[PATCH] drivers: add LCD support
Add support for auxiliary displays, the ks0108 LCD controller, the
cfag12864b LCD and adds a framebuffer device: cfag12864bfb.
- Add a "auxdisplay/" folder in "drivers/" for auxiliary display
drivers.
- Add support for the ks0108 LCD Controller as a device driver. (uses
parport interface)
- Add support for the cfag12864b LCD as a device driver. (uses ks0108
LCD Controller driver)
- Add a framebuffer device called cfag12864bfb. (uses cfag12864b LCD
driver)
- Add the usual Documentation, includes, Makefiles, Kconfigs,
MAINTAINERS, CREDITS...
- Miguel Ojeda will maintain all the stuff above.
[rdunlap@xenotime.net: workqueue fixups]
[akpm@osdl.org: kconfig fix]
Signed-off-by: Miguel Ojeda Sandonis <maxextreme@gmail.com>
Cc: Greg KH <greg@kroah.com>
Acked-by: Paulo Marques <pmarques@grupopie.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
new file mode 100644
index 0000000..0300e7f5
--- /dev/null
+++ b/drivers/auxdisplay/Kconfig
@@ -0,0 +1,109 @@
+#
+# For a description of the syntax of this configuration file,
+# see Documentation/kbuild/kconfig-language.txt.
+#
+# Auxiliary display drivers configuration.
+#
+
+menu "Auxiliary Display support"
+
+config KS0108
+ tristate "KS0108 LCD Controller"
+ depends on PARPORT_PC
+ default n
+ ---help---
+ If you have a LCD controlled by one or more KS0108
+ controllers, say Y. You will need also another more specific
+ driver for your LCD.
+
+ Depends on Parallel Port support. If you say Y at
+ parport, you will be able to compile this as a module (M)
+ and built-in as well (Y).
+
+ To compile this as a module, choose M here:
+ the module will be called ks0108.
+
+ If unsure, say N.
+
+config KS0108_PORT
+ hex "Parallel port where the LCD is connected"
+ depends on KS0108
+ default 0x378
+ ---help---
+ The address of the parallel port where the LCD is connected.
+
+ The first standard parallel port address is 0x378.
+ The second standard parallel port address is 0x278.
+ The third standard parallel port address is 0x3BC.
+
+ You can specify a different address if you need.
+
+ If you don't know what I'm talking about, load the parport module,
+ and execute "dmesg" or "cat /proc/ioports". You can see there how
+ many parallel ports are present and which address each one has.
+
+ Usually you only need to use 0x378.
+
+ If you compile this as a module, you can still override this
+ using the module parameters.
+
+config KS0108_DELAY
+ int "Delay between each control writing (microseconds)"
+ depends on KS0108
+ default "2"
+ ---help---
+ Amount of time the ks0108 should wait between each control write
+ to the parallel port.
+
+ If your driver seems to miss random writings, increment this.
+
+ If you don't know what I'm talking about, ignore it.
+
+ If you compile this as a module, you can still override this
+ value using the module parameters.
+
+config CFAG12864B
+ tristate "CFAG12864B LCD"
+ depends on X86
+ depends on FB
+ depends on KS0108
+ default n
+ ---help---
+ If you have a Crystalfontz 128x64 2-color LCD, cfag12864b Series,
+ say Y. You also need the ks0108 LCD Controller driver.
+
+ For help about how to wire your LCD to the parallel port,
+ check Documentation/auxdisplay/cfag12864b
+
+ Depends on the x86 arch and the framebuffer support.
+
+ The LCD framebuffer driver can be attached to a console.
+ It will work fine. However, you can't attach it to the fbdev driver
+ of the xorg server.
+
+ To compile this as a module, choose M here:
+ the modules will be called cfag12864b and cfag12864bfb.
+
+ If unsure, say N.
+
+config CFAG12864B_RATE
+ int "Refresh rate (hertz)"
+ depends on CFAG12864B
+ default "20"
+ ---help---
+ Refresh rate of the LCD.
+
+ As the LCD is not memory mapped, the driver has to make the work by
+ software. This means you should be careful setting this value higher.
+ If your CPUs are really slow or you feel the system is slowed down,
+ decrease the value.
+
+ Be careful modifying this value to a very high value:
+ You can freeze the computer, or the LCD maybe can't draw as fast as you
+ are requesting.
