openwrtv4/target/linux/olpc/files/drivers/video/olpc_dcon.c
John Crispin 42fc624cba cleaning up olpc patch 1
SVN-Revision: 10060
2007-12-30 17:38:08 +00:00

824 lines
19 KiB
C

/*
* Mainly by David Woodhouse, somewhat modified by Jordan Crouse
*
* Copyright © 2006-2007 Red Hat, Inc.
* Copyright © 2006-2007 Advanced Micro Devices, Inc.
*
* This program is free software. You can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/i2c-id.h>
#include <linux/pci.h>
#include <linux/vt_kern.h>
#include <linux/pci_ids.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/backlight.h>
#include <linux/device.h>
#include <asm/uaccess.h>
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <asm/tsc.h>
#include <asm/olpc.h>
#include "olpc_dcon.h"
/* Module definitions */
static int resumeline = 898;
module_param(resumeline, int, 0444);
static int noinit;
module_param(noinit, int, 0444);
/* Default off since it doesn't work on DCON ASIC in B-test OLPC board */
static int useaa = 1;
module_param(useaa, int, 0444);
/* I2C structures */
static struct i2c_driver dcon_driver;
static struct i2c_client *dcon_client;
/* Platform devices */
static struct platform_device *dcon_device;
/* Backlight device */
static struct backlight_device *dcon_bl_dev;
/* Base address of the GPIO registers */
static unsigned long gpio_base;
static struct fb_info *fbinfo;
/* Current source, initialized at probe time */
static int dcon_source;
/* Desired source */
static int dcon_pending;
/* Current output type */
static int dcon_output = DCON_OUTPUT_COLOR;
/* Current sleep status (not yet implemented) */
static int dcon_sleep_val = DCON_ACTIVE;
/* Shadow register for the DCON_REG_MODE register */
static unsigned short dcon_disp_mode;
/* Variables used during switches */
static int dcon_switched;
static DECLARE_WAIT_QUEUE_HEAD(dcon_wait_queue);
static unsigned short normal_i2c[] = { 0x0D, I2C_CLIENT_END };
I2C_CLIENT_INSMOD;
#define dcon_write(reg,val) i2c_smbus_write_word_data(dcon_client,reg,val)
#define dcon_read(reg) i2c_smbus_read_word_data(dcon_client,reg)
/* The current backlight value - this saves us some smbus traffic */
static int bl_val = -1;
/* ===== API functions - these are called by a variety of users ==== */
/* Backlight notes - turning off the backlight enable bit in the DCON
* doesn't save us any power over just pushing the BL to zero, so we
* don't use that bit in this code.
*/
static int dcon_get_backlight(void)
{
if (dcon_client == NULL)
return 0;
if (bl_val == -1)
bl_val = dcon_read(DCON_REG_BRIGHT) & 0x0F;
return bl_val;
}
static void dcon_set_backlight(int level)
{
if (dcon_client == NULL)
return;
if (bl_val == (level & 0x0F))
return;
bl_val = level & 0x0F;
dcon_write(DCON_REG_BRIGHT, bl_val);
/* Purposely turn off the backlight when we go to level 0 */
if (bl_val == 0) {
dcon_disp_mode &= ~MODE_BL_ENABLE;
dcon_write(DCON_REG_MODE, dcon_disp_mode);
}
else if (!(dcon_disp_mode & MODE_BL_ENABLE)) {
dcon_disp_mode |= MODE_BL_ENABLE;
dcon_write(DCON_REG_MODE, dcon_disp_mode);
}
}
/* Set the output type to either color or mono */
static int dcon_set_output(int arg)
{
if (dcon_output == arg)
return 0;
dcon_output = arg;
if (arg == DCON_OUTPUT_MONO) {
dcon_disp_mode &= ~(MODE_CSWIZZLE | MODE_COL_AA);
dcon_disp_mode |= MODE_MONO_LUMA;
}
else {
dcon_disp_mode &= ~(MODE_MONO_LUMA);
dcon_disp_mode |= MODE_CSWIZZLE;
if (useaa)
dcon_disp_mode |= MODE_COL_AA;
}
dcon_write(DCON_REG_MODE, dcon_disp_mode);
return 0;
}
/* For now, this will be really stupid - we need to address how
* DCONLOAD works in a sleep and account for it accordingly
*/
static void dcon_sleep(int state)
{
