* [PATCH v2 0/5] Add HD44780 Character LCD support
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
Hi all,
Character LCDs are currently typically driven from userspace, either
directly through bit-banging, or via some kind of serial (UART/i2c)
interface.
This patch series adds kernel support for character LCDs using an
Hitachi HD44780 Character LCD Controller where its M6800 bus interface
is connected to GPIOs. It does so after extracting the character LCD
core support from the existing Parallel port LCD/Keypad Panel driver
into its own subdriver.
- Patch 1 extracts the character LCD core support from the panel
driver into an auxdisplay charlcd subdriver,
- Patches 2 and 3 add new features to the character LCD core driver
(support for 4-bit interfaces and displays with more than 2 lines),
- Patch 4 adds DT bindings for describing HD44780 Character LCDs,
- Patch 5 adds a driver for HD44780 Character LCDs connected to GPIOs,
using the new character LCD core.
Note that Linux has other support for HD44780 Character LCDs, but none of
it is generic:
- drivers/misc/arm-charlcd.c involves a custom IP block for interfacing
to the LCD controller,
- drivers/parisc/led.c is tightly coupled to LED handling on various HP
PA-RISC machines.
This has been tested using a 20x4 character LCD with backlight, using both
8-bit and 4-bit wiring to one or two 74HC595 shift registers connected to
an SPI master controller.
Regression testing on original "panel" hardware would be appreciated.
Changes compared to v1:
- Dropped accepted patches (panel driver fixes, cleanups, and
improvements),
- Move backlight mutex initialization before call to
charlcd_init_display(), to prevent locking an uninitialized mutex
(reported by 0day).
- Added rationale for not yet supporting memory-mapped configurations,
- Drop the dependency on OF by switching to the device property API,
- Depend on GPIOLIB || COMPILE_TEST.
Thanks!
Geert Uytterhoeven (5):
auxdisplay: charlcd: Extract character LCD core from misc/panel
auxdisplay: charlcd: Add support for 4-bit interfaces
auxdisplay: charlcd: Add support for displays with more than two lines
dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
auxdisplay: Add HD44780 Character LCD support
.../devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 ++
drivers/auxdisplay/Kconfig | 14 +
drivers/auxdisplay/Makefile | 2 +
drivers/auxdisplay/charlcd.c | 818 ++++++++++++++++++++
drivers/auxdisplay/hd44780.c | 325 ++++++++
drivers/misc/Kconfig | 1 +
drivers/misc/panel.c | 827 +++------------------
include/misc/charlcd.h | 42 ++
8 files changed, 1338 insertions(+), 735 deletions(-)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
create mode 100644 drivers/auxdisplay/charlcd.c
create mode 100644 drivers/auxdisplay/hd44780.c
create mode 100644 include/misc/charlcd.h
--
2.7.4
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v2 0/5] Add HD44780 Character LCD support
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Geert Uytterhoeven
Hi all,
Character LCDs are currently typically driven from userspace, either
directly through bit-banging, or via some kind of serial (UART/i2c)
interface.
This patch series adds kernel support for character LCDs using an
Hitachi HD44780 Character LCD Controller where its M6800 bus interface
is connected to GPIOs. It does so after extracting the character LCD
core support from the existing Parallel port LCD/Keypad Panel driver
into its own subdriver.
- Patch 1 extracts the character LCD core support from the panel
driver into an auxdisplay charlcd subdriver,
- Patches 2 and 3 add new features to the character LCD core driver
(support for 4-bit interfaces and displays with more than 2 lines),
- Patch 4 adds DT bindings for describing HD44780 Character LCDs,
- Patch 5 adds a driver for HD44780 Character LCDs connected to GPIOs,
using the new character LCD core.
Note that Linux has other support for HD44780 Character LCDs, but none of
it is generic:
- drivers/misc/arm-charlcd.c involves a custom IP block for interfacing
to the LCD controller,
- drivers/parisc/led.c is tightly coupled to LED handling on various HP
PA-RISC machines.
This has been tested using a 20x4 character LCD with backlight, using both
8-bit and 4-bit wiring to one or two 74HC595 shift registers connected to
an SPI master controller.
Regression testing on original "panel" hardware would be appreciated.
Changes compared to v1:
- Dropped accepted patches (panel driver fixes, cleanups, and
improvements),
- Move backlight mutex initialization before call to
charlcd_init_display(), to prevent locking an uninitialized mutex
(reported by 0day).
- Added rationale for not yet supporting memory-mapped configurations,
- Drop the dependency on OF by switching to the device property API,
- Depend on GPIOLIB || COMPILE_TEST.
Thanks!
Geert Uytterhoeven (5):
auxdisplay: charlcd: Extract character LCD core from misc/panel
auxdisplay: charlcd: Add support for 4-bit interfaces
auxdisplay: charlcd: Add support for displays with more than two lines
dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
auxdisplay: Add HD44780 Character LCD support
.../devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 ++
drivers/auxdisplay/Kconfig | 14 +
drivers/auxdisplay/Makefile | 2 +
drivers/auxdisplay/charlcd.c | 818 ++++++++++++++++++++
drivers/auxdisplay/hd44780.c | 325 ++++++++
drivers/misc/Kconfig | 1 +
drivers/misc/panel.c | 827 +++------------------
include/misc/charlcd.h | 42 ++
8 files changed, 1338 insertions(+), 735 deletions(-)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
create mode 100644 drivers/auxdisplay/charlcd.c
create mode 100644 drivers/auxdisplay/hd44780.c
create mode 100644 include/misc/charlcd.h
--
2.7.4
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v2 1/5] auxdisplay: charlcd: Extract character LCD core from misc/panel
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
Extract the character LCD core from the Parallel port LCD/Keypad Panel
driver in the misc subsystem, and convert it into a subdriver in the
auxdisplay subsystem. This allows the character LCD core to be used by
other drivers later.
Compilation is controlled by its own Kconfig symbol CHARLCD, which is to
be selected by its users, but can be enabled manually for
compile-testing.
All functions changed their prefix from "lcd_" to "charlcd_", and gained
a "struct charlcd *" parameter to operate on a specific instance.
While the driver API thus is ready to support multiple instances, the
current limitation of a single display (/dev/lcd has a single misc minor
assigned) is retained.
No functional changes intended.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
v2:
- Move backlight mutex initialization before call to
charlcd_init_display(), to prevent locking an uninitialized mutex
(reported by 0day).
---
drivers/auxdisplay/Kconfig | 3 +
drivers/auxdisplay/Makefile | 1 +
drivers/auxdisplay/charlcd.c | 790 +++++++++++++++++++++++++++++++++++++++++
drivers/misc/Kconfig | 1 +
drivers/misc/panel.c | 827 +++++--------------------------------------
include/misc/charlcd.h | 40 +++
6 files changed, 927 insertions(+), 735 deletions(-)
create mode 100644 drivers/auxdisplay/charlcd.c
create mode 100644 include/misc/charlcd.h
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
index 8a8e403644d6e0d6..b4686380d4e3cca9 100644
--- a/drivers/auxdisplay/Kconfig
+++ b/drivers/auxdisplay/Kconfig
@@ -13,6 +13,9 @@ menuconfig AUXDISPLAY
If you say N, all options in this submenu will be skipped and disabled.
+config CHARLCD
+ tristate "Character LCD core support" if COMPILE_TEST
+
if AUXDISPLAY
config KS0108
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
index cb3dd847713bb6d1..f56f45dcc78e332e 100644
--- a/drivers/auxdisplay/Makefile
+++ b/drivers/auxdisplay/Makefile
@@ -2,6 +2,7 @@
# Makefile for the kernel auxiliary displays device drivers.
#
+obj-$(CONFIG_CHARLCD) += charlcd.o
obj-$(CONFIG_KS0108) += ks0108.o
obj-$(CONFIG_CFAG12864B) += cfag12864b.o cfag12864bfb.o
obj-$(CONFIG_IMG_ASCII_LCD) += img-ascii-lcd.o
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
new file mode 100644
index 0000000000000000..930ffb2fb31787c5
--- /dev/null
+++ b/drivers/auxdisplay/charlcd.c
@@ -0,0 +1,790 @@
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/atomic.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+
+#include <generated/utsrelease.h>
+
+#include <misc/charlcd.h>
+
+#define LCD_MINOR 156
+
+#define DEFAULT_LCD_BWIDTH 40
+#define DEFAULT_LCD_HWIDTH 64
+
+/* Keep the backlight on this many seconds for each flash */
+#define LCD_BL_TEMPO_PERIOD 4
+
+#define LCD_FLAG_B 0x0004 /* Blink on */
+#define LCD_FLAG_C 0x0008 /* Cursor on */
+#define LCD_FLAG_D 0x0010 /* Display on */
+#define LCD_FLAG_F 0x0020 /* Large font mode */
+#define LCD_FLAG_N 0x0040 /* 2-rows mode */
+#define LCD_FLAG_L 0x0080 /* Backlight enabled */
+
+/* LCD commands */
+#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
+
+#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
+#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
+
+#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
+#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
+#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
+#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
+
+#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
+#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
+#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
+
+#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
+#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
+#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
+#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
+
+#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
+
+#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
+
+#define LCD_ESCAPE_LEN 24 /* Max chars for LCD escape command */
+#define LCD_ESCAPE_CHAR 27 /* Use char 27 for escape command */
+
+struct charlcd_priv {
+ struct charlcd lcd;
+
+ struct delayed_work bl_work;
+ struct mutex bl_tempo_lock; /* Protects access to bl_tempo */
+ bool bl_tempo;
+
+ bool must_clear;
+
+ /* contains the LCD config state */
+ unsigned long int flags;
+
+ /* Contains the LCD X and Y offset */
+ struct {
+ unsigned long int x;
+ unsigned long int y;
+ } addr;
+
+ /* Current escape sequence and it's length or -1 if outside */
+ struct {
+ char buf[LCD_ESCAPE_LEN + 1];
+ int len;
+ } esc_seq;
+
+ unsigned long long drvdata[0];
+};
+
+#define to_priv(p) container_of(p, struct charlcd_priv, lcd)
+
+/* Device single-open policy control */
+static atomic_t charlcd_available = ATOMIC_INIT(1);
+
+/* sleeps that many milliseconds with a reschedule */
+static void long_sleep(int ms)
+{
+ if (in_interrupt())
+ mdelay(ms);
+ else
+ schedule_timeout_interruptible(msecs_to_jiffies(ms));
+}
+
+/* turn the backlight on or off */
+static void charlcd_backlight(struct charlcd *lcd, int on)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (!lcd->ops->backlight)
+ return;
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (!priv->bl_tempo)
+ lcd->ops->backlight(lcd, on);
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+
+static void charlcd_bl_off(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct charlcd_priv *priv =
+ container_of(dwork, struct charlcd_priv, bl_work);
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (priv->bl_tempo) {
+ priv->bl_tempo = false;
+ if (!(priv->flags & LCD_FLAG_L))
+ priv->lcd.ops->backlight(&priv->lcd, 0);
+ }
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+
+/* turn the backlight on for a little while */
+void charlcd_poke(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (!lcd->ops->backlight)
+ return;
+
+ cancel_delayed_work_sync(&priv->bl_work);
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L))
+ lcd->ops->backlight(lcd, 1);
+ priv->bl_tempo = true;
+ schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ);
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+EXPORT_SYMBOL_GPL(charlcd_poke);
+
+static void charlcd_gotoxy(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SET_DDRAM_ADDR | (priv->addr.y ? lcd->hwidth : 0) |
+ /*
+ * we force the cursor to stay at the end of the
+ * line if it wants to go farther
+ */
+ ((priv->addr.x < lcd->bwidth) ? priv->addr.x & (lcd->hwidth - 1)
+ : lcd->bwidth - 1));
+}
+
+static void charlcd_home(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ priv->addr.x = 0;
+ priv->addr.y = 0;
+ charlcd_gotoxy(lcd);
+}
+
+static void charlcd_print(struct charlcd *lcd, char c)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (priv->addr.x < lcd->bwidth) {
+ if (lcd->char_conv)
+ c = lcd->char_conv[(unsigned char)c];
+ lcd->ops->write_data(lcd, c);
+ priv->addr.x++;
+ }
+ /* prevents the cursor from wrapping onto the next line */
+ if (priv->addr.x == lcd->bwidth)
+ charlcd_gotoxy(lcd);
+}
+
+static void charlcd_clear_fast(struct charlcd *lcd)
+{
+ int pos;
+
+ charlcd_home(lcd);
+
+ if (lcd->ops->clear_fast)
+ lcd->ops->clear_fast(lcd);
+ else
+ for (pos = 0; pos < lcd->height * lcd->hwidth; pos++)
+ lcd->ops->write_data(lcd, ' ');
+
+ charlcd_home(lcd);
+}
+
+/* clears the display and resets X/Y */
+static void charlcd_clear_display(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ lcd->ops->write_cmd(lcd, LCD_CMD_DISPLAY_CLEAR);
+ priv->addr.x = 0;
+ priv->addr.y = 0;
+ /* we must wait a few milliseconds (15) */
+ long_sleep(15);
+}
+
+static int charlcd_init_display(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+ LCD_FLAG_C | LCD_FLAG_B;
+
+ long_sleep(20); /* wait 20 ms after power-up for the paranoid */
+
+ /* 8bits, 1 line, small fonts; let's do it 3 times */
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+
+ /* set font height and lines number */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ ((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
+ long_sleep(10);
+
+ /* display off, cursor off, blink off */
+ lcd->ops->write_cmd(lcd, LCD_CMD_DISPLAY_CTRL);
+ long_sleep(10);
+
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_DISPLAY_CTRL | /* set display mode */
+ ((priv->flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0) |
+ ((priv->flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0) |
+ ((priv->flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0));
+
+ charlcd_backlight(lcd, (priv->flags & LCD_FLAG_L) ? 1 : 0);
+
+ long_sleep(10);
+
+ /* entry mode set : increment, cursor shifting */
+ lcd->ops->write_cmd(lcd, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+
+ charlcd_clear_display(lcd);
+ return 0;
+}
+
+/*
+ * These are the file operation function for user access to /dev/lcd
+ * This function can also be called from inside the kernel, by
+ * setting file and ppos to NULL.
+ *
+ */
+
+static inline int handle_lcd_special_code(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ /* LCD special codes */
+
+ int processed = 0;
+
+ char *esc = priv->esc_seq.buf + 2;
+ int oldflags = priv->flags;
+
+ /* check for display mode flags */
+ switch (*esc) {
+ case 'D': /* Display ON */
+ priv->flags |= LCD_FLAG_D;
+ processed = 1;
+ break;
+ case 'd': /* Display OFF */
+ priv->flags &= ~LCD_FLAG_D;
+ processed = 1;
+ break;
+ case 'C': /* Cursor ON */
+ priv->flags |= LCD_FLAG_C;
+ processed = 1;
+ break;
+ case 'c': /* Cursor OFF */
+ priv->flags &= ~LCD_FLAG_C;
+ processed = 1;
+ break;
+ case 'B': /* Blink ON */
+ priv->flags |= LCD_FLAG_B;
+ processed = 1;
+ break;
+ case 'b': /* Blink OFF */
+ priv->flags &= ~LCD_FLAG_B;
+ processed = 1;
+ break;
+ case '+': /* Back light ON */
+ priv->flags |= LCD_FLAG_L;
+ processed = 1;
+ break;
+ case '-': /* Back light OFF */
+ priv->flags &= ~LCD_FLAG_L;
+ processed = 1;
+ break;
+ case '*': /* Flash back light */
+ charlcd_poke(lcd);
+ processed = 1;
+ break;
+ case 'f': /* Small Font */
+ priv->flags &= ~LCD_FLAG_F;
+ processed = 1;
+ break;
+ case 'F': /* Large Font */
+ priv->flags |= LCD_FLAG_F;
+ processed = 1;
+ break;
+ case 'n': /* One Line */
+ priv->flags &= ~LCD_FLAG_N;
+ processed = 1;
+ break;
+ case 'N': /* Two Lines */
+ priv->flags |= LCD_FLAG_N;
+ break;
+ case 'l': /* Shift Cursor Left */
+ if (priv->addr.x > 0) {
+ /* back one char if not at end of line */
+ if (priv->addr.x < lcd->bwidth)
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ priv->addr.x--;
+ }
+ processed = 1;
+ break;
+ case 'r': /* shift cursor right */
+ if (priv->addr.x < lcd->width) {
+ /* allow the cursor to pass the end of the line */
+ if (priv->addr.x < (lcd->bwidth - 1))
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
+ priv->addr.x++;
+ }
+ processed = 1;
+ break;
+ case 'L': /* shift display left */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+ processed = 1;
+ break;
+ case 'R': /* shift display right */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
+ LCD_CMD_SHIFT_RIGHT);
+ processed = 1;
+ break;
+ case 'k': { /* kill end of line */
+ int x;
+
+ for (x = priv->addr.x; x < lcd->bwidth; x++)
+ lcd->ops->write_data(lcd, ' ');
+
+ /* restore cursor position */
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+ case 'I': /* reinitialize display */
+ charlcd_init_display(lcd);
+ processed = 1;
+ break;
+ case 'G': {
+ /* Generator : LGcxxxxx...xx; must have <c> between '0'
+ * and '7', representing the numerical ASCII code of the
+ * redefined character, and <xx...xx> a sequence of 16
+ * hex digits representing 8 bytes for each character.
+ * Most LCDs will only use 5 lower bits of the 7 first
+ * bytes.
+ */
+
+ unsigned char cgbytes[8];
+ unsigned char cgaddr;
+ int cgoffset;
+ int shift;
+ char value;
+ int addr;
+
+ if (!strchr(esc, ';'))
+ break;
+
+ esc++;
+
+ cgaddr = *(esc++) - '0';
+ if (cgaddr > 7) {
+ processed = 1;
+ break;
+ }
+
+ cgoffset = 0;
+ shift = 0;
+ value = 0;
+ while (*esc && cgoffset < 8) {
+ shift ^= 4;
+ if (*esc >= '0' && *esc <= '9') {
+ value |= (*esc - '0') << shift;
+ } else if (*esc >= 'A' && *esc <= 'Z') {
+ value |= (*esc - 'A' + 10) << shift;
+ } else if (*esc >= 'a' && *esc <= 'z') {
+ value |= (*esc - 'a' + 10) << shift;
+ } else {
+ esc++;
+ continue;
+ }
+
+ if (shift == 0) {
+ cgbytes[cgoffset++] = value;
+ value = 0;
+ }
+
+ esc++;
+ }
+
+ lcd->ops->write_cmd(lcd, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
+ for (addr = 0; addr < cgoffset; addr++)
+ lcd->ops->write_data(lcd, cgbytes[addr]);
+
+ /* ensures that we stop writing to CGRAM */
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+ case 'x': /* gotoxy : LxXXX[yYYY]; */
+ case 'y': /* gotoxy : LyYYY[xXXX]; */
+ if (!strchr(esc, ';'))
+ break;
+
+ while (*esc) {
+ if (*esc == 'x') {
+ esc++;
+ if (kstrtoul(esc, 10, &priv->addr.x) < 0)
+ break;
+ } else if (*esc == 'y') {
+ esc++;
+ if (kstrtoul(esc, 10, &priv->addr.y) < 0)
+ break;
+ } else {
+ break;
+ }
+ }
+
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+
+ /* TODO: This indent party here got ugly, clean it! */
+ /* Check whether one flag was changed */
+ if (oldflags == priv->flags)
+ return processed;
+
+ /* check whether one of B,C,D flags were changed */
+ if ((oldflags ^ priv->flags) &
+ (LCD_FLAG_B | LCD_FLAG_C | LCD_FLAG_D))
+ /* set display mode */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_DISPLAY_CTRL |
+ ((priv->flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0) |
+ ((priv->flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0) |
+ ((priv->flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0));
+ /* check whether one of F,N flags was changed */
+ else if ((oldflags ^ priv->flags) & (LCD_FLAG_F | LCD_FLAG_N))
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ ((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
+ /* check whether L flag was changed */
+ else if ((oldflags ^ priv->flags) & LCD_FLAG_L)
+ charlcd_backlight(lcd, !!(priv->flags & LCD_FLAG_L));
+
+ return processed;
+}
+
+static void charlcd_write_char(struct charlcd *lcd, char c)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ /* first, we'll test if we're in escape mode */
+ if ((c != '\n') && priv->esc_seq.len >= 0) {
+ /* yes, let's add this char to the buffer */
+ priv->esc_seq.buf[priv->esc_seq.len++] = c;
+ priv->esc_seq.buf[priv->esc_seq.len] = 0;
+ } else {
+ /* aborts any previous escape sequence */
+ priv->esc_seq.len = -1;
+
+ switch (c) {
+ case LCD_ESCAPE_CHAR:
+ /* start of an escape sequence */
+ priv->esc_seq.len = 0;
+ priv->esc_seq.buf[priv->esc_seq.len] = 0;
+ break;
+ case '\b':
+ /* go back one char and clear it */
+ if (priv->addr.x > 0) {
+ /*
+ * check if we're not at the
+ * end of the line
+ */
+ if (priv->addr.x < lcd->bwidth)
+ /* back one char */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ priv->addr.x--;
+ }
+ /* replace with a space */
+ lcd->ops->write_data(lcd, ' ');
+ /* back one char again */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ break;
+ case '\014':
+ /* quickly clear the display */
+ charlcd_clear_fast(lcd);
+ break;
+ case '\n':
+ /*
+ * flush the remainder of the current line and
+ * go to the beginning of the next line
+ */
+ for (; priv->addr.x < lcd->bwidth; priv->addr.x++)
+ lcd->ops->write_data(lcd, ' ');
+ priv->addr.x = 0;
+ priv->addr.y = (priv->addr.y + 1) % lcd->height;
+ charlcd_gotoxy(lcd);
+ break;
+ case '\r':
+ /* go to the beginning of the same line */
+ priv->addr.x = 0;
+ charlcd_gotoxy(lcd);
+ break;
+ case '\t':
+ /* print a space instead of the tab */
+ charlcd_print(lcd, ' ');
+ break;
+ default:
+ /* simply print this char */
+ charlcd_print(lcd, c);
+ break;
+ }
+ }
+
+ /*
+ * now we'll see if we're in an escape mode and if the current
+ * escape sequence can be understood.