+
+ If you don't know what I'm talking about, ignore it.
+
+ If you compile this as a module, you can still override this
+ value using the module parameters.
+endmenu
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
new file mode 100644
index 0000000..8a8936a
--- /dev/null
+++ b/drivers/auxdisplay/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the kernel auxiliary displays device drivers.
+#
+
+obj-$(CONFIG_KS0108) += ks0108.o
+obj-$(CONFIG_CFAG12864B) += cfag12864b.o cfag12864bfb.o
diff --git a/drivers/auxdisplay/cfag12864b.c b/drivers/auxdisplay/cfag12864b.c
new file mode 100644
index 0000000..889583d
--- /dev/null
+++ b/drivers/auxdisplay/cfag12864b.c
@@ -0,0 +1,383 @@
+/*
+ * Filename: cfag12864b.c
+ * Version: 0.1.0
+ * Description: cfag12864b LCD driver
+ * License: GPLv2
+ * Depends: ks0108
+ *
+ * Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
+ * Date: 2006-10-31
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/workqueue.h>
+#include <linux/ks0108.h>
+#include <linux/cfag12864b.h>
+
+
+#define CFAG12864B_NAME "cfag12864b"
+
+/*
+ * Module Parameters
+ */
+
+static unsigned int cfag12864b_rate = CONFIG_CFAG12864B_RATE;
+module_param(cfag12864b_rate, uint, S_IRUGO);
+MODULE_PARM_DESC(cfag12864b_rate,
+ "Refresh rate (hertzs)");
+
+unsigned int cfag12864b_getrate(void)
+{
+ return cfag12864b_rate;
+}
+
+/*
+ * cfag12864b Commands
+ *
+ * E = Enable signal
+ * Everytime E switch from low to high,
+ * cfag12864b/ks0108 reads the command/data.
+ *
+ * CS1 = First ks0108controller.
+ * If high, the first ks0108 controller receives commands/data.
+ *
+ * CS2 = Second ks0108 controller
+ * If high, the second ks0108 controller receives commands/data.
+ *
+ * DI = Data/Instruction
+ * If low, cfag12864b will expect commands.
+ * If high, cfag12864b will expect data.
+ *
+ */
+
+#define bit(n) (((unsigned char)1)<<(n))
+
+#define CFAG12864B_BIT_E (0)
+#define CFAG12864B_BIT_CS1 (2)
+#define CFAG12864B_BIT_CS2 (1)
+#define CFAG12864B_BIT_DI (3)
+
+static unsigned char cfag12864b_state;
+
+static void cfag12864b_set(void)
+{
+ ks0108_writecontrol(cfag12864b_state);
+}
+
+static void cfag12864b_setbit(unsigned char state, unsigned char n)
+{
+ if (state)
+ cfag12864b_state |= bit(n);
+ else
+ cfag12864b_state &= ~bit(n);
+}
+
+static void cfag12864b_e(unsigned char state)
+{
+ cfag12864b_setbit(state, CFAG12864B_BIT_E);
+ cfag12864b_set();
+}
+
+static void cfag12864b_cs1(unsigned char state)
+{
+ cfag12864b_setbit(state, CFAG12864B_BIT_CS1);
+}
+
+static void cfag12864b_cs2(unsigned char state)
+{
+ cfag12864b_setbit(state, CFAG12864B_BIT_CS2);
+}
+
+static void cfag12864b_di(unsigned char state)
+{
+ cfag12864b_setbit(state, CFAG12864B_BIT_DI);
+}
+
+static void cfag12864b_setcontrollers(unsigned char first,
+ unsigned char second)
+{
+ if (first)
+ cfag12864b_cs1(0);
+ else
+ cfag12864b_cs1(1);
+
+ if (second)
+ cfag12864b_cs2(0);
+ else
+ cfag12864b_cs2(1);
+}
+
+static void cfag12864b_controller(unsigned char which)
+{
+ if (which == 0)
+ cfag12864b_setcontrollers(1, 0);
+ else if (which == 1)
+ cfag12864b_setcontrollers(0, 1);
+}
+
+static void cfag12864b_displaystate(unsigned char state)
+{
+ cfag12864b_di(0);
+ cfag12864b_e(1);
+ ks0108_displaystate(state);
+ cfag12864b_e(0);
+}
+
+static void cfag12864b_address(unsigned char address)
