am300epd.c
/*
* am300epd.c -- Platform device for AM300 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.
*
* This work was made possible by help and equipment support from E-Ink
* Corporation. http://support.eink.com/community
*
* This driver is written to be used with the Broadsheet display controller.
* on the AM300 EPD prototype kit/development kit with an E-Ink 800x600
* Vizplex EPD on a Gumstix board using the Broadsheet interface board.
*
*/
#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/irq.h>
#include <linux/gpio.h>
#include <mach/gumstix.h>
#include <mach/mfp-pxa25x.h>
#include <mach/pxafb.h>
#include "generic.h"
#include <video/broadsheetfb.h>
static unsigned int panel_type = 6;
static struct platform_device *am300_device;
static struct broadsheet_board am300_board;
static unsigned long am300_pin_config[] __initdata = {
GPIO16_GPIO,
GPIO17_GPIO,
GPIO32_GPIO,
GPIO48_GPIO,
GPIO49_GPIO,
GPIO51_GPIO,
GPIO74_GPIO,
GPIO75_GPIO,
GPIO76_GPIO,
GPIO77_GPIO,
/* this is the 16-bit hdb bus 58-73 */
GPIO58_GPIO,
GPIO59_GPIO,
GPIO60_GPIO,
GPIO61_GPIO,
GPIO62_GPIO,
GPIO63_GPIO,
GPIO64_GPIO,
GPIO65_GPIO,
GPIO66_GPIO,
GPIO67_GPIO,
GPIO68_GPIO,
GPIO69_GPIO,
GPIO70_GPIO,
GPIO71_GPIO,
GPIO72_GPIO,
GPIO73_GPIO,
};
/* register offsets for gpio control */
#define PWR_GPIO_PIN 16
#define CFG_GPIO_PIN 17
#define RDY_GPIO_PIN 32
#define DC_GPIO_PIN 48
#define RST_GPIO_PIN 49
#define LED_GPIO_PIN 51
#define RD_GPIO_PIN 74
#define WR_GPIO_PIN 75
#define CS_GPIO_PIN 76
#define IRQ_GPIO_PIN 77
/* hdb bus */
#define DB0_GPIO_PIN 58
#define DB15_GPIO_PIN 73
static int gpios[] = { PWR_GPIO_PIN, CFG_GPIO_PIN, RDY_GPIO_PIN, DC_GPIO_PIN,
RST_GPIO_PIN, RD_GPIO_PIN, WR_GPIO_PIN, CS_GPIO_PIN,
IRQ_GPIO_PIN, LED_GPIO_PIN };
static char *gpio_names[] = { "PWR", "CFG", "RDY", "DC", "RST", "RD", "WR",
"CS", "IRQ", "LED" };
static int am300_wait_event(struct broadsheetfb_par *par)
{
/* todo: improve err recovery */
wait_event(par->waitq, gpio_get_value(RDY_GPIO_PIN));
return 0;
}
static int am300_init_gpio_regs(struct broadsheetfb_par *par)
{
int i;
int err;
char dbname[8];
for (i = 0; i < ARRAY_SIZE(gpios); i++) {
err = gpio_request(gpios[i], gpio_names[i]);
if (err) {
dev_err(&am300_device->dev, "failed requesting "
"gpio %s, err=%d\n", gpio_names[i], err);
goto err_req_gpio;
}
}
/* we also need to take care of the hdb bus */
for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++) {
sprintf(dbname, "DB%d", i);
err = gpio_request(i, dbname);
if (err) {
dev_err(&am300_device->dev, "failed requesting "
"gpio %d, err=%d\n", i, err);
goto err_req_gpio2;
}
}
/* setup the outputs and init values */
gpio_direction_output(PWR_GPIO_PIN, 0);
gpio_direction_output(CFG_GPIO_PIN, 1);
gpio_direction_output(DC_GPIO_PIN, 0);
gpio_direction_output(RD_GPIO_PIN, 1);
gpio_direction_output(WR_GPIO_PIN, 1);
gpio_direction_output(CS_GPIO_PIN, 1);
gpio_direction_output(RST_GPIO_PIN, 0);
/* setup the inputs */
gpio_direction_input(RDY_GPIO_PIN);
gpio_direction_input(IRQ_GPIO_PIN);
