--- /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) 2010-2011 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/fb.h>
+#include <linux/console.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/backlight.h>
+#include <linux/device.h>
+#include <linux/uaccess.h>
+#include <linux/ctype.h>
+#include <linux/reboot.h>
+#include <linux/olpc-ec.h>
+#include <asm/tsc.h>
+#include <asm/olpc.h>
+
+#include "olpc_dcon.h"
+
+/* Module definitions */
+
+static ushort resumeline = 898;
+module_param(resumeline, ushort, 0444);
+
+static struct dcon_platform_data *pdata;
+
+/* I2C structures */
+
+/* Platform devices */
+static struct platform_device *dcon_device;
+
+static unsigned short normal_i2c[] = { 0x0d, I2C_CLIENT_END };
+
+static s32 dcon_write(struct dcon_priv *dcon, u8 reg, u16 val)
+{
+ return i2c_smbus_write_word_data(dcon->client, reg, val);
+}
+
+static s32 dcon_read(struct dcon_priv *dcon, u8 reg)
+{
+ return i2c_smbus_read_word_data(dcon->client, reg);
+}
+
+/* ===== API functions - these are called by a variety of users ==== */
+
+static int dcon_hw_init(struct dcon_priv *dcon, int is_init)
+{
+ u16 ver;
+ int rc = 0;
+
+ ver = dcon_read(dcon, DCON_REG_ID);
+ if ((ver >> 8) != 0xDC) {
+ pr_err("DCON ID not 0xDCxx: 0x%04x instead.\n", ver);
+ rc = -ENXIO;
+ goto err;
+ }
+
+ if (is_init) {
+ pr_info("Discovered DCON version %x\n", ver & 0xFF);
+ rc = pdata->init(dcon);
+ if (rc != 0) {
+ pr_err("Unable to init.\n");
+ goto err;
+ }
+ }
+
+ if (ver < 0xdc02) {
+ dev_err(&dcon->client->dev,
+ "DCON v1 is unsupported, giving up..\n");
+ rc = -ENODEV;
+ goto err;
+ }
+
+ /* SDRAM setup/hold time */
+ dcon_write(dcon, 0x3a, 0xc040);
+ dcon_write(dcon, DCON_REG_MEM_OPT_A, 0x0000); /* clear option bits */
+ dcon_write(dcon, DCON_REG_MEM_OPT_A,
+ MEM_DLL_CLOCK_DELAY | MEM_POWER_DOWN);
+ dcon_write(dcon, DCON_REG_MEM_OPT_B, MEM_SOFT_RESET);
+
+ /* Colour swizzle, AA, no passthrough, backlight */
+ if (is_init) {
+ dcon->disp_mode = MODE_PASSTHRU | MODE_BL_ENABLE |
+ MODE_CSWIZZLE | MODE_COL_AA;
+ }
+ dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
+
+ /* Set the scanline to interrupt on during resume */
+ dcon_write(dcon, 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 dcon_priv *dcon, int is_powered_down)
+{
+ unsigned long timeout;
+ u8 pm;
+ int x;
+
+power_up:
+ if (is_powered_down) {
+ pm = 1;
+ x = olpc_ec_cmd(EC_DCON_POWER_MODE, &pm, 1, NULL, 0);
+ if (x) {
+ pr_warn("unable to force dcon to power up: %d!\n", x);
+ return x;
+ }
+ usleep_range(10000, 11000); /* we'll be conservative */
+ }
+
+ pdata->bus_stabilize_wiggle();
+
+ for (x = -1, timeout = 50; timeout && x < 0; timeout--) {
+ usleep_range(1000, 1100);
+ x = dcon_read(dcon, DCON_REG_ID);
+ }
+ if (x < 0) {
+ pr_err("unable to stabilize dcon's smbus, reasserting power and praying.\n");
+ BUG_ON(olpc_board_at_least(olpc_board(0xc2)));
+ pm = 0;
+ olpc_ec_cmd(EC_DCON_POWER_MODE, &pm, 1, NULL, 0);
+ msleep(100);
+ is_powered_down = 1;
+ goto power_up; /* argh, stupid hardware.. */
+ }
+
+ if (is_powered_down)
+ return dcon_hw_init(dcon, 0);
+ return 0;
+}
+
+static void dcon_set_backlight(struct dcon_priv *dcon, u8 level)
+{
+ dcon->bl_val = level;
+ dcon_write(dcon, DCON_REG_BRIGHT, dcon->bl_val);
+