+ */
+ if (priv->esc_seq.len >= 2) {
+ int processed = 0;
+
+ if (!strcmp(priv->esc_seq.buf, "[2J")) {
+ /* clear the display */
+ charlcd_clear_fast(lcd);
+ processed = 1;
+ } else if (!strcmp(priv->esc_seq.buf, "[H")) {
+ /* cursor to home */
+ charlcd_home(lcd);
+ processed = 1;
+ }
+ /* codes starting with ^[[L */
+ else if ((priv->esc_seq.len >= 3) &&
+ (priv->esc_seq.buf[0] == '[') &&
+ (priv->esc_seq.buf[1] == 'L')) {
+ processed = handle_lcd_special_code(lcd);
+ }
+
+ /* LCD special escape codes */
+ /*
+ * flush the escape sequence if it's been processed
+ * or if it is getting too long.
+ */
+ if (processed || (priv->esc_seq.len >= LCD_ESCAPE_LEN))
+ priv->esc_seq.len = -1;
+ } /* escape codes */
+}
+
+static struct charlcd *the_charlcd;
+
+static ssize_t charlcd_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ const char __user *tmp = buf;
+ char c;
+
+ for (; count-- > 0; (*ppos)++, tmp++) {
+ if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
+ /*
+ * let's be a little nice with other processes
+ * that need some CPU
+ */
+ schedule();
+
+ if (get_user(c, tmp))
+ return -EFAULT;
+
+ charlcd_write_char(the_charlcd, c);
+ }
+
+ return tmp - buf;
+}
+
+static int charlcd_open(struct inode *inode, struct file *file)
+{
+ struct charlcd_priv *priv = to_priv(the_charlcd);
+
+ if (!atomic_dec_and_test(&charlcd_available))
+ return -EBUSY; /* open only once at a time */
+
+ if (file->f_mode & FMODE_READ) /* device is write-only */
+ return -EPERM;
+
+ if (priv->must_clear) {
+ charlcd_clear_display(&priv->lcd);
+ priv->must_clear = false;
+ }
+ return nonseekable_open(inode, file);
+}
+
+static int charlcd_release(struct inode *inode, struct file *file)
+{
+ atomic_inc(&charlcd_available);
+ return 0;
+}
+
+static const struct file_operations charlcd_fops = {
+ .write = charlcd_write,
+ .open = charlcd_open,
+ .release = charlcd_release,
+ .llseek = no_llseek,
+};
+
+static struct miscdevice charlcd_dev = {
+ .minor = LCD_MINOR,
+ .name = "lcd",
+ .fops = &charlcd_fops,
+};
+
+static void charlcd_puts(struct charlcd *lcd, const char *s)
+{
+ const char *tmp = s;
+ int count = strlen(s);
+
+ for (; count-- > 0; tmp++) {
+ if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
+ /*
+ * let's be a little nice with other processes
+ * that need some CPU
+ */
+ schedule();
+
+ charlcd_write_char(lcd, *tmp);
+ }
+}
+
+/* initialize the LCD driver */
+static int charlcd_init(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+ int ret;
+
+ if (lcd->ops->backlight) {
+ mutex_init(&priv->bl_tempo_lock);
+ INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off);
+ }
+
+ /*
+ * before this line, we must NOT send anything to the display.
+ * Since charlcd_init_display() needs to write data, we have to
+ * enable mark the LCD initialized just before.
+ */
+ ret = charlcd_init_display(lcd);
+ if (ret)
+ return ret;
+
+ /* display a short message */
+#ifdef CONFIG_PANEL_CHANGE_MESSAGE
+#ifdef CONFIG_PANEL_BOOT_MESSAGE
+ charlcd_puts(lcd, "\x1b[Lc\x1b[Lb\x1b[L*" CONFIG_PANEL_BOOT_MESSAGE);
+#endif
+#else
+ charlcd_puts(lcd, "\x1b[Lc\x1b[Lb\x1b[L*Linux-" UTS_RELEASE "\n");
+#endif
+ /* clear the display on the next device opening */
+ priv->must_clear = true;
+ charlcd_home(lcd);
+ return 0;
+}
+
+struct charlcd *charlcd_alloc(unsigned int drvdata_size)
+{
+ struct charlcd_priv *priv;
+ struct charlcd *lcd;
+
+ priv = kzalloc(sizeof(*priv) + drvdata_size, GFP_KERNEL);
+ if (!priv)
+ return NULL;
+
+ priv->esc_seq.len = -1;
+
+ lcd = &priv->lcd;
+ lcd->bwidth = DEFAULT_LCD_BWIDTH;
+ lcd->hwidth = DEFAULT_LCD_HWIDTH;
+ lcd->drvdata = priv->drvdata;
+
+ return lcd;
+}
+EXPORT_SYMBOL_GPL(charlcd_alloc);
+
+static int panel_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ struct charlcd *lcd = the_charlcd;
+
+ switch (code) {
+ case SYS_DOWN:
+ charlcd_puts(lcd,
+ "\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ case SYS_HALT:
+ charlcd_puts(lcd, "\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ case SYS_POWER_OFF:
+ charlcd_puts(lcd, "\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block panel_notifier = {
+ panel_notify_sys,
+ NULL,
+ 0
+};
+
+int charlcd_register(struct charlcd *lcd)
+{
+ int ret;
+
+ ret = charlcd_init(lcd);
+ if (ret)
+ return ret;
+
+ ret = misc_register(&charlcd_dev);
+ if (ret)
+ return ret;
+
+ the_charlcd = lcd;
+ register_reboot_notifier(&panel_notifier);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_register);
+
+int charlcd_unregister(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ unregister_reboot_notifier(&panel_notifier);
+ charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
+ misc_deregister(&charlcd_dev);
+ the_charlcd = NULL;
+ if (lcd->ops->backlight) {
+ cancel_delayed_work_sync(&priv->bl_work);
+ priv->lcd.ops->backlight(&priv->lcd, 0);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_unregister);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index c290990d73edf87e..6e7bf55a542ebf8c 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -495,6 +495,7 @@ config VEXPRESS_SYSCFG
config PANEL
tristate "Parallel port LCD/Keypad Panel support"
depends on PARPORT
+ select CHARLCD
---help---
Say Y here if you have an HD44780 or KS-0074 LCD connected to your
parallel port. This driver also features 4 and 6-key keypads. The LCD
diff --git a/drivers/misc/panel.c b/drivers/misc/panel.c
index ef2ece0f26afc6b5..e0c014c2356ffb14 100644
--- a/drivers/misc/panel.c
+++ b/drivers/misc/panel.c
@@ -1,6 +1,7 @@
/*
* Front panel driver for Linux
* Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -54,15 +55,12 @@
#include <linux/ctype.h>
#include <linux/parport.h>
#include <linux/list.h>
-#include <linux/notifier.h>
-#include <linux/reboot.h>
-#include <linux/workqueue.h>
-#include <generated/utsrelease.h>
#include <linux/io.h>
#include <linux/uaccess.h>
-#define LCD_MINOR 156
+#include <misc/charlcd.h>
+
#define KEYPAD_MINOR 185
#define LCD_MAXBYTES 256 /* max burst write */
@@ -76,9 +74,6 @@
/* a key repeats this times INPUT_POLL_TIME */
#define KEYPAD_REP_DELAY (2)
-/* keep the light on this many seconds for each flash */
-#define FLASH_LIGHT_TEMPO (4)
-
/* converts an r_str() input to an active high, bits string : 000BAOSE */
#define PNL_PINPUT(a) ((((unsigned char)(a)) ^ 0x7F) >> 3)
@@ -120,40 +115,6 @@
#define PIN_SELECP 17
#define PIN_NOT_SET 127
-#define LCD_FLAG_B 0x0004 /* blink on */
-#define LCD_FLAG_C 0x0008 /* cursor on */
-#define LCD_FLAG_D 0x0010 /* display on */
-#define LCD_FLAG_F 0x0020 /* large font mode */
-#define LCD_FLAG_N 0x0040 /* 2-rows mode */
-#define LCD_FLAG_L 0x0080 /* backlight enabled */
-
-/* LCD commands */
-#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
-
-#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
-#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
-
-#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
-#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
-#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
-#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
-
-#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
-#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
-#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
-
-#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
-#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
-#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
-#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
-
-#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
-
-#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
-
-#define LCD_ESCAPE_LEN 24 /* max chars for LCD escape command */
-#define LCD_ESCAPE_CHAR 27 /* use char 27 for escape command */
-
#define NOT_SET -1
/* macros to simplify use of the parallel port */
@@ -245,19 +206,10 @@ static wait_queue_head_t keypad_read_wait;
static struct {
bool enabled;
bool initialized;
- bool must_clear;
- int height;
- int width;
- int bwidth;
- int hwidth;
int charset;
int proto;
- struct delayed_work bl_work;
- struct mutex bl_tempo_lock; /* Protects access to bl_tempo */
- bool bl_tempo;
-
/* TODO: use union here? */
struct {
int e;
@@ -268,20 +220,7 @@ static struct {
int bl;
} pins;
- /* contains the LCD config state */
- unsigned long int flags;
-
- /* Contains the LCD X and Y offset */
- struct {
- unsigned long int x;
- unsigned long int y;
- } addr;
-
- /* Current escape sequence and it's length or -1 if outside */
- struct {
- char buf[LCD_ESCAPE_LEN + 1];
- int len;
- } esc_seq;
+ struct charlcd *charlcd;
} lcd;
/* Needed only for init */
@@ -464,17 +403,12 @@ static unsigned char lcd_bits[LCD_PORTS][LCD_BITS][BIT_STATES];
/* global variables */
/* Device single-open policy control */
-static atomic_t lcd_available = ATOMIC_INIT(1);
static atomic_t keypad_available = ATOMIC_INIT(1);
static struct pardevice *pprt;
static int keypad_initialized;
-static void (*lcd_write_cmd)(int);
-static void (*lcd_write_data)(int);
-static void (*lcd_clear_fast)(void);
-
static DEFINE_SPINLOCK(pprt_lock);
static struct timer_list scan_timer;
@@ -574,8 +508,6 @@ static int keypad_enabled = NOT_SET;
module_param(keypad_enabled, int, 0000);
MODULE_PARM_DESC(keypad_enabled, "Deprecated option, use keypad_type instead");
-static const unsigned char *lcd_char_conv;
-
/* for some LCD drivers (ks0074) we need a charset conversion table. */
static const unsigned char lcd_char_conv_ks0074[256] = {
/* 0|8 1|9 2|A 3|B 4|C 5|D 6|E 7|F */
@@ -752,15 +684,6 @@ static void pin_to_bits(int pin, unsigned char *d_val, unsigned char *c_val)
}
}
-/* sleeps that many milliseconds with a reschedule */
-static void long_sleep(int ms)
-{
- if (in_interrupt())
- mdelay(ms);
- else
- schedule_timeout_interruptible(msecs_to_jiffies(ms));
-}
-
/*
* send a serial byte to the LCD panel. The caller is responsible for locking
* if needed.
@@ -792,8 +715,11 @@ static void lcd_send_serial(int byte)
}
/* turn the backlight on or off */
-static void __lcd_backlight(int on)
+static void lcd_backlight(struct charlcd *charlcd, int on)
{
+ if (lcd.pins.bl == PIN_NONE)
+ return;
+
/* The backlight is activated by setting the AUTOFEED line to +5V */
spin_lock_irq(&pprt_lock);
if (on)
@@ -804,46 +730,8 @@ static void __lcd_backlight(int on)
spin_unlock_irq(&pprt_lock);
}
-static void lcd_backlight(int on)
-{
- if (lcd.pins.bl == PIN_NONE)
- return;
-
- mutex_lock(&lcd.bl_tempo_lock);
- if (!lcd.bl_tempo)
- __lcd_backlight(on);
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
-static void lcd_bl_off(struct work_struct *work)
-{
- mutex_lock(&lcd.bl_tempo_lock);
- if (lcd.bl_tempo) {
- lcd.bl_tempo = false;
- if (!(lcd.flags & LCD_FLAG_L))
- __lcd_backlight(0);
- }
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
-/* turn the backlight on for a little while */
-static void lcd_poke(void)
-{
- if (lcd.pins.bl == PIN_NONE)
- return;
-
- cancel_delayed_work_sync(&lcd.bl_work);
-
- mutex_lock(&lcd.bl_tempo_lock);
- if (!lcd.bl_tempo && !(lcd.flags & LCD_FLAG_L))
- __lcd_backlight(1);
- lcd.bl_tempo = true;
- schedule_delayed_work(&lcd.bl_work, FLASH_LIGHT_TEMPO * HZ);
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
/* send a command to the LCD panel in serial mode */
-static void lcd_write_cmd_s(int cmd)
+static void lcd_write_cmd_s(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
lcd_send_serial(0x1F); /* R/W=W, RS=0 */
@@ -854,7 +742,7 @@ static void lcd_write_cmd_s(int cmd)
}
/* send data to the LCD panel in serial mode */
-static void lcd_write_data_s(int data)
+static void lcd_write_data_s(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
lcd_send_serial(0x5F); /* R/W=W, RS=1 */
@@ -865,7 +753,7 @@ static void lcd_write_data_s(int data)
}
/* send a command to the LCD panel in 8 bits parallel mode */
-static void lcd_write_cmd_p8(int cmd)
+static void lcd_write_cmd_p8(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -887,7 +775,7 @@ static void lcd_write_cmd_p8(int cmd)
}
/* send data to the LCD panel in 8 bits parallel mode */
-static void lcd_write_data_p8(int data)
+static void lcd_write_data_p8(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -909,7 +797,7 @@ static void lcd_write_data_p8(int data)
}
/* send a command to the TI LCD panel */
-static void lcd_write_cmd_tilcd(int cmd)
+static void lcd_write_cmd_tilcd(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
/* present the data to the control port */
@@ -919,7 +807,7 @@ static void lcd_write_cmd_tilcd(int cmd)
}
/* send data to the TI LCD panel */
-static void lcd_write_data_tilcd(int data)
+static void lcd_write_data_tilcd(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -928,47 +816,13 @@ static void lcd_write_data_tilcd(int data)
spin_unlock_irq(&pprt_lock);
}
-static void lcd_gotoxy(void)
-{
- lcd_write_cmd(LCD_CMD_SET_DDRAM_ADDR
- | (lcd.addr.y ? lcd.hwidth : 0)
- /*
- * we force the cursor to stay at the end of the
- * line if it wants to go farther
- */
- | ((lcd.addr.x < lcd.bwidth) ? lcd.addr.x &
- (lcd.hwidth - 1) : lcd.bwidth - 1));
-}
-
-static void lcd_home(void)
-{
- lcd.addr.x = 0;
- lcd.addr.y = 0;
- lcd_gotoxy();
-}
-
-static void lcd_print(char c)
-{
- if (lcd.addr.x < lcd.bwidth) {
- if (lcd_char_conv)
- c = lcd_char_conv[(unsigned char)c];
- lcd_write_data(c);
- lcd.addr.x++;
- }
- /* prevents the cursor from wrapping onto the next line */
- if (lcd.addr.x == lcd.bwidth)
- lcd_gotoxy();
-}
-
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_s(void)
+static void lcd_clear_fast_s(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
lcd_send_serial(0x5F); /* R/W=W, RS=1 */
lcd_send_serial(' ' & 0x0F);
lcd_send_serial((' ' >> 4) & 0x0F);
@@ -976,19 +830,15 @@ static void lcd_clear_fast_s(void)
udelay(40);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
}
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_p8(void)
+static void lcd_clear_fast_p8(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
@@ -1010,488 +860,62 @@ static void lcd_clear_fast_p8(void)
udelay(45);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
}
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_tilcd(void)
+static void lcd_clear_fast_tilcd(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
udelay(60);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
-}
-
-/* clears the display and resets X/Y */
-static void lcd_clear_display(void)
-{
- lcd_write_cmd(LCD_CMD_DISPLAY_CLEAR);
- lcd.addr.x = 0;
- lcd.addr.y = 0;
- /* we must wait a few milliseconds (15) */
- long_sleep(15);
}
-static void lcd_init_display(void)
-{
- lcd.flags = ((lcd.height > 1) ? LCD_FLAG_N : 0)
- | LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
-
- long_sleep(20); /* wait 20 ms after power-up for the paranoid */
-
- /* 8bits, 1 line, small fonts; let's do it 3 times */
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
-
- /* set font height and lines number */
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS
- | ((lcd.flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0)
- | ((lcd.flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0)
- );
- long_sleep(10);
-
- /* display off, cursor off, blink off */
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL);
- long_sleep(10);
-
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL /* set display mode */
- | ((lcd.flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0)
- | ((lcd.flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0)
- | ((lcd.flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0)
- );
-
- lcd_backlight((lcd.flags & LCD_FLAG_L) ? 1 : 0);
-
- long_sleep(10);
-
- /* entry mode set : increment, cursor shifting */
- lcd_write_cmd(LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+static struct charlcd_ops charlcd_serial_ops = {
+ .write_cmd = lcd_write_cmd_s,
+ .write_data = lcd_write_data_s,
+ .clear_fast = lcd_clear_fast_s,
+ .backlight = lcd_backlight,
+};
- lcd_clear_display();
-}
+static struct charlcd_ops charlcd_parallel_ops = {
+ .write_cmd = lcd_write_cmd_p8,
+ .write_data = lcd_write_data_p8,
+ .clear_fast = lcd_clear_fast_p8,
+ .backlight = lcd_backlight,
+};
-/*
- * These are the file operation function for user access to /dev/lcd
- * This function can also be called from inside the kernel, by
- * setting file and ppos to NULL.