/* Turn off the backlight and put the DCON to sleep */
if (state == dcon_sleep_val)
return;
if (state == DCON_SLEEP) {
dcon_disp_mode &= ~MODE_BL_ENABLE;
dcon_disp_mode |= MODE_SLEEP;
}
else {
/* Only re-enable the backlight if the backlight value is set */
if (bl_val != 0)
dcon_disp_mode |= MODE_BL_ENABLE;
dcon_disp_mode &= ~MODE_SLEEP;
}
dcon_sleep_val = state;
dcon_write(DCON_REG_MODE, dcon_disp_mode);
/* We should turn off some stuff in the framebuffer - but what? */
}
/* Set the source of the display (CPU or DCON) */
static void dcon_source_switch(struct work_struct *work)
{
DECLARE_WAITQUEUE(wait, current);
int source = dcon_pending;
if (dcon_source == source)
return;
dcon_switched = 0;
switch (source) {
case DCON_SOURCE_CPU:
/* Enable the scanline interrupt bit */
if (dcon_write(DCON_REG_MODE, dcon_disp_mode | MODE_SCAN_INT))
printk(KERN_ERR "olpc-dcon: couldn't enable scanline interrupt!\n");
else {
/* Wait up to one second for the scanline interrupt */
wait_event_timeout(dcon_wait_queue, dcon_switched == 1, HZ);
}
if (!dcon_switched)
printk(KERN_ERR "olpc-dcon: Timeout entering CPU mode; expect a screen glitch.\n");
/*
* Ideally we'd like to disable interrupts here so that the
* fb_powerup and DCON turn on happen at a known time value;
* however, we can't do that right now with fb_set_suspend
* messing with semaphores.
*
* For now, we just hope..
*/
if (fb_powerup(fbinfo)) {
printk(KERN_ERR "olpc-dcon: Failed to enter CPU mode\n");
dcon_pending = DCON_SOURCE_DCON;
return;
}
/* And turn off the DCON */
outl(1<<11, gpio_base + GPIOx_OUT_VAL);
/* Turn off the scanline interrupt */
if (dcon_write(DCON_REG_MODE, dcon_disp_mode))
printk(KERN_ERR "olpc-dcon: couldn't disable scanline interrupt!\n");
printk(KERN_INFO "olpc-dcon: The CPU has control\n");
break;
case DCON_SOURCE_DCON:
{
int t;
add_wait_queue(&dcon_wait_queue, &wait);
set_current_state(TASK_UNINTERRUPTIBLE);
/* Clear GPIO11 (DCONLOAD) - this implies that the DCON is in
control */
outl(1 << (11 + 16), gpio_base + GPIOx_OUT_VAL);
t = schedule_timeout(HZ/2);
remove_wait_queue(&dcon_wait_queue, &wait);
set_current_state(TASK_RUNNING);
if (!dcon_switched)
printk(KERN_ERR "olpc-dcon: Timeout entering DCON mode; expect a screen glitch.\n");
/* Turn off the graphics engine completely */
fb_powerdown(fbinfo);
printk(KERN_INFO "olpc-dcon: The DCON has control\n");
break;
}
default:
BUG();
}
dcon_source = source;
}
static DECLARE_WORK(dcon_work, dcon_source_switch);
static int dcon_set_source(int arg)
{
if (arg != DCON_SOURCE_CPU && arg != DCON_SOURCE_DCON)
return -EINVAL;
if (dcon_pending == arg)
return 0;
dcon_pending = arg;
if ((dcon_source != arg) && !work_pending(&dcon_work))
schedule_work(&dcon_work);
return 0;
}
static int dcon_set_source_sync(int arg)
{
int ret = dcon_set_source(arg);
if (!ret)
flush_scheduled_work();
return ret;
}
static int dconbl_set(struct backlight_device *dev) {
int level = dev->props.brightness;
if (dev->props.power != FB_BLANK_UNBLANK)
level = 0;
dcon_set_backlight(level);
return 0;
}
static int dconbl_get(struct backlight_device *dev) {
return dcon_get_backlight();
}
static ssize_t dcon_mode_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%4.4X\n", dcon_disp_mode);
}
static ssize_t dcon_sleep_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", dcon_sleep_val);
}
static ssize_t /* __deprecated */ dcon_source_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
printk(KERN_WARNING "olpc-dcon: using deprecated sysfs 'source' interface; use 'freeze' instead!\n");
return sprintf(buf, "%d\n", dcon_source);
}
