1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Virtual EISA root driver. 4 * Acts as a placeholder if we don't have a proper EISA bridge. 5 * 6 * (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org> 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/platform_device.h> 11 #include <linux/eisa.h> 12 #include <linux/module.h> 13 #include <linux/moduleparam.h> 14 #include <linux/init.h> 15 16 #if defined(CONFIG_EISA_VLB_PRIMING) 17 #define EISA_FORCE_PROBE_DEFAULT 1 18 #else 19 #define EISA_FORCE_PROBE_DEFAULT 0 20 #endif 21 22 static int force_probe = EISA_FORCE_PROBE_DEFAULT; 23 static void virtual_eisa_release (struct device *); 24 25 /* The default EISA device parent (virtual root device). 26 * Now use a platform device, since that's the obvious choice. */ 27 28 static struct platform_device eisa_root_dev = { 29 .name = "eisa", 30 .id = 0, 31 .dev = { 32 .release = virtual_eisa_release, 33 }, 34 }; 35 36 static struct eisa_root_device eisa_bus_root = { 37 .dev = &eisa_root_dev.dev, 38 .bus_base_addr = 0, 39 .res = &ioport_resource, 40 .slots = EISA_MAX_SLOTS, 41 .dma_mask = 0xffffffff, 42 }; 43 44 static void virtual_eisa_release (struct device *dev) 45 { 46 /* nothing really to do here */ 47 } 48 49 static int __init virtual_eisa_root_init (void) 50 { 51 int r; 52 53 if ((r = platform_device_register (&eisa_root_dev))) 54 return r; 55 56 eisa_bus_root.force_probe = force_probe; 57 58 dev_set_drvdata(&eisa_root_dev.dev, &eisa_bus_root); 59 60 if (eisa_root_register (&eisa_bus_root)) { 61 /* A real bridge may have been registered before 62 * us. So quietly unregister. */ 63 platform_device_unregister (&eisa_root_dev); 64 return -1; 65 } 66 67 return 0; 68 } 69 70 module_param (force_probe, int, 0444); 71 72 device_initcall (virtual_eisa_root_init); 73