mtd: nand: gpio: improve comments about GPIO assisted operation

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=c9d79c4bbb0e47a75f35652567b2647b99d6295e
Commit:     c9d79c4bbb0e47a75f35652567b2647b99d6295e
Parent:     f861a9253e7f456d870f8dd46bdde2ac02149bc6
Author:     Gerhard Sittig <gsi at denx.de>
AuthorDate: Tue Aug 5 10:37:26 2014 +0200
Committer:  Brian Norris <computersforpeace at gmail.com>
CommitDate: Tue Nov 4 23:53:07 2014 -0800

    mtd: nand: gpio: improve comments about GPIO assisted operation
    
    The drivers/mtd/nand/gpio.c driver does not GPIO bitbang the complete
    NAND protocol, but instead is GPIO _assisted_ -- a memory mapped interface
    communicates commands and data, and only few control signals are connected
    to GPIO pins.
    
    Expand comments in the driver source and in the Kconfig description to
    better reflect the very nature of the driver.  The previous text could be
    mistaken for complete GPIO bitbanging.
    
    Signed-off-by: Gerhard Sittig <gsi at denx.de>
    Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
 drivers/mtd/nand/Kconfig | 6 ++++--
 drivers/mtd/nand/gpio.c  | 4 +++-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 4c51d2c..7d0150d 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -75,10 +75,12 @@ config MTD_NAND_DENALI_SCRATCH_REG_ADDR
           boards, the scratch register is at 0xFF108018.
 
 config MTD_NAND_GPIO
-	tristate "GPIO NAND Flash driver"
+	tristate "GPIO assisted NAND Flash driver"
 	depends on GPIOLIB
 	help
-	  This enables a GPIO based NAND flash driver.
+	  This enables a NAND flash driver where control signals are
+	  connected to GPIO pins, and commands and data are communicated
+	  via a memory mapped interface.
 
 config MTD_NAND_AMS_DELTA
 	tristate "NAND Flash device on Amstrad E3"
diff --git a/drivers/mtd/nand/gpio.c b/drivers/mtd/nand/gpio.c
index 117ce33..226eda6 100644
--- a/drivers/mtd/nand/gpio.c
+++ b/drivers/mtd/nand/gpio.c
@@ -8,7 +8,9 @@
  *
  * © 2004 Simtec Electronics
  *
- * Device driver for NAND connected via GPIO
+ * Device driver for NAND flash that uses a memory mapped interface to
+ * read/write the NAND commands and data, and GPIO pins for control signals
+ * (the DT binding refers to this as "GPIO assisted NAND flash")
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as