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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Linux multi-function-device driver (MFD) for the integrated peripherals4 * of the VIA VX855 chipset5 *6 * Copyright (C) 2009 VIA Technologies, Inc.7 * Copyright (C) 2010 One Laptop per Child8 * Author: Harald Welte <HaraldWelte@viatech.com>9 * All rights reserved.10 */11 12#include <linux/kernel.h>13#include <linux/module.h>14#include <linux/device.h>15#include <linux/platform_device.h>16#include <linux/pci.h>17#include <linux/mfd/core.h>18 19/* offset into pci config space indicating the 16bit register containing20 * the power management IO space base */21#define VX855_CFG_PMIO_OFFSET 0x8822 23/* ACPI I/O Space registers */24#define VX855_PMIO_ACPI 0x0025#define VX855_PMIO_ACPI_LEN 0x0b26 27/* Processor Power Management */28#define VX855_PMIO_PPM 0x1029#define VX855_PMIO_PPM_LEN 0x0830 31/* General Purpose Power Management */32#define VX855_PMIO_GPPM 0x2033#define VX855_PMIO_R_GPI 0x4834#define VX855_PMIO_R_GPO 0x4c35#define VX855_PMIO_GPPM_LEN 0x3336 37#define VSPIC_MMIO_SIZE 0x100038 39static struct resource vx855_gpio_resources[] = {40 {41 .flags = IORESOURCE_IO,42 },43 {44 .flags = IORESOURCE_IO,45 },46};47 48static const struct mfd_cell vx855_cells[] = {49 {50 .name = "vx855_gpio",51 .num_resources = ARRAY_SIZE(vx855_gpio_resources),52 .resources = vx855_gpio_resources,53 54 /* we must ignore resource conflicts, for reasons outlined in55 * the vx855_gpio driver */56 .ignore_resource_conflicts = true,57 },58};59 60static int vx855_probe(struct pci_dev *pdev,61 const struct pci_device_id *id)62{63 int ret;64 u16 gpio_io_offset;65 66 ret = pci_enable_device(pdev);67 if (ret)68 return -ENODEV;69 70 pci_read_config_word(pdev, VX855_CFG_PMIO_OFFSET, &gpio_io_offset);71 if (!gpio_io_offset) {72 dev_warn(&pdev->dev,73 "BIOS did not assign PMIO base offset?!?\n");74 ret = -ENODEV;75 goto out;76 }77 78 /* mask out the lowest seven bits, as they are always zero, but79 * hardware returns them as 0x01 */80 gpio_io_offset &= 0xff80;81 82 /* As the region identified here includes many non-GPIO things, we83 * only work with the specific registers that concern us. */84 vx855_gpio_resources[0].start = gpio_io_offset + VX855_PMIO_R_GPI;85 vx855_gpio_resources[0].end = vx855_gpio_resources[0].start + 3;86 vx855_gpio_resources[1].start = gpio_io_offset + VX855_PMIO_R_GPO;87 vx855_gpio_resources[1].end = vx855_gpio_resources[1].start + 3;88 89 ret = mfd_add_devices(&pdev->dev, -1, vx855_cells, ARRAY_SIZE(vx855_cells),90 NULL, 0, NULL);91 92 /* we always return -ENODEV here in order to enable other93 * drivers like old, not-yet-platform_device ported i2c-viapro */94 return -ENODEV;95out:96 pci_disable_device(pdev);97 return ret;98}99 100static void vx855_remove(struct pci_dev *pdev)101{102 mfd_remove_devices(&pdev->dev);103 pci_disable_device(pdev);104}105 106static const struct pci_device_id vx855_pci_tbl[] = {107 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX855) },108 { 0, }109};110MODULE_DEVICE_TABLE(pci, vx855_pci_tbl);111 112static struct pci_driver vx855_pci_driver = {113 .name = "vx855",114 .id_table = vx855_pci_tbl,115 .probe = vx855_probe,116 .remove = vx855_remove,117};118 119module_pci_driver(vx855_pci_driver);120 121MODULE_LICENSE("GPL");122MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>");123MODULE_DESCRIPTION("Driver for the VIA VX855 chipset");124