- *
- */
+static struct charlcd_ops charlcd_tilcd_ops = {
+ .write_cmd = lcd_write_cmd_tilcd,
+ .write_data = lcd_write_data_tilcd,
+ .clear_fast = lcd_clear_fast_tilcd,
+ .backlight = lcd_backlight,
+};
-static inline int handle_lcd_special_code(void)
+/* initialize the LCD driver */
+static void lcd_init(void)
{
- /* LCD special codes */
-
- int processed = 0;
+ struct charlcd *charlcd;
- char *esc = lcd.esc_seq.buf + 2;
- int oldflags = lcd.flags;
-
- /* check for display mode flags */
- switch (*esc) {
- case 'D': /* Display ON */
- lcd.flags |= LCD_FLAG_D;
- processed = 1;
- break;
- case 'd': /* Display OFF */
- lcd.flags &= ~LCD_FLAG_D;
- processed = 1;
- break;
- case 'C': /* Cursor ON */
- lcd.flags |= LCD_FLAG_C;
- processed = 1;
- break;
- case 'c': /* Cursor OFF */
- lcd.flags &= ~LCD_FLAG_C;
- processed = 1;
- break;
- case 'B': /* Blink ON */
- lcd.flags |= LCD_FLAG_B;
- processed = 1;
- break;
- case 'b': /* Blink OFF */
- lcd.flags &= ~LCD_FLAG_B;
- processed = 1;
- break;
- case '+': /* Back light ON */
- lcd.flags |= LCD_FLAG_L;
- processed = 1;
- break;
- case '-': /* Back light OFF */
- lcd.flags &= ~LCD_FLAG_L;
- processed = 1;
- break;
- case '*':
- /* flash back light */
- lcd_poke();
- processed = 1;
- break;
- case 'f': /* Small Font */
- lcd.flags &= ~LCD_FLAG_F;
- processed = 1;
- break;
- case 'F': /* Large Font */
- lcd.flags |= LCD_FLAG_F;
- processed = 1;
- break;
- case 'n': /* One Line */
- lcd.flags &= ~LCD_FLAG_N;
- processed = 1;
- break;
- case 'N': /* Two Lines */
- lcd.flags |= LCD_FLAG_N;
- break;
- case 'l': /* Shift Cursor Left */
- if (lcd.addr.x > 0) {
- /* back one char if not at end of line */
- if (lcd.addr.x < lcd.bwidth)
- lcd_write_cmd(LCD_CMD_SHIFT);
- lcd.addr.x--;
- }
- processed = 1;
- break;
- case 'r': /* shift cursor right */
- if (lcd.addr.x < lcd.width) {
- /* allow the cursor to pass the end of the line */
- if (lcd.addr.x < (lcd.bwidth - 1))
- lcd_write_cmd(LCD_CMD_SHIFT |
- LCD_CMD_SHIFT_RIGHT);
- lcd.addr.x++;
- }
- processed = 1;
- break;
- case 'L': /* shift display left */
- lcd_write_cmd(LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
- processed = 1;
- break;
- case 'R': /* shift display right */
- lcd_write_cmd(LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
- LCD_CMD_SHIFT_RIGHT);
- processed = 1;
- break;
- case 'k': { /* kill end of line */
- int x;
-
- for (x = lcd.addr.x; x < lcd.bwidth; x++)
- lcd_write_data(' ');
-
- /* restore cursor position */
- lcd_gotoxy();
- processed = 1;
- break;
- }
- case 'I': /* reinitialize display */
- lcd_init_display();
- processed = 1;
- break;
- case 'G': {
- /* Generator : LGcxxxxx...xx; must have <c> between '0'
- * and '7', representing the numerical ASCII code of the
- * redefined character, and <xx...xx> a sequence of 16
- * hex digits representing 8 bytes for each character.
- * Most LCDs will only use 5 lower bits of the 7 first
- * bytes.
- */
-
- unsigned char cgbytes[8];
- unsigned char cgaddr;
- int cgoffset;
- int shift;
- char value;
- int addr;
-
- if (!strchr(esc, ';'))
- break;
-
- esc++;
-
- cgaddr = *(esc++) - '0';
- if (cgaddr > 7) {
- processed = 1;
- break;
- }
-
- cgoffset = 0;
- shift = 0;
- value = 0;
- while (*esc && cgoffset < 8) {
- shift ^= 4;
- if (*esc >= '0' && *esc <= '9') {
- value |= (*esc - '0') << shift;
- } else if (*esc >= 'A' && *esc <= 'Z') {
- value |= (*esc - 'A' + 10) << shift;
- } else if (*esc >= 'a' && *esc <= 'z') {
- value |= (*esc - 'a' + 10) << shift;
- } else {
- esc++;
- continue;
- }
-
- if (shift == 0) {
- cgbytes[cgoffset++] = value;
- value = 0;
- }
-
- esc++;
- }
-
- lcd_write_cmd(LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
- for (addr = 0; addr < cgoffset; addr++)
- lcd_write_data(cgbytes[addr]);
-
- /* ensures that we stop writing to CGRAM */
- lcd_gotoxy();
- processed = 1;
- break;
- }
- case 'x': /* gotoxy : LxXXX[yYYY]; */
- case 'y': /* gotoxy : LyYYY[xXXX]; */
- if (!strchr(esc, ';'))
- break;
-
- while (*esc) {
- if (*esc == 'x') {
- esc++;
- if (kstrtoul(esc, 10, &lcd.addr.x) < 0)
- break;
- } else if (*esc == 'y') {
- esc++;
- if (kstrtoul(esc, 10, &lcd.addr.y) < 0)
- break;
- } else {
- break;
- }
- }
-
- lcd_gotoxy();
- processed = 1;
- break;
- }
-
- /* TODO: This indent party here got ugly, clean it! */
- /* Check whether one flag was changed */
- if (oldflags != lcd.flags) {
- /* check whether one of B,C,D flags were changed */
- if ((oldflags ^ lcd.flags) &
- (LCD_FLAG_B | LCD_FLAG_C | LCD_FLAG_D))
- /* set display mode */
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL
- | ((lcd.flags & LCD_FLAG_D)
- ? LCD_CMD_DISPLAY_ON : 0)
- | ((lcd.flags & LCD_FLAG_C)
- ? LCD_CMD_CURSOR_ON : 0)
- | ((lcd.flags & LCD_FLAG_B)
- ? LCD_CMD_BLINK_ON : 0));
- /* check whether one of F,N flags was changed */
- else if ((oldflags ^ lcd.flags) & (LCD_FLAG_F | LCD_FLAG_N))
- lcd_write_cmd(LCD_CMD_FUNCTION_SET
- | LCD_CMD_DATA_LEN_8BITS
- | ((lcd.flags & LCD_FLAG_F)
- ? LCD_CMD_FONT_5X10_DOTS
- : 0)
- | ((lcd.flags & LCD_FLAG_N)
- ? LCD_CMD_TWO_LINES
- : 0));
- /* check whether L flag was changed */
- else if ((oldflags ^ lcd.flags) & (LCD_FLAG_L))
- lcd_backlight(!!(lcd.flags & LCD_FLAG_L));
- }
-
- return processed;
-}
-
-static void lcd_write_char(char c)
-{
- /* first, we'll test if we're in escape mode */
- if ((c != '\n') && lcd.esc_seq.len >= 0) {
- /* yes, let's add this char to the buffer */
- lcd.esc_seq.buf[lcd.esc_seq.len++] = c;
- lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
- } else {
- /* aborts any previous escape sequence */
- lcd.esc_seq.len = -1;
-
- switch (c) {
- case LCD_ESCAPE_CHAR:
- /* start of an escape sequence */
- lcd.esc_seq.len = 0;
- lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
- break;
- case '\b':
- /* go back one char and clear it */
- if (lcd.addr.x > 0) {
- /*
- * check if we're not at the
- * end of the line
- */
- if (lcd.addr.x < lcd.bwidth)
- /* back one char */
- lcd_write_cmd(LCD_CMD_SHIFT);
- lcd.addr.x--;
- }
- /* replace with a space */
- lcd_write_data(' ');
- /* back one char again */
- lcd_write_cmd(LCD_CMD_SHIFT);
- break;
- case '\014':
- /* quickly clear the display */
- lcd_clear_fast();
- break;
- case '\n':
- /*
- * flush the remainder of the current line and
- * go to the beginning of the next line
- */
- for (; lcd.addr.x < lcd.bwidth; lcd.addr.x++)
- lcd_write_data(' ');
- lcd.addr.x = 0;
- lcd.addr.y = (lcd.addr.y + 1) % lcd.height;
- lcd_gotoxy();
- break;
- case '\r':
- /* go to the beginning of the same line */
- lcd.addr.x = 0;
- lcd_gotoxy();
- break;
- case '\t':
- /* print a space instead of the tab */
- lcd_print(' ');
- break;
- default:
- /* simply print this char */
- lcd_print(c);
- break;
- }
- }
+ charlcd = charlcd_alloc(0);
+ if (!charlcd)
+ return;
/*
- * now we'll see if we're in an escape mode and if the current
- * escape sequence can be understood.
+ * Init lcd struct with load-time values to preserve exact
+ * current functionality (at least for now).
*/
- if (lcd.esc_seq.len >= 2) {
- int processed = 0;
-
- if (!strcmp(lcd.esc_seq.buf, "[2J")) {
- /* clear the display */
- lcd_clear_fast();
- processed = 1;
- } else if (!strcmp(lcd.esc_seq.buf, "[H")) {
- /* cursor to home */
- lcd_home();
- processed = 1;
- }
- /* codes starting with ^[[L */
- else if ((lcd.esc_seq.len >= 3) &&
- (lcd.esc_seq.buf[0] == '[') &&
- (lcd.esc_seq.buf[1] == 'L')) {
- processed = handle_lcd_special_code();
- }
-
- /* LCD special escape codes */
- /*
- * flush the escape sequence if it's been processed
- * or if it is getting too long.
- */
- if (processed || (lcd.esc_seq.len >= LCD_ESCAPE_LEN))
- lcd.esc_seq.len = -1;
- } /* escape codes */
-}
+ charlcd->height = lcd_height;
+ charlcd->width = lcd_width;
+ charlcd->bwidth = lcd_bwidth;
+ charlcd->hwidth = lcd_hwidth;
-static ssize_t lcd_write(struct file *file,
- const char __user *buf, size_t count, loff_t *ppos)
-{
- const char __user *tmp = buf;
- char c;
-
- for (; count-- > 0; (*ppos)++, tmp++) {
- if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
- /*
- * let's be a little nice with other processes
- * that need some CPU
- */
- schedule();
-
- if (get_user(c, tmp))
- return -EFAULT;
-
- lcd_write_char(c);
- }
-
- return tmp - buf;
-}
-
-static int lcd_open(struct inode *inode, struct file *file)
-{
- if (!atomic_dec_and_test(&lcd_available))
- return -EBUSY; /* open only once at a time */
-
- if (file->f_mode & FMODE_READ) /* device is write-only */
- return -EPERM;
-
- if (lcd.must_clear) {
- lcd_clear_display();
- lcd.must_clear = false;
- }
- return nonseekable_open(inode, file);
-}
-
-static int lcd_release(struct inode *inode, struct file *file)
-{
- atomic_inc(&lcd_available);
- return 0;
-}
-
-static const struct file_operations lcd_fops = {
- .write = lcd_write,
- .open = lcd_open,
- .release = lcd_release,
- .llseek = no_llseek,
-};
-
-static struct miscdevice lcd_dev = {
- .minor = LCD_MINOR,
- .name = "lcd",
- .fops = &lcd_fops,
-};
-
-/* public function usable from the kernel for any purpose */
-static void panel_lcd_print(const char *s)
-{
- const char *tmp = s;
- int count = strlen(s);
-
- if (lcd.enabled && lcd.initialized) {
- for (; count-- > 0; tmp++) {
- if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
- /*
- * let's be a little nice with other processes
- * that need some CPU
- */
- schedule();
-
- lcd_write_char(*tmp);
- }
- }
-}
-
-/* initialize the LCD driver */
-static void lcd_init(void)
-{
switch (selected_lcd_type) {
case LCD_TYPE_OLD:
/* parallel mode, 8 bits */
@@ -1500,10 +924,10 @@ static void lcd_init(void)
lcd.pins.e = PIN_STROBE;
lcd.pins.rs = PIN_AUTOLF;
- lcd.width = 40;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 40;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
case LCD_TYPE_KS0074:
/* serial mode, ks0074 */
@@ -1513,10 +937,10 @@ static void lcd_init(void)
lcd.pins.cl = PIN_STROBE;
lcd.pins.da = PIN_D0;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 16;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 16;
+ charlcd->height = 2;
break;
case LCD_TYPE_NEXCOM:
/* parallel mode, 8 bits, generic */
@@ -1526,10 +950,10 @@ static void lcd_init(void)
lcd.pins.rs = PIN_SELECP;
lcd.pins.rw = PIN_INITP;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
case LCD_TYPE_CUSTOM:
/* customer-defined */
@@ -1545,22 +969,22 @@ static void lcd_init(void)
lcd.pins.e = PIN_STROBE;
lcd.pins.rs = PIN_SELECP;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
}
/* Overwrite with module params set on loading */
if (lcd_height != NOT_SET)
- lcd.height = lcd_height;
+ charlcd->height = lcd_height;
if (lcd_width != NOT_SET)
- lcd.width = lcd_width;
+ charlcd->width = lcd_width;
if (lcd_bwidth != NOT_SET)
- lcd.bwidth = lcd_bwidth;
+ charlcd->bwidth = lcd_bwidth;
if (lcd_hwidth != NOT_SET)
- lcd.hwidth = lcd_hwidth;
+ charlcd->hwidth = lcd_hwidth;
if (lcd_charset != NOT_SET)
lcd.charset = lcd_charset;
if (lcd_proto != NOT_SET)
@@ -1579,19 +1003,17 @@ static void lcd_init(void)
lcd.pins.bl = lcd_bl_pin;
/* this is used to catch wrong and default values */
- if (lcd.width <= 0)
- lcd.width = DEFAULT_LCD_WIDTH;
- if (lcd.bwidth <= 0)
- lcd.bwidth = DEFAULT_LCD_BWIDTH;
- if (lcd.hwidth <= 0)
- lcd.hwidth = DEFAULT_LCD_HWIDTH;
- if (lcd.height <= 0)
- lcd.height = DEFAULT_LCD_HEIGHT;
+ if (charlcd->width <= 0)
+ charlcd->width = DEFAULT_LCD_WIDTH;
+ if (charlcd->bwidth <= 0)
+ charlcd->bwidth = DEFAULT_LCD_BWIDTH;
+ if (charlcd->hwidth <= 0)
+ charlcd->hwidth = DEFAULT_LCD_HWIDTH;
+ if (charlcd->height <= 0)
+ charlcd->height = DEFAULT_LCD_HEIGHT;
if (lcd.proto == LCD_PROTO_SERIAL) { /* SERIAL */
- lcd_write_cmd = lcd_write_cmd_s;
- lcd_write_data = lcd_write_data_s;
- lcd_clear_fast = lcd_clear_fast_s;
+ charlcd->ops = &charlcd_serial_ops;
if (lcd.pins.cl == PIN_NOT_SET)
lcd.pins.cl = DEFAULT_LCD_PIN_SCL;
@@ -1599,9 +1021,7 @@ static void lcd_init(void)
lcd.pins.da = DEFAULT_LCD_PIN_SDA;
} else if (lcd.proto == LCD_PROTO_PARALLEL) { /* PARALLEL */
- lcd_write_cmd = lcd_write_cmd_p8;
- lcd_write_data = lcd_write_data_p8;
- lcd_clear_fast = lcd_clear_fast_p8;
+ charlcd->ops = &charlcd_parallel_ops;
if (lcd.pins.e == PIN_NOT_SET)
lcd.pins.e = DEFAULT_LCD_PIN_E;
@@ -1610,9 +1030,7 @@ static void lcd_init(void)
if (lcd.pins.rw == PIN_NOT_SET)
lcd.pins.rw = DEFAULT_LCD_PIN_RW;
} else {
- lcd_write_cmd = lcd_write_cmd_tilcd;
- lcd_write_data = lcd_write_data_tilcd;
- lcd_clear_fast = lcd_clear_fast_tilcd;
+ charlcd->ops = &charlcd_tilcd_ops;
}
if (lcd.pins.bl == PIN_NOT_SET)
@@ -1635,14 +1053,9 @@ static void lcd_init(void)
lcd.charset = DEFAULT_LCD_CHARSET;
if (lcd.charset == LCD_CHARSET_KS0074)
- lcd_char_conv = lcd_char_conv_ks0074;
+ charlcd->char_conv = lcd_char_conv_ks0074;
else
- lcd_char_conv = NULL;
-
- if (lcd.pins.bl != PIN_NONE) {
- mutex_init(&lcd.bl_tempo_lock);
- INIT_DELAYED_WORK(&lcd.bl_work, lcd_bl_off);
- }
+ charlcd->char_conv = NULL;
pin_to_bits(lcd.pins.e, lcd_bits[LCD_PORT_D][LCD_BIT_E],
lcd_bits[LCD_PORT_C][LCD_BIT_E]);
@@ -1657,25 +1070,8 @@ static void lcd_init(void)
pin_to_bits(lcd.pins.da, lcd_bits[LCD_PORT_D][LCD_BIT_DA],
lcd_bits[LCD_PORT_C][LCD_BIT_DA]);
- /*
- * before this line, we must NOT send anything to the display.
- * Since lcd_init_display() needs to write data, we have to
- * enable mark the LCD initialized just before.
- */
+ lcd.charlcd = charlcd;
lcd.initialized = true;
- lcd_init_display();
-
- /* display a short message */
-#ifdef CONFIG_PANEL_CHANGE_MESSAGE
-#ifdef CONFIG_PANEL_BOOT_MESSAGE
- panel_lcd_print("\x1b[Lc\x1b[Lb\x1b[L*" CONFIG_PANEL_BOOT_MESSAGE);
-#endif
-#else
- panel_lcd_print("\x1b[Lc\x1b[Lb\x1b[L*Linux-" UTS_RELEASE);
-#endif
- /* clear the display on the next device opening */
- lcd.must_clear = true;
- lcd_home();
}
/*
@@ -2011,7 +1407,7 @@ static void panel_scan_timer(void)
}
if (keypressed && lcd.enabled && lcd.initialized)
- lcd_poke();
+ charlcd_poke(lcd.charlcd);
mod_timer(&scan_timer, jiffies + INPUT_POLL_TIME);
}
@@ -2175,35 +1571,6 @@ static void keypad_init(void)
/* device initialization */
/**************************************************/
-static int panel_notify_sys(struct notifier_block *this, unsigned long code,
- void *unused)
-{
- if (lcd.enabled && lcd.initialized) {
- switch (code) {
- case SYS_DOWN:
- panel_lcd_print
- ("\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- case SYS_HALT:
- panel_lcd_print
- ("\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- case SYS_POWER_OFF:
- panel_lcd_print("\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- default:
- break;
- }
- }
- return NOTIFY_DONE;
-}
-
-static struct notifier_block panel_notifier = {
- panel_notify_sys,
- NULL,
- 0
-};
-
static void panel_attach(struct parport *port)
{
struct pardev_cb panel_cb;
@@ -2239,7 +1606,7 @@ static void panel_attach(struct parport *port)
*/
if (lcd.enabled) {
lcd_init();
- if (misc_register(&lcd_dev))
+ if (!lcd.charlcd || charlcd_register(lcd.charlcd))
goto err_unreg_device;
}
@@ -2248,13 +1615,14 @@ static void panel_attach(struct parport *port)
if (misc_register(&keypad_dev))
goto err_lcd_unreg;
}
- register_reboot_notifier(&panel_notifier);
return;
err_lcd_unreg:
if (lcd.enabled)
- misc_deregister(&lcd_dev);
+ charlcd_unregister(lcd.charlcd);
err_unreg_device:
+ kfree(lcd.charlcd);
+ lcd.charlcd = NULL;
parport_unregister_device(pprt);
pprt = NULL;
}
@@ -2278,20 +1646,16 @@ static void panel_detach(struct parport *port)
}
if (lcd.enabled) {
- panel_lcd_print("\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
- misc_deregister(&lcd_dev);
- if (lcd.pins.bl != PIN_NONE) {
- cancel_delayed_work_sync(&lcd.bl_work);
- __lcd_backlight(0);
- }
+ charlcd_unregister(lcd.charlcd);
lcd.initialized = false;
+ kfree(lcd.charlcd);
+ lcd.charlcd = NULL;
}
/* TODO: free all input signals */
parport_release(pprt);
parport_unregister_device(pprt);
pprt = NULL;
- unregister_reboot_notifier(&panel_notifier);
}
static struct parport_driver panel_driver = {
@@ -2369,10 +1733,6 @@ static int __init panel_init_module(void)
* Init lcd struct with load-time values to preserve exact
* current functionality (at least for now).
