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-rw-r--r--arch/x86/platform/olpc/olpc-xo15-sci.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/olpc-xo15-sci.c b/arch/x86/platform/olpc/olpc-xo15-sci.c
new file mode 100644
index 000000000..994a229cb
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc-xo15-sci.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Support for OLPC XO-1.5 System Control Interrupts (SCI)
+ *
+ * Copyright (C) 2009-2010 One Laptop per Child
+ */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/power_supply.h>
+#include <linux/olpc-ec.h>
+
+#include <linux/acpi.h>
+#include <asm/olpc.h>
+
+#define DRV_NAME "olpc-xo15-sci"
+#define PFX DRV_NAME ": "
+#define XO15_SCI_CLASS DRV_NAME
+#define XO15_SCI_DEVICE_NAME "OLPC XO-1.5 SCI"
+
+static unsigned long xo15_sci_gpe;
+static bool lid_wake_on_close;
+
+/*
+ * The normal ACPI LID wakeup behavior is wake-on-open, but not
+ * wake-on-close. This is implemented as standard by the XO-1.5 DSDT.
+ *
+ * We provide here a sysfs attribute that will additionally enable
+ * wake-on-close behavior. This is useful (e.g.) when we opportunistically
+ * suspend with the display running; if the lid is then closed, we want to
+ * wake up to turn the display off.
+ *
+ * This is controlled through a custom method in the XO-1.5 DSDT.
+ */
+static int set_lid_wake_behavior(bool wake_on_close)
+{
+ acpi_status status;
+
+ status = acpi_execute_simple_method(NULL, "\\_SB.PCI0.LID.LIDW", wake_on_close);
+ if (ACPI_FAILURE(status)) {
+ pr_warn(PFX "failed to set lid behavior\n");
+ return 1;
+ }
+
+ lid_wake_on_close = wake_on_close;
+
+ return 0;
+}
+
+static ssize_t
+lid_wake_on_close_show(struct kobject *s, struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u\n", lid_wake_on_close);
+}
+
+static ssize_t lid_wake_on_close_store(struct kobject *s,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned int val;
+
+ if (sscanf(buf, "%u", &val) != 1)
+ return -EINVAL;
+
+ set_lid_wake_behavior(!!val);
+
+ return n;
+}
+
+static struct kobj_attribute lid_wake_on_close_attr =
+ __ATTR(lid_wake_on_close, 0644,
+ lid_wake_on_close_show,
+ lid_wake_on_close_store);
+
+static void battery_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc_battery");
+
+ if (psy) {
+ power_supply_changed(psy);
+ power_supply_put(psy);
+ }
+}
+
+static void ac_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc_ac");
+
+ if (psy) {
+ power_supply_changed(psy);
+ power_supply_put(psy);
+ }
+}
+
+static void process_sci_queue(void)
+{
+ u16 data;
+ int r;
+
+ do {
+ r = olpc_ec_sci_query(&data);
+ if (r || !data)
+ break;
+
+ pr_debug(PFX "SCI 0x%x received\n", data);
+
+ switch (data) {
+ case EC_SCI_SRC_BATERR:
+ case EC_SCI_SRC_BATSOC:
+ case EC_SCI_SRC_BATTERY:
+ case EC_SCI_SRC_BATCRIT:
+ battery_status_changed();
+ break;
+ case EC_SCI_SRC_ACPWR:
+ ac_status_changed();
+ break;
+ }
+ } while (data);
+
+ if (r)
+ pr_err(PFX "Failed to clear SCI queue");
+}
+
+static void process_sci_queue_work(struct work_struct *work)
+{
+ process_sci_queue();
+}
+
+static DECLARE_WORK(sci_work, process_sci_queue_work);
+
+static u32 xo15_sci_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context)
+{
+ schedule_work(&sci_work);
+ return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
+}
+
+static int xo15_sci_add(struct acpi_device *device)
+{
+ unsigned long long tmp;
+ acpi_status status;
+ int r;
+
+ if (!device)
+ return -EINVAL;
+
+ strcpy(acpi_device_name(device), XO15_SCI_DEVICE_NAME);
+ strcpy(acpi_device_class(device), XO15_SCI_CLASS);
+
+ /* Get GPE bit assignment (EC events). */
+ status = acpi_evaluate_integer(device->handle, "_GPE", NULL, &tmp);
+ if (ACPI_FAILURE(status))
+ return -EINVAL;
+
+ xo15_sci_gpe = tmp;
+ status = acpi_install_gpe_handler(NULL, xo15_sci_gpe,
+ ACPI_GPE_EDGE_TRIGGERED,
+ xo15_sci_gpe_handler, device);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ dev_info(&device->dev, "Initialized, GPE = 0x%lx\n", xo15_sci_gpe);
+
+ r = sysfs_create_file(&device->dev.kobj, &lid_wake_on_close_attr.attr);
+ if (r)
+ goto err_sysfs;
+
+ /* Flush queue, and enable all SCI events */
+ process_sci_queue();
+ olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+ acpi_enable_gpe(NULL, xo15_sci_gpe);
+
+ /* Enable wake-on-EC */
+ if (device->wakeup.flags.valid)
+ device_init_wakeup(&device->dev, true);
+
+ return 0;
+
+err_sysfs:
+ acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler);
+ cancel_work_sync(&sci_work);
+ return r;
+}
+
+static int xo15_sci_remove(struct acpi_device *device)
+{
+ acpi_disable_gpe(NULL, xo15_sci_gpe);
+ acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler);
+ cancel_work_sync(&sci_work);
+ sysfs_remove_file(&device->dev.kobj, &lid_wake_on_close_attr.attr);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int xo15_sci_resume(struct device *dev)
+{
+ /* Enable all EC events */
+ olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+ /* Power/battery status might have changed */
+ battery_status_changed();
+ ac_status_changed();
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(xo15_sci_pm, NULL, xo15_sci_resume);
+
+static const struct acpi_device_id xo15_sci_device_ids[] = {
+ {"XO15EC", 0},
+ {"", 0},
+};
+
+static struct acpi_driver xo15_sci_drv = {
+ .name = DRV_NAME,
+ .class = XO15_SCI_CLASS,
+ .ids = xo15_sci_device_ids,
+ .ops = {
+ .add = xo15_sci_add,
+ .remove = xo15_sci_remove,
+ },
+ .drv.pm = &xo15_sci_pm,
+};
+
+static int __init xo15_sci_init(void)
+{
+ return acpi_bus_register_driver(&xo15_sci_drv);
+}
+device_initcall(xo15_sci_init);