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_SUPPORTED_DEVICE(DRIVER_NAME); 36 MODULE_LICENSE("GPL"); 37 MODULE_VERSION("2.1"); 38 39 struct uflash_dev { 40 const char *name; /* device name */ 41 struct map_info map; /* mtd map info */ 42 struct mtd_info *mtd; /* mtd info */ 43 }; 44 45 struct map_info uflash_map_templ = { 46 .name = "SUNW,???-????", 47 .size = UFLASH_WINDOW_SIZE, 48 .bankwidth = UFLASH_BUSWIDTH, 49 }; 50 51 int uflash_devinit(struct platform_device *op, struct device_node *dp) 52 { 53 struct uflash_dev *up; 54 55 if (op->resource[1].flags) { 56 /* Non-CFI userflash device-- once I find one we 57 * can work on supporting it. 58 */ 59 printk(KERN_ERR PFX "Unsupported device at %pOF, 0x%llx\n", 60 dp, (unsigned long long)op->resource[0].start); 61 62 return -ENODEV; 63 } 64 65 up = kzalloc(sizeof(struct uflash_dev), GFP_KERNEL); 66 if (!up) { 67 printk(KERN_ERR PFX "Cannot allocate struct uflash_dev\n"); 68 return -ENOMEM; 69 } 70 71 /* copy defaults and tweak parameters */ 72 memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ)); 73 74 up->map.size = resource_size(&op->resource[0]); 75 76 up->name = of_get_property(dp, "model", NULL); 77 if (up->name && 0 < strlen(up->name)) 78 up->map.name = up->name; 79 80 up->map.phys = op->resource[0].start; 81 82 up->map.virt = of_ioremap(&op->resource[0], 0, up->map.size, 83 DRIVER_NAME); 84 if (!up->map.virt) { 85 printk(KERN_ERR PFX "Failed to map device.\n"); 86 kfree(up); 87 88 return -EINVAL; 89 } 90 91 simple_map_init(&up->map); 92 93 /* MTD registration */ 94 up->mtd = do_map_probe("cfi_probe", &up->map); 95 if (!up->mtd) { 96 of_iounmap(&op->resource[0], up->map.virt, up->map.size); 97 kfree(up); 98 99 return -ENXIO; 100 } 101 102 up->mtd->owner = THIS_MODULE; 103 104 mtd_device_register(up->mtd, NULL, 0); 105 106 dev_set_drvdata(&op->dev, up); 107 108 return 0; 109 } 110 111 static int uflash_probe(struct platform_device *op) 112 { 113 struct device_node *dp = op->dev.of_node; 114 115 /* Flashprom must have the "user" property in order to 116 * be used by this driver. 117 */ 118 if (!of_find_property(dp, "user", NULL)) 119 return -ENODEV; 120 121 return uflash_devinit(op, dp); 122 } 123 124 static int uflash_remove(struct platform_device *op) 125 { 126 struct uflash_dev *up = dev_get_drvdata(&op->dev); 127 128 if (up->mtd) { 129 mtd_device_unregister(up->mtd); 130 map_destroy(up->mtd); 131 } 132 if (up->map.virt) { 133 of_iounmap(&op->resource[0], up->map.virt, up->map.size); 134 up->map.virt = NULL; 135 } 136 137 kfree(up); 138 139 return 0; 140 } 141 142 static const struct of_device_id uflash_match[] = { 143 { 144 .name = UFLASH_OBPNAME, 145 }, 146 {}, 147 }; 148 149 MODULE_DEVICE_TABLE(of, uflash_match); 150 151 static struct platform_driver uflash_driver = { 152 .driver = { 153 .name = DRIVER_NAME, 154 .of_match_table = uflash_match, 155 }, 156 .probe = uflash_probe, 157 .remove = uflash_remove, 158 }; 159 160 module_platform_driver(uflash_driver); 161