 d281b80c46
			
		
	
	
	d281b80c46
	
	
	
		
			
			In current implementation, there is a memory leak if ab3100_otp_read fail. And in the case of ab3100_otp_init_debugfs fail, it does not properly remove sysfs entries. This patch properly handle above failure cases. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
		
			
				
	
	
		
			267 lines
		
	
	
	
		
			6.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			267 lines
		
	
	
	
		
			6.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * drivers/mfd/ab3100_otp.c
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|  *
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|  * Copyright (C) 2007-2009 ST-Ericsson AB
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|  * License terms: GNU General Public License (GPL) version 2
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|  * Driver to read out OTP from the AB3100 Mixed-signal circuit
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|  * Author: Linus Walleij <linus.walleij@stericsson.com>
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|  */
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| 
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| #include <linux/module.h>
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| #include <linux/kernel.h>
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| #include <linux/slab.h>
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| #include <linux/init.h>
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| #include <linux/platform_device.h>
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| #include <linux/mfd/abx500.h>
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| #include <linux/debugfs.h>
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| #include <linux/seq_file.h>
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| 
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| /* The OTP registers */
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| #define AB3100_OTP0		0xb0
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| #define AB3100_OTP1		0xb1
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| #define AB3100_OTP2		0xb2
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| #define AB3100_OTP3		0xb3
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| #define AB3100_OTP4		0xb4
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| #define AB3100_OTP5		0xb5
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| #define AB3100_OTP6		0xb6
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| #define AB3100_OTP7		0xb7
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| #define AB3100_OTPP		0xbf
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| 
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| /**
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|  * struct ab3100_otp
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|  * @dev containing device
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|  * @locked whether the OTP is locked, after locking, no more bits
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|  *       can be changed but before locking it is still possible
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|  *       to change bits from 1->0.
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|  * @freq clocking frequency for the OTP, this frequency is either
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|  *       32768Hz or 1MHz/30
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|  * @paf product activation flag, indicates whether this is a real
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|  *       product (paf true) or a lab board etc (paf false)
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|  * @imeich if this is set it is possible to override the
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|  *       IMEI number found in the tac, fac and svn fields with
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|  *       (secured) software
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|  * @cid customer ID
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|  * @tac type allocation code of the IMEI
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|  * @fac final assembly code of the IMEI
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|  * @svn software version number of the IMEI
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|  * @debugfs a debugfs file used when dumping to file
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|  */
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| struct ab3100_otp {
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| 	struct device *dev;
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| 	bool locked;
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| 	u32 freq;
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| 	bool paf;
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| 	bool imeich;
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| 	u16 cid:14;
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| 	u32 tac:20;
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| 	u8 fac;
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| 	u32 svn:20;
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| 	struct dentry *debugfs;
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| };
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| 
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| static int __init ab3100_otp_read(struct ab3100_otp *otp)
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| {
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| 	u8 otpval[8];
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| 	u8 otpp;
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| 	int err;
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| 
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| 	err = abx500_get_register_interruptible(otp->dev, 0,
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| 		AB3100_OTPP, &otpp);
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| 	if (err) {
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| 		dev_err(otp->dev, "unable to read OTPP register\n");
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| 		return err;
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| 	}
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| 
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| 	err = abx500_get_register_page_interruptible(otp->dev, 0,
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| 		AB3100_OTP0, otpval, 8);
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| 	if (err) {
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| 		dev_err(otp->dev, "unable to read OTP register page\n");
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| 		return err;
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| 	}
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| 
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| 	/* Cache OTP properties, they never change by nature */
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| 	otp->locked = (otpp & 0x80);
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| 	otp->freq = (otpp & 0x40) ? 32768 : 34100;
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| 	otp->paf = (otpval[1] & 0x80);
