/*
 * Copyright (C) 2017 Mario Limonciello <mario.limonciello@dell.com>
 * Copyright (C) 2017 Peichen Huang <peichenhuang@tw.synaptics.com>
 * Copyright (C) 2017 Richard Hughes <richard@hughsie.com>
 *
 * SPDX-License-Identifier: LGPL-2.1+
 */

#include "config.h"

#include "fu-plugin-vfuncs.h"

#include "fu-synaptics-mst-common.h"
#include "fu-synaptics-mst-device.h"
#include "fu-synaptics-mst-firmware.h"

#define FU_SYNAPTICS_MST_DRM_REPLUG_DELAY	5 /* s */

struct FuPluginData {
	GPtrArray		*devices;
	guint			 drm_changed_id;
};

/* see https://github.com/fwupd/fwupd/issues/1121 for more details */
static gboolean
fu_synaptics_mst_check_amdgpu_safe (GError **error)
{
	gsize bufsz = 0;
	g_autofree gchar *buf = NULL;
	g_auto(GStrv) lines = NULL;

	/* no module support in the kernel, we can't test for amdgpu module */
	if (!g_file_test ("/proc/modules", G_FILE_TEST_EXISTS))
		return TRUE;

	if (!g_file_get_contents ("/proc/modules", &buf, &bufsz, error))
		return FALSE;

	lines = g_strsplit (buf, "\n", -1);
	for (guint i = 0; lines[i] != NULL; i++) {
		if (g_str_has_prefix (lines[i], "amdgpu ")) {
			g_set_error_literal (error,
					     FWUPD_ERROR,
					     FWUPD_ERROR_NOT_SUPPORTED,
					     "amdgpu has known issues with synaptics_mst");
			return FALSE;
		}
	}

	return TRUE;
}

static void
fu_plugin_synaptics_mst_device_rescan (FuPlugin *plugin, FuDevice *device)
{
	g_autoptr(FuDeviceLocker) locker = NULL;
	g_autoptr(GError) error_local = NULL;

	/* open fd */
	locker = fu_device_locker_new (device, &error_local);
	if (locker == NULL) {
		g_debug ("failed to open device %s: %s",
			 fu_device_get_logical_id (device),
			 error_local->message);
		return;
	}
	if (!fu_device_rescan (device, &error_local)) {
		g_debug ("no device found on %s: %s",
			 fu_device_get_logical_id (device),
			 error_local->message);
		if (fu_device_has_flag (device, FWUPD_DEVICE_FLAG_REGISTERED))
			fu_plugin_device_remove (plugin, device);
	} else {
		fu_plugin_device_add (plugin, device);
	}
}

/* reprobe all existing devices added by this plugin */
static void
fu_plugin_synaptics_mst_rescan (FuPlugin *plugin)
{
	FuPluginData *priv = fu_plugin_get_data (plugin);
	for (guint i = 0; i < priv->devices->len; i++) {
		FuDevice *device = FU_DEVICE (g_ptr_array_index (priv->devices, i));
		fu_plugin_synaptics_mst_device_rescan (plugin, device);
	}
}

static gboolean
fu_plugin_synaptics_mst_rescan_cb (gpointer user_data)
{
	FuPlugin *plugin = FU_PLUGIN (user_data);
	FuPluginData *priv = fu_plugin_get_data (plugin);
	fu_plugin_synaptics_mst_rescan (plugin);
	priv->drm_changed_id = 0;
	return FALSE;
}

gboolean
fu_plugin_backend_device_changed (FuPlugin *plugin, FuDevice *device, GError **error)
{
	FuPluginData *priv = fu_plugin_get_data (plugin);

	/* interesting device? */
	if (!FU_IS_UDEV_DEVICE (device))
		return TRUE;
	if (g_strcmp0 (fu_udev_device_get_subsystem (FU_UDEV_DEVICE (device)), "drm") != 0)
		return TRUE;

	/* recoldplug all drm_dp_aux_dev devices after a *long* delay */
	if (priv->drm_changed_id != 0)
		g_source_remove (priv->drm_changed_id);
	priv->drm_changed_id = g_timeout_add_seconds (FU_SYNAPTICS_MST_DRM_REPLUG_DELAY,
						      fu_plugin_synaptics_mst_rescan_cb,
						      plugin);
	return TRUE;
}

gboolean
fu_plugin_backend_device_added (FuPlugin *plugin, FuDevice *device, GError **error)
{
	FuPluginData *priv = fu_plugin_get_data (plugin);
	g_autoptr(FuDeviceLocker) locker = NULL;
	g_autoptr(FuSynapticsMstDevice) dev = NULL;

	/* interesting device? */
	if (!FU_IS_UDEV_DEVICE (device))
		return TRUE;

	dev = fu_synaptics_mst_device_new (FU_UDEV_DEVICE (device));
	locker = fu_device_locker_new (dev, error);
	if (locker == NULL)
		return FALSE;

	/* for DeviceKind=system devices */
	fu_synaptics_mst_device_set_system_type (FU_SYNAPTICS_MST_DEVICE (dev),
						fu_plugin_get_dmi_value (plugin, FU_HWIDS_KEY_PRODUCT_SKU));

	/* this might fail if there is nothing connected */
	fu_plugin_synaptics_mst_device_rescan (plugin, FU_DEVICE (dev));
	g_ptr_array_add (priv->devices, g_steal_pointer (&dev));
	return TRUE;
}

gboolean
fu_plugin_startup (FuPlugin *plugin, GError **error)
{
	return fu_synaptics_mst_check_amdgpu_safe (error);
}

gboolean
fu_plugin_update (FuPlugin *plugin,
		  FuDevice *device,
		  GBytes *blob_fw,
		  FwupdInstallFlags flags,
		  GError **error)
{
	g_autoptr(FuDeviceLocker) locker = fu_device_locker_new (device, error);
	if (locker == NULL)
		return FALSE;
	if (!fu_device_write_firmware (device, blob_fw, flags, error))
		return FALSE;
	if (!fu_device_has_flag (device, FWUPD_DEVICE_FLAG_SKIPS_RESTART))
		fu_plugin_device_remove (plugin, device);
	return TRUE;
}

void
fu_plugin_init (FuPlugin *plugin)
{
	FuPluginData *priv = fu_plugin_alloc_data (plugin, sizeof (FuPluginData));

	/* devices added by this plugin */
	priv->devices = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);

	fu_plugin_set_build_hash (plugin, FU_BUILD_HASH);
	fu_plugin_add_udev_subsystem (plugin, "drm");	/* used for uevent only */
	fu_plugin_add_udev_subsystem (plugin, "drm_dp_aux_dev");
	fu_plugin_add_firmware_gtype (plugin, NULL, FU_TYPE_SYNAPTICS_MST_FIRMWARE);
}

void
fu_plugin_destroy (FuPlugin *plugin)
{
	FuPluginData *priv = fu_plugin_get_data (plugin);
	if (priv->drm_changed_id != 0)
		g_source_remove (priv->drm_changed_id);
	g_ptr_array_unref (priv->devices);
}