[Intel-gfx] [RFC] i915/acpi: add lid status notification and detection
Jesse Barnes
jbarnes at virtuousgeek.org
Wed May 13 20:57:34 CEST 2009
In the i915 driver we want to know if the lid is open or closed and
when its status changes, since we want to use the closed state to
indicate that the LFP is unavailable (disconnected in KMS terms) and
open to indicate that it's usable.
To that end, this patch adds some code to the ACPI button driver to
send us lid notifications as they occur and provide us with current lid
status when called.
It's a bit ugly, and I don't handle the inter-module dependencies very
well at this point, but you should get the idea.
There's also a policy question here. On some machines, a lid close
will cause the ACPI firmware to program the GPU, disabling the pipe
associated with the panel. Should we detect this and turn it back on
at open time? That could be dangerous if userspace has received the
LVDS hotplug event and changed the config out from under us...
Comments?
--
Jesse Barnes, Intel Open Source Technology Center
diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index 9195deb..ebb593e 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -113,6 +113,9 @@ static const struct file_operations acpi_button_state_fops = {
.release = single_release,
};
+static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
+static struct acpi_device *lid_device;
+
/* --------------------------------------------------------------------------
FS Interface (/proc)
-------------------------------------------------------------------------- */
@@ -229,11 +232,38 @@ static int acpi_button_remove_fs(struct acpi_device *device)
/* --------------------------------------------------------------------------
Driver Interface
-------------------------------------------------------------------------- */
+int acpi_lid_notifier_register(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
+}
+EXPORT_SYMBOL(acpi_lid_notifier_register);
+
+int acpi_lid_notifier_unregister(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
+}
+EXPORT_SYMBOL(acpi_lid_notifier_unregister);
+
+int acpi_lid_open(void)
+{
+ acpi_status status;
+ unsigned long long state;
+
+ status = acpi_evaluate_integer(lid_device->handle, "_LID", NULL,
+ &state);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ return !!state;
+}
+EXPORT_SYMBOL(acpi_lid_open);
+
static int acpi_lid_send_state(struct acpi_device *device)
{
struct acpi_button *button = acpi_driver_data(device);
unsigned long long state;
acpi_status status;
+ int ret;
status = acpi_evaluate_integer(device->handle, "_LID", NULL, &state);
if (ACPI_FAILURE(status))
@@ -242,7 +272,12 @@ static int acpi_lid_send_state(struct acpi_device *device)
/* input layer checks if event is redundant */
input_report_switch(button->input, SW_LID, !state);
input_sync(button->input);
- return 0;
+
+ ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
+ if (ret == NOTIFY_DONE)
+ ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
+ device);
+ return ret;
}
static void acpi_button_notify(struct acpi_device *device, u32 event)
@@ -364,8 +399,14 @@ static int acpi_button_add(struct acpi_device *device)
error = input_register_device(input);
if (error)
goto err_remove_fs;
- if (button->type == ACPI_BUTTON_TYPE_LID)
+ if (button->type == ACPI_BUTTON_TYPE_LID) {
acpi_lid_send_state(device);
+ /*
+ * This assumes there's only one lid device, or if there are
+ * more we only care about the last one...
+ */
+ lid_device = device;
+ }
if (device->wakeup.flags.valid) {
/* Button's GPE is run-wake GPE */
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 2506592..fb12fb9 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -190,6 +190,8 @@ typedef struct drm_i915_private {
unsigned int lvds_use_ssc:1;
int lvds_ssc_freq;
+ struct notifier_block lid_notifier;
+
struct drm_i915_fence_reg fence_regs[16]; /* assume 965 */
int fence_reg_start; /* 4 if userland hasn't ioctl'd us yet */
int num_fence_regs; /* 8 on pre-965, 16 otherwise */
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index bdcda36..08c1260 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -24,6 +24,8 @@
* Eric Anholt <eric at anholt.net>
*/
+#include <linux/module.h>
+#include <linux/input.h>
#include <linux/i2c.h>
#include "drmP.h"
#include "intel_drv.h"
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 6619f26..8f05b09 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -27,6 +27,7 @@
* Jesse Barnes <jesse.barnes at intel.com>
*/
+#include <acpi/button.h>
#include <linux/dmi.h>
#include <linux/i2c.h>
#include "drmP.h"
@@ -277,12 +278,18 @@ static void intel_lvds_mode_set(struct drm_encoder *encoder,
/**
* Detect the LVDS connection.
*
- * This always returns CONNECTOR_STATUS_CONNECTED. This connector should only have
- * been set up if the LVDS was actually connected anyway.
+ * Since LVDS doesn't have hotlug, we use the lid as a proxy. Open means
+ * connected and closed means disconnected. We also send hotplug events as
+ * needed, using lid status notification from the input layer.
*/
static enum drm_connector_status intel_lvds_detect(struct drm_connector *connector)
{
- return connector_status_connected;
+ enum drm_connector_status status = connector_status_connected;
+
+ if (!acpi_lid_open())
+ status = connector_status_disconnected;
+
+ return status;
}
/**
@@ -321,6 +328,17 @@ static int intel_lvds_get_modes(struct drm_connector *connector)
return 0;
}
+static int intel_lid_notify(struct notifier_block *nb, unsigned long val,
+ void *unused)
+{
+ struct drm_i915_private *dev_priv =
+ container_of(nb, struct drm_i915_private, lid_notifier);
+
+ drm_sysfs_hotplug_event(dev_priv->dev);
+
+ return NOTIFY_OK;
+}
+
/**
* intel_lvds_destroy - unregister and free LVDS structures
* @connector: connector to free
@@ -330,10 +348,14 @@ static int intel_lvds_get_modes(struct drm_connector *connector)
*/
static void intel_lvds_destroy(struct drm_connector *connector)
{
+ struct drm_device *dev = connector->dev;
struct intel_output *intel_output = to_intel_output(connector);
+ struct drm_i915_private *dev_priv = dev->dev_private;
if (intel_output->ddc_bus)
intel_i2c_destroy(intel_output->ddc_bus);
+ if (dev_priv->lid_notifier.notifier_call)
+ acpi_lid_notifier_unregister(&dev_priv->lid_notifier);
drm_sysfs_connector_remove(connector);
drm_connector_cleanup(connector);
kfree(connector);
@@ -508,6 +530,11 @@ void intel_lvds_init(struct drm_device *dev)
goto failed;
out:
+ dev_priv->lid_notifier.notifier_call = intel_lid_notify;
+ if (acpi_lid_notifier_register(&dev_priv->lid_notifier)) {
+ DRM_DEBUG("lid notifier registration failed\n");
+ dev_priv->lid_notifier.notifier_call = NULL;
+ }
drm_sysfs_connector_add(connector);
return;
diff --git a/include/acpi/button.h b/include/acpi/button.h
new file mode 100644
index 0000000..bb643a7
--- /dev/null
+++ b/include/acpi/button.h
@@ -0,0 +1,10 @@
+#ifndef ACPI_BUTTON_H
+#define ACPI_BUTTON_H
+
+#include <linux/notifier.h>
+
+extern int acpi_lid_notifier_register(struct notifier_block *nb);
+extern int acpi_lid_notifier_unregister(struct notifier_block *nb);
+extern int acpi_lid_open(void);
+
+#endif /* ACPI_BUTTON_H */
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