+ /* Purposely turn off the backlight when we go to level 0 */
+ if (dcon->bl_val == 0) {
+ dcon->disp_mode &= ~MODE_BL_ENABLE;
+ dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
+ } else if (!(dcon->disp_mode & MODE_BL_ENABLE)) {
+ dcon->disp_mode |= MODE_BL_ENABLE;
+ dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
+ }
+}
+
+/* Set the output type to either color or mono */
+static int dcon_set_mono_mode(struct dcon_priv *dcon, bool enable_mono)
+{
+ if (dcon->mono == enable_mono)
+ return 0;
+
+ dcon->mono = enable_mono;
+
+ if (enable_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 | MODE_COL_AA;
+ }
+
+ dcon_write(dcon, 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(struct dcon_priv *dcon, bool sleep)
+{
+ int x;
+
+ /* Turn off the backlight and put the DCON to sleep */
+
+ if (dcon->asleep == sleep)
+ return;
+
+ if (!olpc_board_at_least(olpc_board(0xc2)))
+ return;
+
+ if (sleep) {
+ u8 pm = 0;
+
+ x = olpc_ec_cmd(EC_DCON_POWER_MODE, &pm, 1, NULL, 0);
+ if (x)
+ pr_warn("unable to force dcon to power down: %d!\n", x);
+ else
+ dcon->asleep = sleep;
+ } else {
+ /* Only re-enable the backlight if the backlight value is set */
+ if (dcon->bl_val != 0)
+ dcon->disp_mode |= MODE_BL_ENABLE;
+ x = dcon_bus_stabilize(dcon, 1);
+ if (x)
+ pr_warn("unable to reinit dcon hardware: %d!\n", x);
+ else
+ dcon->asleep = sleep;
+
+ /* Restore backlight */
+ dcon_set_backlight(dcon, dcon->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.
+ */
+static void dcon_load_holdoff(struct dcon_priv *dcon)
+{
+ ktime_t delta_t, now;
+
+ while (1) {
+ now = ktime_get();
+ delta_t = ktime_sub(now, dcon->load_time);
+ if (ktime_to_ns(delta_t) > NSEC_PER_MSEC * 20)
+ break;
+ mdelay(4);
+ }
+}
+
+static bool dcon_blank_fb(struct dcon_priv *dcon, bool blank)
+{
+ int err;
+
+ console_lock();
+ if (!lock_fb_info(dcon->fbinfo)) {
+ console_unlock();
+ dev_err(&dcon->client->dev, "unable to lock framebuffer\n");
+ return false;
+ }
+
+ dcon->ignore_fb_events = true;
+ err = fb_blank(dcon->fbinfo,
+ blank ? FB_BLANK_POWERDOWN : FB_BLANK_UNBLANK);
+ dcon->ignore_fb_events = false;
+ unlock_fb_info(dcon->fbinfo);
+ console_unlock();
+
+ if (err) {
+ dev_err(&dcon->client->dev, "couldn't %sblank framebuffer\n",
+ blank ? "" : "un");
+ return false;
+ }
+ return true;
+}
+
+/* Set the source of the display (CPU or DCON) */
+static void dcon_source_switch(struct work_struct *work)
+{
+ struct dcon_priv *dcon = container_of(work, struct dcon_priv,
+ switch_source);
+ int source = dcon->pending_src;
+
+ if (dcon->curr_src == source)
+ return;
+
+ dcon_load_holdoff(dcon);
+
+ dcon->switched = false;
+
+ switch (source) {
+ case DCON_SOURCE_CPU:
+ pr_info("dcon_source_switch to CPU\n");
+ /* Enable the scanline interrupt bit */
+ if (dcon_write(dcon, DCON_REG_MODE,
+ dcon->disp_mode | MODE_SCAN_INT))
+ pr_err("couldn't enable scanline interrupt!\n");
+ else
+ /* Wait up to one second for the scanline interrupt */
+ wait_event_timeout(dcon->waitq, dcon->switched, HZ);
+
+ if (!dcon->switched)
+ pr_err("Timeout entering CPU mode; expect a screen glitch.\n");
+
+ /* Turn off the scanline interrupt */
+ if (dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode))
+ pr_err("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..