*/
- lcd.height = lcd_height;
- lcd.width = lcd_width;
- lcd.bwidth = lcd_bwidth;
- lcd.hwidth = lcd_hwidth;
lcd.charset = lcd_charset;
lcd.proto = lcd_proto;
lcd.pins.e = lcd_e_pin;
@@ -2381,9 +1741,6 @@ static int __init panel_init_module(void)
lcd.pins.cl = lcd_cl_pin;
lcd.pins.da = lcd_da_pin;
lcd.pins.bl = lcd_bl_pin;
-
- /* Leave it for now, just in case */
- lcd.esc_seq.len = -1;
}
switch (selected_keypad_type) {
diff --git a/include/misc/charlcd.h b/include/misc/charlcd.h
new file mode 100644
index 0000000000000000..c40047b673c9ea09
--- /dev/null
+++ b/include/misc/charlcd.h
@@ -0,0 +1,40 @@
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+struct charlcd {
+ const struct charlcd_ops *ops;
+ const unsigned char *char_conv; /* Optional */
+
+ int height;
+ int width;
+ int bwidth; /* Default set by charlcd_alloc() */
+ int hwidth; /* Default set by charlcd_alloc() */
+
+ void *drvdata; /* Set by charlcd_alloc() */
+};
+
+struct charlcd_ops {
+ /* Required */
+ void (*write_cmd)(struct charlcd *lcd, int cmd);
+ void (*write_data)(struct charlcd *lcd, int data);
+
+ /* Optional */
+ void (*clear_fast)(struct charlcd *lcd);
+ void (*backlight)(struct charlcd *lcd, int on);
+};
+
+struct charlcd *charlcd_alloc(unsigned int drvdata_size);
+
+int charlcd_register(struct charlcd *lcd);
+int charlcd_unregister(struct charlcd *lcd);
+
+void charlcd_poke(struct charlcd *lcd);
--
2.7.4
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 1/5] auxdisplay: charlcd: Extract character LCD core from misc/panel
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Geert Uytterhoeven
Extract the character LCD core from the Parallel port LCD/Keypad Panel
driver in the misc subsystem, and convert it into a subdriver in the
auxdisplay subsystem. This allows the character LCD core to be used by
other drivers later.
Compilation is controlled by its own Kconfig symbol CHARLCD, which is to
be selected by its users, but can be enabled manually for
compile-testing.
All functions changed their prefix from "lcd_" to "charlcd_", and gained
a "struct charlcd *" parameter to operate on a specific instance.
While the driver API thus is ready to support multiple instances, the
current limitation of a single display (/dev/lcd has a single misc minor
assigned) is retained.
No functional changes intended.
Signed-off-by: Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>
---
v2:
- Move backlight mutex initialization before call to
charlcd_init_display(), to prevent locking an uninitialized mutex
(reported by 0day).
---
drivers/auxdisplay/Kconfig | 3 +
drivers/auxdisplay/Makefile | 1 +
drivers/auxdisplay/charlcd.c | 790 +++++++++++++++++++++++++++++++++++++++++
drivers/misc/Kconfig | 1 +
drivers/misc/panel.c | 827 +++++--------------------------------------
include/misc/charlcd.h | 40 +++
6 files changed, 927 insertions(+), 735 deletions(-)
create mode 100644 drivers/auxdisplay/charlcd.c
create mode 100644 include/misc/charlcd.h
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
index 8a8e403644d6e0d6..b4686380d4e3cca9 100644
--- a/drivers/auxdisplay/Kconfig
+++ b/drivers/auxdisplay/Kconfig
@@ -13,6 +13,9 @@ menuconfig AUXDISPLAY
If you say N, all options in this submenu will be skipped and disabled.
+config CHARLCD
+ tristate "Character LCD core support" if COMPILE_TEST
+
if AUXDISPLAY
config KS0108
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
index cb3dd847713bb6d1..f56f45dcc78e332e 100644
--- a/drivers/auxdisplay/Makefile
+++ b/drivers/auxdisplay/Makefile
@@ -2,6 +2,7 @@
# Makefile for the kernel auxiliary displays device drivers.
#
+obj-$(CONFIG_CHARLCD) += charlcd.o
obj-$(CONFIG_KS0108) += ks0108.o
obj-$(CONFIG_CFAG12864B) += cfag12864b.o cfag12864bfb.o
obj-$(CONFIG_IMG_ASCII_LCD) += img-ascii-lcd.o
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
new file mode 100644
index 0000000000000000..930ffb2fb31787c5
--- /dev/null
+++ b/drivers/auxdisplay/charlcd.c
@@ -0,0 +1,790 @@
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/atomic.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+
+#include <generated/utsrelease.h>
+
+#include <misc/charlcd.h>
+
+#define LCD_MINOR 156
+
+#define DEFAULT_LCD_BWIDTH 40
+#define DEFAULT_LCD_HWIDTH 64
+
+/* Keep the backlight on this many seconds for each flash */
+#define LCD_BL_TEMPO_PERIOD 4
+
+#define LCD_FLAG_B 0x0004 /* Blink on */
+#define LCD_FLAG_C 0x0008 /* Cursor on */
+#define LCD_FLAG_D 0x0010 /* Display on */
+#define LCD_FLAG_F 0x0020 /* Large font mode */
+#define LCD_FLAG_N 0x0040 /* 2-rows mode */
+#define LCD_FLAG_L 0x0080 /* Backlight enabled */
+
+/* LCD commands */
+#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
+
+#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
+#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
+
+#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
+#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
+#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
+#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
+
+#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
+#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
+#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
+
+#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
+#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
+#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
+#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
+
+#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
+
+#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
+
+#define LCD_ESCAPE_LEN 24 /* Max chars for LCD escape command */
+#define LCD_ESCAPE_CHAR 27 /* Use char 27 for escape command */
+
+struct charlcd_priv {
+ struct charlcd lcd;
+
+ struct delayed_work bl_work;
+ struct mutex bl_tempo_lock; /* Protects access to bl_tempo */
+ bool bl_tempo;
+
+ bool must_clear;
+
+ /* contains the LCD config state */
+ unsigned long int flags;
+
+ /* Contains the LCD X and Y offset */
+ struct {
+ unsigned long int x;
+ unsigned long int y;
+ } addr;
+
+ /* Current escape sequence and it's length or -1 if outside */
+ struct {
+ char buf[LCD_ESCAPE_LEN + 1];
+ int len;
+ } esc_seq;
+
+ unsigned long long drvdata[0];
+};
+
+#define to_priv(p) container_of(p, struct charlcd_priv, lcd)
+
+/* Device single-open policy control */
+static atomic_t charlcd_available = ATOMIC_INIT(1);
+
+/* sleeps that many milliseconds with a reschedule */
+static void long_sleep(int ms)
+{
+ if (in_interrupt())
+ mdelay(ms);
+ else
+ schedule_timeout_interruptible(msecs_to_jiffies(ms));
+}
+
+/* turn the backlight on or off */
+static void charlcd_backlight(struct charlcd *lcd, int on)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (!lcd->ops->backlight)
+ return;
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (!priv->bl_tempo)
+ lcd->ops->backlight(lcd, on);
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+
+static void charlcd_bl_off(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct charlcd_priv *priv =
+ container_of(dwork, struct charlcd_priv, bl_work);
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (priv->bl_tempo) {
+ priv->bl_tempo = false;
+ if (!(priv->flags & LCD_FLAG_L))
+ priv->lcd.ops->backlight(&priv->lcd, 0);
+ }
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+
+/* turn the backlight on for a little while */
+void charlcd_poke(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (!lcd->ops->backlight)
+ return;
+
+ cancel_delayed_work_sync(&priv->bl_work);
+
+ mutex_lock(&priv->bl_tempo_lock);
+ if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L))
+ lcd->ops->backlight(lcd, 1);
+ priv->bl_tempo = true;
+ schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ);
+ mutex_unlock(&priv->bl_tempo_lock);
+}
+EXPORT_SYMBOL_GPL(charlcd_poke);
+
+static void charlcd_gotoxy(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SET_DDRAM_ADDR | (priv->addr.y ? lcd->hwidth : 0) |
+ /*
+ * we force the cursor to stay at the end of the
+ * line if it wants to go farther
+ */
+ ((priv->addr.x < lcd->bwidth) ? priv->addr.x & (lcd->hwidth - 1)
+ : lcd->bwidth - 1));
+}
+
+static void charlcd_home(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ priv->addr.x = 0;
+ priv->addr.y = 0;
+ charlcd_gotoxy(lcd);
+}
+
+static void charlcd_print(struct charlcd *lcd, char c)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ if (priv->addr.x < lcd->bwidth) {
+ if (lcd->char_conv)
+ c = lcd->char_conv[(unsigned char)c];
+ lcd->ops->write_data(lcd, c);
+ priv->addr.x++;
+ }
+ /* prevents the cursor from wrapping onto the next line */
+ if (priv->addr.x == lcd->bwidth)
+ charlcd_gotoxy(lcd);
+}
+
+static void charlcd_clear_fast(struct charlcd *lcd)
+{
+ int pos;
+
+ charlcd_home(lcd);
+
+ if (lcd->ops->clear_fast)
+ lcd->ops->clear_fast(lcd);
+ else
+ for (pos = 0; pos < lcd->height * lcd->hwidth; pos++)
+ lcd->ops->write_data(lcd, ' ');
+
+ charlcd_home(lcd);
+}
+
+/* clears the display and resets X/Y */
+static void charlcd_clear_display(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ lcd->ops->write_cmd(lcd, LCD_CMD_DISPLAY_CLEAR);
+ priv->addr.x = 0;
+ priv->addr.y = 0;
+ /* we must wait a few milliseconds (15) */
+ long_sleep(15);
+}
+
+static int charlcd_init_display(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+ LCD_FLAG_C | LCD_FLAG_B;
+
+ long_sleep(20); /* wait 20 ms after power-up for the paranoid */
+
+ /* 8bits, 1 line, small fonts; let's do it 3 times */
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+ lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ long_sleep(10);
+
+ /* set font height and lines number */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ ((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
+ long_sleep(10);
+
+ /* display off, cursor off, blink off */
+ lcd->ops->write_cmd(lcd, LCD_CMD_DISPLAY_CTRL);
+ long_sleep(10);
+
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_DISPLAY_CTRL | /* set display mode */
+ ((priv->flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0) |
+ ((priv->flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0) |
+ ((priv->flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0));
+
+ charlcd_backlight(lcd, (priv->flags & LCD_FLAG_L) ? 1 : 0);
+
+ long_sleep(10);
+
+ /* entry mode set : increment, cursor shifting */
+ lcd->ops->write_cmd(lcd, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+
+ charlcd_clear_display(lcd);
+ return 0;
+}
+
+/*
+ * These are the file operation function for user access to /dev/lcd
+ * This function can also be called from inside the kernel, by
+ * setting file and ppos to NULL.
+ *
+ */
+
+static inline int handle_lcd_special_code(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ /* LCD special codes */
+
+ int processed = 0;
+
+ char *esc = priv->esc_seq.buf + 2;
+ int oldflags = priv->flags;
+
+ /* check for display mode flags */
+ switch (*esc) {
+ case 'D': /* Display ON */
+ priv->flags |= LCD_FLAG_D;
+ processed = 1;
+ break;
+ case 'd': /* Display OFF */
+ priv->flags &= ~LCD_FLAG_D;
+ processed = 1;
+ break;
+ case 'C': /* Cursor ON */
+ priv->flags |= LCD_FLAG_C;
+ processed = 1;
+ break;
+ case 'c': /* Cursor OFF */
+ priv->flags &= ~LCD_FLAG_C;
+ processed = 1;
+ break;
+ case 'B': /* Blink ON */
+ priv->flags |= LCD_FLAG_B;
+ processed = 1;
+ break;
+ case 'b': /* Blink OFF */
+ priv->flags &= ~LCD_FLAG_B;
+ processed = 1;
+ break;
+ case '+': /* Back light ON */
+ priv->flags |= LCD_FLAG_L;
+ processed = 1;
+ break;
+ case '-': /* Back light OFF */
+ priv->flags &= ~LCD_FLAG_L;
+ processed = 1;
+ break;
+ case '*': /* Flash back light */
+ charlcd_poke(lcd);
+ processed = 1;
+ break;
+ case 'f': /* Small Font */
+ priv->flags &= ~LCD_FLAG_F;
+ processed = 1;
+ break;
+ case 'F': /* Large Font */
+ priv->flags |= LCD_FLAG_F;
+ processed = 1;
+ break;
+ case 'n': /* One Line */
+ priv->flags &= ~LCD_FLAG_N;
+ processed = 1;
+ break;
+ case 'N': /* Two Lines */
+ priv->flags |= LCD_FLAG_N;
+ break;
+ case 'l': /* Shift Cursor Left */
+ if (priv->addr.x > 0) {
+ /* back one char if not at end of line */
+ if (priv->addr.x < lcd->bwidth)
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ priv->addr.x--;
+ }
+ processed = 1;
+ break;
+ case 'r': /* shift cursor right */
+ if (priv->addr.x < lcd->width) {
+ /* allow the cursor to pass the end of the line */
+ if (priv->addr.x < (lcd->bwidth - 1))
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
+ priv->addr.x++;
+ }
+ processed = 1;
+ break;
+ case 'L': /* shift display left */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+ processed = 1;
+ break;
+ case 'R': /* shift display right */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
+ LCD_CMD_SHIFT_RIGHT);
+ processed = 1;
+ break;
+ case 'k': { /* kill end of line */
+ int x;
+
+ for (x = priv->addr.x; x < lcd->bwidth; x++)
+ lcd->ops->write_data(lcd, ' ');
+
+ /* restore cursor position */
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+ case 'I': /* reinitialize display */
+ charlcd_init_display(lcd);
+ processed = 1;
+ break;
+ case 'G': {
+ /* Generator : LGcxxxxx...xx; must have <c> between '0'
+ * and '7', representing the numerical ASCII code of the
+ * redefined character, and <xx...xx> a sequence of 16
+ * hex digits representing 8 bytes for each character.
+ * Most LCDs will only use 5 lower bits of the 7 first
+ * bytes.
+ */
+
+ unsigned char cgbytes[8];
+ unsigned char cgaddr;
+ int cgoffset;
+ int shift;
+ char value;
+ int addr;
+
+ if (!strchr(esc, ';'))
+ break;
+
+ esc++;
+
+ cgaddr = *(esc++) - '0';
+ if (cgaddr > 7) {
+ processed = 1;
+ break;
+ }
+
+ cgoffset = 0;
+ shift = 0;
+ value = 0;
+ while (*esc && cgoffset < 8) {
+ shift ^= 4;
+ if (*esc >= '0' && *esc <= '9') {
+ value |= (*esc - '0') << shift;
+ } else if (*esc >= 'A' && *esc <= 'Z') {
+ value |= (*esc - 'A' + 10) << shift;
+ } else if (*esc >= 'a' && *esc <= 'z') {
+ value |= (*esc - 'a' + 10) << shift;
+ } else {
+ esc++;
+ continue;
+ }
+
+ if (shift == 0) {
+ cgbytes[cgoffset++] = value;
+ value = 0;
+ }
+
+ esc++;
+ }
+
+ lcd->ops->write_cmd(lcd, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
+ for (addr = 0; addr < cgoffset; addr++)
+ lcd->ops->write_data(lcd, cgbytes[addr]);
+
+ /* ensures that we stop writing to CGRAM */
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+ case 'x': /* gotoxy : LxXXX[yYYY]; */
+ case 'y': /* gotoxy : LyYYY[xXXX]; */
+ if (!strchr(esc, ';'))
+ break;
+
+ while (*esc) {
+ if (*esc == 'x') {
+ esc++;
+ if (kstrtoul(esc, 10, &priv->addr.x) < 0)
+ break;
+ } else if (*esc == 'y') {
+ esc++;
+ if (kstrtoul(esc, 10, &priv->addr.y) < 0)
+ break;
+ } else {
+ break;
+ }
+ }
+
+ charlcd_gotoxy(lcd);
+ processed = 1;
+ break;
+ }
+
+ /* TODO: This indent party here got ugly, clean it! */
+ /* Check whether one flag was changed */
+ if (oldflags == priv->flags)
+ return processed;
+
+ /* check whether one of B,C,D flags were changed */
+ if ((oldflags ^ priv->flags) &
+ (LCD_FLAG_B | LCD_FLAG_C | LCD_FLAG_D))
+ /* set display mode */
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_DISPLAY_CTRL |
+ ((priv->flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0) |
+ ((priv->flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0) |
+ ((priv->flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0));
+ /* check whether one of F,N flags was changed */
+ else if ((oldflags ^ priv->flags) & (LCD_FLAG_F | LCD_FLAG_N))
+ lcd->ops->write_cmd(lcd,
+ LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ ((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
+ /* check whether L flag was changed */
+ else if ((oldflags ^ priv->flags) & LCD_FLAG_L)
+ charlcd_backlight(lcd, !!(priv->flags & LCD_FLAG_L));
+
+ return processed;
+}
+
+static void charlcd_write_char(struct charlcd *lcd, char c)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ /* first, we'll test if we're in escape mode */
+ if ((c != '\n') && priv->esc_seq.len >= 0) {
+ /* yes, let's add this char to the buffer */
+ priv->esc_seq.buf[priv->esc_seq.len++] = c;
+ priv->esc_seq.buf[priv->esc_seq.len] = 0;
+ } else {
+ /* aborts any previous escape sequence */
+ priv->esc_seq.len = -1;
+
+ switch (c) {
+ case LCD_ESCAPE_CHAR:
+ /* start of an escape sequence */
+ priv->esc_seq.len = 0;
+ priv->esc_seq.buf[priv->esc_seq.len] = 0;
+ break;
+ case '\b':
+ /* go back one char and clear it */
+ if (priv->addr.x > 0) {
+ /*
+ * check if we're not at the
+ * end of the line
+ */
+ if (priv->addr.x < lcd->bwidth)
+ /* back one char */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ priv->addr.x--;
+ }
+ /* replace with a space */
+ lcd->ops->write_data(lcd, ' ');
+ /* back one char again */
+ lcd->ops->write_cmd(lcd, LCD_CMD_SHIFT);
+ break;
+ case '\014':
+ /* quickly clear the display */
+ charlcd_clear_fast(lcd);
+ break;
+ case '\n':
+ /*
+ * flush the remainder of the current line and
+ * go to the beginning of the next line
+ */
+ for (; priv->addr.x < lcd->bwidth; priv->addr.x++)
+ lcd->ops->write_data(lcd, ' ');
+ priv->addr.x = 0;
+ priv->addr.y = (priv->addr.y + 1) % lcd->height;
+ charlcd_gotoxy(lcd);
+ break;
+ case '\r':
+ /* go to the beginning of the same line */
+ priv->addr.x = 0;
+ charlcd_gotoxy(lcd);
+ break;
+ case '\t':
+ /* print a space instead of the tab */
+ charlcd_print(lcd, ' ');
+ break;
+ default:
+ /* simply print this char */
+ charlcd_print(lcd, c);
+ break;
+ }
+ }
+
+ /*
+ * now we'll see if we're in an escape mode and if the current
+ * escape sequence can be understood.
