diff options
Diffstat (limited to 'drivers/char/bfin-otp.c')
-rw-r--r-- | drivers/char/bfin-otp.c | 237 |
1 files changed, 0 insertions, 237 deletions
diff --git a/drivers/char/bfin-otp.c b/drivers/char/bfin-otp.c deleted file mode 100644 index 0584025bb0c2..000000000000 --- a/drivers/char/bfin-otp.c +++ /dev/null @@ -1,237 +0,0 @@ -/* - * Blackfin On-Chip OTP Memory Interface - * - * Copyright 2007-2009 Analog Devices Inc. - * - * Enter bugs at http://blackfin.uclinux.org/ - * - * Licensed under the GPL-2 or later. - */ - -#include <linux/device.h> -#include <linux/errno.h> -#include <linux/fs.h> -#include <linux/init.h> -#include <linux/miscdevice.h> -#include <linux/module.h> -#include <linux/mutex.h> -#include <linux/types.h> -#include <mtd/mtd-abi.h> - -#include <asm/blackfin.h> -#include <asm/bfrom.h> -#include <linux/uaccess.h> - -#define stamp(fmt, args...) pr_debug("%s:%i: " fmt "\n", __func__, __LINE__, ## args) -#define stampit() stamp("here i am") -#define pr_init(fmt, args...) ({ static const __initconst char __fmt[] = fmt; printk(__fmt, ## args); }) - -#define DRIVER_NAME "bfin-otp" -#define PFX DRIVER_NAME ": " - -static DEFINE_MUTEX(bfin_otp_lock); - -/** - * bfin_otp_read - Read OTP pages - * - * All reads must be in half page chunks (half page == 64 bits). - */ -static ssize_t bfin_otp_read(struct file *file, char __user *buff, size_t count, loff_t *pos) -{ - ssize_t bytes_done; - u32 page, flags, ret; - u64 content; - - stampit(); - - if (count % sizeof(u64)) - return -EMSGSIZE; - - if (mutex_lock_interruptible(&bfin_otp_lock)) - return -ERESTARTSYS; - - bytes_done = 0; - page = *pos / (sizeof(u64) * 2); - while (bytes_done < count) { - flags = (*pos % (sizeof(u64) * 2) ? OTP_UPPER_HALF : OTP_LOWER_HALF); - stamp("processing page %i (0x%x:%s)", page, flags, - (flags & OTP_UPPER_HALF ? "upper" : "lower")); - ret = bfrom_OtpRead(page, flags, &content); - if (ret & OTP_MASTER_ERROR) { - stamp("error from otp: 0x%x", ret); - bytes_done = -EIO; - break; - } - if (copy_to_user(buff + bytes_done, &content, sizeof(content))) { - bytes_done = -EFAULT; - break; - } - if (flags & OTP_UPPER_HALF) - ++page; - bytes_done += sizeof(content); - *pos += sizeof(content); - } - - mutex_unlock(&bfin_otp_lock); - - return bytes_done; -} - -#ifdef CONFIG_BFIN_OTP_WRITE_ENABLE -static bool allow_writes; - -/** - * bfin_otp_init_timing - setup OTP timing parameters - * - * Required before doing any write operation. Algorithms from HRM. - */ -static u32 bfin_otp_init_timing(void) -{ - u32 tp1, tp2, tp3, timing; - - tp1 = get_sclk() / 1000000; - tp2 = (2 * get_sclk() / 10000000) << 8; - tp3 = (0x1401) << 15; - timing = tp1 | tp2 | tp3; - if (bfrom_OtpCommand(OTP_INIT, timing)) - return 0; - - return timing; -} - -/** - * bfin_otp_deinit_timing - set timings to only allow reads - * - * Should be called after all writes are done. - */ -static void bfin_otp_deinit_timing(u32 timing) -{ - /* mask bits [31:15] so that any attempts to write fail */ - bfrom_OtpCommand(OTP_CLOSE, 0); - bfrom_OtpCommand(OTP_INIT, timing & ~(-1 << 15)); - bfrom_OtpCommand(OTP_CLOSE, 0); -} - -/** - * bfin_otp_write - write OTP pages - * - * All writes must be in half page chunks (half page == 64 bits). - */ -static ssize_t bfin_otp_write(struct file *filp, const char __user *buff, size_t count, loff_t *pos) -{ - ssize_t bytes_done; - u32 timing, page, base_flags, flags, ret; - u64 content; - - if (!allow_writes) - return -EACCES; - - if (count % sizeof(u64)) - return -EMSGSIZE; - - if (mutex_lock_interruptible(&bfin_otp_lock)) - return -ERESTARTSYS; - - stampit(); - - timing = bfin_otp_init_timing(); - if (timing == 0) { - mutex_unlock(&bfin_otp_lock); - return -EIO; - } - - base_flags = OTP_CHECK_FOR_PREV_WRITE; - - bytes_done = 0; - page = *pos / (sizeof(u64) * 2); - while (bytes_done < count) { - flags = base_flags | (*pos % (sizeof(u64) * 2) ? OTP_UPPER_HALF : OTP_LOWER_HALF); - stamp("processing page %i (0x%x:%s) from %p", page, flags, - (flags & OTP_UPPER_HALF ? "upper" : "lower"), buff + bytes_done); - if (copy_from_user(&content, buff + bytes_done, sizeof(content))) { - bytes_done = -EFAULT; - break; - } - ret = bfrom_OtpWrite(page, flags, &content); - if (ret & OTP_MASTER_ERROR) { - stamp("error from otp: 0x%x", ret); - bytes_done = -EIO; - break; - } - if (flags & OTP_UPPER_HALF) - ++page; - bytes_done += sizeof(content); - *pos += sizeof(content); - } - - bfin_otp_deinit_timing(timing); - - mutex_unlock(&bfin_otp_lock); - - return bytes_done; -} - -static long bfin_otp_ioctl(struct file *filp, unsigned cmd, unsigned long arg) -{ - stampit(); - - switch (cmd) { - case OTPLOCK: { - u32 timing; - int ret = -EIO; - - if (!allow_writes) - return -EACCES; - - if (mutex_lock_interruptible(&bfin_otp_lock)) - return -ERESTARTSYS; - - timing = bfin_otp_init_timing(); - if (timing) { - u32 otp_result = bfrom_OtpWrite(arg, OTP_LOCK, NULL); - stamp("locking page %lu resulted in 0x%x", arg, otp_result); - if (!(otp_result & OTP_MASTER_ERROR)) - ret = 0; - - bfin_otp_deinit_timing(timing); - } - - mutex_unlock(&bfin_otp_lock); - - return ret; - } - - case MEMLOCK: - allow_writes = false; - return 0; - - case MEMUNLOCK: - allow_writes = true; - return 0; - } - - return -EINVAL; -} -#else -# define bfin_otp_write NULL -# define bfin_otp_ioctl NULL -#endif - -static const struct file_operations bfin_otp_fops = { - .owner = THIS_MODULE, - .unlocked_ioctl = bfin_otp_ioctl, - .read = bfin_otp_read, - .write = bfin_otp_write, - .llseek = default_llseek, -}; - -static struct miscdevice bfin_otp_misc_device = { - .minor = MISC_DYNAMIC_MINOR, - .name = DRIVER_NAME, - .fops = &bfin_otp_fops, -}; -module_misc_device(bfin_otp_misc_device); - -MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>"); -MODULE_DESCRIPTION("Blackfin OTP Memory Interface"); -MODULE_LICENSE("GPL"); |