/* start the hdb bus as an input */
for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++)
gpio_direction_output(i, 0);
/* go into command mode */
gpio_set_value(CFG_GPIO_PIN, 1);
gpio_set_value(RST_GPIO_PIN, 0);
msleep(10);
gpio_set_value(RST_GPIO_PIN, 1);
msleep(10);
am300_wait_event(par);
return 0;
err_req_gpio2:
while (--i >= DB0_GPIO_PIN)
gpio_free(i);
i = ARRAY_SIZE(gpios);
err_req_gpio:
while (--i >= 0)
gpio_free(gpios[i]);
return err;
}
static int am300_init_board(struct broadsheetfb_par *par)
{
return am300_init_gpio_regs(par);
}
static void am300_cleanup(struct broadsheetfb_par *par)
{
int i;
free_irq(IRQ_GPIO(RDY_GPIO_PIN), par);
for (i = 0; i < ARRAY_SIZE(gpios); i++)
gpio_free(gpios[i]);
for (i = DB0_GPIO_PIN; i <= DB15_GPIO_PIN; i++)
gpio_free(i);
}
static u16 am300_get_hdb(struct broadsheetfb_par *par)
{
u16 res = 0;
int i;
for (i = 0; i <= (DB15_GPIO_PIN - DB0_GPIO_PIN) ; i++)
res |= (gpio_get_value(DB0_GPIO_PIN + i)) ? (1 << i) : 0;
return res;
}
static void am300_set_hdb(struct broadsheetfb_par *par, u16 data)
{
int i;
for (i = 0; i <= (DB15_GPIO_PIN - DB0_GPIO_PIN) ; i++)
gpio_set_value(DB0_GPIO_PIN + i, (data >> i) & 0x01);
}
static void am300_set_ctl(struct broadsheetfb_par *par, unsigned char bit,
u8 state)
{
switch (bit) {
case BS_CS:
gpio_set_value(CS_GPIO_PIN, state);
break;
case BS_DC:
gpio_set_value(DC_GPIO_PIN, state);
break;
case BS_WR:
gpio_set_value(WR_GPIO_PIN, state);
break;
}
}
static int am300_get_panel_type(void)
{
return panel_type;
}
static irqreturn_t am300_handle_irq(int irq, void *dev_id)
{
struct broadsheetfb_par *par = dev_id;
wake_up(&par->waitq);
return IRQ_HANDLED;
}
static int am300_setup_irq(struct fb_info *info)
{
int ret;
struct broadsheetfb_par *par = info->par;
ret = request_irq(IRQ_GPIO(RDY_GPIO_PIN), am300_handle_irq,
IRQF_DISABLED|IRQF_TRIGGER_RISING,
"AM300", par);
if (ret)
dev_err(&am300_device->dev, "request_irq failed: %d\n", ret);
return ret;
}
static struct broadsheet_board am300_board = {
.owner = THIS_MODULE,
.init = am300_init_board,
.cleanup = am300_cleanup,
.set_hdb = am300_set_hdb,
.get_hdb = am300_get_hdb,
.set_ctl = am300_set_ctl,
.wait_for_rdy = am300_wait_event,
.get_panel_type = am300_get_panel_type,
.setup_irq = am300_setup_irq,
};
int __init am300_init(void)
{
int ret;
pxa2xx_mfp_config(ARRAY_AND_SIZE(am300_pin_config));
/* request our platform independent driver */
request_module("broadsheetfb");
am300_device = platform_device_alloc("broadsheetfb", -1);
if (!am300_device)
return -ENOMEM;
/* the am300_board that will be seen by broadsheetfb is a copy */
platform_device_add_data(am300_device, &am300_board,
sizeof(am300_board));
ret = platform_device_add(am300_device);
if (ret) {
platform_device_put(am300_device);
return ret;
}
return 0;
}
module_param(panel_type, uint, 0);
MODULE_PARM_DESC(panel_type, "Select the panel type: 37, 6, 97");
MODULE_DESCRIPTION("board driver for am300 epd kit");
MODULE_AUTHOR("Jaya Kumar");
MODULE_LICENSE("GPL");