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[PATCH v5 1/5] misc: eeprom_93xx46: Fix 16-bit read and write accesses.

From Cory Tusar <cory.tusar@pid1solutions.com>
Newsgroups linux.kernel
Subject [PATCH v5 1/5] misc: eeprom_93xx46: Fix 16-bit read and write accesses.
Date 2016-01-07 05:00 +0100
Message-ID <qO9TY-2mQ-13@gated-at.bofh.it> (permalink)
References <qO9TX-2mQ-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

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Compatible at93xx46 devices from both Microchip and Atmel expect a
word-based address, regardless of whether the device is strapped for 8-
or 16-bit operation.  However, the offset parameter passed in when
reading or writing at a specific location is always specified in terms
of bytes.

This commit fixes 16-bit read and write accesses by shifting the offset
parameter to account for this difference between a byte offset and a
word-based address.

Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Tested-by: Chris Healy <chris.healy@zii.aero>
---
 drivers/misc/eeprom/eeprom_93xx46.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index ff63f05..e1bf0a5 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c
@@ -54,7 +54,7 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
 		cmd_addr |= off & 0x7f;
 		bits = 10;
 	} else {
-		cmd_addr |= off & 0x3f;
+		cmd_addr |= (off >> 1) & 0x3f;
 		bits = 9;
 	}
 
@@ -155,7 +155,7 @@ eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev,
 		bits = 10;
 		data_len = 1;
 	} else {
-		cmd_addr |= off & 0x3f;
+		cmd_addr |= (off >> 1) & 0x3f;
 		bits = 9;
 		data_len = 2;
 	}
-- 
2.4.10

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[PATCH v5 1/5] misc: eeprom_93xx46: Fix 16-bit read and write accesses. Cory Tusar <cory.tusar@pid1solutions.com> - 2016-01-07 05:00 +0100

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