static ssize_t dcon_freeze_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", dcon_source == DCON_SOURCE_DCON ? 1 : 0);
}
static ssize_t dcon_output_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", dcon_output);
}
static ssize_t dcon_resumeline_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", resumeline);
}
static int _strtoul(const char *buf, int len, unsigned int *val)
{
char *endp;
unsigned int output = simple_strtoul(buf, &endp, 0);
int size = endp - buf;
if (*endp && isspace(*endp))
size++;
if (size != len)
return -EINVAL;
*val = output;
return 0;
}
static ssize_t dcon_output_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int output;
int rc = -EINVAL;
if (_strtoul(buf, count, &output))
return -EINVAL;
if (output == DCON_OUTPUT_COLOR || output == DCON_OUTPUT_MONO) {
dcon_set_output(output);
rc = count;
}
return rc;
}
static ssize_t /* __deprecated */ dcon_source_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int output;
int rc = -EINVAL;
printk(KERN_WARNING "olpc-dcon: using deprecated sysfs 'source' interface; use 'freeze' instead!\n");
if (_strtoul(buf, count, &output))
return -EINVAL;
dcon_set_source(output);
rc = count;
return rc;
}
static ssize_t dcon_freeze_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int output;
int rc = -EINVAL;
if (_strtoul(buf, count, &output))
return rc;
dcon_set_source(output ? DCON_SOURCE_DCON : DCON_SOURCE_CPU);
rc = count;
return rc;
}
static ssize_t dcon_resumeline_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int rl;
int rc = -EINVAL;
if (_strtoul(buf, count, &rl))
return rc;
resumeline = rl;
dcon_write(DCON_REG_SCAN_INT, resumeline);
rc = count;
return rc;
}
static ssize_t dcon_sleep_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
int output;
if (_strtoul(buf, count, &output))
return -EINVAL;
dcon_sleep(output ? DCON_SLEEP : DCON_ACTIVE);
return count;
}
static struct device_attribute dcon_device_files[] = {
__ATTR(mode, 0444, dcon_mode_show, NULL),
__ATTR(sleep, 0644, dcon_sleep_show, dcon_sleep_store),
__ATTR(source, 0644, dcon_source_show, dcon_source_store),
__ATTR(freeze, 0644, dcon_freeze_show, dcon_freeze_store),
__ATTR(output, 0644, dcon_output_show, dcon_output_store),
__ATTR(resumeline, 0644, dcon_resumeline_show, dcon_resumeline_store),
};
static struct backlight_ops dcon_bl_ops = {
.get_brightness = dconbl_get,
.update_status = dconbl_set
};
/* List of GPIOs that we care about:
(in) GPIO12 -- DCONBLNK
(in) GPIO[56] -- DCONSTAT[01]
(out) GPIO11 -- DCONLOAD
*/
#define IN_GPIOS ((1<<5) | (1<<6) | (1<<7) | (1<<12))
#define OUT_GPIOS (1<<11)
static irqreturn_t dcon_interrupt(int, void *);
static int dcon_request_irq(void)
{
unsigned long lo, hi;
unsigned char lob;
rdmsr(MSR_LBAR_GPIO, lo, hi);
/* Check the mask and whether GPIO is enabled (sanity check) */
if (hi != 0x0000f001) {
printk(KERN_ERR "GPIO not enabled -- cannot use DCON\n");
return -ENODEV;
}
/* Mask off the IO base address */
gpio_base = lo & 0x0000ff00;
/* Turn off the event enable for GPIO7 just to be safe */
outl(1 << (16+7), gpio_base + GPIOx_EVNT_EN);
/* Set the directions for the GPIO pins */
outl(OUT_GPIOS | (IN_GPIOS << 16), gpio_base + GPIOx_OUT_EN);
outl(IN_GPIOS | (OUT_GPIOS << 16), gpio_base + GPIOx_IN_EN);
/* Set up the interrupt mappings */
/* Set the IRQ to pair 2 */
geode_gpio_event_irq(OLPC_GPIO_DCON_IRQ, 2);
/* Enable group 2 to trigger the DCON interrupt */
geode_gpio_set_irq(2, DCON_IRQ);
/* Select edge level for interrupt (in PIC) */
lob = inb(0x4d0);
lob &= ~(1 << DCON_IRQ);
outb(lob, 0x4d0);
/* Register the interupt handler */
if (request_irq(DCON_IRQ, &dcon_interrupt, 0, "DCON", &dcon_driver))
return -EIO;
/* Clear INV_EN for GPIO7 (DCONIRQ) */