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| 	otp->imeich = (otpval[1] & 0x40);
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| 	otp->cid = ((otpval[1] << 8) | otpval[0]) & 0x3fff;
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| 	otp->tac = ((otpval[4] & 0x0f) << 16) | (otpval[3] << 8) | otpval[2];
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| 	otp->fac = ((otpval[5] & 0x0f) << 4) | (otpval[4] >> 4);
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| 	otp->svn = (otpval[7] << 12) | (otpval[6] << 4) | (otpval[5] >> 4);
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| 	return 0;
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| }
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| 
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| /*
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|  * This is a simple debugfs human-readable file that dumps out
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|  * the contents of the OTP.
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|  */
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| #ifdef CONFIG_DEBUG_FS
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| static int ab3100_show_otp(struct seq_file *s, void *v)
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| {
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| 	struct ab3100_otp *otp = s->private;
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| 
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| 	seq_printf(s, "OTP is %s\n", otp->locked ? "LOCKED" : "UNLOCKED");
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| 	seq_printf(s, "OTP clock switch startup is %uHz\n", otp->freq);
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| 	seq_printf(s, "PAF is %s\n", otp->paf ? "SET" : "NOT SET");
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| 	seq_printf(s, "IMEI is %s\n", otp->imeich ?
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| 		   "CHANGEABLE" : "NOT CHANGEABLE");
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| 	seq_printf(s, "CID: 0x%04x (decimal: %d)\n", otp->cid, otp->cid);
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| 	seq_printf(s, "IMEI: %u-%u-%u\n", otp->tac, otp->fac, otp->svn);
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| 	return 0;
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| }
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| 
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| static int ab3100_otp_open(struct inode *inode, struct file *file)
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| {
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| 	return single_open(file, ab3100_show_otp, inode->i_private);
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| }
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| 
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| static const struct file_operations ab3100_otp_operations = {
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| 	.open		= ab3100_otp_open,
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| 	.read		= seq_read,
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| 	.llseek		= seq_lseek,
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| 	.release	= single_release,
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| };
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| 
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| static int __init ab3100_otp_init_debugfs(struct device *dev,
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| 					  struct ab3100_otp *otp)
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| {
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| 	otp->debugfs = debugfs_create_file("ab3100_otp", S_IFREG | S_IRUGO,
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| 					   NULL, otp,
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| 					   &ab3100_otp_operations);
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| 	if (!otp->debugfs) {
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| 		dev_err(dev, "AB3100 debugfs OTP file registration failed!\n");
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| 		return -ENOENT;
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| 	}
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| 	return 0;
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| }
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| 
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| static void __exit ab3100_otp_exit_debugfs(struct ab3100_otp *otp)
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| {
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| 	debugfs_remove(otp->debugfs);
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| }
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| #else
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| /* Compile this out if debugfs not selected */
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| static inline int __init ab3100_otp_init_debugfs(struct device *dev,
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| 						 struct ab3100_otp *otp)
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| {
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| 	return 0;
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| }
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| 
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| static inline void __exit ab3100_otp_exit_debugfs(struct ab3100_otp *otp)
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| {
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| }
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| #endif
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| 
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| #define SHOW_AB3100_ATTR(name) \
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| static ssize_t ab3100_otp_##name##_show(struct device *dev, \
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| 			       struct device_attribute *attr, \
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| 			       char *buf) \
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| {\
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| 	struct ab3100_otp *otp = dev_get_drvdata(dev); \
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| 	return sprintf(buf, "%u\n", otp->name); \
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| }
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| 
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| SHOW_AB3100_ATTR(locked)
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| SHOW_AB3100_ATTR(freq)
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| SHOW_AB3100_ATTR(paf)
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| SHOW_AB3100_ATTR(imeich)
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| SHOW_AB3100_ATTR(cid)
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| SHOW_AB3100_ATTR(fac)
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| SHOW_AB3100_ATTR(tac)
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| SHOW_AB3100_ATTR(svn)
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| 
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| static struct device_attribute ab3100_otp_attrs[] = {
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| 	__ATTR(locked, S_IRUGO, ab3100_otp_locked_show, NULL),
