1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Linux multi-function-device driver (MFD) for the integrated peripherals 4 * of the VIA VX855 chipset 5 * 6 * Copyright (C) 2009 VIA Technologies, Inc. 7 * Copyright (C) 2010 One Laptop per Child 8 * 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 containing 20 * the power management IO space base */ 21 #define VX855_CFG_PMIO_OFFSET 0x88 22 23 /* ACPI I/O Space registers */ 24 #define VX855_PMIO_ACPI 0x00 25 #define VX855_PMIO_ACPI_LEN 0x0b 26 27 /* Processor Power Management */ 28 #define VX855_PMIO_PPM 0x10 29 #define VX855_PMIO_PPM_LEN 0x08 30 31 /* General Purpose Power Management */ 32 #define VX855_PMIO_GPPM 0x20 33 #define VX855_PMIO_R_GPI 0x48 34 #define VX855_PMIO_R_GPO 0x4c 35 #define VX855_PMIO_GPPM_LEN 0x33 36 37 #define VSPIC_MMIO_SIZE 0x1000 38 39 static struct resource vx855_gpio_resources[] = { 40 { 41 .flags = IORESOURCE_IO, 42 }, 43 { 44 .flags = IORESOURCE_IO, 45 }, 46 }; 47 48 static 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 in 55 * the vx855_gpio driver */ 56 .ignore_resource_conflicts = true, 57 }, 58 }; 59 60 static 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, but 79 * hardware returns them as 0x01 */ 80 gpio_io_offset &= 0xff80; 81 82 /* As the region identified here includes many non-GPIO things, we 83 * 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 other 93 * drivers like old, not-yet-platform_device ported i2c-viapro */ 94 return -ENODEV; 95 out: 96 pci_disable_device(pdev); 97 return ret; 98 } 99 100 static void vx855_remove(struct pci_dev *pdev) 101 { 102 mfd_remove_devices(&pdev->dev); 103 pci_disable_device(pdev); 104 } 105 106 static const struct pci_device_id vx855_pci_tbl[] = { 107 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX855) }, 108 { 0, } 109 }; 110 MODULE_DEVICE_TABLE(pci, vx855_pci_tbl); 111 112 static struct pci_driver vx855_pci_driver = { 113 .name = "vx855", 114 .id_table = vx855_pci_tbl, 115 .probe = vx855_probe, 116 .remove = vx855_remove, 117 }; 118 119 module_pci_driver(vx855_pci_driver); 120 121 MODULE_LICENSE("GPL"); 122 MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>"); 123 MODULE_DESCRIPTION("Driver for the VIA VX855 chipset"); 124