outl((1<<(16+7)), gpio_base + GPIOx_INV_EN);
/* Enable filter for GPIO12 (DCONBLANK) */
outl(1<<(12), gpio_base + GPIOx_IN_FLTR_EN);
/* Disable filter for GPIO7 */
outl(1<<(16+7), gpio_base + GPIOx_IN_FLTR_EN);
/* Disable event counter for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
outl(1<<(16+7), gpio_base + GPIOx_EVNTCNT_EN);
outl(1<<(16+12), gpio_base + GPIOx_EVNTCNT_EN);
/* Add GPIO12 to the Filter Event Pair #7 */
outb(12, gpio_base + GPIO_FE7_SEL);
/* Turn off negative Edge Enable for GPIO12 */
outl(1<<(16+12), gpio_base + GPIOx_NEGEDGE_EN);
/* Enable negative Edge Enable for GPIO7 */
outl(1<<7, gpio_base + GPIOx_NEGEDGE_EN);
/* Zero the filter amount for Filter Event Pair #7 */
outw(0, gpio_base + GPIO_FLT7_AMNT);
/* Clear the negative edge status for GPIO7 and GPIO12 */
outl((1<<7) | (1<<12), gpio_base+0x4c);
/* FIXME: Clear the posiitive status as well, just to be sure */
outl((1<<7) | (1<<12), gpio_base+0x48);
/* Enable events for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
outl((1<<(7))|(1<<12), gpio_base + GPIOx_EVNT_EN);
/* Determine the current state by reading the GPIO bit */
/* Earlier stages of the boot process have established the state */
dcon_source = inl(gpio_base + GPIOx_OUT_VAL) & (1<<11)
? DCON_SOURCE_CPU
: DCON_SOURCE_DCON;
dcon_pending = dcon_source;
return 0;
}
static int dcon_reboot_notify(struct notifier_block *nb, unsigned long foo, void *bar)
{
if (dcon_client == NULL)
return 0;
/* Turn off the DCON. Entirely. */
dcon_write(DCON_REG_MODE, 0x39);
dcon_write(DCON_REG_MODE, 0x32);
return 0;
}
static int dcon_conswitch_notify(struct notifier_block *nb,
unsigned long mode, void *dummy)
{
if (mode == CONSOLE_EVENT_SWITCH_TEXT)
dcon_sleep(DCON_ACTIVE);
return 0;
}
static struct notifier_block dcon_nb = {
.notifier_call = dcon_reboot_notify,
.priority = -1,
};
static struct notifier_block dcon_console_nb = {
.notifier_call = dcon_conswitch_notify,
.priority = -1,
};
static int dcon_probe(struct i2c_adapter *adap, int addr, int kind)
{
struct i2c_client *client;
uint16_t ver;
int rc, i;
if (!olpc_has_dcon()) {
printk("olpc-dcon: No DCON is attached.\n");
return -ENODEV;
}
if (num_registered_fb >= 1)
fbinfo = registered_fb[0];
if (adap->id != I2C_HW_SMBUS_SCX200) {
printk(KERN_ERR "olpc-dcon: Invalid I2C bus (%d not %d)\n",
adap->id, I2C_HW_SMBUS_SCX200);
return -ENXIO;
}
client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
if (client == NULL)
return -ENOMEM;
strncpy(client->name, "OLPC-DCON", I2C_NAME_SIZE);
client->addr = addr;
client->adapter = adap;
client->driver = &dcon_driver;
if ((rc = i2c_attach_client(client)) != 0) {
printk(KERN_ERR "olpc-dcon: Unable to attach the I2C client.\n");
goto eclient;
}
ver = i2c_smbus_read_word_data(client, DCON_REG_ID);
if ((ver >> 8) != 0xDC) {
printk(KERN_ERR "olpc-dcon: DCON ID not 0xDCxx: 0x%04x instead.\n", ver);
rc = -ENXIO;
goto ei2c;
}
if ((rc = dcon_request_irq())) {
printk(KERN_ERR "olpc-dcon: Unable to grab IRQ.\n");
goto ei2c;
}
if (ver < 0xdc02 && !noinit) {
/* Initialize the DCON registers */
/* Start with work-arounds for DCON ASIC */
i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
i2c_smbus_write_word_data(client, 0x4b, 0x00cc);
i2c_smbus_write_word_data(client, 0x0b, 0x007a);
i2c_smbus_write_word_data(client, 0x36, 0x025c);
i2c_smbus_write_word_data(client, 0x37, 0x025e);
/* Initialise SDRAM */
i2c_smbus_write_word_data(client, 0x3b, 0x002b);
i2c_smbus_write_word_data(client, 0x41, 0x0101);
i2c_smbus_write_word_data(client, 0x42, 0x0101);
}
/* Colour swizzle, AA, no passthrough, backlight */