+{
+ cfag12864b_di(0);
+ cfag12864b_e(1);
+ ks0108_address(address);
+ cfag12864b_e(0);
+}
+
+static void cfag12864b_page(unsigned char page)
+{
+ cfag12864b_di(0);
+ cfag12864b_e(1);
+ ks0108_page(page);
+ cfag12864b_e(0);
+}
+
+static void cfag12864b_startline(unsigned char startline)
+{
+ cfag12864b_di(0);
+ cfag12864b_e(1);
+ ks0108_startline(startline);
+ cfag12864b_e(0);
+}
+
+static void cfag12864b_writebyte(unsigned char byte)
+{
+ cfag12864b_di(1);
+ cfag12864b_e(1);
+ ks0108_writedata(byte);
+ cfag12864b_e(0);
+}
+
+static void cfag12864b_nop(void)
+{
+ cfag12864b_startline(0);
+}
+
+/*
+ * cfag12864b Internal Commands
+ */
+
+static void cfag12864b_on(void)
+{
+ cfag12864b_setcontrollers(1, 1);
+ cfag12864b_displaystate(1);
+}
+
+static void cfag12864b_off(void)
+{
+ cfag12864b_setcontrollers(1, 1);
+ cfag12864b_displaystate(0);
+}
+
+static void cfag12864b_clear(void)
+{
+ unsigned char i, j;
+
+ cfag12864b_setcontrollers(1, 1);
+ for (i = 0; i < CFAG12864B_PAGES; i++) {
+ cfag12864b_page(i);
+ cfag12864b_address(0);
+ for (j = 0; j < CFAG12864B_ADDRESSES; j++)
+ cfag12864b_writebyte(0);
+ }
+}
+
+/*
+ * Update work
+ */
+
+unsigned char *cfag12864b_buffer;
+static unsigned char *cfag12864b_cache;
+static DEFINE_MUTEX(cfag12864b_mutex);
+static unsigned char cfag12864b_updating;
+static void cfag12864b_update(struct work_struct *delayed_work);
+static struct workqueue_struct *cfag12864b_workqueue;
+static DECLARE_DELAYED_WORK(cfag12864b_work, cfag12864b_update);
+
+static void cfag12864b_queue(void)
+{
+ queue_delayed_work(cfag12864b_workqueue, &cfag12864b_work,
+ HZ / cfag12864b_rate);
+}
+
+unsigned char cfag12864b_enable(void)
+{
+ unsigned char ret;
+
+ mutex_lock(&cfag12864b_mutex);
+
+ if (!cfag12864b_updating) {
+ cfag12864b_updating = 1;
+ cfag12864b_queue();
+ ret = 0;
+ } else
+ ret = 1;
+
+ mutex_unlock(&cfag12864b_mutex);
+
+ return ret;
+}
+
+void cfag12864b_disable(void)
+{
+ mutex_lock(&cfag12864b_mutex);
+
+ if (cfag12864b_updating) {
+ cfag12864b_updating = 0;
+ cancel_delayed_work(&cfag12864b_work);
+ flush_workqueue(cfag12864b_workqueue);
+ }
+
+ mutex_unlock(&cfag12864b_mutex);
+}
+
+unsigned char cfag12864b_isenabled(void)
+{
+ return cfag12864b_updating;
+}
+
+static void cfag12864b_update(struct work_struct *work)
+{
+ unsigned char c;
+ unsigned short i, j, k, b;
+
+ if (memcmp(cfag12864b_cache, cfag12864b_buffer, CFAG12864B_SIZE)) {
+ for (i = 0; i < CFAG12864B_CONTROLLERS; i++) {
+ cfag12864b_controller(i);
+ cfag12864b_nop();
+ for (j = 0; j < CFAG12864B_PAGES; j++) {
+ cfag12864b_page(j);
+ cfag12864b_nop();
+ cfag12864b_address(0);
+ cfag12864b_nop();
+ for (k = 0; k < CFAG12864B_ADDRESSES; k++) {
+ for (c = 0, b = 0; b < 8; b++)
+ if (cfag12864b_buffer
+ [i * CFAG12864B_ADDRESSES / 8
+ + k / 8 + (j * 8 + b) *
+ CFAG12864B_WIDTH / 8]
+ & bit(k % 8))
+ c |= bit(b);
+ cfag12864b_writebyte(c);
+ }
+ }
+ }
+
+ memcpy(cfag12864b_cache, cfag12864b_buffer, CFAG12864B_SIZE);
+ }
+
+ if (cfag12864b_updating)
+ cfag12864b_queue();
+}
+
+/*
+ * cfag12864b Exported Symbols
+ */
+
+EXPORT_SYMBOL_GPL(cfag12864b_buffer);
+EXPORT_SYMBOL_GPL(cfag12864b_getrate);
+EXPORT_SYMBOL_GPL(cfag12864b_enable);
+EXPORT_SYMBOL_GPL(cfag12864b_disable);
+EXPORT_SYMBOL_GPL(cfag12864b_isenabled);
+
+/*
+ * Module Init & Exit
+ */
+
