[PATCH v4 1/5] misc: eeprom_93xx46: Fix 16-bit read and write accesses.

From: Cory Tusar
Date: Wed Dec 09 2015 - 23:01:21 EST


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@xxxxxxxxxxxxxxxxx>
Tested-by: Chris Healy <chris.healy@xxxxxxxx>
---
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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