+ */
+ if (!dcon_blank_fb(dcon, false)) {
+ pr_err("Failed to enter CPU mode\n");
+ dcon->pending_src = DCON_SOURCE_DCON;
+ return;
+ }
+
+ /* And turn off the DCON */
+ pdata->set_dconload(1);
+ dcon->load_time = ktime_get();
+
+ pr_info("The CPU has control\n");
+ break;
+ case DCON_SOURCE_DCON:
+ {
+ ktime_t delta_t;
+
+ pr_info("dcon_source_switch to DCON\n");
+
+ /* Clear DCONLOAD - this implies that the DCON is in control */
+ pdata->set_dconload(0);
+ dcon->load_time = ktime_get();
+
+ wait_event_timeout(dcon->waitq, dcon->switched, HZ/2);
+
+ if (!dcon->switched) {
+ pr_err("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 = ktime_sub(dcon->irq_time, dcon->load_time);
+ if (dcon->switched && ktime_to_ns(delta_t)
+ < NSEC_PER_MSEC * 20) {
+ pr_err("missed loading, retrying\n");
+ pdata->set_dconload(1);
+ mdelay(41);
+ pdata->set_dconload(0);
+ dcon->load_time = ktime_get();
+ mdelay(41);
+ }
+ }
+
+ dcon_blank_fb(dcon, true);
+ pr_info("The DCON has control\n");
+ break;
+ }
+ default:
+ BUG();
+ }
+
+ dcon->curr_src = source;
+}
+
+static void dcon_set_source(struct dcon_priv *dcon, int arg)
+{
+ if (dcon->pending_src == arg)
+ return;
+
+ dcon->pending_src = arg;
+
+ if (dcon->curr_src != arg)
+ schedule_work(&dcon->switch_source);
+}
+
+static void dcon_set_source_sync(struct dcon_priv *dcon, int arg)
+{
+ dcon_set_source(dcon, arg);
+ flush_scheduled_work();
+}
+
+static ssize_t dcon_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dcon_priv *dcon = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%4.4X\n", dcon->disp_mode);
+}
+
+static ssize_t dcon_sleep_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dcon_priv *dcon = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", dcon->asleep);
+}
+
+static ssize_t dcon_freeze_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dcon_priv *dcon = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", dcon->curr_src == DCON_SOURCE_DCON ? 1 : 0);
+}
+
+static ssize_t dcon_mono_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dcon_priv *dcon = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", dcon->mono);
+}
+
+static ssize_t dcon_resumeline_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", resumeline);
+}
+
+static ssize_t dcon_mono_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ unsigned long enable_mono;
+ int rc;
+
+ rc = kstrtoul(buf, 10, &enable_mono);
+ if (rc)
+ return rc;
+
+ dcon_set_mono_mode(dev_get_drvdata(dev), enable_mono ? true : false);
+
+ return count;
+}
+
+static ssize_t dcon_freeze_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct dcon_priv *dcon = dev_get_drvdata(dev);
+ unsigned long output;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &output);
+ if (ret)
+ return ret;
+
