Subject: [patch 1/9] eeprom_93cx6: Add data direction control.

From: [email-masked]
Date: Mon, 07 Dec 2009 12:15:02 +0000

Some devices need to know if the data is to be output or read, so add a
data direction into the eeprom structure to tell the driver whether the
data line should be driven.

The user in this case is the Micrel KS8851 which has a direction
control for the EEPROM data line and thus needs to know whether
to drive it (writing) or to tristate it for receiving.

Signed-off-by: Ben Dooks <[email-masked]>
Cc: Wolfram Sang <[email-masked]>
Cc: Jean Delvare <[email-masked]>
Cc: Linux Kernel <[email-masked]>

--
 drivers/misc/eeprom/eeprom_93cx6.c |    3 +++
 include/linux/eeprom_93cx6.h       |    2 ++
 2 files changed, 5 insertions(+)

Index: b/drivers/misc/eeprom/eeprom_93cx6.c
===================================================================
--- a/drivers/misc/eeprom/eeprom_93cx6.c	2009-10-06 15:35:38.000000000 +0100
+++ b/drivers/misc/eeprom/eeprom_93cx6.c	2009-10-06 15:51:18.000000000 +0100
@@ -70,6 +70,7 @@ static void eeprom_93cx6_startup(struct 
 	eeprom->reg_data_out = 0;
 	eeprom->reg_data_clock = 0;
 	eeprom->reg_chip_select = 1;
+	eeprom->drive_data = 1;
 	eeprom->register_write(eeprom);
 
 	/*
@@ -108,6 +109,7 @@ static void eeprom_93cx6_write_bits(stru
 	 */
 	eeprom->reg_data_in = 0;
 	eeprom->reg_data_out = 0;
+	eeprom->drive_data = 1;
 
 	/*
 	 * Start writing all bits.
@@ -147,6 +149,7 @@ static void eeprom_93cx6_read_bits(struc
 	 */
 	eeprom->reg_data_in = 0;
 	eeprom->reg_data_out = 0;
+	eeprom->drive_data = 0;
 
 	/*
 	 * Start reading all bits.
Index: b/include/linux/eeprom_93cx6.h
===================================================================
--- a/include/linux/eeprom_93cx6.h	2009-10-06 15:35:38.000000000 +0100
+++ b/include/linux/eeprom_93cx6.h	2009-10-06 15:51:18.000000000 +0100
@@ -45,6 +45,7 @@
  * @register_write(struct eeprom_93cx6 *eeprom): handler to
  * write to the eeprom register by using all reg_* fields.
  * @width: eeprom width, should be one of the PCI_EEPROM_WIDTH_* defines
+ * @drive_data: Set if we're driving the data line.
  * @reg_data_in: register field to indicate data input
  * @reg_data_out: register field to indicate data output
  * @reg_data_clock: register field to set the data clock
@@ -61,6 +62,7 @@ struct eeprom_93cx6 {
 
 	int width;
 
+	char drive_data;
 	char reg_data_in;
 	char reg_data_out;
 	char reg_data_clock;