--- /dev/null
+/*
+ * Mainly by David Woodhouse, somewhat modified by Jordan Crouse
+ *
+ * Copyright © 2006-2007 Red Hat, Inc.
+ * Copyright © 2006-2007 Advanced Micro Devices, Inc.
+ * Copyright © 2009 VIA Technology, Inc.
+ * Copyright (c) 2010 Andres Salomon <dilinger@queued.net>
+ *
+ * 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/console.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/backlight.h>
+#include <linux/device.h>
+#include <linux/notifier.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);
+
+struct dcon_platform_data {
+ int (*init)(void);
+ void (*bus_stabilize_wiggle)(void);
+ void (*set_dconload)(int);
+ u8 (*read_status)(void);
+};
+
+static struct dcon_platform_data *pdata;
+
+/* 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;
+
+static struct fb_info *fbinfo;
+
+/* set this to 1 while controlling fb blank state from this driver */
+static int ignore_fb_events = 0;
+
+/* 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 struct timespec dcon_irq_time;
+static struct timespec dcon_load_time;
+
+static DECLARE_WAIT_QUEUE_HEAD(dcon_wait_queue);
+
+static unsigned short normal_i2c[] = { 0x0d, I2C_CLIENT_END };
+
+#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 ==== */
+
+static int dcon_hw_init(struct i2c_client *client, int is_init)
+{
+ uint16_t ver;
+ int rc = 0;
+
+ 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 err;
+ }
+
+ if (is_init) {
+ printk(KERN_INFO "olpc-dcon: Discovered DCON version %x\n",
+ ver & 0xFF);
+ if ((rc = pdata->init()) != 0) {
+ printk(KERN_ERR "olpc-dcon: Unable to init.\n");
+ goto err;
+ }
+ }
+
+ 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);
+ }
+ else if (!noinit) {
+ /* SDRAM setup/hold time */
+ i2c_smbus_write_word_data(client, 0x3a, 0xc040);
+ i2c_smbus_write_word_data(client, 0x41, 0x0000);
+ i2c_smbus_write_word_data(client, 0x41, 0x0101);
+ i2c_smbus_write_word_data(client, 0x42, 0x0101);
+ }
+
+ /* Colour swizzle, AA, no passthrough, backlight */
+ if (is_init) {
+ 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);
+
+err:
+ return rc;
+}
+
+/*
+ * The smbus doesn't always come back due to what is believed to be
+ * hardware (power rail) bugs. For older models where this is known to
+ * occur, our solution is to attempt to wait for the bus to stabilize;
+ * if it doesn't happen, cut power to the dcon, repower it, and wait
+ * for the bus to stabilize. Rinse, repeat until we have a working
+ * smbus. For newer models, we simply BUG(); we want to know if this
+ * still happens despite the power fixes that have been made!