+ pr_info("dcon_freeze_store: %lu\n", output);
+
+ switch (output) {
+ case 0:
+ dcon_set_source(dcon, DCON_SOURCE_CPU);
+ break;
+ case 1:
+ dcon_set_source_sync(dcon, DCON_SOURCE_DCON);
+ break;
+ case 2: /* normally unused */
+ dcon_set_source(dcon, 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)
+{
+ unsigned short rl;
+ int rc;
+
+ rc = kstrtou16(buf, 10, &rl);
+ if (rc)
+ return rc;
+
+ resumeline = rl;
+ dcon_write(dev_get_drvdata(dev), DCON_REG_SCAN_INT, resumeline);
+
+ return count;
+}
+
+static ssize_t dcon_sleep_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ unsigned long output;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &output);
+ if (ret)
+ return ret;
+
+ dcon_sleep(dev_get_drvdata(dev), output ? true : false);
+ 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(monochrome, 0644, dcon_mono_show, dcon_mono_store),
+ __ATTR(resumeline, 0644, dcon_resumeline_show, dcon_resumeline_store),
+};
+
+static int dcon_bl_update(struct backlight_device *dev)
+{
+ struct dcon_priv *dcon = bl_get_data(dev);
+ u8 level = dev->props.brightness & 0x0F;
+
+ if (dev->props.power != FB_BLANK_UNBLANK)
+ level = 0;
+
+ if (level != dcon->bl_val)
+ dcon_set_backlight(dcon, level);
+
+ /* power down the DCON when the screen is blanked */
+ if (!dcon->ignore_fb_events)
+ dcon_sleep(dcon, !!(dev->props.state & BL_CORE_FBBLANK));
+
+ return 0;
+}
+
+static int dcon_bl_get(struct backlight_device *dev)
+{
+ struct dcon_priv *dcon = bl_get_data(dev);
+
+ return dcon->bl_val;
+}
+
+static const struct backlight_ops dcon_bl_ops = {
+ .update_status = dcon_bl_update,
+ .get_brightness = dcon_bl_get,
+};
+
+static struct backlight_properties dcon_bl_props = {
+ .max_brightness = 15,
+ .type = BACKLIGHT_RAW,
+ .power = FB_BLANK_UNBLANK,
+};
+
+static int dcon_reboot_notify(struct notifier_block *nb,
+ unsigned long foo, void *bar)
+{
+ struct dcon_priv *dcon = container_of(nb, struct dcon_priv, reboot_nb);
+
+ if (!dcon || !dcon->client)
+ return NOTIFY_DONE;
+
+ /* Turn off the DCON. Entirely. */
+ dcon_write(dcon, DCON_REG_MODE, 0x39);
+ dcon_write(dcon, DCON_REG_MODE, 0x32);
+ return NOTIFY_DONE;
+}
+
+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,
+};
+
+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)
+{
+ struct dcon_priv *dcon;
+ int rc, i, j;
+
+ if (!pdata)
+ return -ENXIO;
+
+ dcon = kzalloc(sizeof(*dcon), GFP_KERNEL);
+ if (!dcon)
+ return -ENOMEM;
+
+ dcon->client = client;
+ init_waitqueue_head(&dcon->waitq);
+ INIT_WORK(&dcon->switch_source, dcon_source_switch);
+ dcon->reboot_nb.notifier_call = dcon_reboot_notify;
+ dcon->reboot_nb.priority = -1;
+
+ i2c_set_clientdata(client, dcon);
+
+ if (num_registered_fb < 1) {
+ dev_err(&client->dev, "DCON driver requires a registered fb\n");
+ rc = -EIO;
