1 // SPDX-License-Identifier: GPL-2.0-only 2 /* sun_uflash.c - Driver for user-programmable flash on 3 * Sun Microsystems SME boardsets. 4 * 5 * This driver does NOT provide access to the OBP-flash for 6 * safety reasons-- use <linux>/drivers/sbus/char/flash.c instead. 7 * 8 * Copyright (c) 2001 Eric Brower (ebrower@usa.net) 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/fs.h> 14 #include <linux/errno.h> 15 #include <linux/ioport.h> 16 #include <linux/of.h> 17 #include <linux/of_device.h> 18 #include <linux/slab.h> 19 #include <asm/prom.h> 20 #include <linux/uaccess.h> 21 #include <asm/io.h> 22 23 #include <linux/mtd/mtd.h> 24 #include <linux/mtd/map.h> 25 26 #define UFLASH_OBPNAME "flashprom" 27 #define DRIVER_NAME "sun_uflash" 28 #define PFX DRIVER_NAME ": " 29 30 #define UFLASH_WINDOW_SIZE 0x200000 31 #define UFLASH_BUSWIDTH 1 /* EBus is 8-bit */ 32 33 MODULE_AUTHOR("Eric Brower <ebrower@usa.net>"); 34 MODULE_DESCRIPTION("User-programmable flash device on Sun Microsystems boardsets"); 35 MODULE_LICENSE("GPL"); 36 MODULE_VERSION("2.1"); 37 38 struct uflash_dev { 39 const char *name; /* device name */ 40 struct map_info map; /* mtd map info */ 41 struct mtd_info *mtd; /* mtd info */ 42 }; 43 44 struct map_info uflash_map_templ = { 45 .name = "SUNW,???-????", 46 .size = UFLASH_WINDOW_SIZE, 47 .bankwidth = UFLASH_BUSWIDTH, 48 }; 49 50 int uflash_devinit(struct platform_device *op, struct device_node *dp) 51 { 52 struct uflash_dev *up; 53 54 if (op->resource[1].flags) { 55 /* Non-CFI userflash device-- once I find one we 56 * can work on supporting it. 57 */ 58 printk(KERN_ERR PFX "Unsupported device at %pOF, 0x%llx\n", 59 dp, (unsigned long long)op->resource[0].start); 60 61 return -ENODEV; 62 } 63 64 up = kzalloc(sizeof(struct uflash_dev), GFP_KERNEL); 65 if (!up) 66 return -ENOMEM; 67 68 /* copy defaults and tweak parameters */ 69 memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ)); 70 71 up->map.size = resource_size(&op->resource[0]); 72 73 up->name = of_get_property(dp, "model", NULL); 74 if (up->name && 0 < strlen(up->name)) 75 up->map.name = up->name; 76 77 up->map.phys = op->resource[0].start; 78 79 up->map.virt = of_ioremap(&op->resource[0], 0, up->map.size, 80 DRIVER_NAME); 81 if (!up->map.virt) { 82 printk(KERN_ERR PFX "Failed to map device.\n"); 83 kfree(up); 84 85 return -EINVAL; 86 } 87 88 simple_map_init(&up->map); 89 90 /* MTD registration */ 91 up->mtd = do_map_probe("cfi_probe", &up->map); 92 if (!up->mtd) { 93 of_iounmap(&op->resource[0], up->map.virt, up->map.size); 94 kfree(up); 95 96 return -ENXIO; 97 } 98 99 up->mtd->owner = THIS_MODULE; 100 101 mtd_device_register(up->mtd, NULL, 0); 102 103 dev_set_drvdata(&op->dev, up); 104 105 return 0; 106 } 107 108 static int uflash_probe(struct platform_device *op) 109 { 110 struct device_node *dp = op->dev.of_node; 111 112 /* Flashprom must have the "user" property in order to 113 * be used by this driver. 114 */ 115 if (!of_find_property(dp, "user", NULL)) 116 return -ENODEV; 117 118 return uflash_devinit(op, dp); 119 } 120 121 static int uflash_remove(struct platform_device *op) 122 { 123 struct uflash_dev *up = dev_get_drvdata(&op->dev); 124 125 if (up->mtd) { 126 mtd_device_unregister(up->mtd); 127 map_destroy(up->mtd); 128 } 129 if (up->map.virt) { 130 of_iounmap(&op->resource[0], up->map.virt, up->map.size); 131 up->map.virt = NULL; 132 } 133 134 kfree(up); 135 136 return 0; 137 } 138 139 static const struct of_device_id uflash_match[] = { 140 { 141 .name = UFLASH_OBPNAME, 142 }, 143 {}, 144 }; 145 146 MODULE_DEVICE_TABLE(of, uflash_match); 147 148 static struct platform_driver uflash_driver = { 149 .driver = { 150 .name = DRIVER_NAME, 151 .of_match_table = uflash_match, 152 }, 153 .probe = uflash_probe, 154 .remove = uflash_remove, 155 }; 156 157 module_platform_driver(uflash_driver); 158