+ */
+static int dcon_bus_stabilize(struct i2c_client *client, int is_powered_down)
+{
+ unsigned long timeout;
+ int x;
+
+power_up:
+ if (is_powered_down) {
+ x = 1;
+ if ((x = olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0))) {
+ printk(KERN_WARNING "olpc-dcon: unable to force dcon "
+ "to power up: %d!\n", x);
+ return x;
+ }
+ msleep(10); /* we'll be conservative */
+ }
+
+ pdata->bus_stabilize_wiggle();
+
+ for (x = -1, timeout = 50; timeout && x < 0; timeout--) {
+ msleep(1);
+ x = dcon_read(DCON_REG_ID);
+ }
+ if (x < 0) {
+ printk(KERN_ERR "olpc-dcon: unable to stabilize dcon's "
+ "smbus, reasserting power and praying.\n");
+ BUG_ON(olpc_board_at_least(olpc_board(0xc2)));
+ x = 0;
+ olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0);
+ msleep(100);
+ is_powered_down = 1;
+ goto power_up; /* argh, stupid hardware.. */
+ }
+
+ if (is_powered_down)
+ return dcon_hw_init(client, 0);
+ return 0;
+}
+
+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_hw(int level)
+{
+ 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);
+ }
+}
+
+static void dcon_set_backlight(int level)
+{
+ if (dcon_client == NULL)
+ return;
+
+ if (bl_val == (level & 0x0F))
+ return;
+
+ dcon_set_backlight_hw(level);
+}
+
+/* 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)
+{
+ int x;
+
+ /* Turn off the backlight and put the DCON to sleep */
+
+ if (state == dcon_sleep_val)
+ return;
+
+ if (!olpc_board_at_least(olpc_board(0xc2)))
+ return;
+
+ if (state == DCON_SLEEP) {
+ x = 0;
+ if ((x = olpc_ec_cmd(0x26, (unsigned char *) &x, 1, NULL, 0)))
+ printk(KERN_WARNING "olpc-dcon: unable to force dcon "
+ "to power down: %d!\n", x);
+ else
+ dcon_sleep_val = state;
+ }
+ else {
+ /* Only re-enable the backlight if the backlight value is set */
+ if (bl_val != 0)
+ dcon_disp_mode |= MODE_BL_ENABLE;
+
+ if ((x=dcon_bus_stabilize(dcon_client, 1)))
+ printk(KERN_WARNING "olpc-dcon: unable to reinit dcon"
+ " hardware: %d!\n", x);
+ else
+ dcon_sleep_val = state;
+
+ /* Restore backlight */
+ dcon_set_backlight_hw(bl_val);
+ }
+
+ /* We should turn off some stuff in the framebuffer - but what? */
+}
+
+/* the DCON seems to get confused if we change DCONLOAD too
+ * frequently -- i.e., approximately faster than frame time.
+ * normally we don't change it this fast, so in general we won't
+ * delay here.
+ */
+void dcon_load_holdoff(void)
+{
+ struct timespec delta_t, now;
+ while(1) {
+ getnstimeofday(&now);
+ delta_t = timespec_sub(now, dcon_load_time);
+ if (delta_t.tv_sec != 0 ||
+ delta_t.tv_nsec > NSEC_PER_MSEC * 20) {
+ break;
+ }
+ mdelay(4);
+ }
+}
+/* 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_load_holdoff();
+
+ dcon_switched = 0;
+
+ switch (source) {
+ case DCON_SOURCE_CPU:
+ printk("dcon_source_switch to CPU\n");
+ /* 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");
+
+ /* 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");
+
+ /*
+ * Ideally we'd like to disable interrupts here so that the
+ * fb unblanking and DCON turn on happen at a known time value;
+ * however, we can't do that right now with fb_blank
+ * messing with semaphores.
+ *
+ * For now, we just hope..
+ */
+ console_lock();
+ ignore_fb_events = 1;
+ if (fb_blank(fbinfo, FB_BLANK_UNBLANK)) {
+ ignore_fb_events = 0;
+ console_unlock();
+ printk(KERN_ERR "olpc-dcon: Failed to enter CPU mode\n");
+ dcon_pending = DCON_SOURCE_DCON;
+ return;
+ }
+ ignore_fb_events = 0;
+ console_unlock();
+
+ /* And turn off the DCON */
+ pdata->set_dconload(1);
+ getnstimeofday(&dcon_load_time);
+
+ printk(KERN_INFO "olpc-dcon: The CPU has control\n");
+ break;
+ case DCON_SOURCE_DCON:
+ {
+ int t;
+ struct timespec delta_t;
+
+ printk("dcon_source_switch to DCON\n");
+
+ add_wait_queue(&dcon_wait_queue, &wait);
+ set_current_state(TASK_UNINTERRUPTIBLE);
+
+ /* Clear DCONLOAD - this implies that the DCON is in control */
+ pdata->set_dconload(0);
+ getnstimeofday(&dcon_load_time);
+
+ 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");
+ } else {
+ /* sometimes the DCON doesn't follow its own rules,
+ * and doesn't wait for two vsync pulses before
+ * ack'ing the frame load with an IRQ. the result
+ * is that the display shows the *previously*
+ * loaded frame. we can detect this by looking at
+ * the time between asserting DCONLOAD and the IRQ --
+ * if it's less than 20msec, then the DCON couldn't
+ * have seen two VSYNC pulses. in that case we
+ * deassert and reassert, and hope for the best.
