out0_7:	Read: FET Outputs 0-7
 34 *		Write: FET Outputs 0-7
 35 * @out8_15:	Read: FET Outputs 8-15
 36 *		Write: FET Outputs 8-15
 37 * @out16_23:	Read: FET Outputs 16-23
 38 *		Write: FET Outputs 16-23
 39 * @ttl_out0_7:	Read: TTL/CMOS Outputs 0-7
 40 *		Write: TTL/CMOS Outputs 0-7
 41 * @in0_7:	Read: Isolated Inputs 0-7
 42 *		Write: Reserved
 43 * @in8_15:	Read: Isolated Inputs 8-15
 44 *		Write: Reserved
 45 * @in16_23:	Read: Isolated Inputs 16-23
 46 *		Write: Reserved
 47 * @ttl_in0_7:	Read: TTL/CMOS Inputs 0-7
 48 *		Write: Reserved
 49 * @cos0_7:	Read: COS Status Inputs 0-7
 50 *		Write: COS Clear Inputs 0-7
 51 * @cos8_15:	Read: COS Status Inputs 8-15
 52 *		Write: COS Clear Inputs 8-15
 53 * @cos16_23:	Read: COS Status Inputs 16-23
 54 *		Write: COS Clear Inputs 16-23
 55 * @cos_ttl0_7:	Read: COS Status TTL/CMOS 0-7
 56 *		Write: COS Clear TTL/CMOS 0-7
 57 * @ctl:	Read: Control Register
 58 *		Write: Control Register
 59 * @reserved:	Read: Reserved
 60 *		Write: Reserved
 61 * @cos_enable:	Read: COS Enable
 62 *		Write: COS Enable
 63 * @soft_reset:	Read: IRQ Output Pin Status
 64 *		Write: Software Board Reset
 65 */
 66struct idio_24_gpio_reg {
 67	u8 out0_7;
 68	u8 out8_15;
 69	u8 out16_23;
 70	u8 ttl_out0_7;
 71	u8 in0_7;
 72	u8 in8_15;
 73	u8 in16_23;
 74	u8 ttl_in0_7;
 75	u8 cos0_7;
 76	u8 cos8_15;
 77	u8 cos16_23;
 78	u8 cos_ttl0_7;
 79	u8 ctl;
 80	u8 reserved;
 81	u8 cos_enable;
 82	u8 soft_reset;
 83};
 84
 85/**
 86 * struct idio_24_gpio - GPIO device private data structure
 87 * @chip:	instance of the gpio_chip
 88 * @lock:	synchronization lock to prevent I/O race conditions
 89 * @reg:	I/O address offset for the GPIO device registers
 90 * @irq_mask:	I/O bits affected by interrupts
 91 */
 92struct idio_24_gpio {
 93	struct gpio_chip chip;
 94	raw_spinlock_t lock;
 
 95	struct idio_24_gpio_reg __iomem *reg;
 96	unsigned long irq_mask;
 97};
 98
 99static int idio_24_gpio_get_direction(struct gpio_chip *chip,
100	unsigned int offset)
101{
102	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
103	const unsigned long out_mode_mask = BIT(1);
104
105	/* FET Outputs */
106	if (offset < 24)
107		return GPIO_LINE_DIRECTION_OUT;
108
109	/* Isolated Inputs */
110	if (offset < 48)
111		return GPIO_LINE_DIRECTION_IN;
112
113	/* TTL/CMOS I/O */
114	/* OUT MODE = 1 when TTL/CMOS Output Mode is set */
115	if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
116		return GPIO_LINE_DIRECTION_OUT;
117
118	return GPIO_LINE_DIRECTION_IN;
119}
120
121static int idio_24_gpio_direction_input(struct gpio_chip *chip,
122	unsigned int offset)
123{
124	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
125	unsigned long flags;
126	unsigned int ctl_state;
127	const unsigned long out_mode_mask = BIT(1);
128
129	/* TTL/CMOS I/O */
130	if (offset > 47) {
131		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
132
133		/* Clear TTL/CMOS Output Mode */
134		ctl_state = ioread8(&idio24gpio->reg->ctl) & ~out_mode_mask;
135		iowrite8(ctl_state, &idio24gpio->reg->ctl);
136
137		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
138	}
139
140	return 0;
141}
142
143static int idio_24_gpio_direction_output(struct gpio_chip *chip,
144	unsigned int offset, int value)
145{
146	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
147	unsigned long flags;
148	unsigned int ctl_state;
149	const unsigned long out_mode_mask = BIT(1);
150
151	/* TTL/CMOS I/O */
152	if (offset > 47) {
153		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
154
155		/* Set TTL/CMOS Output Mode */
156		ctl_state = ioread8(&idio24gpio->reg->ctl) | out_mode_mask;
157		iowrite8(ctl_state, &idio24gpio->reg->ctl);
158
159		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
160	}
161
162	chip->set(chip, offset, value);
163	return 0;
164}
165
166static int idio_24_gpio_get(struct gpio_chip *chip, unsigned int offset)
167{
