1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * GPIO driver for the ACCES PCI-IDIO-16
  4 * Copyright (C) 2017 William Breathitt Gray
  5 */
  6#include <linux/bits.h>
  7#include <linux/device.h>
  8#include <linux/err.h>
  9#include <linux/irq.h>
 10#include <linux/kernel.h>
 11#include <linux/module.h>
 12#include <linux/pci.h>
 13#include <linux/regmap.h>
 14#include <linux/types.h>
 15
 16#include "gpio-idio-16.h"
 17
 18static const struct regmap_range idio_16_wr_ranges[] = {
 19	regmap_reg_range(0x0, 0x2), regmap_reg_range(0x3, 0x4),
 20};
 21static const struct regmap_range idio_16_rd_ranges[] = {
 22	regmap_reg_range(0x1, 0x2), regmap_reg_range(0x5, 0x6),
 23};
 24static const struct regmap_range idio_16_precious_ranges[] = {
 25	regmap_reg_range(0x2, 0x2),
 26};
 27static const struct regmap_access_table idio_16_wr_table = {
 28	.yes_ranges = idio_16_wr_ranges,
 29	.n_yes_ranges = ARRAY_SIZE(idio_16_wr_ranges),
 30};
 31static const struct regmap_access_table idio_16_rd_table = {
 32	.yes_ranges = idio_16_rd_ranges,
 33	.n_yes_ranges = ARRAY_SIZE(idio_16_rd_ranges),
 34};
 35static const struct regmap_access_table idio_16_precious_table = {
 36	.yes_ranges = idio_16_precious_ranges,
 37	.n_yes_ranges = ARRAY_SIZE(idio_16_precious_ranges),
 38};
 39static const struct regmap_config idio_16_regmap_config = {
 40	.reg_bits = 8,
 41	.reg_stride = 1,
 42	.val_bits = 8,
 43	.io_port = true,
 44	.wr_table = &idio_16_wr_table,
 45	.rd_table = &idio_16_rd_table,
 46	.volatile_table = &idio_16_rd_table,
 47	.precious_table = &idio_16_precious_table,
 48	.cache_type = REGCACHE_FLAT,
 49	.use_raw_spinlock = true,
 50};
 51
 52/* Only input lines (GPIO 16-31) support interrupts */
 53#define IDIO_16_REGMAP_IRQ(_id)						\
 54	[16 + _id] = {							\
 55		.mask = BIT(2),						\
 56		.type = { .types_supported = IRQ_TYPE_EDGE_BOTH },	\
 57	}
 58
 59static const struct regmap_irq idio_16_regmap_irqs[] = {
 60	IDIO_16_REGMAP_IRQ(0), IDIO_16_REGMAP_IRQ(1), IDIO_16_REGMAP_IRQ(2), /* 0-2 */
 61	IDIO_16_REGMAP_IRQ(3), IDIO_16_REGMAP_IRQ(4), IDIO_16_REGMAP_IRQ(5), /* 3-5 */
 62	IDIO_16_REGMAP_IRQ(6), IDIO_16_REGMAP_IRQ(7), IDIO_16_REGMAP_IRQ(8), /* 6-8 */
 63	IDIO_16_REGMAP_IRQ(9), IDIO_16_REGMAP_IRQ(10), IDIO_16_REGMAP_IRQ(11), /* 9-11 */
 64	IDIO_16_REGMAP_IRQ(12), IDIO_16_REGMAP_IRQ(13), IDIO_16_REGMAP_IRQ(14), /* 12-14 */
 65	IDIO_16_REGMAP_IRQ(15), /* 15 */
 66};
 67
 68static int idio_16_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 69{
 70	struct device *const dev = &pdev->dev;
 71	int err;
 72	const size_t pci_bar_index = 2;
 73	const char *const name = pci_name(pdev);
 74	struct idio_16_regmap_config config = {};
 75	void __iomem *regs;
 76	struct regmap *map;
 77
 78	err = pcim_enable_device(pdev);
 79	if (err) {
 80		dev_err(dev, "Failed to enable PCI device (%d)\n", err);
 81		return err;
 82	}
 83
 84	err = pcim_iomap_regions(pdev, BIT(pci_bar_index), name);
 85	if (err) {
 86		dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
 87		return err;
 88	}
 89
 90	regs = pcim_iomap_table(pdev)[pci_bar_index];
 91
 92	map = devm_regmap_init_mmio(dev, regs, &idio_16_regmap_config);
 93	if (IS_ERR(map))
 94		return dev_err_probe(dev, PTR_ERR(map), "Unable to initialize register map\n");
 95
 96	config.parent = dev;
 97	config.map = map;
 98	config.regmap_irqs = idio_16_regmap_irqs;
 99	config.num_regmap_irqs = ARRAY_SIZE(idio_16_regmap_irqs);
100	config.irq = pdev->irq;
101	config.filters = true;
102
103	return devm_idio_16_regmap_register(dev, &config);
104}
105
106static const struct pci_device_id idio_16_pci_dev_id[] = {
107	{ PCI_DEVICE(0x494F, 0x0DC8) }, { 0 }
108};
109MODULE_DEVICE_TABLE(pci, idio_16_pci_dev_id);
110
111static struct pci_driver idio_16_driver = {
112	.name = "pci-idio-16",
113	.id_table = idio_16_pci_dev_id,
114	.probe = idio_16_probe
115};
116
117module_pci_driver(idio_16_driver);
118
119MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
120MODULE_DESCRIPTION("ACCES PCI-IDIO-16 GPIO driver");
121MODULE_LICENSE("GPL v2");
122MODULE_IMPORT_NS(GPIO_IDIO_16);