corgi_ssp.c 6.1 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248
/*
 *  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);