+static int __init cfag12864b_init(void)
+{
+ int ret = -EINVAL;
+
+ if (PAGE_SIZE < CFAG12864B_SIZE) {
+ printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+ "page size (%i) < cfag12864b size (%i)\n",
+ (unsigned int)PAGE_SIZE, CFAG12864B_SIZE);
+ ret = -ENOMEM;
+ goto none;
+ }
+
+ cfag12864b_buffer = (unsigned char *) __get_free_page(GFP_KERNEL);
+ if (cfag12864b_buffer == NULL) {
+ printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+ "can't get a free page\n");
+ ret = -ENOMEM;
+ goto none;
+ }
+
+ cfag12864b_cache = kmalloc(sizeof(unsigned char) *
+ CFAG12864B_SIZE, GFP_KERNEL);
+ if (cfag12864b_buffer == NULL) {
+ printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+ "can't alloc cache buffer (%i bytes)\n",
+ CFAG12864B_SIZE);
+ ret = -ENOMEM;
+ goto bufferalloced;
+ }
+
+ cfag12864b_workqueue = create_singlethread_workqueue(CFAG12864B_NAME);
+ if (cfag12864b_workqueue == NULL)
+ goto cachealloced;
+
+ memset(cfag12864b_buffer, 0, CFAG12864B_SIZE);
+
+ cfag12864b_clear();
+ cfag12864b_on();
+
+ return 0;
+
+cachealloced:
+ kfree(cfag12864b_cache);
+
+bufferalloced:
+ free_page((unsigned long) cfag12864b_buffer);
+
+none:
+ return ret;
+}
+
+static void __exit cfag12864b_exit(void)
+{
+ cfag12864b_disable();
+ cfag12864b_off();
+ destroy_workqueue(cfag12864b_workqueue);
+ kfree(cfag12864b_cache);
+ free_page((unsigned long) cfag12864b_buffer);
+}
+
+module_init(cfag12864b_init);
+module_exit(cfag12864b_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda Sandonis <maxextreme@gmail.com>");
+MODULE_DESCRIPTION("cfag12864b LCD driver");
diff --git a/drivers/auxdisplay/cfag12864bfb.c b/drivers/auxdisplay/cfag12864bfb.c
new file mode 100644
index 0000000..94765e7
--- /dev/null
+++ b/drivers/auxdisplay/cfag12864bfb.c
@@ -0,0 +1,180 @@
+/*
+ * Filename: cfag12864bfb.c
+ * Version: 0.1.0
+ * Description: cfag12864b LCD framebuffer driver
+ * License: GPLv2
+ * Depends: cfag12864b
+ *
+ * Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
+ * Date: 2006-10-31
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/mm.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/cfag12864b.h>
+
+#define CFAG12864BFB_NAME "cfag12864bfb"
+
+static struct fb_fix_screeninfo cfag12864bfb_fix __initdata = {
+ .id = "cfag12864b",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_MONO10,
+ .xpanstep = 0,
+ .ypanstep = 0,
+ .ywrapstep = 0,
+ .line_length = CFAG12864B_WIDTH / 8,
+ .accel = FB_ACCEL_NONE,
+};
+
+static struct fb_var_screeninfo cfag12864bfb_var __initdata = {
+ .xres = CFAG12864B_WIDTH,
+ .yres = CFAG12864B_HEIGHT,
+ .xres_virtual = CFAG12864B_WIDTH,
+ .yres_virtual = CFAG12864B_HEIGHT,
+ .bits_per_pixel = 1,
+ .red = { 0, 1, 0 },
+ .green = { 0, 1, 0 },
+ .blue = { 0, 1, 0 },
+ .left_margin = 0,
+ .right_margin = 0,
+ .upper_margin = 0,
+ .lower_margin = 0,
+ .vmode = FB_VMODE_NONINTERLACED,
+};
+
+static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+ return vm_insert_page(vma, vma->vm_start,
+ virt_to_page(cfag12864b_buffer));
+}
+
+static struct fb_ops cfag12864bfb_ops = {
+ .owner = THIS_MODULE,
+ .fb_fillrect = cfb_fillrect,
+ .fb_copyarea = cfb_copyarea,
+ .fb_imageblit = cfb_imageblit,
+ .fb_mmap = cfag12864bfb_mmap,
+};
+
+static int __init cfag12864bfb_probe(struct platform_device *device)
+{
+ int ret = -EINVAL;
