drivers/gpio/gpio-pci-idio-16.c

   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
  18 static const struct regmap_range idio_16_wr_ranges[] = {
  19         regmap_reg_range(0x0, 0x2), regmap_reg_range(0x3, 0x4),
  20 };
  21 static const struct regmap_range idio_16_rd_ranges[] = {
  22         regmap_reg_range(0x1, 0x2), regmap_reg_range(0x5, 0x6),
  23 };
  24 static const struct regmap_range idio_16_precious_ranges[] = {
  25         regmap_reg_range(0x2, 0x2),
  26 };
  27 static 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 };
  31 static 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 };
  35 static 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 };
  39 static 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
  59 static 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
  68 static 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         struct idio_16_regmap_config config = {};
  74         void __iomem *regs;
  75         struct regmap *map;
  76
  77         err = pcim_enable_device(pdev);
  78         if (err)
  79                 return dev_err_probe(dev, err, "Failed to enable PCI device\n");
  80
  81         regs = pcim_iomap_region(pdev, pci_bar_index, pci_name(pdev));
  82         if (IS_ERR(regs))
  83                 return dev_err_probe(dev, PTR_ERR(regs), "Unable to map PCI I/O addresses\n");
  84
  85         map = devm_regmap_init_mmio(dev, regs, &idio_16_regmap_config);
  86         if (IS_ERR(map))
  87                 return dev_err_probe(dev, PTR_ERR(map), "Unable to initialize register map\n");
  88
  89         config.parent = dev;
  90         config.map = map;
  91         config.regmap_irqs = idio_16_regmap_irqs;
  92         config.num_regmap_irqs = ARRAY_SIZE(idio_16_regmap_irqs);
  93         config.irq = pdev->irq;
  94         config.filters = true;
  95
  96         return devm_idio_16_regmap_register(dev, &config);
  97 }
  98
  99 static const struct pci_device_id idio_16_pci_dev_id[] = {
 100         { PCI_DEVICE(0x494F, 0x0DC8) }, { 0 }
 101 };
 102 MODULE_DEVICE_TABLE(pci, idio_16_pci_dev_id);
 103
 104 static struct pci_driver idio_16_driver = {
 105         .name = "pci-idio-16",
 106         .id_table = idio_16_pci_dev_id,
 107         .probe = idio_16_probe
 108 };
 109
 110 module_pci_driver(idio_16_driver);
 111
 112 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
 113 MODULE_DESCRIPTION("ACCES PCI-IDIO-16 GPIO driver");
 114 MODULE_LICENSE("GPL v2");
 115 MODULE_IMPORT_NS("GPIO_IDIO_16");