+ goto einit;
+ }
+ dcon->fbinfo = registered_fb[0];
+
+ rc = dcon_hw_init(dcon, 1);
+ if (rc)
+ goto einit;
+
+ /* Add the DCON device */
+
+ dcon_device = platform_device_alloc("dcon", -1);
+
+ if (!dcon_device) {
+ pr_err("Unable to create the DCON device\n");
+ rc = -ENOMEM;
+ goto eirq;
+ }
+ rc = platform_device_add(dcon_device);
+ platform_set_drvdata(dcon_device, dcon);
+
+ if (rc) {
+ pr_err("Unable to add the DCON device\n");
+ goto edev;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(dcon_device_files); i++) {
+ rc = device_create_file(&dcon_device->dev,
+ &dcon_device_files[i]);
+ if (rc) {
+ dev_err(&dcon_device->dev, "Cannot create sysfs file\n");
+ goto ecreate;
+ }
+ }
+
+ dcon->bl_val = dcon_read(dcon, DCON_REG_BRIGHT) & 0x0F;
+
+ /* Add the backlight device for the DCON */
+ dcon_bl_props.brightness = dcon->bl_val;
+ dcon->bl_dev = backlight_device_register("dcon-bl", &dcon_device->dev,
+ dcon, &dcon_bl_ops, &dcon_bl_props);
+ if (IS_ERR(dcon->bl_dev)) {
+ dev_err(&client->dev, "cannot register backlight dev (%ld)\n",
+ PTR_ERR(dcon->bl_dev));
+ dcon->bl_dev = NULL;
+ }
+
+ register_reboot_notifier(&dcon->reboot_nb);
+ atomic_notifier_chain_register(&panic_notifier_list, &dcon_panic_nb);
+
+ return 0;
+
+ ecreate:
+ for (j = 0; j < i; j++)
+ device_remove_file(&dcon_device->dev, &dcon_device_files[j]);
+ edev:
+ platform_device_unregister(dcon_device);
+ dcon_device = NULL;
+ eirq:
+ free_irq(DCON_IRQ, dcon);
+ einit:
+ kfree(dcon);
+ return rc;
+}
+
+static int dcon_remove(struct i2c_client *client)
+{
+ struct dcon_priv *dcon = i2c_get_clientdata(client);
+
+ unregister_reboot_notifier(&dcon->reboot_nb);
+ atomic_notifier_chain_unregister(&panic_notifier_list, &dcon_panic_nb);
+
+ free_irq(DCON_IRQ, dcon);
+
+ backlight_device_unregister(dcon->bl_dev);
+
+ if (dcon_device)
+ platform_device_unregister(dcon_device);
+ cancel_work_sync(&dcon->switch_source);
+
+ kfree(dcon);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int dcon_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct dcon_priv *dcon = i2c_get_clientdata(client);
+
+ if (!dcon->asleep) {
+ /* Set up the DCON to have the source */
+ dcon_set_source_sync(dcon, DCON_SOURCE_DCON);
+ }
+
+ return 0;
+}
+
+static int dcon_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct dcon_priv *dcon = i2c_get_clientdata(client);
+
+ if (!dcon->asleep) {
+ dcon_bus_stabilize(dcon, 0);
+ dcon_set_source(dcon, DCON_SOURCE_CPU);
+ }
+
+ return 0;
+}
+
+#else
+
+#define dcon_suspend NULL
+#define dcon_resume NULL
+
+#endif /* CONFIG_PM */
+
+irqreturn_t dcon_interrupt(int irq, void *id)
+{
+ struct dcon_priv *dcon = id;
+ u8 status;
+
+ if (pdata->read_status(&status))
+ return IRQ_NONE;
+
+ switch (status & 3) {
+ case 3:
