|  | /* | 
|  | * Flash mappings described by the OF (or flattened) device tree | 
|  | * | 
|  | * Copyright (C) 2006 MontaVista Software Inc. | 
|  | * Author: Vitaly Wool <vwool@ru.mvista.com> | 
|  | * | 
|  | * Revised to handle newer style flash binding by: | 
|  | *   Copyright (C) 2007 David Gibson, IBM Corporation. | 
|  | * | 
|  | * This program is free software; you can redistribute  it and/or modify it | 
|  | * under  the terms of  the GNU General  Public License as published by the | 
|  | * Free Software Foundation;  either version 2 of the  License, or (at your | 
|  | * option) any later version. | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/device.h> | 
|  | #include <linux/mtd/mtd.h> | 
|  | #include <linux/mtd/map.h> | 
|  | #include <linux/mtd/partitions.h> | 
|  | #include <linux/mtd/concat.h> | 
|  | #include <linux/of.h> | 
|  | #include <linux/of_address.h> | 
|  | #include <linux/of_platform.h> | 
|  | #include <linux/slab.h> | 
|  |  | 
|  | struct of_flash_list { | 
|  | struct mtd_info *mtd; | 
|  | struct map_info map; | 
|  | struct resource *res; | 
|  | }; | 
|  |  | 
|  | struct of_flash { | 
|  | struct mtd_info		*cmtd; | 
|  | int list_size; /* number of elements in of_flash_list */ | 
|  | struct of_flash_list	list[0]; | 
|  | }; | 
|  |  | 
|  | static int of_flash_remove(struct platform_device *dev) | 
|  | { | 
|  | struct of_flash *info; | 
|  | int i; | 
|  |  | 
|  | info = dev_get_drvdata(&dev->dev); | 
|  | if (!info) | 
|  | return 0; | 
|  | dev_set_drvdata(&dev->dev, NULL); | 
|  |  | 
|  | if (info->cmtd != info->list[0].mtd) { | 
|  | mtd_device_unregister(info->cmtd); | 
|  | mtd_concat_destroy(info->cmtd); | 
|  | } | 
|  |  | 
|  | if (info->cmtd) | 
|  | mtd_device_unregister(info->cmtd); | 
|  |  | 
|  | for (i = 0; i < info->list_size; i++) { | 
|  | if (info->list[i].mtd) | 
|  | map_destroy(info->list[i].mtd); | 
|  |  | 
|  | if (info->list[i].map.virt) | 
|  | iounmap(info->list[i].map.virt); | 
|  |  | 
|  | if (info->list[i].res) { | 
|  | release_resource(info->list[i].res); | 
|  | kfree(info->list[i].res); | 
|  | } | 
|  | } | 
|  |  | 
|  | kfree(info); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Helper function to handle probing of the obsolete "direct-mapped" | 
|  | * compatible binding, which has an extra "probe-type" property | 
|  | * describing the type of flash probe necessary. */ | 
|  | static struct mtd_info * __devinit obsolete_probe(struct platform_device *dev, | 
|  | struct map_info *map) | 
|  | { | 
|  | struct device_node *dp = dev->dev.of_node; | 
|  | const char *of_probe; | 
|  | struct mtd_info *mtd; | 
|  | static const char *rom_probe_types[] | 
|  | = { "cfi_probe", "jedec_probe", "map_rom"}; | 
|  | int i; | 
|  |  | 
|  | dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" " | 
|  | "flash binding\n"); | 
|  |  | 
|  | of_probe = of_get_property(dp, "probe-type", NULL); | 
|  | if (!of_probe) { | 
|  | for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) { | 
|  | mtd = do_map_probe(rom_probe_types[i], map); | 
|  | if (mtd) | 
|  | return mtd; | 
|  | } | 
|  | return NULL; | 
|  | } else if (strcmp(of_probe, "CFI") == 0) { | 
|  | return do_map_probe("cfi_probe", map); | 
|  | } else if (strcmp(of_probe, "JEDEC") == 0) { | 
|  | return do_map_probe("jedec_probe", map); | 
|  | } else { | 
|  | if (strcmp(of_probe, "ROM") != 0) | 
|  | dev_warn(&dev->dev, "obsolete_probe: don't know probe " | 
|  | "type '%s', mapping as rom\n", of_probe); | 
|  | return do_map_probe("mtd_rom", map); | 
|  | } | 
|  | } | 
|  |  | 
|  | /* When partitions are set we look for a linux,part-probe property which | 