+ * see http://dev.laptop.org/ticket/9664
+ */
+ delta_t = timespec_sub(dcon_irq_time, dcon_load_time);
+ if (dcon_switched && delta_t.tv_sec == 0 &&
+ delta_t.tv_nsec < NSEC_PER_MSEC * 20) {
+ printk(KERN_ERR "olpc-dcon: missed loading, retrying\n");
+ pdata->set_dconload(1);
+ mdelay(41);
+ pdata->set_dconload(0);
+ getnstimeofday(&dcon_load_time);
+ mdelay(41);
+ }
+ }
+
+ console_lock();
+ ignore_fb_events = 1;
+ if (fb_blank(fbinfo, FB_BLANK_POWERDOWN))
+ printk(KERN_ERR "olpc-dcon: couldn't blank fb!\n");
+ ignore_fb_events = 0;
+ console_unlock();
+
+ 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 void dcon_set_source(int arg)
+{
+ if (dcon_pending == arg)
+ return;
+
+ dcon_pending = arg;
+
+ if ((dcon_source != arg) && !work_pending(&dcon_work))
+ schedule_work(&dcon_work);
+}
+
+static void dcon_set_source_sync(int arg)
+{
+ dcon_set_source(arg);
+ flush_scheduled_work();
+}
+
+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 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 dcon_freeze_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ int output;
+
+ if (_strtoul(buf, count, &output))
+ return -EINVAL;
+
+ printk("dcon_freeze_store: %d\n", output);
+
+ switch (output) {
+ case 0:
+ dcon_set_source(DCON_SOURCE_CPU);
+ break;
+ case 1:
+ dcon_set_source_sync(DCON_SOURCE_DCON);
+ break;
+ case 2: // normally unused
+ dcon_set_source(DCON_SOURCE_DCON);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+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(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 const struct backlight_ops dcon_bl_ops = {
+ .get_brightness = dconbl_get,
+ .update_status = dconbl_set
+};
+
+
+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 struct notifier_block dcon_nb = {
+ .notifier_call = dcon_reboot_notify,
+ .priority = -1,
+};
+
+static int unfreeze_on_panic(struct notifier_block *nb, unsigned long e, void *p)
+{
+ pdata->set_dconload(1);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block dcon_panic_nb = {
+ .notifier_call = unfreeze_on_panic,
+};
+
+/*
+ * When the framebuffer sleeps due to external sources (e.g. user idle), power
+ * down the DCON as well. Power it back up when the fb comes back to life.