+ struct fb_info *info = framebuffer_alloc(0, &device->dev);
+
+ if (!info)
+ goto none;
+
+ info->screen_base = (char __iomem *) cfag12864b_buffer;
+ info->screen_size = CFAG12864B_SIZE;
+ info->fbops = &cfag12864bfb_ops;
+ info->fix = cfag12864bfb_fix;
+ info->var = cfag12864bfb_var;
+ info->pseudo_palette = NULL;
+ info->par = NULL;
+ info->flags = FBINFO_FLAG_DEFAULT;
+
+ if (register_framebuffer(info) < 0)
+ goto fballoced;
+
+ platform_set_drvdata(device, info);
+
+ printk(KERN_INFO "fb%d: %s frame buffer device\n", info->node,
+ info->fix.id);
+
+ return 0;
+
+fballoced:
+ framebuffer_release(info);
+
+none:
+ return ret;
+}
+
+static int cfag12864bfb_remove(struct platform_device *device)
+{
+ struct fb_info *info = platform_get_drvdata(device);
+
+ if (info) {
+ unregister_framebuffer(info);
+ framebuffer_release(info);
+ }
+
+ return 0;
+}
+
+static struct platform_driver cfag12864bfb_driver = {
+ .probe = cfag12864bfb_probe,
+ .remove = cfag12864bfb_remove,
+ .driver = {
+ .name = CFAG12864BFB_NAME,
+ },
+};
+
+static struct platform_device *cfag12864bfb_device;
+
+static int __init cfag12864bfb_init(void)
+{
+ int ret;
+
+ if (cfag12864b_enable()) {
+ printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
+ "can't enable cfag12864b refreshing (being used)\n");
+ return -ENODEV;
+ }
+
+ ret = platform_driver_register(&cfag12864bfb_driver);
+
+ if (!ret) {
+ cfag12864bfb_device =
+ platform_device_alloc(CFAG12864BFB_NAME, 0);
+
+ if (cfag12864bfb_device)
+ ret = platform_device_add(cfag12864bfb_device);
+ else
+ ret = -ENOMEM;
+
+ if (ret) {
+ platform_device_put(cfag12864bfb_device);
+ platform_driver_unregister(&cfag12864bfb_driver);
+ }
+ }
+
+ return ret;
+}
+
+static void __exit cfag12864bfb_exit(void)
+{
+ platform_device_unregister(cfag12864bfb_device);
+ platform_driver_unregister(&cfag12864bfb_driver);
+ cfag12864b_disable();
+}
+
+module_init(cfag12864bfb_init);
+module_exit(cfag12864bfb_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda Sandonis <maxextreme@gmail.com>");
+MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");
diff --git a/drivers/auxdisplay/ks0108.c b/drivers/auxdisplay/ks0108.c
new file mode 100644
index 0000000..a637575
--- /dev/null
+++ b/drivers/auxdisplay/ks0108.c
@@ -0,0 +1,166 @@
+/*
+ * Filename: ks0108.c
+ * Version: 0.1.0
+ * Description: ks0108 LCD Controller driver
+ * License: GPLv2
+ * Depends: parport
+ *
+ * Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
+ * Date: 2006-10-31
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/parport.h>
+#include <linux/uaccess.h>
+#include <linux/ks0108.h>
+
+#define KS0108_NAME "ks0108"
+
+/*
+ * Module Parameters
+ */
+
+static unsigned int ks0108_port = CONFIG_KS0108_PORT;
+module_param(ks0108_port, uint, S_IRUGO);
+MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected");
+
+static unsigned int ks0108_delay = CONFIG_KS0108_DELAY;
+module_param(ks0108_delay, uint, S_IRUGO);
+MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)");
+
+/*
+ * Device
+ */
+
+static struct parport *ks0108_parport;
+static struct pardevice *ks0108_pardevice;
+
+/*
+ * ks0108 Exported Commands (don't lock)
+ *
+ * You _should_ lock in the top driver: This functions _should not_
+ * get race conditions in any way. Locking for each byte here would be
+ * so slow and useless.