|  | specifies the list of partition probers to use. If none is given then the | 
|  | default is use. These take precedence over other device tree | 
|  | information. */ | 
|  | static const char *part_probe_types_def[] = { "cmdlinepart", "RedBoot", | 
|  | "ofpart", "ofoldpart", NULL }; | 
|  | static const char ** __devinit of_get_probes(struct device_node *dp) | 
|  | { | 
|  | const char *cp; | 
|  | int cplen; | 
|  | unsigned int l; | 
|  | unsigned int count; | 
|  | const char **res; | 
|  |  | 
|  | cp = of_get_property(dp, "linux,part-probe", &cplen); | 
|  | if (cp == NULL) | 
|  | return part_probe_types_def; | 
|  |  | 
|  | count = 0; | 
|  | for (l = 0; l != cplen; l++) | 
|  | if (cp[l] == 0) | 
|  | count++; | 
|  |  | 
|  | res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL); | 
|  | count = 0; | 
|  | while (cplen > 0) { | 
|  | res[count] = cp; | 
|  | l = strlen(cp) + 1; | 
|  | cp += l; | 
|  | cplen -= l; | 
|  | count++; | 
|  | } | 
|  | return res; | 
|  | } | 
|  |  | 
|  | static void __devinit of_free_probes(const char **probes) | 
|  | { | 
|  | if (probes != part_probe_types_def) | 
|  | kfree(probes); | 
|  | } | 
|  |  | 
|  | static struct of_device_id of_flash_match[]; | 
|  | static int __devinit of_flash_probe(struct platform_device *dev) | 
|  | { | 
|  | const char **part_probe_types; | 
|  | const struct of_device_id *match; | 
|  | struct device_node *dp = dev->dev.of_node; | 
|  | struct resource res; | 
|  | struct of_flash *info; | 
|  | const char *probe_type; | 
|  | const __be32 *width; | 
|  | int err; | 
|  | int i; | 
|  | int count; | 
|  | const __be32 *p; | 
|  | int reg_tuple_size; | 
|  | struct mtd_info **mtd_list = NULL; | 
|  | resource_size_t res_size; | 
|  | struct mtd_part_parser_data ppdata; | 
|  |  | 
|  | match = of_match_device(of_flash_match, &dev->dev); | 
|  | if (!match) | 
|  | return -EINVAL; | 
|  | probe_type = match->data; | 
|  |  | 
|  | reg_tuple_size = (of_n_addr_cells(dp) + of_n_size_cells(dp)) * sizeof(u32); | 
|  |  | 
|  | /* | 
|  | * Get number of "reg" tuples. Scan for MTD devices on area's | 
|  | * described by each "reg" region. This makes it possible (including | 
|  | * the concat support) to support the Intel P30 48F4400 chips which | 
|  | * consists internally of 2 non-identical NOR chips on one die. | 
|  | */ | 
|  | p = of_get_property(dp, "reg", &count); | 
|  | if (count % reg_tuple_size != 0) { | 
|  | dev_err(&dev->dev, "Malformed reg property on %s\n", | 
|  | dev->dev.of_node->full_name); | 
|  | err = -EINVAL; | 
|  | goto err_flash_remove; | 
|  | } | 
|  | count /= reg_tuple_size; | 
|  |  | 
|  | err = -ENOMEM; | 
|  | info = kzalloc(sizeof(struct of_flash) + | 
|  | sizeof(struct of_flash_list) * count, GFP_KERNEL); | 
|  | if (!info) | 
|  | goto err_flash_remove; | 
|  |  | 
|  | dev_set_drvdata(&dev->dev, info); | 
|  |  | 
|  | mtd_list = kzalloc(sizeof(*mtd_list) * count, GFP_KERNEL); | 
|  | if (!mtd_list) | 
|  | goto err_flash_remove; | 
|  |  | 
|  | for (i = 0; i < count; i++) { | 
|  | err = -ENXIO; | 
|  | if (of_address_to_resource(dp, i, &res)) { | 
|  | /* | 
|  | * Continue with next register tuple if this | 
|  | * one is not mappable | 
|  | */ | 
|  | continue; | 
|  | } | 
|  |  | 
|  | dev_dbg(&dev->dev, "of_flash device: %pR\n", &res); | 
|  |  | 
|  | err = -EBUSY; | 
|  | res_size = resource_size(&res); | 
|  | info->list[i].res = request_mem_region(res.start, res_size, | 
|  | dev_name(&dev->dev)); | 
|  | if (!info->list[i].res) | 
|  | goto err_out; | 
|  |  | 
|  | err = -ENXIO; | 
|  | width = of_get_property(dp, "bank-width", NULL); | 
|  | if (!width) { | 
|  | dev_err(&dev->dev, "Can't get bank width from device" | 
|  | " tree\n"); | 