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| 	__ATTR(freq, S_IRUGO, ab3100_otp_freq_show, NULL),
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| 	__ATTR(paf, S_IRUGO, ab3100_otp_paf_show, NULL),
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| 	__ATTR(imeich, S_IRUGO, ab3100_otp_imeich_show, NULL),
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| 	__ATTR(cid, S_IRUGO, ab3100_otp_cid_show, NULL),
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| 	__ATTR(fac, S_IRUGO, ab3100_otp_fac_show, NULL),
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| 	__ATTR(tac, S_IRUGO, ab3100_otp_tac_show, NULL),
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| 	__ATTR(svn, S_IRUGO, ab3100_otp_svn_show, NULL),
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| };
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| 
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| static int __init ab3100_otp_probe(struct platform_device *pdev)
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| {
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| 	struct ab3100_otp *otp;
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| 	int err = 0;
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| 	int i;
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| 
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| 	otp = kzalloc(sizeof(struct ab3100_otp), GFP_KERNEL);
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| 	if (!otp) {
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| 		dev_err(&pdev->dev, "could not allocate AB3100 OTP device\n");
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| 		return -ENOMEM;
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| 	}
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| 	otp->dev = &pdev->dev;
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| 
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| 	/* Replace platform data coming in with a local struct */
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| 	platform_set_drvdata(pdev, otp);
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| 
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| 	err = ab3100_otp_read(otp);
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| 	if (err)
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| 		goto err_otp_read;
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| 
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| 	dev_info(&pdev->dev, "AB3100 OTP readout registered\n");
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| 
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| 	/* sysfs entries */
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| 	for (i = 0; i < ARRAY_SIZE(ab3100_otp_attrs); i++) {
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| 		err = device_create_file(&pdev->dev,
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| 					 &ab3100_otp_attrs[i]);
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| 		if (err)
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| 			goto err_create_file;
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| 	}
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| 
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| 	/* debugfs entries */
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| 	err = ab3100_otp_init_debugfs(&pdev->dev, otp);
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| 	if (err)
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| 		goto err_init_debugfs;
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| 
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| 	return 0;
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| 
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| err_init_debugfs:
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| err_create_file:
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| 	while (--i >= 0)
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| 		device_remove_file(&pdev->dev, &ab3100_otp_attrs[i]);
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| err_otp_read:
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| 	kfree(otp);
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| 	return err;
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| }
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| 
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| static int __exit ab3100_otp_remove(struct platform_device *pdev)
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| {
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| 	struct ab3100_otp *otp = platform_get_drvdata(pdev);
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| 	int i;
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| 
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| 	for (i = 0; i < ARRAY_SIZE(ab3100_otp_attrs); i++)
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| 		device_remove_file(&pdev->dev,
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| 				   &ab3100_otp_attrs[i]);
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| 	ab3100_otp_exit_debugfs(otp);
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| 	kfree(otp);
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| 	return 0;
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| }
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| 
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| static struct platform_driver ab3100_otp_driver = {
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| 	.driver = {
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| 		.name = "ab3100-otp",
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| 		.owner = THIS_MODULE,
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| 	},
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| 	.remove	 = __exit_p(ab3100_otp_remove),
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| };
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| 
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| static int __init ab3100_otp_init(void)
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| {
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| 	return platform_driver_probe(&ab3100_otp_driver,
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| 				     ab3100_otp_probe);
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| }
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| 
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| static void __exit ab3100_otp_exit(void)
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| {
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| 	platform_driver_unregister(&ab3100_otp_driver);
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| }
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| 
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| module_init(ab3100_otp_init);
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| module_exit(ab3100_otp_exit);
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| 
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| MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
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| MODULE_DESCRIPTION("AB3100 OTP Readout Driver");
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| MODULE_LICENSE("GPL");
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