168	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
169	const unsigned long offset_mask = BIT(offset % 8);
170	const unsigned long out_mode_mask = BIT(1);
171
172	/* FET Outputs */
173	if (offset < 8)
174		return !!(ioread8(&idio24gpio->reg->out0_7) & offset_mask);
175
176	if (offset < 16)
177		return !!(ioread8(&idio24gpio->reg->out8_15) & offset_mask);
178
179	if (offset < 24)
180		return !!(ioread8(&idio24gpio->reg->out16_23) & offset_mask);
181
182	/* Isolated Inputs */
183	if (offset < 32)
184		return !!(ioread8(&idio24gpio->reg->in0_7) & offset_mask);
185
186	if (offset < 40)
187		return !!(ioread8(&idio24gpio->reg->in8_15) & offset_mask);
188
189	if (offset < 48)
190		return !!(ioread8(&idio24gpio->reg->in16_23) & offset_mask);
191
192	/* TTL/CMOS Outputs */
193	if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
194		return !!(ioread8(&idio24gpio->reg->ttl_out0_7) & offset_mask);
195
196	/* TTL/CMOS Inputs */
197	return !!(ioread8(&idio24gpio->reg->ttl_in0_7) & offset_mask);
198}
199
200static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
201	unsigned long *mask, unsigned long *bits)
202{
203	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
204	unsigned long offset;
205	unsigned long gpio_mask;
206	void __iomem *ports[] = {
207		&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
208		&idio24gpio->reg->out16_23, &idio24gpio->reg->in0_7,
209		&idio24gpio->reg->in8_15, &idio24gpio->reg->in16_23,
210	};
211	size_t index;
212	unsigned long port_state;
213	const unsigned long out_mode_mask = BIT(1);
214
215	/* clear bits array to a clean slate */
216	bitmap_zero(bits, chip->ngpio);
217
218	for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
219		index = offset / 8;
220
221		/* read bits from current gpio port (port 6 is TTL GPIO) */
222		if (index < 6)
223			port_state = ioread8(ports[index]);
224		else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
225			port_state = ioread8(&idio24gpio->reg->ttl_out0_7);
226		else
227			port_state = ioread8(&idio24gpio->reg->ttl_in0_7);
228
229		port_state &= gpio_mask;
230
231		bitmap_set_value8(bits, port_state, offset);
232	}
233
234	return 0;
235}
236
237static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset,
238	int value)
239{
240	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
241	const unsigned long out_mode_mask = BIT(1);
242	void __iomem *base;
243	const unsigned int mask = BIT(offset % 8);
244	unsigned long flags;
245	unsigned int out_state;
246
247	/* Isolated Inputs */
248	if (offset > 23 && offset < 48)
249		return;
250
251	/* TTL/CMOS Inputs */
252	if (offset > 47 && !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask))
253		return;
254
255	/* TTL/CMOS Outputs */
256	if (offset > 47)
257		base = &idio24gpio->reg->ttl_out0_7;
258	/* FET Outputs */
259	else if (offset > 15)
260		base = &idio24gpio->reg->out16_23;
261	else if (offset > 7)
262		base = &idio24gpio->reg->out8_15;
263	else
264		base = &idio24gpio->reg->out0_7;
265
266	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
267
268	if (value)
269		out_state = ioread8(base) | mask;
270	else
271		out_state = ioread8(base) & ~mask;
272
273	iowrite8(out_state, base);
274
275	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
276}
277
278static void idio_24_gpio_set_multiple(struct gpio_chip *chip,
279	unsigned long *mask, unsigned long *bits)
280{
281	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
282	unsigned long offset;
283	unsigned long gpio_mask;
284	void __iomem *ports[] = {
285		&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
286		&idio24gpio->reg->out16_23
287	};
288	size_t index;
289	unsigned long bitmask;
290	unsigned long flags;
291	unsigned long out_state;
292	const unsigned long out_mode_mask = BIT(1);
293
294	for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
295		index = offset / 8;
296
297		bitmask = bitmap_get_value8(bits, offset) & gpio_mask;
