/*
* SSP control code for Sharp Corgi devices
*
* Copyright (c) 2004 Richard Purdie
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <asm/hardware.h>
#include <asm/arch/ssp.h>
#include <asm/arch/corgi.h>
#include <asm/arch/pxa-regs.h>
static spinlock_t corgi_ssp_lock = SPIN_LOCK_UNLOCKED;
static struct ssp_dev corgi_ssp_dev;
static struct ssp_state corgi_ssp_state;
/*
* There are three devices connected to the SSP interface:
* 1. A touchscreen controller (TI ADS7846 compatible)
* 2. An LCD contoller (with some Backlight functionality)
* 3. A battery moinitoring IC (Maxim MAX1111)
*
* Each device uses a different speed/mode of communication.
*
* The touchscreen is very sensitive and the most frequently used
* so the port is left configured for this.
*
* Devices are selected using Chip Selects on GPIOs.
*/
/*
* ADS7846 Routines
*/
unsigned long corgi_ssp_ads7846_putget(ulong data)
{
unsigned long ret,flag;
spin_lock_irqsave(&corgi_ssp_lock, flag);
GPCR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS);
ssp_write_word(&corgi_ssp_dev,data);
ret = ssp_read_word(&corgi_ssp_dev);
GPSR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS);
spin_unlock_irqrestore(&corgi_ssp_lock, flag);
return ret;
}
/*
* NOTE: These functions should always be called in interrupt context
* and use the _lock and _unlock functions. They are very time sensitive.
*/
void corgi_ssp_ads7846_lock(void)
{
spin_lock(&corgi_ssp_lock);
GPCR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS);
}
void corgi_ssp_ads7846_unlock(void)
{
GPSR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS);
spin_unlock(&corgi_ssp_lock);
}
void corgi_ssp_ads7846_put(ulong data)
{
ssp_write_word(&corgi_ssp_dev,data);
}
unsigned long corgi_ssp_ads7846_get(void)
{
return ssp_read_word(&corgi_ssp_dev);
}
EXPORT_SYMBOL(corgi_ssp_ads7846_putget);
EXPORT_SYMBOL(corgi_ssp_ads7846_lock);
EXPORT_SYMBOL(corgi_ssp_ads7846_unlock);
EXPORT_SYMBOL(corgi_ssp_ads7846_put);
EXPORT_SYMBOL(corgi_ssp_ads7846_get);
/*
* LCD/Backlight Routines
*/
unsigned long corgi_ssp_dac_put(ulong data)
{
unsigned long flag;
spin_lock_irqsave(&corgi_ssp_lock, flag);
GPCR0 = GPIO_bit(CORGI_GPIO_LCDCON_CS);
ssp_disable(&corgi_ssp_dev);
ssp_config(&corgi_ssp_dev, (SSCR0_Motorola | (SSCR0_DSS & 0x07 )), SSCR1_SPH, 0, SSCR0_SerClkDiv(76));
ssp_enable(&corgi_ssp_dev);
ssp_write_word(&corgi_ssp_dev,data);
/* Read null data back from device to prevent SSP overflow */
ssp_read_word(&corgi_ssp_dev);
ssp_disable(&corgi_ssp_dev);
ssp_config(&corgi_ssp_dev, (SSCR0_National | (SSCR0_DSS & 0x0b )), 0, 0, SSCR0_SerClkDiv(2));
ssp_enable(&corgi_ssp_dev);
GPSR0 = GPIO_bit(CORGI_GPIO_LCDCON_CS);
spin_unlock_irqrestore(&corgi_ssp_lock, flag);
return 0;
}
void corgi_ssp_lcdtg_send(u8 adrs, u8 data)
{
corgi_ssp_dac_put(((adrs & 0x07) << 5) | (data & 0x1f));
}
void corgi_ssp_blduty_set(int duty)
{
corgi_ssp_lcdtg_send(0x02,duty);
}
EXPORT_SYMBOL(corgi_ssp_lcdtg_send);