+ pr_debug("DCONLOAD_MISSED interrupt\n");
+ break;
+
+ case 2: /* switch to DCON mode */
+ case 1: /* switch to CPU mode */
+ dcon->switched = true;
+ dcon->irq_time = ktime_get();
+ wake_up(&dcon->waitq);
+ 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->curr_src != dcon->pending_src && !dcon->switched) {
+ dcon->switched = true;
+ dcon->irq_time = ktime_get();
+ wake_up(&dcon->waitq);
+ pr_debug("switching w/ status 0/0\n");
+ } else {
+ pr_debug("scanline interrupt w/CPU\n");
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static const struct dev_pm_ops dcon_pm_ops = {
+ .suspend = dcon_suspend,
+ .resume = dcon_resume,
+};
+
+static const 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",
+ .pm = &dcon_pm_ops,
+ },
+ .class = I2C_CLASS_DDC | I2C_CLASS_HWMON,
+ .id_table = dcon_idtable,
+ .probe = dcon_probe,
+ .remove = dcon_remove,
+ .detect = dcon_detect,
+ .address_list = normal_i2c,
+};
+
+static int __init olpc_dcon_init(void)
+{
+#ifdef CONFIG_FB_OLPC_DCON_1_5
+ /* XO-1.5 */
+ if (olpc_board_at_least(olpc_board(0xd0)))
+ pdata = &dcon_pdata_xo_1_5;
+#endif
+#ifdef CONFIG_FB_OLPC_DCON_1
+ if (!pdata)
+ pdata = &dcon_pdata_xo_1;
+#endif
+
+ return i2c_add_driver(&dcon_driver);
+}
+
+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");
--- /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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cs5535.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <asm/olpc.h>
+
+#include "olpc_dcon.h"
+
+static int dcon_init_xo_1(struct dcon_priv *dcon)
+{
+ unsigned char lob;
+
+ if (gpio_request(OLPC_GPIO_DCON_STAT0, "OLPC-DCON")) {
+ pr_err("failed to request STAT0 GPIO\n");
+ return -EIO;
+ }
+ if (gpio_request(OLPC_GPIO_DCON_STAT1, "OLPC-DCON")) {
+ pr_err("failed to request STAT1 GPIO\n");
+ goto err_gp_stat1;
+ }
+ if (gpio_request(OLPC_GPIO_DCON_IRQ, "OLPC-DCON")) {
+ pr_err("failed to request IRQ GPIO\n");
+ goto err_gp_irq;
+ }
+ if (gpio_request(OLPC_GPIO_DCON_LOAD, "OLPC-DCON")) {
+ pr_err("failed to request LOAD GPIO\n");
+ goto err_gp_load;
+ }
+ if (gpio_request(OLPC_GPIO_DCON_BLANK, "OLPC-DCON")) {
+ pr_err("failed to request BLANK GPIO\n");
+ goto err_gp_blank;
+ }
+
+ /* Turn off the event enable for GPIO7 just to be safe */
+ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE);
+
+ /*
+ * Determine the current state by reading the GPIO bit; earlier
+ * stages of the boot process have established the state.
+ *
+ * Note that we read GPIO_OUTPUT_VAL rather than GPIO_READ_BACK here;
+ * this is because OFW will disable input for the pin and set a value..
+ * READ_BACK will only contain a valid value if input is enabled and
+ * then a value is set. So, future readings of the pin can use
+ * READ_BACK, but the first one cannot. Awesome, huh?