+ *
+ * There are not bit definitions because they are not flags,
+ * just arbitrary combinations defined by the documentation for each
+ * function in the ks0108 LCD controller. If you want to know what means
+ * a specific combination, look at the function's name.
+ *
+ * The ks0108_writecontrol bits need to be reverted ^(0,1,3) because
+ * the parallel port also revert them using a "not" logic gate.
+ */
+
+#define bit(n) (((unsigned char)1)<<(n))
+
+void ks0108_writedata(unsigned char byte)
+{
+ parport_write_data(ks0108_parport, byte);
+}
+
+void ks0108_writecontrol(unsigned char byte)
+{
+ udelay(ks0108_delay);
+ parport_write_control(ks0108_parport, byte ^ (bit(0) | bit(1) | bit(3)));
+}
+
+void ks0108_displaystate(unsigned char state)
+{
+ ks0108_writedata((state ? bit(0) : 0) | bit(1) | bit(2) | bit(3) | bit(4) | bit(5));
+}
+
+void ks0108_startline(unsigned char startline)
+{
+ ks0108_writedata(min(startline,(unsigned char)63) | bit(6) | bit(7));
+}
+
+void ks0108_address(unsigned char address)
+{
+ ks0108_writedata(min(address,(unsigned char)63) | bit(6));
+}
+
+void ks0108_page(unsigned char page)
+{
+ ks0108_writedata(min(page,(unsigned char)7) | bit(3) | bit(4) | bit(5) | bit(7));
+}
+
+EXPORT_SYMBOL_GPL(ks0108_writedata);
+EXPORT_SYMBOL_GPL(ks0108_writecontrol);
+EXPORT_SYMBOL_GPL(ks0108_displaystate);
+EXPORT_SYMBOL_GPL(ks0108_startline);
+EXPORT_SYMBOL_GPL(ks0108_address);
+EXPORT_SYMBOL_GPL(ks0108_page);
+
+/*
+ * Module Init & Exit
+ */
+
+static int __init ks0108_init(void)
+{
+ int result;
+ int ret = -EINVAL;
+
+ ks0108_parport = parport_find_base(ks0108_port);
+ if (ks0108_parport == NULL) {
+ printk(KERN_ERR KS0108_NAME ": ERROR: "
+ "parport didn't find %i port\n", ks0108_port);
+ goto none;
+ }
+
+ ks0108_pardevice = parport_register_device(ks0108_parport, KS0108_NAME,
+ NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);
+ if (ks0108_pardevice == NULL) {
+ printk(KERN_ERR KS0108_NAME ": ERROR: "
+ "parport didn't register new device\n");
+ goto none;
+ }
+
+ result = parport_claim(ks0108_pardevice);
+ if (result != 0) {
+ printk(KERN_ERR KS0108_NAME ": ERROR: "
+ "can't claim %i parport, maybe in use\n", ks0108_port);
+ ret = result;
+ goto registered;
+ }
+
+ return 0;
+
+registered:
+ parport_unregister_device(ks0108_pardevice);
+
+none:
+ return ret;
+}
+
+static void __exit ks0108_exit(void)
+{
+ parport_release(ks0108_pardevice);
+ parport_unregister_device(ks0108_pardevice);
+}
+
+module_init(ks0108_init);
+module_exit(ks0108_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda Sandonis <maxextreme@gmail.com>");
+MODULE_DESCRIPTION("ks0108 LCD Controller driver");
+