298
299		raw_spin_lock_irqsave(&idio24gpio->lock, flags);
300
301		/* read bits from current gpio port (port 6 is TTL GPIO) */
302		if (index < 6) {
303			out_state = ioread8(ports[index]);
304		} else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask) {
305			out_state = ioread8(&idio24gpio->reg->ttl_out0_7);
306		} else {
307			/* skip TTL GPIO if set for input */
308			raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
309			continue;
310		}
311
312		/* set requested bit states */
313		out_state &= ~gpio_mask;
314		out_state |= bitmask;
315
316		/* write bits for current gpio port (port 6 is TTL GPIO) */
317		if (index < 6)
318			iowrite8(out_state, ports[index]);
319		else
320			iowrite8(out_state, &idio24gpio->reg->ttl_out0_7);
321
322		raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
323	}
324}
325
326static void idio_24_irq_ack(struct irq_data *data)
327{
328}
329
330static void idio_24_irq_mask(struct irq_data *data)
331{
332	struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
333	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
334	unsigned long flags;
335	const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
336	unsigned char new_irq_mask;
337	const unsigned long bank_offset = bit_offset/8 * 8;
338	unsigned char cos_enable_state;
339
340	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
341
342	idio24gpio->irq_mask &= BIT(bit_offset);
343	new_irq_mask = idio24gpio->irq_mask >> bank_offset;
344
345	if (!new_irq_mask) {
346		cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
347
348		/* Disable Rising Edge detection */
349		cos_enable_state &= ~BIT(bank_offset);
350		/* Disable Falling Edge detection */
351		cos_enable_state &= ~BIT(bank_offset + 4);
352
353		iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
354	}
355
356	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
357}
358
359static void idio_24_irq_unmask(struct irq_data *data)
360{
361	struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
362	struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
363	unsigned long flags;
364	unsigned char prev_irq_mask;
365	const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
366	const unsigned long bank_offset = bit_offset/8 * 8;
367	unsigned char cos_enable_state;
368
369	raw_spin_lock_irqsave(&idio24gpio->lock, flags);
370
371	prev_irq_mask = idio24gpio->irq_mask >> bank_offset;
372	idio24gpio->irq_mask |= BIT(bit_offset);
373
374	if (!prev_irq_mask) {
375		cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
376
377		/* Enable Rising Edge detection */
378		cos_enable_state |= BIT(bank_offset);
379		/* Enable Falling Edge detection */
380		cos_enable_state |= BIT(bank_offset + 4);
381
382		iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
383	}
384
385	raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
386}
387
388static int idio_24_irq_set_type(struct irq_data *data, unsigned int flow_type)
389{
390	/* The only valid irq types are none and both-edges */
391	if (flow_type != IRQ_TYPE_NONE &&
392		(flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH)
393		return -EINVAL;
394
395	return 0;
396}
397
398static struct irq_chip idio_24_irqchip = {
399	.name = "pcie-idio-24",
400	.irq_ack = idio_24_irq_ack,
401	.irq_mask = idio_24_irq_mask,
402	.irq_unmask = idio_24_irq_unmask,
403	.irq_set_type = idio_24_irq_set_type
404};
405
406static irqreturn_t idio_24_irq_handler(int irq, void *dev_id)
407{
408	struct idio_24_gpio *const idio24gpio = dev_id;
409	unsigned long irq_status;
410	struct gpio_chip *const chip = &idio24gpio->chip;
411	unsigned long irq_mask;
412	int gpio;
413
414	raw_spin_lock(&idio24gpio->lock);
415
416	/* Read Change-Of-State status */
417	irq_status = ioread32(&idio24gpio->reg->cos0_7);
418
419	raw_spin_unlock(&idio24gpio->lock);
420
421	/* Make sure our device generated IRQ */
422	if (!irq_status)
423		return IRQ_NONE;
