openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

eeprom: ee1004: Deal with nack on page selection 

Some EE1004 implementations will not properly ack page selection
commands. They still set the page correctly, so there is no actual
error. Deal with this case gracefully by checking the currently
selected page after we receive a nack. If the page is set right then
we can continue.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jean Delvare 2019-05-06 15:16:56 +02:00 committed by Greg Kroah-Hartman
parent 5d45875174
commit 31641e34e8
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/misc/eeprom/ee1004.c
View File

@ -1,7 +1,7 @@
/*
* ee1004 - driver for DDR4 SPD EEPROMs
*
* Copyright (C) 2017 Jean Delvare
* Copyright (C) 2017-2019 Jean Delvare
*
* Based on the at24 driver:
* Copyright (C) 2005-2007 David Brownell
@ -124,6 +124,16 @@ static ssize_t ee1004_read(struct file *filp, struct kobject *kobj,
/* Data is ignored */
status = i2c_smbus_write_byte(ee1004_set_page[page],
0x00);
if (status == -ENXIO) {
/*
* Don't give up just yet. Some memory
* modules will select the page but not
* ack the command. Check which page is
* selected now.
*/
if (ee1004_get_current_page() == page)
status = 0;
}
if (status < 0) {
dev_err(dev, "Failed to select page %d (%d)\n",
page, status);