diff options
Diffstat (limited to 'drivers/video/n411.c')
| -rw-r--r-- | drivers/video/n411.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/drivers/video/n411.c b/drivers/video/n411.c new file mode 100644 index 00000000000..935830fea7b --- /dev/null +++ b/drivers/video/n411.c @@ -0,0 +1,202 @@ +/* + * linux/drivers/video/n411.c -- Platform device for N411 EPD kit + * + * Copyright (C) 2008, Jaya Kumar + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + * + * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven. + * + * This driver is written to be used with the Hecuba display controller + * board, and tested with the EInk 800x600 display in 1 bit mode. + * The interface between Hecuba and the host is TTL based GPIO. The + * GPIO requirements are 8 writable data lines and 6 lines for control. + * Only 4 of the controls are actually used here but 6 for future use. + * The driver requires the IO addresses for data and control GPIO at + * load time. It is also possible to use this display with a standard + * PC parallel port. + * + * General notes: + * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR c2io_addr=0xIOADDR + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/fb.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/list.h> +#include <linux/uaccess.h> +#include <linux/irq.h> + +#include <video/hecubafb.h> + +static unsigned long dio_addr; +static unsigned long cio_addr; +static unsigned long c2io_addr; +static unsigned long splashval; +static unsigned int nosplash; +static unsigned char ctl; + +static void n411_set_ctl(struct hecubafb_par *par, unsigned char bit, unsigned + char state) +{ + switch (bit) { + case HCB_CD_BIT: + if (state) + ctl &= ~(HCB_CD_BIT); + else + ctl |= HCB_CD_BIT; + break; + case HCB_DS_BIT: + if (state) + ctl &= ~(HCB_DS_BIT); + else + ctl |= HCB_DS_BIT; + break; + } + outb(ctl, cio_addr); +} + +static unsigned char n411_get_ctl(struct hecubafb_par *par) +{ + return inb(c2io_addr); +} + +static void n411_set_data(struct hecubafb_par *par, unsigned char value) +{ + outb(value, dio_addr); +} + +static void n411_wait_for_ack(struct hecubafb_par *par, int clear) +{ + int timeout; + unsigned char tmp; + + timeout = 500; + do { + tmp = n411_get_ctl(par); + if ((tmp & HCB_ACK_BIT) && (!clear)) + return; + else if (!(tmp & HCB_ACK_BIT) && (clear)) + return; + udelay(1); + } while (timeout--); + printk(KERN_ERR "timed out waiting for ack\n"); +} + +static int n411_init_control(struct hecubafb_par *par) +{ + unsigned char tmp; + /* for init, we want the following setup to be set: + WUP = lo + ACK = hi + DS = hi + RW = hi + CD = lo + */ + + /* write WUP to lo, DS to hi, RW to hi, CD to lo */ + ctl = HCB_WUP_BIT | HCB_RW_BIT | HCB_CD_BIT ; + n411_set_ctl(par, HCB_DS_BIT, 1); + + /* check ACK is not lo */ + tmp = n411_get_ctl(par); + if (tmp & HCB_ACK_BIT) { + printk(KERN_ERR "Fail because ACK is already low\n"); + return -ENXIO; + } + + return 0; +} + + +static int n411_init_board(struct hecubafb_par *par) +{ + int retval; + + retval = n411_init_control(par); + if (retval) + return retval; + + par->send_command(par, APOLLO_INIT_DISPLAY); + par->send_data(par, 0x81); + + /* have to wait while display resets */ + udelay(1000); + + /* if we were told to splash the screen, we just clear it */ + if (!nosplash) { + par->send_command(par, APOLLO_ERASE_DISPLAY); + par->send_data(par, splashval); + } + + return 0; +} + +static struct hecuba_board n411_board = { + .owner = THIS_MODULE, + .init = n411_init_board, + .set_ctl = n411_set_ctl, + .set_data = n411_set_data, + .wait_for_ack = n411_wait_for_ack, +}; + +static struct platform_device *n411_device; +static int __init n411_init(void) +{ + int ret; + if (!dio_addr || !cio_addr || !c2io_addr) { + printk(KERN_WARNING "no IO addresses supplied\n"); + return -EINVAL; + } + + /* request our platform independent driver */ + request_module("hecubafb"); + + n411_device = platform_device_alloc("hecubafb", -1); + if (!n411_device) + return -ENOMEM; + + platform_device_add_data(n411_device, &n411_board, sizeof(n411_board)); + + /* this _add binds hecubafb to n411. hecubafb refcounts n411 */ + ret = platform_device_add(n411_device); + + if (ret) + platform_device_put(n411_device); + + return ret; + +} + +static void __exit n411_exit(void) +{ + platform_device_unregister(n411_device); +} + +module_init(n411_init); +module_exit(n411_exit); + +module_param(nosplash, uint, 0); +MODULE_PARM_DESC(nosplash, "Disable doing the splash screen"); +module_param(dio_addr, ulong, 0); +MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480"); +module_param(cio_addr, ulong, 0); +MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400"); +module_param(c2io_addr, ulong, 0); +MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408"); +module_param(splashval, ulong, 0); +MODULE_PARM_DESC(splashval, "Splash pattern: 0x00 is black, 0x01 is white"); + +MODULE_DESCRIPTION("board driver for n411 hecuba/apollo epd kit"); +MODULE_AUTHOR("Jaya Kumar"); +MODULE_LICENSE("GPL"); + |