dcon_disp_mode = MODE_PASSTHRU | MODE_BL_ENABLE | MODE_CSWIZZLE;
if (useaa)
dcon_disp_mode |= MODE_COL_AA;
i2c_smbus_write_word_data(client, DCON_REG_MODE, dcon_disp_mode);
/* Set the scanline to interrupt on during resume */
i2c_smbus_write_word_data(client, DCON_REG_SCAN_INT, resumeline);
/* Add the DCON device */
dcon_device = platform_device_alloc("dcon", -1);
if (dcon_device == NULL) {
printk(KERN_ERR "dcon: Unable to create the DCON device\n");
rc = -ENOMEM;
goto eirq;
}
if ((rc = platform_device_add(dcon_device))) {
printk(KERN_ERR "dcon: Unable to add the DCON device\n");
goto edev;
}
for(i = 0; i < ARRAY_SIZE(dcon_device_files); i++)
device_create_file(&dcon_device->dev, &dcon_device_files[i]);
/* Add the backlight device for the DCON */
dcon_client = client;
dcon_bl_dev = backlight_device_register("dcon-bl", &dcon_device->dev,
NULL, &dcon_bl_ops);
if (IS_ERR(dcon_bl_dev)) {
printk(KERN_INFO "Could not register the backlight device for the DCON (%ld)\n", PTR_ERR(dcon_bl_dev));
dcon_bl_dev = NULL;
}
else {
dcon_bl_dev->props.max_brightness = 15;
dcon_bl_dev->props.power = FB_BLANK_UNBLANK;
dcon_bl_dev->props.brightness = dcon_get_backlight();
backlight_update_status(dcon_bl_dev);
}
register_reboot_notifier(&dcon_nb);
console_event_register(&dcon_console_nb);
printk(KERN_INFO "olpc-dcon: Discovered DCON version %x\n", ver & 0xFF);
return 0;
edev:
platform_device_unregister(dcon_device);
dcon_device = NULL;
eirq:
free_irq(DCON_IRQ, &dcon_driver);
ei2c:
i2c_detach_client(client);
eclient:
kfree(client);
return rc;
}
static int dcon_attach(struct i2c_adapter *adap)
{
int ret;
ret = i2c_probe(adap, &addr_data, dcon_probe);
if (dcon_client == NULL)
printk(KERN_ERR "olpc-dcon: No DCON found on SMBus\n");
return ret;
}
static int dcon_detach(struct i2c_client *client)
{
int rc;
dcon_client = NULL;
unregister_reboot_notifier(&dcon_nb);
console_event_unregister(&dcon_console_nb);
free_irq(DCON_IRQ, &dcon_driver);
if ((rc = i2c_detach_client(client)) == 0)
kfree(i2c_get_clientdata(client));
if (dcon_bl_dev != NULL)
backlight_device_unregister(dcon_bl_dev);
if (dcon_device != NULL)
platform_device_unregister(dcon_device);
cancel_work_sync(&dcon_work);
return rc;
}
#ifdef CONFIG_PM
static int dcon_suspend(struct i2c_client *client, pm_message_t state)
{
if (dcon_sleep_val != DCON_ACTIVE)
return 0;
/* Set up the DCON to have the source */
return dcon_set_source_sync(DCON_SOURCE_DCON);
}
static int dcon_resume(struct i2c_client *client)
{
int x;
if (dcon_sleep_val != DCON_ACTIVE)
return 0;
/* HACK: ensure the bus is stable */
do {
x = dcon_read(DCON_REG_ID);
} while (x < 0);
return dcon_set_source(DCON_SOURCE_CPU);
}
#endif
static irqreturn_t dcon_interrupt(int irq, void *id)
{
int status = inl(gpio_base + GPIOx_READ_BACK) >> 5;
/* Clear the negative edge status for GPIO7 */
outl(1 << 7, gpio_base + GPIOx_NEGEDGE_STS);
switch (status & 3) {
case 3:
printk(KERN_DEBUG "olpc-dcon: DCONLOAD_MISSED interrupt\n");
break;
case 2: /* switch to DCON mode */
case 1: /* switch to CPU mode */
dcon_switched = 1;
wake_up(&dcon_wait_queue);
break;
case 0:
printk(KERN_DEBUG "olpc-dcon: scanline interrupt w/CPU\n");
}
return IRQ_HANDLED;
}
static struct i2c_driver dcon_driver = {
.driver = {
.name = "OLPC-DCON",
},
.id = I2C_DRIVERID_DCON,
.attach_adapter = dcon_attach,
.detach_client = dcon_detach,
#ifdef CONFIG_PM
.suspend = dcon_suspend,
.resume = dcon_resume,
#endif
};
static int __init olpc_dcon_init(void)
{
i2c_add_driver(&dcon_driver);
return 0;
}
static void __exit olpc_dcon_exit(void)
{
i2c_del_driver(&dcon_driver);
}
module_init(olpc_dcon_init);
module_exit(olpc_dcon_exit);
MODULE_LICENSE("GPL");