|  | goto err_out; | 
|  | } | 
|  |  | 
|  | info->list[i].map.name = dev_name(&dev->dev); | 
|  | info->list[i].map.phys = res.start; | 
|  | info->list[i].map.size = res_size; | 
|  | info->list[i].map.bankwidth = be32_to_cpup(width); | 
|  |  | 
|  | err = -ENOMEM; | 
|  | info->list[i].map.virt = ioremap(info->list[i].map.phys, | 
|  | info->list[i].map.size); | 
|  | if (!info->list[i].map.virt) { | 
|  | dev_err(&dev->dev, "Failed to ioremap() flash" | 
|  | " region\n"); | 
|  | goto err_out; | 
|  | } | 
|  |  | 
|  | simple_map_init(&info->list[i].map); | 
|  |  | 
|  | if (probe_type) { | 
|  | info->list[i].mtd = do_map_probe(probe_type, | 
|  | &info->list[i].map); | 
|  | } else { | 
|  | info->list[i].mtd = obsolete_probe(dev, | 
|  | &info->list[i].map); | 
|  | } | 
|  | mtd_list[i] = info->list[i].mtd; | 
|  |  | 
|  | err = -ENXIO; | 
|  | if (!info->list[i].mtd) { | 
|  | dev_err(&dev->dev, "do_map_probe() failed\n"); | 
|  | goto err_out; | 
|  | } else { | 
|  | info->list_size++; | 
|  | } | 
|  | info->list[i].mtd->owner = THIS_MODULE; | 
|  | info->list[i].mtd->dev.parent = &dev->dev; | 
|  | } | 
|  |  | 
|  | err = 0; | 
|  | if (info->list_size == 1) { | 
|  | info->cmtd = info->list[0].mtd; | 
|  | } else if (info->list_size > 1) { | 
|  | /* | 
|  | * We detected multiple devices. Concatenate them together. | 
|  | */ | 
|  | info->cmtd = mtd_concat_create(mtd_list, info->list_size, | 
|  | dev_name(&dev->dev)); | 
|  | if (info->cmtd == NULL) | 
|  | err = -ENXIO; | 
|  | } | 
|  | if (err) | 
|  | goto err_out; | 
|  |  | 
|  | ppdata.of_node = dp; | 
|  | part_probe_types = of_get_probes(dp); | 
|  | mtd_device_parse_register(info->cmtd, part_probe_types, &ppdata, | 
|  | NULL, 0); | 
|  | of_free_probes(part_probe_types); | 
|  |  | 
|  | kfree(mtd_list); | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | err_out: | 
|  | kfree(mtd_list); | 
|  | err_flash_remove: | 
|  | of_flash_remove(dev); | 
|  |  | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static struct of_device_id of_flash_match[] = { | 
|  | { | 
|  | .compatible	= "cfi-flash", | 
|  | .data		= (void *)"cfi_probe", | 
|  | }, | 
|  | { | 
|  | /* FIXME: JEDEC chips can't be safely and reliably | 
|  | * probed, although the mtd code gets it right in | 
|  | * practice most of the time.  We should use the | 
|  | * vendor and device ids specified by the binding to | 
|  | * bypass the heuristic probe code, but the mtd layer | 
|  | * provides, at present, no interface for doing so | 
|  | * :(. */ | 
|  | .compatible	= "jedec-flash", | 
|  | .data		= (void *)"jedec_probe", | 
|  | }, | 
|  | { | 
|  | .compatible     = "mtd-ram", | 
|  | .data           = (void *)"map_ram", | 
|  | }, | 
|  | { | 
|  | .type		= "rom", | 
|  | .compatible	= "direct-mapped" | 
|  | }, | 
|  | { }, | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(of, of_flash_match); | 
|  |  | 
|  | static struct platform_driver of_flash_driver = { | 
|  | .driver = { | 
|  | .name = "of-flash", | 
|  | .owner = THIS_MODULE, | 
|  | .of_match_table = of_flash_match, | 
|  | }, | 
|  | .probe		= of_flash_probe, | 
|  | .remove		= of_flash_remove, | 
|  | }; | 
|  |  | 
|  | static int __init of_flash_init(void) | 
|  | { | 
|  | return platform_driver_register(&of_flash_driver); | 
|  | } | 
|  |  | 
|  | static void __exit of_flash_exit(void) | 
|  | { | 
|  | platform_driver_unregister(&of_flash_driver); | 
|  | } | 
|  |  | 
|  | module_init(of_flash_init); | 
|  | module_exit(of_flash_exit); | 
|  |  | 
|  | MODULE_LICENSE("GPL"); | 
|  | MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>"); | 
|  | MODULE_DESCRIPTION("Device tree based MTD map driver"); |