EXPORT_SYMBOL(corgi_ssp_blduty_set);
/*
* Max1111 Routines
*/
int corgi_ssp_max1111_get(ulong data)
{
unsigned long flag;
int voltage,voltage1,voltage2;
spin_lock_irqsave(&corgi_ssp_lock, flag);
GPCR0 = GPIO_bit(CORGI_GPIO_MAX1111_CS);
ssp_disable(&corgi_ssp_dev);
ssp_config(&corgi_ssp_dev, (SSCR0_Motorola | (SSCR0_DSS & 0x07 )), 0, 0, SSCR0_SerClkDiv(8));
ssp_enable(&corgi_ssp_dev);
udelay(1);
/* TB1/RB1 */
ssp_write_word(&corgi_ssp_dev,data);
ssp_read_word(&corgi_ssp_dev); /* null read */
/* TB12/RB2 */
ssp_write_word(&corgi_ssp_dev,0);
voltage1=ssp_read_word(&corgi_ssp_dev);
/* TB13/RB3*/
ssp_write_word(&corgi_ssp_dev,0);
voltage2=ssp_read_word(&corgi_ssp_dev);
ssp_disable(&corgi_ssp_dev);
ssp_config(&corgi_ssp_dev, (SSCR0_National | (SSCR0_DSS & 0x0b )), 0, 0, SSCR0_SerClkDiv(2));
ssp_enable(&corgi_ssp_dev);
GPSR0 = GPIO_bit(CORGI_GPIO_MAX1111_CS);
spin_unlock_irqrestore(&corgi_ssp_lock, flag);
if (voltage1 & 0xc0 || voltage2 & 0x3f)
voltage = -1;
else
voltage = ((voltage1 << 2) & 0xfc) | ((voltage2 >> 6) & 0x03);
return voltage;
}
EXPORT_SYMBOL(corgi_ssp_max1111_get);
/*
* Support Routines
*/
int __init corgi_ssp_probe(struct device *dev)
{
int ret;
/* Chip Select - Disable All */
GPDR0 |= GPIO_bit(CORGI_GPIO_LCDCON_CS); /* output */
GPSR0 = GPIO_bit(CORGI_GPIO_LCDCON_CS); /* High - Disable LCD Control/Timing Gen */
GPDR0 |= GPIO_bit(CORGI_GPIO_MAX1111_CS); /* output */
GPSR0 = GPIO_bit(CORGI_GPIO_MAX1111_CS); /* High - Disable MAX1111*/
GPDR0 |= GPIO_bit(CORGI_GPIO_ADS7846_CS); /* output */
GPSR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS); /* High - Disable ADS7846*/
ret=ssp_init(&corgi_ssp_dev,1);
if (ret)
printk(KERN_ERR "Unable to register SSP handler!\n");
else {
ssp_disable(&corgi_ssp_dev);
ssp_config(&corgi_ssp_dev, (SSCR0_National | (SSCR0_DSS & 0x0b )), 0, 0, SSCR0_SerClkDiv(2));
ssp_enable(&corgi_ssp_dev);
}
return ret;
}
static int corgi_ssp_remove(struct device *dev)
{
ssp_exit(&corgi_ssp_dev);
return 0;
}
static int corgi_ssp_suspend(struct device *dev, pm_message_t state, u32 level)
{
if (level == SUSPEND_POWER_DOWN) {
ssp_flush(&corgi_ssp_dev);
ssp_save_state(&corgi_ssp_dev,&corgi_ssp_state);
}
return 0;
}
static int corgi_ssp_resume(struct device *dev, u32 level)
{
if (level == RESUME_POWER_ON) {
GPSR0 = GPIO_bit(CORGI_GPIO_LCDCON_CS); /* High - Disable LCD Control/Timing Gen */
GPSR0 = GPIO_bit(CORGI_GPIO_MAX1111_CS); /* High - Disable MAX1111*/
GPSR0 = GPIO_bit(CORGI_GPIO_ADS7846_CS); /* High - Disable ADS7846*/
ssp_restore_state(&corgi_ssp_dev,&corgi_ssp_state);
ssp_enable(&corgi_ssp_dev);
}
return 0;
}
static struct device_driver corgissp_driver = {
.name = "corgi-ssp",
.bus = &platform_bus_type,
.probe = corgi_ssp_probe,
.remove = corgi_ssp_remove,
.suspend = corgi_ssp_suspend,
.resume = corgi_ssp_resume,
};
int __init corgi_ssp_init(void)
{
return driver_register(&corgissp_driver);
}
arch_initcall(corgi_ssp_init);