+ */
+ if (priv->esc_seq.len >= 2) {
+ int processed = 0;
+
+ if (!strcmp(priv->esc_seq.buf, "[2J")) {
+ /* clear the display */
+ charlcd_clear_fast(lcd);
+ processed = 1;
+ } else if (!strcmp(priv->esc_seq.buf, "[H")) {
+ /* cursor to home */
+ charlcd_home(lcd);
+ processed = 1;
+ }
+ /* codes starting with ^[[L */
+ else if ((priv->esc_seq.len >= 3) &&
+ (priv->esc_seq.buf[0] == '[') &&
+ (priv->esc_seq.buf[1] == 'L')) {
+ processed = handle_lcd_special_code(lcd);
+ }
+
+ /* LCD special escape codes */
+ /*
+ * flush the escape sequence if it's been processed
+ * or if it is getting too long.
+ */
+ if (processed || (priv->esc_seq.len >= LCD_ESCAPE_LEN))
+ priv->esc_seq.len = -1;
+ } /* escape codes */
+}
+
+static struct charlcd *the_charlcd;
+
+static ssize_t charlcd_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ const char __user *tmp = buf;
+ char c;
+
+ for (; count-- > 0; (*ppos)++, tmp++) {
+ if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
+ /*
+ * let's be a little nice with other processes
+ * that need some CPU
+ */
+ schedule();
+
+ if (get_user(c, tmp))
+ return -EFAULT;
+
+ charlcd_write_char(the_charlcd, c);
+ }
+
+ return tmp - buf;
+}
+
+static int charlcd_open(struct inode *inode, struct file *file)
+{
+ struct charlcd_priv *priv = to_priv(the_charlcd);
+
+ if (!atomic_dec_and_test(&charlcd_available))
+ return -EBUSY; /* open only once at a time */
+
+ if (file->f_mode & FMODE_READ) /* device is write-only */
+ return -EPERM;
+
+ if (priv->must_clear) {
+ charlcd_clear_display(&priv->lcd);
+ priv->must_clear = false;
+ }
+ return nonseekable_open(inode, file);
+}
+
+static int charlcd_release(struct inode *inode, struct file *file)
+{
+ atomic_inc(&charlcd_available);
+ return 0;
+}
+
+static const struct file_operations charlcd_fops = {
+ .write = charlcd_write,
+ .open = charlcd_open,
+ .release = charlcd_release,
+ .llseek = no_llseek,
+};
+
+static struct miscdevice charlcd_dev = {
+ .minor = LCD_MINOR,
+ .name = "lcd",
+ .fops = &charlcd_fops,
+};
+
+static void charlcd_puts(struct charlcd *lcd, const char *s)
+{
+ const char *tmp = s;
+ int count = strlen(s);
+
+ for (; count-- > 0; tmp++) {
+ if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
+ /*
+ * let's be a little nice with other processes
+ * that need some CPU
+ */
+ schedule();
+
+ charlcd_write_char(lcd, *tmp);
+ }
+}
+
+/* initialize the LCD driver */
+static int charlcd_init(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+ int ret;
+
+ if (lcd->ops->backlight) {
+ mutex_init(&priv->bl_tempo_lock);
+ INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off);
+ }
+
+ /*
+ * before this line, we must NOT send anything to the display.
+ * Since charlcd_init_display() needs to write data, we have to
+ * enable mark the LCD initialized just before.
+ */
+ ret = charlcd_init_display(lcd);
+ if (ret)
+ return ret;
+
+ /* display a short message */
+#ifdef CONFIG_PANEL_CHANGE_MESSAGE
+#ifdef CONFIG_PANEL_BOOT_MESSAGE
+ charlcd_puts(lcd, "\x1b[Lc\x1b[Lb\x1b[L*" CONFIG_PANEL_BOOT_MESSAGE);
+#endif
+#else
+ charlcd_puts(lcd, "\x1b[Lc\x1b[Lb\x1b[L*Linux-" UTS_RELEASE "\n");
+#endif
+ /* clear the display on the next device opening */
+ priv->must_clear = true;
+ charlcd_home(lcd);
+ return 0;
+}
+
+struct charlcd *charlcd_alloc(unsigned int drvdata_size)
+{
+ struct charlcd_priv *priv;
+ struct charlcd *lcd;
+
+ priv = kzalloc(sizeof(*priv) + drvdata_size, GFP_KERNEL);
+ if (!priv)
+ return NULL;
+
+ priv->esc_seq.len = -1;
+
+ lcd = &priv->lcd;
+ lcd->bwidth = DEFAULT_LCD_BWIDTH;
+ lcd->hwidth = DEFAULT_LCD_HWIDTH;
+ lcd->drvdata = priv->drvdata;
+
+ return lcd;
+}
+EXPORT_SYMBOL_GPL(charlcd_alloc);
+
+static int panel_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ struct charlcd *lcd = the_charlcd;
+
+ switch (code) {
+ case SYS_DOWN:
+ charlcd_puts(lcd,
+ "\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ case SYS_HALT:
+ charlcd_puts(lcd, "\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ case SYS_POWER_OFF:
+ charlcd_puts(lcd, "\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block panel_notifier = {
+ panel_notify_sys,
+ NULL,
+ 0
+};
+
+int charlcd_register(struct charlcd *lcd)
+{
+ int ret;
+
+ ret = charlcd_init(lcd);
+ if (ret)
+ return ret;
+
+ ret = misc_register(&charlcd_dev);
+ if (ret)
+ return ret;
+
+ the_charlcd = lcd;
+ register_reboot_notifier(&panel_notifier);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_register);
+
+int charlcd_unregister(struct charlcd *lcd)
+{
+ struct charlcd_priv *priv = to_priv(lcd);
+
+ unregister_reboot_notifier(&panel_notifier);
+ charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
+ misc_deregister(&charlcd_dev);
+ the_charlcd = NULL;
+ if (lcd->ops->backlight) {
+ cancel_delayed_work_sync(&priv->bl_work);
+ priv->lcd.ops->backlight(&priv->lcd, 0);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_unregister);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index c290990d73edf87e..6e7bf55a542ebf8c 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -495,6 +495,7 @@ config VEXPRESS_SYSCFG
config PANEL
tristate "Parallel port LCD/Keypad Panel support"
depends on PARPORT
+ select CHARLCD
---help---
Say Y here if you have an HD44780 or KS-0074 LCD connected to your
parallel port. This driver also features 4 and 6-key keypads. The LCD
diff --git a/drivers/misc/panel.c b/drivers/misc/panel.c
index ef2ece0f26afc6b5..e0c014c2356ffb14 100644
--- a/drivers/misc/panel.c
+++ b/drivers/misc/panel.c
@@ -1,6 +1,7 @@
/*
* Front panel driver for Linux
* Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -54,15 +55,12 @@
#include <linux/ctype.h>
#include <linux/parport.h>
#include <linux/list.h>
-#include <linux/notifier.h>
-#include <linux/reboot.h>
-#include <linux/workqueue.h>
-#include <generated/utsrelease.h>
#include <linux/io.h>
#include <linux/uaccess.h>
-#define LCD_MINOR 156
+#include <misc/charlcd.h>
+
#define KEYPAD_MINOR 185
#define LCD_MAXBYTES 256 /* max burst write */
@@ -76,9 +74,6 @@
/* a key repeats this times INPUT_POLL_TIME */
#define KEYPAD_REP_DELAY (2)
-/* keep the light on this many seconds for each flash */
-#define FLASH_LIGHT_TEMPO (4)
-
/* converts an r_str() input to an active high, bits string : 000BAOSE */
#define PNL_PINPUT(a) ((((unsigned char)(a)) ^ 0x7F) >> 3)
@@ -120,40 +115,6 @@
#define PIN_SELECP 17
#define PIN_NOT_SET 127
-#define LCD_FLAG_B 0x0004 /* blink on */
-#define LCD_FLAG_C 0x0008 /* cursor on */
-#define LCD_FLAG_D 0x0010 /* display on */
-#define LCD_FLAG_F 0x0020 /* large font mode */
-#define LCD_FLAG_N 0x0040 /* 2-rows mode */
-#define LCD_FLAG_L 0x0080 /* backlight enabled */
-
-/* LCD commands */
-#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
-
-#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
-#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
-
-#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
-#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
-#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
-#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
-
-#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
-#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
-#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
-
-#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
-#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
-#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
-#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
-
-#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
-
-#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
-
-#define LCD_ESCAPE_LEN 24 /* max chars for LCD escape command */
-#define LCD_ESCAPE_CHAR 27 /* use char 27 for escape command */
-
#define NOT_SET -1
/* macros to simplify use of the parallel port */
@@ -245,19 +206,10 @@ static wait_queue_head_t keypad_read_wait;
static struct {
bool enabled;
bool initialized;
- bool must_clear;
- int height;
- int width;
- int bwidth;
- int hwidth;
int charset;
int proto;
- struct delayed_work bl_work;
- struct mutex bl_tempo_lock; /* Protects access to bl_tempo */
- bool bl_tempo;
-
/* TODO: use union here? */
struct {
int e;
@@ -268,20 +220,7 @@ static struct {
int bl;
} pins;
- /* contains the LCD config state */
- unsigned long int flags;
-
- /* Contains the LCD X and Y offset */
- struct {
- unsigned long int x;
- unsigned long int y;
- } addr;
-
- /* Current escape sequence and it's length or -1 if outside */
- struct {
- char buf[LCD_ESCAPE_LEN + 1];
- int len;
- } esc_seq;
+ struct charlcd *charlcd;
} lcd;
/* Needed only for init */
@@ -464,17 +403,12 @@ static unsigned char lcd_bits[LCD_PORTS][LCD_BITS][BIT_STATES];
/* global variables */
/* Device single-open policy control */
-static atomic_t lcd_available = ATOMIC_INIT(1);
static atomic_t keypad_available = ATOMIC_INIT(1);
static struct pardevice *pprt;
static int keypad_initialized;
-static void (*lcd_write_cmd)(int);
-static void (*lcd_write_data)(int);
-static void (*lcd_clear_fast)(void);
-
static DEFINE_SPINLOCK(pprt_lock);
static struct timer_list scan_timer;
@@ -574,8 +508,6 @@ static int keypad_enabled = NOT_SET;
module_param(keypad_enabled, int, 0000);
MODULE_PARM_DESC(keypad_enabled, "Deprecated option, use keypad_type instead");
-static const unsigned char *lcd_char_conv;
-
/* for some LCD drivers (ks0074) we need a charset conversion table. */
static const unsigned char lcd_char_conv_ks0074[256] = {
/* 0|8 1|9 2|A 3|B 4|C 5|D 6|E 7|F */
@@ -752,15 +684,6 @@ static void pin_to_bits(int pin, unsigned char *d_val, unsigned char *c_val)
}
}
-/* sleeps that many milliseconds with a reschedule */
-static void long_sleep(int ms)
-{
- if (in_interrupt())
- mdelay(ms);
- else
- schedule_timeout_interruptible(msecs_to_jiffies(ms));
-}
-
/*
* send a serial byte to the LCD panel. The caller is responsible for locking
* if needed.
@@ -792,8 +715,11 @@ static void lcd_send_serial(int byte)
}
/* turn the backlight on or off */
-static void __lcd_backlight(int on)
+static void lcd_backlight(struct charlcd *charlcd, int on)
{
+ if (lcd.pins.bl == PIN_NONE)
+ return;
+
/* The backlight is activated by setting the AUTOFEED line to +5V */
spin_lock_irq(&pprt_lock);
if (on)
@@ -804,46 +730,8 @@ static void __lcd_backlight(int on)
spin_unlock_irq(&pprt_lock);
}
-static void lcd_backlight(int on)
-{
- if (lcd.pins.bl == PIN_NONE)
- return;
-
- mutex_lock(&lcd.bl_tempo_lock);
- if (!lcd.bl_tempo)
- __lcd_backlight(on);
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
-static void lcd_bl_off(struct work_struct *work)
-{
- mutex_lock(&lcd.bl_tempo_lock);
- if (lcd.bl_tempo) {
- lcd.bl_tempo = false;
- if (!(lcd.flags & LCD_FLAG_L))
- __lcd_backlight(0);
- }
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
-/* turn the backlight on for a little while */
-static void lcd_poke(void)
-{
- if (lcd.pins.bl == PIN_NONE)
- return;
-
- cancel_delayed_work_sync(&lcd.bl_work);
-
- mutex_lock(&lcd.bl_tempo_lock);
- if (!lcd.bl_tempo && !(lcd.flags & LCD_FLAG_L))
- __lcd_backlight(1);
- lcd.bl_tempo = true;
- schedule_delayed_work(&lcd.bl_work, FLASH_LIGHT_TEMPO * HZ);
- mutex_unlock(&lcd.bl_tempo_lock);
-}
-
/* send a command to the LCD panel in serial mode */
-static void lcd_write_cmd_s(int cmd)
+static void lcd_write_cmd_s(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
lcd_send_serial(0x1F); /* R/W=W, RS=0 */
@@ -854,7 +742,7 @@ static void lcd_write_cmd_s(int cmd)
}
/* send data to the LCD panel in serial mode */
-static void lcd_write_data_s(int data)
+static void lcd_write_data_s(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
lcd_send_serial(0x5F); /* R/W=W, RS=1 */
@@ -865,7 +753,7 @@ static void lcd_write_data_s(int data)
}
/* send a command to the LCD panel in 8 bits parallel mode */
-static void lcd_write_cmd_p8(int cmd)
+static void lcd_write_cmd_p8(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -887,7 +775,7 @@ static void lcd_write_cmd_p8(int cmd)
}
/* send data to the LCD panel in 8 bits parallel mode */
-static void lcd_write_data_p8(int data)
+static void lcd_write_data_p8(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -909,7 +797,7 @@ static void lcd_write_data_p8(int data)
}
/* send a command to the TI LCD panel */
-static void lcd_write_cmd_tilcd(int cmd)
+static void lcd_write_cmd_tilcd(struct charlcd *charlcd, int cmd)
{
spin_lock_irq(&pprt_lock);
/* present the data to the control port */
@@ -919,7 +807,7 @@ static void lcd_write_cmd_tilcd(int cmd)
}
/* send data to the TI LCD panel */
-static void lcd_write_data_tilcd(int data)
+static void lcd_write_data_tilcd(struct charlcd *charlcd, int data)
{
spin_lock_irq(&pprt_lock);
/* present the data to the data port */
@@ -928,47 +816,13 @@ static void lcd_write_data_tilcd(int data)
spin_unlock_irq(&pprt_lock);
}
-static void lcd_gotoxy(void)
-{
- lcd_write_cmd(LCD_CMD_SET_DDRAM_ADDR
- | (lcd.addr.y ? lcd.hwidth : 0)
- /*
- * we force the cursor to stay at the end of the
- * line if it wants to go farther
- */
- | ((lcd.addr.x < lcd.bwidth) ? lcd.addr.x &
- (lcd.hwidth - 1) : lcd.bwidth - 1));
-}
-
-static void lcd_home(void)
-{
- lcd.addr.x = 0;
- lcd.addr.y = 0;
- lcd_gotoxy();
-}
-
-static void lcd_print(char c)
-{
- if (lcd.addr.x < lcd.bwidth) {
- if (lcd_char_conv)
- c = lcd_char_conv[(unsigned char)c];
- lcd_write_data(c);
- lcd.addr.x++;
- }
- /* prevents the cursor from wrapping onto the next line */
- if (lcd.addr.x == lcd.bwidth)
- lcd_gotoxy();
-}
-
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_s(void)
+static void lcd_clear_fast_s(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
lcd_send_serial(0x5F); /* R/W=W, RS=1 */
lcd_send_serial(' ' & 0x0F);
lcd_send_serial((' ' >> 4) & 0x0F);
@@ -976,19 +830,15 @@ static void lcd_clear_fast_s(void)
udelay(40);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
}
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_p8(void)
+static void lcd_clear_fast_p8(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
@@ -1010,488 +860,62 @@ static void lcd_clear_fast_p8(void)
udelay(45);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
}
/* fills the display with spaces and resets X/Y */
-static void lcd_clear_fast_tilcd(void)
+static void lcd_clear_fast_tilcd(struct charlcd *charlcd)
{
int pos;
- lcd_home();
-
spin_lock_irq(&pprt_lock);
- for (pos = 0; pos < lcd.height * lcd.hwidth; pos++) {
+ for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
udelay(60);
}
spin_unlock_irq(&pprt_lock);
-
- lcd_home();
-}
-
-/* clears the display and resets X/Y */
-static void lcd_clear_display(void)
-{
- lcd_write_cmd(LCD_CMD_DISPLAY_CLEAR);
- lcd.addr.x = 0;
- lcd.addr.y = 0;
- /* we must wait a few milliseconds (15) */
- long_sleep(15);
}
-static void lcd_init_display(void)
-{
- lcd.flags = ((lcd.height > 1) ? LCD_FLAG_N : 0)
- | LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
-
- long_sleep(20); /* wait 20 ms after power-up for the paranoid */
-
- /* 8bits, 1 line, small fonts; let's do it 3 times */
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
- long_sleep(10);
-
- /* set font height and lines number */
- lcd_write_cmd(LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS
- | ((lcd.flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0)
- | ((lcd.flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0)
- );
- long_sleep(10);
-
- /* display off, cursor off, blink off */
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL);
- long_sleep(10);
-
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL /* set display mode */
- | ((lcd.flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0)
- | ((lcd.flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0)
- | ((lcd.flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0)
- );
-
- lcd_backlight((lcd.flags & LCD_FLAG_L) ? 1 : 0);
-
- long_sleep(10);
-
- /* entry mode set : increment, cursor shifting */
- lcd_write_cmd(LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+static struct charlcd_ops charlcd_serial_ops = {
+ .write_cmd = lcd_write_cmd_s,
+ .write_data = lcd_write_data_s,
+ .clear_fast = lcd_clear_fast_s,
+ .backlight = lcd_backlight,
+};
- lcd_clear_display();
-}
+static struct charlcd_ops charlcd_parallel_ops = {
+ .write_cmd = lcd_write_cmd_p8,
+ .write_data = lcd_write_data_p8,
+ .clear_fast = lcd_clear_fast_p8,
+ .backlight = lcd_backlight,
+};
-/*
- * These are the file operation function for user access to /dev/lcd
- * This function can also be called from inside the kernel, by
- * setting file and ppos to NULL.
