path: root/include/misc/charlcd.h
diff options
authorGeert Uytterhoeven <geert@linux-m68k.org>2017-03-10 15:15:18 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-03-17 15:10:49 +0900
commitac201479cc695cb0140e425b9ca8ab2ecdcd2f0d (patch)
tree78929b3866d2bc0af026c538cd20b72de477c5da /include/misc/charlcd.h
parent39f8ea46724efbed3ca021863a22337c31be264c (diff)
auxdisplay: charlcd: Add support for 4-bit interfaces
In 4-bit mode, 8-bit commands and data are written using two raw writes to the data interface: high nibble first, low nibble last. This must be handled by the low-level driver. However, as we don't know in which mode (4-bit or 8-bit) nor 4-bit phase the LCD was left, initialization must always be handled using raw writes, and needs to configure the LCD for 8-bit mode first. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/misc/charlcd.h')
1 files changed, 2 insertions, 0 deletions
diff --git a/include/misc/charlcd.h b/include/misc/charlcd.h
index c40047b673c9..23f61850f363 100644
--- a/include/misc/charlcd.h
+++ b/include/misc/charlcd.h
@@ -14,6 +14,7 @@ struct charlcd {
const struct charlcd_ops *ops;
const unsigned char *char_conv; /* Optional */
+ int ifwidth; /* 4-bit or 8-bit (default) */
int height;
int width;
int bwidth; /* Default set by charlcd_alloc() */
@@ -28,6 +29,7 @@ struct charlcd_ops {
void (*write_data)(struct charlcd *lcd, int data);
/* Optional */
+ void (*write_cmd_raw4)(struct charlcd *lcd, int cmd); /* 4-bit only */
void (*clear_fast)(struct charlcd *lcd);
void (*backlight)(struct charlcd *lcd, int on);

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