diff options
Diffstat (limited to 'drivers/misc/eeprom/sunxi_sid.c')
| -rw-r--r-- | drivers/misc/eeprom/sunxi_sid.c | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/drivers/misc/eeprom/sunxi_sid.c b/drivers/misc/eeprom/sunxi_sid.c deleted file mode 100644 index 8385177ff..000000000 --- a/drivers/misc/eeprom/sunxi_sid.c +++ /dev/null @@ -1,156 +0,0 @@ -/* - * Copyright (c) 2013 Oliver Schinagl <oliver@schinagl.nl> - * http://www.linux-sunxi.org - * - * 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. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver exposes the Allwinner security ID, efuses exported in byte- - * sized chunks. - */ - -#include <linux/compiler.h> -#include <linux/device.h> -#include <linux/err.h> -#include <linux/export.h> -#include <linux/fs.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/kobject.h> -#include <linux/module.h> -#include <linux/of_device.h> -#include <linux/platform_device.h> -#include <linux/random.h> -#include <linux/slab.h> -#include <linux/stat.h> -#include <linux/sysfs.h> -#include <linux/types.h> - -#define DRV_NAME "sunxi-sid" - -struct sunxi_sid_data { - void __iomem *reg_base; - unsigned int keysize; -}; - -/* We read the entire key, due to a 32 bit read alignment requirement. Since we - * want to return the requested byte, this results in somewhat slower code and - * uses 4 times more reads as needed but keeps code simpler. Since the SID is - * only very rarely probed, this is not really an issue. - */ -static u8 sunxi_sid_read_byte(const struct sunxi_sid_data *sid_data, - const unsigned int offset) -{ - u32 sid_key; - - if (offset >= sid_data->keysize) - return 0; - - sid_key = ioread32be(sid_data->reg_base + round_down(offset, 4)); - sid_key >>= (offset % 4) * 8; - - return sid_key; /* Only return the last byte */ -} - -static ssize_t sid_read(struct file *fd, struct kobject *kobj, - struct bin_attribute *attr, char *buf, - loff_t pos, size_t size) -{ - struct platform_device *pdev; - struct sunxi_sid_data *sid_data; - int i; - - pdev = to_platform_device(kobj_to_dev(kobj)); - sid_data = platform_get_drvdata(pdev); - - if (pos < 0 || pos >= sid_data->keysize) - return 0; - if (size > sid_data->keysize - pos) - size = sid_data->keysize - pos; - - for (i = 0; i < size; i++) - buf[i] = sunxi_sid_read_byte(sid_data, pos + i); - - return i; -} - -static struct bin_attribute sid_bin_attr = { - .attr = { .name = "eeprom", .mode = S_IRUGO, }, - .read = sid_read, -}; - -static int sunxi_sid_remove(struct platform_device *pdev) -{ - device_remove_bin_file(&pdev->dev, &sid_bin_attr); - dev_dbg(&pdev->dev, "driver unloaded\n"); - - return 0; -} - -static const struct of_device_id sunxi_sid_of_match[] = { - { .compatible = "allwinner,sun4i-a10-sid", .data = (void *)16}, - { .compatible = "allwinner,sun7i-a20-sid", .data = (void *)512}, - {/* sentinel */}, -}; -MODULE_DEVICE_TABLE(of, sunxi_sid_of_match); - -static int sunxi_sid_probe(struct platform_device *pdev) -{ - struct sunxi_sid_data *sid_data; - struct resource *res; - const struct of_device_id *of_dev_id; - u8 *entropy; - unsigned int i; - - sid_data = devm_kzalloc(&pdev->dev, sizeof(struct sunxi_sid_data), - GFP_KERNEL); - if (!sid_data) - return -ENOMEM; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - sid_data->reg_base = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(sid_data->reg_base)) - return PTR_ERR(sid_data->reg_base); - - of_dev_id = of_match_device(sunxi_sid_of_match, &pdev->dev); - if (!of_dev_id) - return -ENODEV; - sid_data->keysize = (int)of_dev_id->data; - - platform_set_drvdata(pdev, sid_data); - - sid_bin_attr.size = sid_data->keysize; - if (device_create_bin_file(&pdev->dev, &sid_bin_attr)) - return -ENODEV; - - entropy = kzalloc(sizeof(u8) * sid_data->keysize, GFP_KERNEL); - for (i = 0; i < sid_data->keysize; i++) - entropy[i] = sunxi_sid_read_byte(sid_data, i); - add_device_randomness(entropy, sid_data->keysize); - kfree(entropy); - - dev_dbg(&pdev->dev, "loaded\n"); - - return 0; -} - -static struct platform_driver sunxi_sid_driver = { - .probe = sunxi_sid_probe, - .remove = sunxi_sid_remove, - .driver = { - .name = DRV_NAME, - .of_match_table = sunxi_sid_of_match, - }, -}; -module_platform_driver(sunxi_sid_driver); - -MODULE_AUTHOR("Oliver Schinagl <oliver@schinagl.nl>"); -MODULE_DESCRIPTION("Allwinner sunxi security id driver"); -MODULE_LICENSE("GPL"); |