- *
- */
+static struct charlcd_ops charlcd_tilcd_ops = {
+ .write_cmd = lcd_write_cmd_tilcd,
+ .write_data = lcd_write_data_tilcd,
+ .clear_fast = lcd_clear_fast_tilcd,
+ .backlight = lcd_backlight,
+};
-static inline int handle_lcd_special_code(void)
+/* initialize the LCD driver */
+static void lcd_init(void)
{
- /* LCD special codes */
-
- int processed = 0;
+ struct charlcd *charlcd;
- char *esc = lcd.esc_seq.buf + 2;
- int oldflags = lcd.flags;
-
- /* check for display mode flags */
- switch (*esc) {
- case 'D': /* Display ON */
- lcd.flags |= LCD_FLAG_D;
- processed = 1;
- break;
- case 'd': /* Display OFF */
- lcd.flags &= ~LCD_FLAG_D;
- processed = 1;
- break;
- case 'C': /* Cursor ON */
- lcd.flags |= LCD_FLAG_C;
- processed = 1;
- break;
- case 'c': /* Cursor OFF */
- lcd.flags &= ~LCD_FLAG_C;
- processed = 1;
- break;
- case 'B': /* Blink ON */
- lcd.flags |= LCD_FLAG_B;
- processed = 1;
- break;
- case 'b': /* Blink OFF */
- lcd.flags &= ~LCD_FLAG_B;
- processed = 1;
- break;
- case '+': /* Back light ON */
- lcd.flags |= LCD_FLAG_L;
- processed = 1;
- break;
- case '-': /* Back light OFF */
- lcd.flags &= ~LCD_FLAG_L;
- processed = 1;
- break;
- case '*':
- /* flash back light */
- lcd_poke();
- processed = 1;
- break;
- case 'f': /* Small Font */
- lcd.flags &= ~LCD_FLAG_F;
- processed = 1;
- break;
- case 'F': /* Large Font */
- lcd.flags |= LCD_FLAG_F;
- processed = 1;
- break;
- case 'n': /* One Line */
- lcd.flags &= ~LCD_FLAG_N;
- processed = 1;
- break;
- case 'N': /* Two Lines */
- lcd.flags |= LCD_FLAG_N;
- break;
- case 'l': /* Shift Cursor Left */
- if (lcd.addr.x > 0) {
- /* back one char if not at end of line */
- if (lcd.addr.x < lcd.bwidth)
- lcd_write_cmd(LCD_CMD_SHIFT);
- lcd.addr.x--;
- }
- processed = 1;
- break;
- case 'r': /* shift cursor right */
- if (lcd.addr.x < lcd.width) {
- /* allow the cursor to pass the end of the line */
- if (lcd.addr.x < (lcd.bwidth - 1))
- lcd_write_cmd(LCD_CMD_SHIFT |
- LCD_CMD_SHIFT_RIGHT);
- lcd.addr.x++;
- }
- processed = 1;
- break;
- case 'L': /* shift display left */
- lcd_write_cmd(LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
- processed = 1;
- break;
- case 'R': /* shift display right */
- lcd_write_cmd(LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
- LCD_CMD_SHIFT_RIGHT);
- processed = 1;
- break;
- case 'k': { /* kill end of line */
- int x;
-
- for (x = lcd.addr.x; x < lcd.bwidth; x++)
- lcd_write_data(' ');
-
- /* restore cursor position */
- lcd_gotoxy();
- processed = 1;
- break;
- }
- case 'I': /* reinitialize display */
- lcd_init_display();
- processed = 1;
- break;
- case 'G': {
- /* Generator : LGcxxxxx...xx; must have <c> between '0'
- * and '7', representing the numerical ASCII code of the
- * redefined character, and <xx...xx> a sequence of 16
- * hex digits representing 8 bytes for each character.
- * Most LCDs will only use 5 lower bits of the 7 first
- * bytes.
- */
-
- unsigned char cgbytes[8];
- unsigned char cgaddr;
- int cgoffset;
- int shift;
- char value;
- int addr;
-
- if (!strchr(esc, ';'))
- break;
-
- esc++;
-
- cgaddr = *(esc++) - '0';
- if (cgaddr > 7) {
- processed = 1;
- break;
- }
-
- cgoffset = 0;
- shift = 0;
- value = 0;
- while (*esc && cgoffset < 8) {
- shift ^= 4;
- if (*esc >= '0' && *esc <= '9') {
- value |= (*esc - '0') << shift;
- } else if (*esc >= 'A' && *esc <= 'Z') {
- value |= (*esc - 'A' + 10) << shift;
- } else if (*esc >= 'a' && *esc <= 'z') {
- value |= (*esc - 'a' + 10) << shift;
- } else {
- esc++;
- continue;
- }
-
- if (shift == 0) {
- cgbytes[cgoffset++] = value;
- value = 0;
- }
-
- esc++;
- }
-
- lcd_write_cmd(LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
- for (addr = 0; addr < cgoffset; addr++)
- lcd_write_data(cgbytes[addr]);
-
- /* ensures that we stop writing to CGRAM */
- lcd_gotoxy();
- processed = 1;
- break;
- }
- case 'x': /* gotoxy : LxXXX[yYYY]; */
- case 'y': /* gotoxy : LyYYY[xXXX]; */
- if (!strchr(esc, ';'))
- break;
-
- while (*esc) {
- if (*esc == 'x') {
- esc++;
- if (kstrtoul(esc, 10, &lcd.addr.x) < 0)
- break;
- } else if (*esc == 'y') {
- esc++;
- if (kstrtoul(esc, 10, &lcd.addr.y) < 0)
- break;
- } else {
- break;
- }
- }
-
- lcd_gotoxy();
- processed = 1;
- break;
- }
-
- /* TODO: This indent party here got ugly, clean it! */
- /* Check whether one flag was changed */
- if (oldflags != lcd.flags) {
- /* check whether one of B,C,D flags were changed */
- if ((oldflags ^ lcd.flags) &
- (LCD_FLAG_B | LCD_FLAG_C | LCD_FLAG_D))
- /* set display mode */
- lcd_write_cmd(LCD_CMD_DISPLAY_CTRL
- | ((lcd.flags & LCD_FLAG_D)
- ? LCD_CMD_DISPLAY_ON : 0)
- | ((lcd.flags & LCD_FLAG_C)
- ? LCD_CMD_CURSOR_ON : 0)
- | ((lcd.flags & LCD_FLAG_B)
- ? LCD_CMD_BLINK_ON : 0));
- /* check whether one of F,N flags was changed */
- else if ((oldflags ^ lcd.flags) & (LCD_FLAG_F | LCD_FLAG_N))
- lcd_write_cmd(LCD_CMD_FUNCTION_SET
- | LCD_CMD_DATA_LEN_8BITS
- | ((lcd.flags & LCD_FLAG_F)
- ? LCD_CMD_FONT_5X10_DOTS
- : 0)
- | ((lcd.flags & LCD_FLAG_N)
- ? LCD_CMD_TWO_LINES
- : 0));
- /* check whether L flag was changed */
- else if ((oldflags ^ lcd.flags) & (LCD_FLAG_L))
- lcd_backlight(!!(lcd.flags & LCD_FLAG_L));
- }
-
- return processed;
-}
-
-static void lcd_write_char(char c)
-{
- /* first, we'll test if we're in escape mode */
- if ((c != '\n') && lcd.esc_seq.len >= 0) {
- /* yes, let's add this char to the buffer */
- lcd.esc_seq.buf[lcd.esc_seq.len++] = c;
- lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
- } else {
- /* aborts any previous escape sequence */
- lcd.esc_seq.len = -1;
-
- switch (c) {
- case LCD_ESCAPE_CHAR:
- /* start of an escape sequence */
- lcd.esc_seq.len = 0;
- lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
- break;
- case '\b':
- /* go back one char and clear it */
- if (lcd.addr.x > 0) {
- /*
- * check if we're not at the
- * end of the line
- */
- if (lcd.addr.x < lcd.bwidth)
- /* back one char */
- lcd_write_cmd(LCD_CMD_SHIFT);
- lcd.addr.x--;
- }
- /* replace with a space */
- lcd_write_data(' ');
- /* back one char again */
- lcd_write_cmd(LCD_CMD_SHIFT);
- break;
- case '\014':
- /* quickly clear the display */
- lcd_clear_fast();
- break;
- case '\n':
- /*
- * flush the remainder of the current line and
- * go to the beginning of the next line
- */
- for (; lcd.addr.x < lcd.bwidth; lcd.addr.x++)
- lcd_write_data(' ');
- lcd.addr.x = 0;
- lcd.addr.y = (lcd.addr.y + 1) % lcd.height;
- lcd_gotoxy();
- break;
- case '\r':
- /* go to the beginning of the same line */
- lcd.addr.x = 0;
- lcd_gotoxy();
- break;
- case '\t':
- /* print a space instead of the tab */
- lcd_print(' ');
- break;
- default:
- /* simply print this char */
- lcd_print(c);
- break;
- }
- }
+ charlcd = charlcd_alloc(0);
+ if (!charlcd)
+ return;
/*
- * now we'll see if we're in an escape mode and if the current
- * escape sequence can be understood.
+ * Init lcd struct with load-time values to preserve exact
+ * current functionality (at least for now).
*/
- if (lcd.esc_seq.len >= 2) {
- int processed = 0;
-
- if (!strcmp(lcd.esc_seq.buf, "[2J")) {
- /* clear the display */
- lcd_clear_fast();
- processed = 1;
- } else if (!strcmp(lcd.esc_seq.buf, "[H")) {
- /* cursor to home */
- lcd_home();
- processed = 1;
- }
- /* codes starting with ^[[L */
- else if ((lcd.esc_seq.len >= 3) &&
- (lcd.esc_seq.buf[0] == '[') &&
- (lcd.esc_seq.buf[1] == 'L')) {
- processed = handle_lcd_special_code();
- }
-
- /* LCD special escape codes */
- /*
- * flush the escape sequence if it's been processed
- * or if it is getting too long.
- */
- if (processed || (lcd.esc_seq.len >= LCD_ESCAPE_LEN))
- lcd.esc_seq.len = -1;
- } /* escape codes */
-}
+ charlcd->height = lcd_height;
+ charlcd->width = lcd_width;
+ charlcd->bwidth = lcd_bwidth;
+ charlcd->hwidth = lcd_hwidth;
-static ssize_t lcd_write(struct file *file,
- const char __user *buf, size_t count, loff_t *ppos)
-{
- const char __user *tmp = buf;
- char c;
-
- for (; count-- > 0; (*ppos)++, tmp++) {
- if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
- /*
- * let's be a little nice with other processes
- * that need some CPU
- */
- schedule();
-
- if (get_user(c, tmp))
- return -EFAULT;
-
- lcd_write_char(c);
- }
-
- return tmp - buf;
-}
-
-static int lcd_open(struct inode *inode, struct file *file)
-{
- if (!atomic_dec_and_test(&lcd_available))
- return -EBUSY; /* open only once at a time */
-
- if (file->f_mode & FMODE_READ) /* device is write-only */
- return -EPERM;
-
- if (lcd.must_clear) {
- lcd_clear_display();
- lcd.must_clear = false;
- }
- return nonseekable_open(inode, file);
-}
-
-static int lcd_release(struct inode *inode, struct file *file)
-{
- atomic_inc(&lcd_available);
- return 0;
-}
-
-static const struct file_operations lcd_fops = {
- .write = lcd_write,
- .open = lcd_open,
- .release = lcd_release,
- .llseek = no_llseek,
-};
-
-static struct miscdevice lcd_dev = {
- .minor = LCD_MINOR,
- .name = "lcd",
- .fops = &lcd_fops,
-};
-
-/* public function usable from the kernel for any purpose */
-static void panel_lcd_print(const char *s)
-{
- const char *tmp = s;
- int count = strlen(s);
-
- if (lcd.enabled && lcd.initialized) {
- for (; count-- > 0; tmp++) {
- if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
- /*
- * let's be a little nice with other processes
- * that need some CPU
- */
- schedule();
-
- lcd_write_char(*tmp);
- }
- }
-}
-
-/* initialize the LCD driver */
-static void lcd_init(void)
-{
switch (selected_lcd_type) {
case LCD_TYPE_OLD:
/* parallel mode, 8 bits */
@@ -1500,10 +924,10 @@ static void lcd_init(void)
lcd.pins.e = PIN_STROBE;
lcd.pins.rs = PIN_AUTOLF;
- lcd.width = 40;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 40;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
case LCD_TYPE_KS0074:
/* serial mode, ks0074 */
@@ -1513,10 +937,10 @@ static void lcd_init(void)
lcd.pins.cl = PIN_STROBE;
lcd.pins.da = PIN_D0;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 16;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 16;
+ charlcd->height = 2;
break;
case LCD_TYPE_NEXCOM:
/* parallel mode, 8 bits, generic */
@@ -1526,10 +950,10 @@ static void lcd_init(void)
lcd.pins.rs = PIN_SELECP;
lcd.pins.rw = PIN_INITP;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
case LCD_TYPE_CUSTOM:
/* customer-defined */
@@ -1545,22 +969,22 @@ static void lcd_init(void)
lcd.pins.e = PIN_STROBE;
lcd.pins.rs = PIN_SELECP;
- lcd.width = 16;
- lcd.bwidth = 40;
- lcd.hwidth = 64;
- lcd.height = 2;
+ charlcd->width = 16;
+ charlcd->bwidth = 40;
+ charlcd->hwidth = 64;
+ charlcd->height = 2;
break;
}
/* Overwrite with module params set on loading */
if (lcd_height != NOT_SET)
- lcd.height = lcd_height;
+ charlcd->height = lcd_height;
if (lcd_width != NOT_SET)
- lcd.width = lcd_width;
+ charlcd->width = lcd_width;
if (lcd_bwidth != NOT_SET)
- lcd.bwidth = lcd_bwidth;
+ charlcd->bwidth = lcd_bwidth;
if (lcd_hwidth != NOT_SET)
- lcd.hwidth = lcd_hwidth;
+ charlcd->hwidth = lcd_hwidth;
if (lcd_charset != NOT_SET)
lcd.charset = lcd_charset;
if (lcd_proto != NOT_SET)
@@ -1579,19 +1003,17 @@ static void lcd_init(void)
lcd.pins.bl = lcd_bl_pin;
/* this is used to catch wrong and default values */
- if (lcd.width <= 0)
- lcd.width = DEFAULT_LCD_WIDTH;
- if (lcd.bwidth <= 0)
- lcd.bwidth = DEFAULT_LCD_BWIDTH;
- if (lcd.hwidth <= 0)
- lcd.hwidth = DEFAULT_LCD_HWIDTH;
- if (lcd.height <= 0)
- lcd.height = DEFAULT_LCD_HEIGHT;
+ if (charlcd->width <= 0)
+ charlcd->width = DEFAULT_LCD_WIDTH;
+ if (charlcd->bwidth <= 0)
+ charlcd->bwidth = DEFAULT_LCD_BWIDTH;
+ if (charlcd->hwidth <= 0)
+ charlcd->hwidth = DEFAULT_LCD_HWIDTH;
+ if (charlcd->height <= 0)
+ charlcd->height = DEFAULT_LCD_HEIGHT;
if (lcd.proto == LCD_PROTO_SERIAL) { /* SERIAL */
- lcd_write_cmd = lcd_write_cmd_s;
- lcd_write_data = lcd_write_data_s;
- lcd_clear_fast = lcd_clear_fast_s;
+ charlcd->ops = &charlcd_serial_ops;
if (lcd.pins.cl == PIN_NOT_SET)
lcd.pins.cl = DEFAULT_LCD_PIN_SCL;
@@ -1599,9 +1021,7 @@ static void lcd_init(void)
lcd.pins.da = DEFAULT_LCD_PIN_SDA;
} else if (lcd.proto == LCD_PROTO_PARALLEL) { /* PARALLEL */
- lcd_write_cmd = lcd_write_cmd_p8;
- lcd_write_data = lcd_write_data_p8;
- lcd_clear_fast = lcd_clear_fast_p8;
+ charlcd->ops = &charlcd_parallel_ops;
if (lcd.pins.e == PIN_NOT_SET)
lcd.pins.e = DEFAULT_LCD_PIN_E;
@@ -1610,9 +1030,7 @@ static void lcd_init(void)
if (lcd.pins.rw == PIN_NOT_SET)
lcd.pins.rw = DEFAULT_LCD_PIN_RW;
} else {
- lcd_write_cmd = lcd_write_cmd_tilcd;
- lcd_write_data = lcd_write_data_tilcd;
- lcd_clear_fast = lcd_clear_fast_tilcd;
+ charlcd->ops = &charlcd_tilcd_ops;
}
if (lcd.pins.bl == PIN_NOT_SET)
@@ -1635,14 +1053,9 @@ static void lcd_init(void)
lcd.charset = DEFAULT_LCD_CHARSET;
if (lcd.charset == LCD_CHARSET_KS0074)
- lcd_char_conv = lcd_char_conv_ks0074;
+ charlcd->char_conv = lcd_char_conv_ks0074;
else
- lcd_char_conv = NULL;
-
- if (lcd.pins.bl != PIN_NONE) {
- mutex_init(&lcd.bl_tempo_lock);
- INIT_DELAYED_WORK(&lcd.bl_work, lcd_bl_off);
- }
+ charlcd->char_conv = NULL;
pin_to_bits(lcd.pins.e, lcd_bits[LCD_PORT_D][LCD_BIT_E],
lcd_bits[LCD_PORT_C][LCD_BIT_E]);
@@ -1657,25 +1070,8 @@ static void lcd_init(void)
pin_to_bits(lcd.pins.da, lcd_bits[LCD_PORT_D][LCD_BIT_DA],
lcd_bits[LCD_PORT_C][LCD_BIT_DA]);
- /*
- * before this line, we must NOT send anything to the display.
- * Since lcd_init_display() needs to write data, we have to
- * enable mark the LCD initialized just before.
- */
+ lcd.charlcd = charlcd;
lcd.initialized = true;
- lcd_init_display();
-
- /* display a short message */
-#ifdef CONFIG_PANEL_CHANGE_MESSAGE
-#ifdef CONFIG_PANEL_BOOT_MESSAGE
- panel_lcd_print("\x1b[Lc\x1b[Lb\x1b[L*" CONFIG_PANEL_BOOT_MESSAGE);
-#endif
-#else
- panel_lcd_print("\x1b[Lc\x1b[Lb\x1b[L*Linux-" UTS_RELEASE);
-#endif
- /* clear the display on the next device opening */
- lcd.must_clear = true;
- lcd_home();
}
/*
@@ -2011,7 +1407,7 @@ static void panel_scan_timer(void)
}
if (keypressed && lcd.enabled && lcd.initialized)
- lcd_poke();
+ charlcd_poke(lcd.charlcd);
mod_timer(&scan_timer, jiffies + INPUT_POLL_TIME);
}
@@ -2175,35 +1571,6 @@ static void keypad_init(void)
/* device initialization */
/**************************************************/
-static int panel_notify_sys(struct notifier_block *this, unsigned long code,
- void *unused)
-{
- if (lcd.enabled && lcd.initialized) {
- switch (code) {
- case SYS_DOWN:
- panel_lcd_print
- ("\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- case SYS_HALT:
- panel_lcd_print
- ("\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- case SYS_POWER_OFF:
- panel_lcd_print("\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
- break;
- default:
- break;
- }
- }
- return NOTIFY_DONE;
-}
-
-static struct notifier_block panel_notifier = {
- panel_notify_sys,
- NULL,
- 0
-};
-
static void panel_attach(struct parport *port)
{
struct pardev_cb panel_cb;
@@ -2239,7 +1606,7 @@ static void panel_attach(struct parport *port)
*/
if (lcd.enabled) {
lcd_init();
- if (misc_register(&lcd_dev))
+ if (!lcd.charlcd || charlcd_register(lcd.charlcd))
goto err_unreg_device;
}
@@ -2248,13 +1615,14 @@ static void panel_attach(struct parport *port)
if (misc_register(&keypad_dev))
goto err_lcd_unreg;
}
- register_reboot_notifier(&panel_notifier);
return;
err_lcd_unreg:
if (lcd.enabled)
- misc_deregister(&lcd_dev);
+ charlcd_unregister(lcd.charlcd);
err_unreg_device:
+ kfree(lcd.charlcd);
+ lcd.charlcd = NULL;
parport_unregister_device(pprt);
pprt = NULL;
}
@@ -2278,20 +1646,16 @@ static void panel_detach(struct parport *port)
}
if (lcd.enabled) {
- panel_lcd_print("\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
- misc_deregister(&lcd_dev);
- if (lcd.pins.bl != PIN_NONE) {
- cancel_delayed_work_sync(&lcd.bl_work);
- __lcd_backlight(0);
- }
+ charlcd_unregister(lcd.charlcd);
lcd.initialized = false;
+ kfree(lcd.charlcd);
+ lcd.charlcd = NULL;
}
/* TODO: free all input signals */
parport_release(pprt);
parport_unregister_device(pprt);
pprt = NULL;
- unregister_reboot_notifier(&panel_notifier);
}
static struct parport_driver panel_driver = {
@@ -2369,10 +1733,6 @@ static int __init panel_init_module(void)
* Init lcd struct with load-time values to preserve exact
* current functionality (at least for now).