424
425	/* Handle only unmasked IRQ */
426	irq_mask = idio24gpio->irq_mask & irq_status;
427
428	for_each_set_bit(gpio, &irq_mask, chip->ngpio - 24)
429		generic_handle_irq(irq_find_mapping(chip->irq.domain,
430			gpio + 24));
431
432	raw_spin_lock(&idio24gpio->lock);
433
434	/* Clear Change-Of-State status */
435	iowrite32(irq_status, &idio24gpio->reg->cos0_7);
436
437	raw_spin_unlock(&idio24gpio->lock);
438
439	return IRQ_HANDLED;
440}
441
442#define IDIO_24_NGPIO 56
443static const char *idio_24_names[IDIO_24_NGPIO] = {
444	"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
445	"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
446	"OUT16", "OUT17", "OUT18", "OUT19", "OUT20", "OUT21", "OUT22", "OUT23",
447	"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
448	"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15",
449	"IIN16", "IIN17", "IIN18", "IIN19", "IIN20", "IIN21", "IIN22", "IIN23",
450	"TTL0", "TTL1", "TTL2", "TTL3", "TTL4", "TTL5", "TTL6", "TTL7"
451};
452
453static int idio_24_probe(struct pci_dev *pdev, const struct pci_device_id *id)
454{
455	struct device *const dev = &pdev->dev;
456	struct idio_24_gpio *idio24gpio;
457	int err;
 
458	const size_t pci_bar_index = 2;
459	const char *const name = pci_name(pdev);
460	struct gpio_irq_chip *girq;
461
462	idio24gpio = devm_kzalloc(dev, sizeof(*idio24gpio), GFP_KERNEL);
463	if (!idio24gpio)
464		return -ENOMEM;
465
466	err = pcim_enable_device(pdev);
467	if (err) {
468		dev_err(dev, "Failed to enable PCI device (%d)\n", err);
469		return err;
470	}
471
472	err = pcim_iomap_regions(pdev, BIT(pci_bar_index), name);
473	if (err) {
474		dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
475		return err;
476	}
477
 
478	idio24gpio->reg = pcim_iomap_table(pdev)[pci_bar_index];
479
480	idio24gpio->chip.label = name;
481	idio24gpio->chip.parent = dev;
482	idio24gpio->chip.owner = THIS_MODULE;
483	idio24gpio->chip.base = -1;
484	idio24gpio->chip.ngpio = IDIO_24_NGPIO;
485	idio24gpio->chip.names = idio_24_names;
486	idio24gpio->chip.get_direction = idio_24_gpio_get_direction;
487	idio24gpio->chip.direction_input = idio_24_gpio_direction_input;
488	idio24gpio->chip.direction_output = idio_24_gpio_direction_output;
489	idio24gpio->chip.get = idio_24_gpio_get;
490	idio24gpio->chip.get_multiple = idio_24_gpio_get_multiple;
491	idio24gpio->chip.set = idio_24_gpio_set;
492	idio24gpio->chip.set_multiple = idio_24_gpio_set_multiple;
493
494	girq = &idio24gpio->chip.irq;
495	girq->chip = &idio_24_irqchip;
496	/* This will let us handle the parent IRQ in the driver */
497	girq->parent_handler = NULL;
498	girq->num_parents = 0;
499	girq->parents = NULL;
500	girq->default_type = IRQ_TYPE_NONE;
501	girq->handler = handle_edge_irq;
502
503	raw_spin_lock_init(&idio24gpio->lock);
504
505	/* Software board reset */
506	iowrite8(0, &idio24gpio->reg->soft_reset);
 
 
 
 
 
 
507
508	err = devm_gpiochip_add_data(dev, &idio24gpio->chip, idio24gpio);
509	if (err) {
510		dev_err(dev, "GPIO registering failed (%d)\n", err);
511		return err;
512	}
513
514	err = devm_request_irq(dev, pdev->irq, idio_24_irq_handler, IRQF_SHARED,
515		name, idio24gpio);
516	if (err) {
517		dev_err(dev, "IRQ handler registering failed (%d)\n", err);
518		return err;
519	}
520
521	return 0;
522}
523
524static const struct pci_device_id idio_24_pci_dev_id[] = {
525	{ PCI_DEVICE(0x494F, 0x0FD0) }, { PCI_DEVICE(0x494F, 0x0BD0) },
526	{ PCI_DEVICE(0x494F, 0x07D0) }, { PCI_DEVICE(0x494F, 0x0FC0) },
527	{ 0 }
528};
529MODULE_DEVICE_TABLE(pci, idio_24_pci_dev_id);
530
531static struct pci_driver idio_24_driver = {
532	.name = "pcie-idio-24",
533	.id_table = idio_24_pci_dev_id,
534	.probe = idio_24_probe
535};
536
537module_pci_driver(idio_24_driver);
538
539MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
540MODULE_DESCRIPTION("ACCES PCIe-IDIO-24 GPIO driver");
541MODULE_LICENSE("GPL v2");