+ */
+ dcon->curr_src = cs5535_gpio_isset(OLPC_GPIO_DCON_LOAD, GPIO_OUTPUT_VAL)
+ ? DCON_SOURCE_CPU
+ : DCON_SOURCE_DCON;
+ dcon->pending_src = dcon->curr_src;
+
+ /* Set the directions for the GPIO pins */
+ gpio_direction_input(OLPC_GPIO_DCON_STAT0);
+ gpio_direction_input(OLPC_GPIO_DCON_STAT1);
+ gpio_direction_input(OLPC_GPIO_DCON_IRQ);
+ gpio_direction_input(OLPC_GPIO_DCON_BLANK);
+ gpio_direction_output(OLPC_GPIO_DCON_LOAD,
+ dcon->curr_src == DCON_SOURCE_CPU);
+
+ /* Set up the interrupt mappings */
+
+ /* Set the IRQ to pair 2 */
+ cs5535_gpio_setup_event(OLPC_GPIO_DCON_IRQ, 2, 0);
+
+ /* Enable group 2 to trigger the DCON interrupt */
+ cs5535_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 interrupt handler */
+ if (request_irq(DCON_IRQ, &dcon_interrupt, 0, "DCON", dcon)) {
+ pr_err("failed to request DCON's irq\n");
+ goto err_req_irq;
+ }
+
+ /* Clear INV_EN for GPIO7 (DCONIRQ) */
+ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_INVERT);
+
+ /* Enable filter for GPIO12 (DCONBLANK) */
+ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_FILTER);
+
+ /* Disable filter for GPIO7 */
+ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_FILTER);
+
+ /* Disable event counter for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
+ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_EVENT_COUNT);
+ cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_EVENT_COUNT);
+
+ /* Add GPIO12 to the Filter Event Pair #7 */
+ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_FE7_SEL);
+
+ /* Turn off negative Edge Enable for GPIO12 */
+ cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_EN);
+
+ /* Enable negative Edge Enable for GPIO7 */
+ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_EN);
+
+ /* Zero the filter amount for Filter Event Pair #7 */
+ cs5535_gpio_set(0, GPIO_FLTR7_AMOUNT);
+
+ /* Clear the negative edge status for GPIO7 and GPIO12 */
+ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_STS);
+
+ /* FIXME: Clear the positive status as well, just to be sure */
+ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_POSITIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_POSITIVE_EDGE_STS);
+
+ /* Enable events for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
+ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE);
+ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_EVENTS_ENABLE);
+
+ return 0;
+
+err_req_irq:
+ gpio_free(OLPC_GPIO_DCON_BLANK);
+err_gp_blank:
+ gpio_free(OLPC_GPIO_DCON_LOAD);
+err_gp_load:
+ gpio_free(OLPC_GPIO_DCON_IRQ);
+err_gp_irq:
+ gpio_free(OLPC_GPIO_DCON_STAT1);
+err_gp_stat1:
+ gpio_free(OLPC_GPIO_DCON_STAT0);
+ return -EIO;
+}
+
+static void dcon_wiggle_xo_1(void)
+{
+ int x;
+
+ /*
+ * According to HiMax, when powering the DCON up we should hold
+ * SMB_DATA high for 8 SMB_CLK cycles. This will force the DCON
+ * state machine to reset to a (sane) initial state. Mitch Bradley
+ * did some testing and discovered that holding for 16 SMB_CLK cycles
+ * worked a lot more reliably, so that's what we do here.
+ *
+ * According to the cs5536 spec, to set GPIO14 to SMB_CLK we must
+ * simultaneously set AUX1 IN/OUT to GPIO14; ditto for SMB_DATA and
+ * GPIO15.
+ */
+ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
+ cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_VAL);
+ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_ENABLE);
+ cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_ENABLE);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX2);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX2);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1);
+
+ for (x = 0; x < 16; x++) {
+ udelay(5);
+ cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
+ udelay(5);
+ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
+ }
+ udelay(5);
+ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1);
+ cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1);
+ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1);
+ cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1);
+}
+
+static void dcon_set_dconload_1(int val)
+{
+ gpio_set_value(OLPC_GPIO_DCON_LOAD, val);
+}
+
+static int dcon_read_status_xo_1(u8 *status)
+{
+ *status = gpio_get_value(OLPC_GPIO_DCON_STAT0);
+ *status |= gpio_get_value(OLPC_GPIO_DCON_STAT1) << 1;
+
+ /* Clear the negative edge status for GPIO7 */
+ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS);
+
+ return 0;
+}
+
+struct dcon_platform_data dcon_pdata_xo_1 = {
+ .init = dcon_init_xo_1,
+ .bus_stabilize_wiggle = dcon_wiggle_xo_1,
+ .set_dconload = dcon_set_dconload_1,
+ .read_status = dcon_read_status_xo_1,
+};
projects / openwrt / staging / blogic.git / commitdiff