*/
- lcd.height = lcd_height;
- lcd.width = lcd_width;
- lcd.bwidth = lcd_bwidth;
- lcd.hwidth = lcd_hwidth;
lcd.charset = lcd_charset;
lcd.proto = lcd_proto;
lcd.pins.e = lcd_e_pin;
@@ -2381,9 +1741,6 @@ static int __init panel_init_module(void)
lcd.pins.cl = lcd_cl_pin;
lcd.pins.da = lcd_da_pin;
lcd.pins.bl = lcd_bl_pin;
-
- /* Leave it for now, just in case */
- lcd.esc_seq.len = -1;
}
switch (selected_keypad_type) {
diff --git a/include/misc/charlcd.h b/include/misc/charlcd.h
new file mode 100644
index 0000000000000000..c40047b673c9ea09
--- /dev/null
+++ b/include/misc/charlcd.h
@@ -0,0 +1,40 @@
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+struct charlcd {
+ const struct charlcd_ops *ops;
+ const unsigned char *char_conv; /* Optional */
+
+ int height;
+ int width;
+ int bwidth; /* Default set by charlcd_alloc() */
+ int hwidth; /* Default set by charlcd_alloc() */
+
+ void *drvdata; /* Set by charlcd_alloc() */
+};
+
+struct charlcd_ops {
+ /* Required */
+ void (*write_cmd)(struct charlcd *lcd, int cmd);
+ void (*write_data)(struct charlcd *lcd, int data);
+
+ /* Optional */
+ void (*clear_fast)(struct charlcd *lcd);
+ void (*backlight)(struct charlcd *lcd, int on);
+};
+
+struct charlcd *charlcd_alloc(unsigned int drvdata_size);
+
+int charlcd_register(struct charlcd *lcd);
+int charlcd_unregister(struct charlcd *lcd);
+
+void charlcd_poke(struct charlcd *lcd);
--
2.7.4
--
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^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 2/5] auxdisplay: charlcd: Add support for 4-bit interfaces
2017-03-10 14:15 ` Geert Uytterhoeven
(?)
(?)
@ 2017-03-10 14:15 ` Geert Uytterhoeven
-1 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
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>
---
v2:
- No changes.
---
drivers/auxdisplay/charlcd.c | 36 ++++++++++++++++++++++++++++++------
include/misc/charlcd.h | 2 ++
2 files changed, 32 insertions(+), 6 deletions(-)
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index 930ffb2fb31787c5..b3a84e90a268478c 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -223,24 +223,46 @@ static void charlcd_clear_display(struct charlcd *lcd)
static int charlcd_init_display(struct charlcd *lcd)
{
+ void (*write_cmd_raw)(struct charlcd *lcd, int cmd);
struct charlcd_priv *priv = to_priv(lcd);
+ u8 init;
+
+ if (lcd->ifwidth != 4 && lcd->ifwidth != 8)
+ return -EINVAL;
priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
LCD_FLAG_C | LCD_FLAG_B;
long_sleep(20); /* wait 20 ms after power-up for the paranoid */
- /* 8bits, 1 line, small fonts; let's do it 3 times */
- lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ /*
+ * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
+ * the LCD is in 8-bit mode afterwards
+ */
+ init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
+ if (lcd->ifwidth == 4) {
+ init >>= 4;
+ write_cmd_raw = lcd->ops->write_cmd_raw4;
+ } else {
+ write_cmd_raw = lcd->ops->write_cmd;
+ }
+ write_cmd_raw(lcd, init);
long_sleep(10);
- lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ write_cmd_raw(lcd, init);
long_sleep(10);
- lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS);
+ write_cmd_raw(lcd, init);
long_sleep(10);
+ if (lcd->ifwidth == 4) {
+ /* Switch to 4-bit mode, 1 line, small fonts */
+ lcd->ops->write_cmd_raw4(lcd, LCD_CMD_FUNCTION_SET >> 4);
+ long_sleep(10);
+ }
+
/* set font height and lines number */
lcd->ops->write_cmd(lcd,
- LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ LCD_CMD_FUNCTION_SET |
+ ((lcd->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
long_sleep(10);
@@ -482,7 +504,8 @@ static inline int handle_lcd_special_code(struct charlcd *lcd)
/* check whether one of F,N flags was changed */
else if ((oldflags ^ priv->flags) & (LCD_FLAG_F | LCD_FLAG_N))
lcd->ops->write_cmd(lcd,
- LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS |
+ LCD_CMD_FUNCTION_SET |
+ ((lcd->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
/* check whether L flag was changed */
@@ -716,6 +739,7 @@ struct charlcd *charlcd_alloc(unsigned int drvdata_size)
priv->esc_seq.len = -1;
lcd = &priv->lcd;
+ lcd->ifwidth = 8;
lcd->bwidth = DEFAULT_LCD_BWIDTH;
lcd->hwidth = DEFAULT_LCD_HWIDTH;
lcd->drvdata = priv->drvdata;
diff --git a/include/misc/charlcd.h b/include/misc/charlcd.h
index c40047b673c9ea09..23f61850f3639ae1 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);
};
--
2.7.4
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 3/5] auxdisplay: charlcd: Add support for displays with more than two lines
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
On displays with more than two lines, the additional lines are stored in
the buffers used for the first two lines, but beyond the visible parts.
Adjust the DDRAM address calculation to cater for this.
When clearing the display, avoid writing more spaces than the actual
size of the physical buffer.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
v2:
- No changes.
---
drivers/auxdisplay/charlcd.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index b3a84e90a268478c..cfeb049a01ef8442 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -159,15 +159,19 @@ EXPORT_SYMBOL_GPL(charlcd_poke);
static void charlcd_gotoxy(struct charlcd *lcd)
{
struct charlcd_priv *priv = to_priv(lcd);
+ unsigned int addr;
- lcd->ops->write_cmd(lcd,
- LCD_CMD_SET_DDRAM_ADDR | (priv->addr.y ? lcd->hwidth : 0) |
- /*
- * we force the cursor to stay at the end of the
- * line if it wants to go farther
- */
- ((priv->addr.x < lcd->bwidth) ? priv->addr.x & (lcd->hwidth - 1)
- : lcd->bwidth - 1));
+ /*
+ * we force the cursor to stay at the end of the
+ * line if it wants to go farther
+ */
+ addr = priv->addr.x < lcd->bwidth ? priv->addr.x & (lcd->hwidth - 1)
+ : lcd->bwidth - 1;
+ if (priv->addr.y & 1)
+ addr += lcd->hwidth;
+ if (priv->addr.y & 2)
+ addr += lcd->bwidth;
+ lcd->ops->write_cmd(lcd, LCD_CMD_SET_DDRAM_ADDR | addr);
}
static void charlcd_home(struct charlcd *lcd)
@@ -203,7 +207,7 @@ static void charlcd_clear_fast(struct charlcd *lcd)
if (lcd->ops->clear_fast)
lcd->ops->clear_fast(lcd);
else
- for (pos = 0; pos < lcd->height * lcd->hwidth; pos++)
+ for (pos = 0; pos < min(2, lcd->height) * lcd->hwidth; pos++)
lcd->ops->write_data(lcd, ' ');
charlcd_home(lcd);
--
2.7.4
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 3/5] auxdisplay: charlcd: Add support for displays with more than two lines
@ 2017-03-10 14:15 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Geert Uytterhoeven
On displays with more than two lines, the additional lines are stored in
the buffers used for the first two lines, but beyond the visible parts.
Adjust the DDRAM address calculation to cater for this.
When clearing the display, avoid writing more spaces than the actual
size of the physical buffer.
Signed-off-by: Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>
---
v2:
- No changes.
---
drivers/auxdisplay/charlcd.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index b3a84e90a268478c..cfeb049a01ef8442 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -159,15 +159,19 @@ EXPORT_SYMBOL_GPL(charlcd_poke);
static void charlcd_gotoxy(struct charlcd *lcd)
{
struct charlcd_priv *priv = to_priv(lcd);
+ unsigned int addr;
- lcd->ops->write_cmd(lcd,
- LCD_CMD_SET_DDRAM_ADDR | (priv->addr.y ? lcd->hwidth : 0) |
- /*
- * we force the cursor to stay at the end of the
- * line if it wants to go farther
- */
- ((priv->addr.x < lcd->bwidth) ? priv->addr.x & (lcd->hwidth - 1)
- : lcd->bwidth - 1));
+ /*
+ * we force the cursor to stay at the end of the
+ * line if it wants to go farther
+ */
+ addr = priv->addr.x < lcd->bwidth ? priv->addr.x & (lcd->hwidth - 1)
+ : lcd->bwidth - 1;
+ if (priv->addr.y & 1)
+ addr += lcd->hwidth;
+ if (priv->addr.y & 2)
+ addr += lcd->bwidth;
+ lcd->ops->write_cmd(lcd, LCD_CMD_SET_DDRAM_ADDR | addr);
}
static void charlcd_home(struct charlcd *lcd)
@@ -203,7 +207,7 @@ static void charlcd_clear_fast(struct charlcd *lcd)
if (lcd->ops->clear_fast)
lcd->ops->clear_fast(lcd);
else
- for (pos = 0; pos < lcd->height * lcd->hwidth; pos++)
+ for (pos = 0; pos < min(2, lcd->height) * lcd->hwidth; pos++)
lcd->ops->write_data(lcd, ' ');
charlcd_home(lcd);
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
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^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
2017-03-10 14:15 ` Geert Uytterhoeven
` (3 preceding siblings ...)
(?)
@ 2017-03-10 14:15 ` Geert Uytterhoeven
2017-03-20 15:15 ` Rob Herring
-1 siblings, 1 reply; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
Add DT bindings for an Hitachi HD44780 Character LCD Controller where
its M6800 bus interface is connected to GPIOs.
Memory-mapped configurations are not yet supported.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
Memory-mapped configurations can be supported by amending the binding to
make mandatory either the {data,enable,rs}-gpios properties, or a "reg"
(and optional "reg-names") property.
As the driver doesn't support this yet, and there are different ways to
organize the register map (some wirings use different addresses for
reading and writing, to simplify bus glue logic), this is left for a
future improvement.
v2:
- Added rationale below "---".
---
.../devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 ++++++++++++++++++++++
1 file changed, 44 insertions(+)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
diff --git a/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
new file mode 100644
index 0000000000000000..ee4054da458d412f
--- /dev/null
+++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
@@ -0,0 +1,44 @@
+DT bindings for the Hitachi HD44780 Character LCD Controller
+
+The Hitachi HD44780 Character LCD Controller is commonly used on character LCDs
+that can display one or more lines of text. It exposes an M6800 bus interface,
+which can be used in either 4-bit or 8-bit mode.
+
+Required properties:
+ - compatible: Must contain "hit,hd44780",
+ - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
+ referring to the GPIO pins connected to the data signal lines DB0-DB7
+ (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
+ - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "E" (Enable) signal line of the LCD Controller's bus
+ interface,
+ - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "RS" (Register Select) signal line of the LCD Controller's
+ bus interface,
+ - display-height: Height of the display, in character cells,
+ - display-width: Width of the display, in character cells.
+
+Optional properties:
+ - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
+ interface,
+ - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ used for enabling the LCD's backlight,
+ - internal-buffer-width: Internal buffer width (default is 40 for displays
+ with 1 or 2 lines, and display-width for displays with more than 2 lines).
+
+Example:
+
+ auxdisplay {
+ compatible = "hit,hd44780";
+
+ data-gpios = <&hc595 0 GPIO_ACTIVE_HIGH>,
+ <&hc595 1 GPIO_ACTIVE_HIGH>,
+ <&hc595 2 GPIO_ACTIVE_HIGH>,
+ <&hc595 3 GPIO_ACTIVE_HIGH>;
+ enable-gpios = <&hc595 4 GPIO_ACTIVE_HIGH>;
+ rs-gpios = <&hc595 5 GPIO_ACTIVE_HIGH>;
+
+ display-height = <2>;
+ display-width = <16>;
+ };
--
2.7.4
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 5/5] auxdisplay: Add HD44780 Character LCD support
2017-03-10 14:15 ` Geert Uytterhoeven
` (4 preceding siblings ...)
(?)
@ 2017-03-10 14:15 ` Geert Uytterhoeven
-1 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-10 14:15 UTC (permalink / raw)
To: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann
Cc: Rob Herring, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel, Geert Uytterhoeven
The Hitachi HD44780 Character LCD Controller is commonly used on
character LCDs that can display one or more lines of text.
This driver supports character LCDs connected to GPIOs, using either a
4-bit or 8-bit data bus, and provides access through the charlcd core
and /dev/lcd.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
v2:
- Drop the dependency on OF by switching to the device property API,
- Depend on GPIOLIB || COMPILE_TEST.
---
drivers/auxdisplay/Kconfig | 11 ++
drivers/auxdisplay/Makefile | 1 +
drivers/auxdisplay/hd44780.c | 325 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 337 insertions(+)
create mode 100644 drivers/auxdisplay/hd44780.c
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
index b4686380d4e3cca9..c317dc515617bf8d 100644
--- a/drivers/auxdisplay/Kconfig
+++ b/drivers/auxdisplay/Kconfig
@@ -18,6 +18,17 @@ config CHARLCD
if AUXDISPLAY
+config HD44780
+ tristate "HD44780 Character LCD support"
+ depends on GPIOLIB || COMPILE_TEST
+ select CHARLCD
+ ---help---
+ Enable support for Character LCDs using a HD44780 controller.
+ The LCD is accessible through the /dev/lcd char device (10, 156).
+ This code can either be compiled as a module, or linked into the
+ kernel and started at boot.
+ If you don't understand what all this is about, say N.
+
config KS0108
tristate "KS0108 LCD Controller"
depends on PARPORT_PC
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
index f56f45dcc78e332e..fcefa686be0fea9b 100644
--- a/drivers/auxdisplay/Makefile
+++ b/drivers/auxdisplay/Makefile
@@ -6,4 +6,5 @@ obj-$(CONFIG_CHARLCD) += charlcd.o
obj-$(CONFIG_KS0108) += ks0108.o
obj-$(CONFIG_CFAG12864B) += cfag12864b.o cfag12864bfb.o
obj-$(CONFIG_IMG_ASCII_LCD) += img-ascii-lcd.o
+obj-$(CONFIG_HD44780) += hd44780.o
obj-$(CONFIG_HT16K33) += ht16k33.o
diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
new file mode 100644
index 0000000000000000..1665ac6ef9ffcb31
--- /dev/null
+++ b/drivers/auxdisplay/hd44780.c
@@ -0,0 +1,325 @@
+/*
+ * HD44780 Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+#include <misc/charlcd.h>
+
+
+enum hd44780_pin {
+ /* Order does matter due to writing to GPIO array subsets! */
+ PIN_DATA0, /* Optional */
+ PIN_DATA1, /* Optional */
+ PIN_DATA2, /* Optional */
+ PIN_DATA3, /* Optional */
+ PIN_DATA4,
+ PIN_DATA5,
+ PIN_DATA6,
+ PIN_DATA7,
+ PIN_CTRL_RS,
+ PIN_CTRL_RW, /* Optional */
+ PIN_CTRL_E,
+ PIN_CTRL_BL, /* Optional */
+ PIN_NUM
+};
+
+struct hd44780 {
+ struct gpio_desc *pins[PIN_NUM];
+};
+
+static void hd44780_backlight(struct charlcd *lcd, int on)
+{
+ struct hd44780 *hd = lcd->drvdata;
+
+ if (hd->pins[PIN_CTRL_BL])
+ gpiod_set_value_cansleep(hd->pins[PIN_CTRL_BL], on);
+}
+
+static void hd44780_strobe_gpio(struct hd44780 *hd)
+{
+ /* Maintain the data during 20 us before the strobe */
+ udelay(20);
+
+ gpiod_set_value_cansleep(hd->pins[PIN_CTRL_E], 1);
+
+ /* Maintain the strobe during 40 us */
+ udelay(40);
+
+ gpiod_set_value_cansleep(hd->pins[PIN_CTRL_E], 0);
+}
+
+/* write to an LCD panel register in 8 bit GPIO mode */
+static void hd44780_write_gpio8(struct hd44780 *hd, u8 val, unsigned int rs)
+{
+ int values[10]; /* for DATA[0-7], RS, RW */
+ unsigned int i, n;
+
+ for (i = 0; i < 8; i++)
+ values[PIN_DATA0 + i] = !!(val & BIT(i));
+ values[PIN_CTRL_RS] = rs;
+ n = 9;
+ if (hd->pins[PIN_CTRL_RW]) {
+ values[PIN_CTRL_RW] = 0;
+ n++;
+ }
+
+ /* Present the data to the port */
+ gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA0], values);
+
+ hd44780_strobe_gpio(hd);
+}
+
+/* write to an LCD panel register in 4 bit GPIO mode */
+static void hd44780_write_gpio4(struct hd44780 *hd, u8 val, unsigned int rs)
+{
+ int values[10]; /* for DATA[0-7], RS, RW, but DATA[0-3] is unused */
+ unsigned int i, n;
+
+ /* High nibble + RS, RW */
+ for (i = 4; i < 8; i++)
+ values[PIN_DATA0 + i] = !!(val & BIT(i));
+ values[PIN_CTRL_RS] = rs;
+ n = 5;
+ if (hd->pins[PIN_CTRL_RW]) {
+ values[PIN_CTRL_RW] = 0;
+ n++;
+ }
+
+ /* Present the data to the port */
+ gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
+ &values[PIN_DATA4]);
+
+ hd44780_strobe_gpio(hd);
+
+ /* Low nibble */
+ for (i = 0; i < 4; i++)
+ values[PIN_DATA4 + i] = !!(val & BIT(i));
+
+ /* Present the data to the port */
+ gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
+ &values[PIN_DATA4]);
+
+ hd44780_strobe_gpio(hd);
+}
+
+/* Send a command to the LCD panel in 8 bit GPIO mode */
+static void hd44780_write_cmd_gpio8(struct charlcd *lcd, int cmd)
+{
+ struct hd44780 *hd = lcd->drvdata;
+
+ hd44780_write_gpio8(hd, cmd, 0);
+
+ /* The shortest command takes at least 120 us */
+ udelay(120);
+}
+
+/* Send data to the LCD panel in 8 bit GPIO mode */
+static void hd44780_write_data_gpio8(struct charlcd *lcd, int data)
+{
+ struct hd44780 *hd = lcd->drvdata;
+
+ hd44780_write_gpio8(hd, data, 1);
+
+ /* The shortest data takes at least 45 us */
+ udelay(45);
+}
+
+static const struct charlcd_ops hd44780_ops_gpio8 = {
+ .write_cmd = hd44780_write_cmd_gpio8,
+ .write_data = hd44780_write_data_gpio8,
+ .backlight = hd44780_backlight,
+};
+
+/* Send a command to the LCD panel in 4 bit GPIO mode */
+static void hd44780_write_cmd_gpio4(struct charlcd *lcd, int cmd)
+{
+ struct hd44780 *hd = lcd->drvdata;
+
+ hd44780_write_gpio4(hd, cmd, 0);
+
+ /* The shortest command takes at least 120 us */
+ udelay(120);
+}
+
+/* Send 4-bits of a command to the LCD panel in raw 4 bit GPIO mode */
+static void hd44780_write_cmd_raw_gpio4(struct charlcd *lcd, int cmd)
+{
+ int values[10]; /* for DATA[0-7], RS, RW, but DATA[0-3] is unused */
+ struct hd44780 *hd = lcd->drvdata;
+ unsigned int i, n;
+
+ /* Command nibble + RS, RW */
+ for (i = 0; i < 4; i++)
+ values[PIN_DATA4 + i] = !!(cmd & BIT(i));
+ values[PIN_CTRL_RS] = 0;
+ n = 5;
+ if (hd->pins[PIN_CTRL_RW]) {
+ values[PIN_CTRL_RW] = 0;
+ n++;
+ }
+
+ /* Present the data to the port */
+ gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
+ &values[PIN_DATA4]);
+
+ hd44780_strobe_gpio(hd);
+}
+
+/* Send data to the LCD panel in 4 bit GPIO mode */
+static void hd44780_write_data_gpio4(struct charlcd *lcd, int data)
+{
+ struct hd44780 *hd = lcd->drvdata;
+
+ hd44780_write_gpio4(hd, data, 1);
+
+ /* The shortest data takes at least 45 us */
+ udelay(45);
+}
+
+static const struct charlcd_ops hd44780_ops_gpio4 = {
+ .write_cmd = hd44780_write_cmd_gpio4,
+ .write_cmd_raw4 = hd44780_write_cmd_raw_gpio4,
+ .write_data = hd44780_write_data_gpio4,
+ .backlight = hd44780_backlight,
+};
+
+static int hd44780_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ unsigned int i, base;
+ struct charlcd *lcd;
+ struct hd44780 *hd;
+ int ifwidth, ret;
+
+ /* Required pins */
+ ifwidth = gpiod_count(dev, "data");
+ if (ifwidth < 0)
+ return ifwidth;
+
+ switch (ifwidth) {
+ case 4:
+ base = PIN_DATA4;
+ break;
+ case 8:
+ base = PIN_DATA0;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ lcd = charlcd_alloc(sizeof(struct hd44780));
+ if (!lcd)
+ return -ENOMEM;
+
+ hd = lcd->drvdata;
+
+ for (i = 0; i < ifwidth; i++) {
+ hd->pins[base + i] = devm_gpiod_get_index(dev, "data", i,
+ GPIOD_OUT_LOW);
+ if (IS_ERR(hd->pins[base + i])) {
+ ret = PTR_ERR(hd->pins[base + i]);
+ goto fail;
+ }
+ }
+
+ hd->pins[PIN_CTRL_E] = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+ if (IS_ERR(hd->pins[PIN_CTRL_E])) {
+ ret = PTR_ERR(hd->pins[PIN_CTRL_E]);
+ goto fail;
+ }
+
+ hd->pins[PIN_CTRL_RS] = devm_gpiod_get(dev, "rs", GPIOD_OUT_HIGH);
+ if (IS_ERR(hd->pins[PIN_CTRL_RS])) {
+ ret = PTR_ERR(hd->pins[PIN_CTRL_RS]);
+ goto fail;
+ }
+
+ /* Optional pins */
+ hd->pins[PIN_CTRL_RW] = devm_gpiod_get_optional(dev, "rw",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(hd->pins[PIN_CTRL_RW])) {
+ ret = PTR_ERR(hd->pins[PIN_CTRL_RW]);
+ goto fail;
+ }
+
+ hd->pins[PIN_CTRL_BL] = devm_gpiod_get_optional(dev, "backlight",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(hd->pins[PIN_CTRL_BL])) {
+ ret = PTR_ERR(hd->pins[PIN_CTRL_BL]);
+ goto fail;
+ }
+
+ /* Required properties */
+ ret = device_property_read_u32(dev, "display-height", &lcd->height);
+ if (ret)
+ goto fail;
+ ret = device_property_read_u32(dev, "display-width", &lcd->width);
+ if (ret)
+ goto fail;
+
+ /*
+ * On displays with more than two rows, the internal buffer width is
+ * usually equal to the display width
+ */
+ if (lcd->height > 2)
+ lcd->bwidth = lcd->width;
+
+ /* Optional properties */
+ device_property_read_u32(dev, "internal-buffer-width", &lcd->bwidth);
+
+ lcd->ifwidth = ifwidth;
+ lcd->ops = ifwidth == 8 ? &hd44780_ops_gpio8 : &hd44780_ops_gpio4;
+
+ ret = charlcd_register(lcd);
+ if (ret)
+ goto fail;
+
+ platform_set_drvdata(pdev, lcd);
+ return 0;
+
+fail:
+ kfree(lcd);
+ return ret;
+}
+
+static int hd44780_remove(struct platform_device *pdev)
+{
+ struct charlcd *lcd = platform_get_drvdata(pdev);
+
+ charlcd_unregister(lcd);
+ return 0;
+}
+
+static const struct of_device_id hd44780_of_match[] = {
+ { .compatible = "hit,hd44780" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, hd44780_of_match);
+
+static struct platform_driver hd44780_driver = {
+ .probe = hd44780_probe,
+ .remove = hd44780_remove,
+ .driver = {
+ .name = "hd44780",
+ .of_match_table = hd44780_of_match,
+ },
+};
+
+module_platform_driver(hd44780_driver);
+MODULE_DESCRIPTION("HD44780 Character LCD driver");
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_LICENSE("GPL");
--
2.7.4
^ permalink raw reply related [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
2017-03-10 14:15 ` [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780 Geert Uytterhoeven
@ 2017-03-20 15:15 ` Rob Herring
2017-03-20 15:27 ` Geert Uytterhoeven
0 siblings, 1 reply; 16+ messages in thread
From: Rob Herring @ 2017-03-20 15:15 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Miguel Ojeda Sandonis, Greg Kroah-Hartman, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree, linux-kernel
On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
> its M6800 bus interface is connected to GPIOs.