+ */
+static int fb_notifier_callback(struct notifier_block *self, unsigned long event, void *data)
+{
+ struct fb_event *evdata = data;
+ int *blank = (int *) evdata->data;
+ if (((event != FB_EVENT_BLANK) && (event != FB_EVENT_CONBLANK)) ||
+ ignore_fb_events)
+ return 0;
+ dcon_sleep((*blank) ? DCON_SLEEP : DCON_ACTIVE);
+ return 0;
+}
+
+static struct notifier_block fb_nb = {
+ .notifier_call = fb_notifier_callback,
+};
+
+static int dcon_detect(struct i2c_client *client, struct i2c_board_info *info)
+{
+ strlcpy(info->type, "olpc_dcon", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ int rc, i;
+
+ if (num_registered_fb >= 1)
+ fbinfo = registered_fb[0];
+
+ rc = dcon_hw_init(client, 1);
+ if (rc)
+ goto einit;
+
+ /* Add the DCON device */
+
+ dcon_device = platform_device_alloc("dcon", -1);
+
+ if (dcon_device == NULL) {
+ printk("dcon: Unable to create the DCON device\n");
+ rc = -ENOMEM;
+ goto eirq;
+ }
+ /* Place holder...*/
+ i2c_set_clientdata(client, dcon_device);
+
+ if ((rc = platform_device_add(dcon_device))) {
+ printk("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, NULL);
+
+ if (IS_ERR(dcon_bl_dev)) {
+ printk("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);
+ atomic_notifier_chain_register(&panic_notifier_list, &dcon_panic_nb);
+ fb_register_client(&fb_nb);
+
+ return 0;
+
+ edev:
+ platform_device_unregister(dcon_device);
+ dcon_device = NULL;
+ eirq:
+ free_irq(DCON_IRQ, &dcon_driver);
+ einit:
+ return rc;
+}
+
+static int dcon_remove(struct i2c_client *client)
+{
+ dcon_client = NULL;
+
+ fb_unregister_client(&fb_nb);
+ unregister_reboot_notifier(&dcon_nb);
+ atomic_notifier_chain_unregister(&panic_notifier_list, &dcon_panic_nb);
+
+ free_irq(DCON_IRQ, &dcon_driver);
+
+ 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 0;
+}
+
+#ifdef CONFIG_PM
+static int dcon_suspend(struct i2c_client *client, pm_message_t state)
+{
+ if (dcon_sleep_val == DCON_ACTIVE) {
+ /* Set up the DCON to have the source */
+ dcon_set_source_sync(DCON_SOURCE_DCON);
+ }
+
+ return 0;
+}
+
+static int dcon_resume(struct i2c_client *client)
+{
+ if (dcon_sleep_val == DCON_ACTIVE) {
+ dcon_bus_stabilize(client, 0);
+ dcon_set_source(DCON_SOURCE_CPU);
+ }
+
+ return 0;
+}
+
+#endif
+
+
+static irqreturn_t dcon_interrupt(int irq, void *id)
+{
+ int status = pdata->read_status();
+
+ if (status == -1)
+ return IRQ_NONE;
+
+ 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;
+ getnstimeofday(&dcon_irq_time);
+ wake_up(&dcon_wait_queue);
+ break;
+
+ case 0:
+ /* workaround resume case: the DCON (on 1.5) doesn't
+ * ever assert status 0x01 when switching to CPU mode
+ * during resume. this is because DCONLOAD is de-asserted
+ * _immediately_ upon exiting S3, so the actual release
+ * of the DCON happened long before this point.
+ * see http://dev.laptop.org/ticket/9869
+ */
+ if (dcon_source != dcon_pending && !dcon_switched) {
+ dcon_switched = 1;
+ getnstimeofday(&dcon_irq_time);
+ wake_up(&dcon_wait_queue);
+ printk(KERN_DEBUG "olpc-dcon: switching w/ status 0/0\n");
+ } else {
+ printk(KERN_DEBUG "olpc-dcon: scanline interrupt w/CPU\n");
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static struct i2c_device_id dcon_idtable[] = {
+ { "olpc_dcon", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, dcon_idtable);
+
+static struct i2c_driver dcon_driver = {
+ .driver = {
+ .name = "olpc_dcon",
+ },
+ .class = I2C_CLASS_DDC | I2C_CLASS_HWMON,
+ .id_table = dcon_idtable,
+ .probe = dcon_probe,
+ .remove = __devexit_p(dcon_remove),
+ .detect = dcon_detect,
+ .address_list = normal_i2c,
+#ifdef CONFIG_PM
+ .suspend = dcon_suspend,
+ .resume = dcon_resume,
+#endif
+};
+
+#include "olpc_dcon_xo_1.c"
+
+static int __init olpc_dcon_init(void)
+{
+ pdata = &dcon_pdata_xo_1;
+
+ 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");
projects / mv-sheeva.git / blobdiff