>
> Memory-mapped configurations are not yet supported.
>
> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
> ---
> Memory-mapped configurations can be supported by amending the binding to
> make mandatory either the {data,enable,rs}-gpios properties, or a "reg"
> (and optional "reg-names") property.
>
> As the driver doesn't support this yet, and there are different ways to
> organize the register map (some wirings use different addresses for
> reading and writing, to simplify bus glue logic), this is left for a
> future improvement.
>
> v2:
> - Added rationale below "---".
> ---
> .../devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 ++++++++++++++++++++++
> 1 file changed, 44 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>
> diff --git a/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
> new file mode 100644
> index 0000000000000000..ee4054da458d412f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
> @@ -0,0 +1,44 @@
> +DT bindings for the Hitachi HD44780 Character LCD Controller
> +
> +The Hitachi HD44780 Character LCD Controller is commonly used on character LCDs
> +that can display one or more lines of text. It exposes an M6800 bus interface,
> +which can be used in either 4-bit or 8-bit mode.
> +
> +Required properties:
> + - compatible: Must contain "hit,hd44780",
> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
> + referring to the GPIO pins connected to the data signal lines DB0-DB7
> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> + connected to the "E" (Enable) signal line of the LCD Controller's bus
> + interface,
> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> + connected to the "RS" (Register Select) signal line of the LCD Controller's
> + bus interface,
> + - display-height: Height of the display, in character cells,
> + - display-width: Width of the display, in character cells.
display-{width,height}-chars
> +
> +Optional properties:
> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
> + interface,
> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> + used for enabling the LCD's backlight,
Active state?
> + - internal-buffer-width: Internal buffer width (default is 40 for displays
> + with 1 or 2 lines, and display-width for displays with more than 2 lines).
> +
> +Example:
> +
> + auxdisplay {
> + compatible = "hit,hd44780";
> +
> + data-gpios = <&hc595 0 GPIO_ACTIVE_HIGH>,
> + <&hc595 1 GPIO_ACTIVE_HIGH>,
> + <&hc595 2 GPIO_ACTIVE_HIGH>,
> + <&hc595 3 GPIO_ACTIVE_HIGH>;
> + enable-gpios = <&hc595 4 GPIO_ACTIVE_HIGH>;
> + rs-gpios = <&hc595 5 GPIO_ACTIVE_HIGH>;
> +
> + display-height = <2>;
> + display-width = <16>;
> + };
> --
> 2.7.4
>
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
2017-03-20 15:15 ` Rob Herring
@ 2017-03-20 15:27 ` Geert Uytterhoeven
2017-03-20 15:48 ` Greg Kroah-Hartman
2017-03-20 17:00 ` Rob Herring
0 siblings, 2 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-20 15:27 UTC (permalink / raw)
To: Rob Herring, Greg Kroah-Hartman
Cc: Miguel Ojeda Sandonis, Willy Tarreau, Ksenija Stanojevic,
Arnd Bergmann, Mark Rutland, Akira Tsukamoto, devicetree,
linux-kernel
Hi Rob, Greg,
On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh@kernel.org> wrote:
> On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
>> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
>> its M6800 bus interface is connected to GPIOs.
>>
>> Memory-mapped configurations are not yet supported.
>>
>> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>> +Required properties:
>> + - compatible: Must contain "hit,hd44780",
>> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
>> + referring to the GPIO pins connected to the data signal lines DB0-DB7
>> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
>> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>> + connected to the "E" (Enable) signal line of the LCD Controller's bus
>> + interface,
>> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>> + connected to the "RS" (Register Select) signal line of the LCD Controller's
>> + bus interface,
>> + - display-height: Height of the display, in character cells,
>> + - display-width: Width of the display, in character cells.
>
> display-{width,height}-chars
Makes sense.
Greg: As this is already in char-misc-next, shall I send an update for
the bindings
and the driver?
>> +Optional properties:
>> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
>> + interface,
>> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>> + used for enabling the LCD's backlight,
>
> Active state?
That's typically handled via the last cell of the GPIO specifier, cfr.
GPIO_ACTIVE_HIGH / GPIO_ACTIVE_LOW in <dt-bindings/gpio/gpio.h>.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
2017-03-20 15:27 ` Geert Uytterhoeven
@ 2017-03-20 15:48 ` Greg Kroah-Hartman
2017-03-20 17:00 ` Rob Herring
1 sibling, 0 replies; 16+ messages in thread
From: Greg Kroah-Hartman @ 2017-03-20 15:48 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Rob Herring, Miguel Ojeda Sandonis, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree, linux-kernel
On Mon, Mar 20, 2017 at 04:27:01PM +0100, Geert Uytterhoeven wrote:
> Hi Rob, Greg,
>
> On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh@kernel.org> wrote:
> > On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
> >> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
> >> its M6800 bus interface is connected to GPIOs.
> >>
> >> Memory-mapped configurations are not yet supported.
> >>
> >> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
>
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>
> >> +Required properties:
> >> + - compatible: Must contain "hit,hd44780",
> >> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
> >> + referring to the GPIO pins connected to the data signal lines DB0-DB7
> >> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
> >> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> >> + connected to the "E" (Enable) signal line of the LCD Controller's bus
> >> + interface,
> >> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
> >> + connected to the "RS" (Register Select) signal line of the LCD Controller's
> >> + bus interface,
> >> + - display-height: Height of the display, in character cells,
> >> + - display-width: Width of the display, in character cells.
> >
> > display-{width,height}-chars
>
> Makes sense.
>
> Greg: As this is already in char-misc-next, shall I send an update for
> the bindings and the driver?
Please do.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
@ 2017-03-20 17:00 ` Rob Herring
0 siblings, 0 replies; 16+ messages in thread
From: Rob Herring @ 2017-03-20 17:00 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Greg Kroah-Hartman, Miguel Ojeda Sandonis, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree, linux-kernel
On Mon, Mar 20, 2017 at 10:27 AM, Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> Hi Rob, Greg,
>
> On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh@kernel.org> wrote:
>> On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
>>> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
>>> its M6800 bus interface is connected to GPIOs.
>>>
>>> Memory-mapped configurations are not yet supported.
>>>
>>> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
>
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>
>>> +Required properties:
>>> + - compatible: Must contain "hit,hd44780",
>>> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
>>> + referring to the GPIO pins connected to the data signal lines DB0-DB7
>>> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
>>> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "E" (Enable) signal line of the LCD Controller's bus
>>> + interface,
>>> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "RS" (Register Select) signal line of the LCD Controller's
>>> + bus interface,
>>> + - display-height: Height of the display, in character cells,
>>> + - display-width: Width of the display, in character cells.
>>
>> display-{width,height}-chars
>
> Makes sense.
>
> Greg: As this is already in char-misc-next, shall I send an update for
> the bindings
> and the driver?
>
>>> +Optional properties:
>>> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
>>> + interface,
>>> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + used for enabling the LCD's backlight,
>>
>> Active state?
>
> That's typically handled via the last cell of the GPIO specifier, cfr.
> GPIO_ACTIVE_HIGH / GPIO_ACTIVE_LOW in <dt-bindings/gpio/gpio.h>.
Yes, I know. I want to be able to read the binding and validate the
dts file, so I need to know what is the correct flag.
Rob
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
@ 2017-03-20 17:00 ` Rob Herring
0 siblings, 0 replies; 16+ messages in thread
From: Rob Herring @ 2017-03-20 17:00 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Greg Kroah-Hartman, Miguel Ojeda Sandonis, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
On Mon, Mar 20, 2017 at 10:27 AM, Geert Uytterhoeven
<geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org> wrote:
> Hi Rob, Greg,
>
> On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
>> On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
>>> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
>>> its M6800 bus interface is connected to GPIOs.
>>>
>>> Memory-mapped configurations are not yet supported.
>>>
>>> Signed-off-by: Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>
>
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>
>>> +Required properties:
>>> + - compatible: Must contain "hit,hd44780",
>>> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
>>> + referring to the GPIO pins connected to the data signal lines DB0-DB7
>>> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
>>> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "E" (Enable) signal line of the LCD Controller's bus
>>> + interface,
>>> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "RS" (Register Select) signal line of the LCD Controller's
>>> + bus interface,
>>> + - display-height: Height of the display, in character cells,
>>> + - display-width: Width of the display, in character cells.
>>
>> display-{width,height}-chars
>
> Makes sense.
>
> Greg: As this is already in char-misc-next, shall I send an update for
> the bindings
> and the driver?
>
>>> +Optional properties:
>>> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
>>> + interface,
>>> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>> + used for enabling the LCD's backlight,
>>
>> Active state?
>
> That's typically handled via the last cell of the GPIO specifier, cfr.
> GPIO_ACTIVE_HIGH / GPIO_ACTIVE_LOW in <dt-bindings/gpio/gpio.h>.
Yes, I know. I want to be able to read the binding and validate the
dts file, so I need to know what is the correct flag.
Rob
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
@ 2017-03-21 8:07 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-21 8:07 UTC (permalink / raw)
To: Rob Herring
Cc: Greg Kroah-Hartman, Miguel Ojeda Sandonis, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree, linux-kernel
Hi Rob,
On Mon, Mar 20, 2017 at 6:00 PM, Rob Herring <robh@kernel.org> wrote:
> On Mon, Mar 20, 2017 at 10:27 AM, Geert Uytterhoeven
> <geert@linux-m68k.org> wrote:
>> On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh@kernel.org> wrote:
>>> On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
>>>> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
>>>> its M6800 bus interface is connected to GPIOs.
>>>>
>>>> Memory-mapped configurations are not yet supported.
>>>>
>>>> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
>>
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>>
>>>> +Required properties:
>>>> + - compatible: Must contain "hit,hd44780",
>>>> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
>>>> + referring to the GPIO pins connected to the data signal lines DB0-DB7
>>>> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
>>>> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "E" (Enable) signal line of the LCD Controller's bus
>>>> + interface,
>>>> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "RS" (Register Select) signal line of the LCD Controller's
>>>> + bus interface,
>>>> + - display-height: Height of the display, in character cells,
>>>> + - display-width: Width of the display, in character cells.
>>>
>>> display-{width,height}-chars
>>
>> Makes sense.
>>
>> Greg: As this is already in char-misc-next, shall I send an update for
>> the bindings
>> and the driver?
>>
>>>> +Optional properties:
>>>> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
>>>> + interface,
>>>> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + used for enabling the LCD's backlight,
>>>
>>> Active state?
>>
>> That's typically handled via the last cell of the GPIO specifier, cfr.
>> GPIO_ACTIVE_HIGH / GPIO_ACTIVE_LOW in <dt-bindings/gpio/gpio.h>.
>
> Yes, I know. I want to be able to read the binding and validate the
> dts file, so I need to know what is the correct flag.
For the LCD Controller's bus, the GPIOs are wired straight, so they should
be ACTIVE_HIGH (unless there's an inverting buffer in between :-).
The backlight is separate from the LCD Controller, hence the polarity
depends on the actual hardware configuration.
Is it worth documenting that?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
@ 2017-03-21 8:07 ` Geert Uytterhoeven
0 siblings, 0 replies; 16+ messages in thread
From: Geert Uytterhoeven @ 2017-03-21 8:07 UTC (permalink / raw)
To: Rob Herring
Cc: Greg Kroah-Hartman, Miguel Ojeda Sandonis, Willy Tarreau,
Ksenija Stanojevic, Arnd Bergmann, Mark Rutland, Akira Tsukamoto,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Hi Rob,
On Mon, Mar 20, 2017 at 6:00 PM, Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
> On Mon, Mar 20, 2017 at 10:27 AM, Geert Uytterhoeven
> <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org> wrote:
>> On Mon, Mar 20, 2017 at 4:15 PM, Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
>>> On Fri, Mar 10, 2017 at 03:15:20PM +0100, Geert Uytterhoeven wrote:
>>>> Add DT bindings for an Hitachi HD44780 Character LCD Controller where
>>>> its M6800 bus interface is connected to GPIOs.
>>>>
>>>> Memory-mapped configurations are not yet supported.
>>>>
>>>> Signed-off-by: Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>
>>
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
>>
>>>> +Required properties:
>>>> + - compatible: Must contain "hit,hd44780",
>>>> + - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
>>>> + referring to the GPIO pins connected to the data signal lines DB0-DB7
>>>> + (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
>>>> + - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "E" (Enable) signal line of the LCD Controller's bus
>>>> + interface,
>>>> + - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "RS" (Register Select) signal line of the LCD Controller's
>>>> + bus interface,
>>>> + - display-height: Height of the display, in character cells,
>>>> + - display-width: Width of the display, in character cells.
>>>
>>> display-{width,height}-chars
>>
>> Makes sense.
>>
>> Greg: As this is already in char-misc-next, shall I send an update for
>> the bindings
>> and the driver?
>>
>>>> +Optional properties:
>>>> + - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
>>>> + interface,
>>>> + - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
>>>> + used for enabling the LCD's backlight,
>>>
>>> Active state?
>>
>> That's typically handled via the last cell of the GPIO specifier, cfr.
>> GPIO_ACTIVE_HIGH / GPIO_ACTIVE_LOW in <dt-bindings/gpio/gpio.h>.
>
> Yes, I know. I want to be able to read the binding and validate the
> dts file, so I need to know what is the correct flag.
For the LCD Controller's bus, the GPIOs are wired straight, so they should
be ACTIVE_HIGH (unless there's an inverting buffer in between :-).
The backlight is separate from the LCD Controller, hence the polarity
depends on the actual hardware configuration.
Is it worth documenting that?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2017-03-21 8:07 UTC | newest]
Thread overview: 16+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-03-10 14:15 [PATCH v2 0/5] Add HD44780 Character LCD support Geert Uytterhoeven
2017-03-10 14:15 ` Geert Uytterhoeven
2017-03-10 14:15 ` [PATCH v2 1/5] auxdisplay: charlcd: Extract character LCD core from misc/panel Geert Uytterhoeven
2017-03-10 14:15 ` Geert Uytterhoeven
2017-03-10 14:15 ` [PATCH v2 2/5] auxdisplay: charlcd: Add support for 4-bit interfaces Geert Uytterhoeven
2017-03-10 14:15 ` [PATCH v2 3/5] auxdisplay: charlcd: Add support for displays with more than two lines Geert Uytterhoeven
2017-03-10 14:15 ` Geert Uytterhoeven
2017-03-10 14:15 ` [PATCH v2 4/5] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780 Geert Uytterhoeven
2017-03-20 15:15 ` Rob Herring
2017-03-20 15:27 ` Geert Uytterhoeven
2017-03-20 15:48 ` Greg Kroah-Hartman
2017-03-20 17:00 ` Rob Herring
2017-03-20 17:00 ` Rob Herring
2017-03-21 8:07 ` Geert Uytterhoeven
2017-03-21 8:07 ` Geert Uytterhoeven
2017-03-10 14:15 ` [PATCH v2 5/5] auxdisplay: Add HD44780 Character LCD support Geert Uytterhoeven
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