by Daniel Drake

[permalink] [raw]

Subject: [PATCH v3 11/11] x86, olpc: Add XO-1.5 SCI driver

Add a driver for the ACPI-based EC event interface found on the
OLPC XO-1.5 laptop. This enables notification of battery/AC power events,
and enables various devices to be used as wakeup sources through regular
ACPI mechanisms.

This driver can't be built as a module, because some drivers need to know
at boot-time if SCI-based functionality is available via
olpc_ec_wakeup_available().

Signed-off-by: Daniel Drake <[email protected]>
Acked-by: Andres Salomon <[email protected]>
---
arch/x86/Kconfig | 9 ++
arch/x86/platform/olpc/Makefile | 1 +
arch/x86/platform/olpc/olpc-xo15-sci.c | 168 ++++++++++++++++++++++++++++++++
arch/x86/platform/olpc/olpc.c | 9 ++
4 files changed, 187 insertions(+), 0 deletions(-)
create mode 100644 arch/x86/platform/olpc/olpc-xo15-sci.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index de81496..1ed7d32 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2103,6 +2103,15 @@ config OLPC_XO1_SCI
- AC adapter status updates
- Battery status updates

+config OLPC_XO15_SCI
+ bool "OLPC XO-1.5 SCI extras"
+ depends on OLPC && ACPI && POWER_SUPPLY
+ ---help---
+ Add support for SCI-based features of the OLPC XO-1.5 laptop:
+ - EC-driven system wakeups
+ - AC adapter status updates
+ - Battery status updates
+
endif # X86_32

config AMD_NB
diff --git a/arch/x86/platform/olpc/Makefile b/arch/x86/platform/olpc/Makefile
index 8922b9b..fd332c5 100644
--- a/arch/x86/platform/olpc/Makefile
+++ b/arch/x86/platform/olpc/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_OLPC) += olpc.o olpc_ofw.o olpc_dt.o
obj-$(CONFIG_OLPC_XO1_PM) += olpc-xo1-pm.o xo1-wakeup.o
obj-$(CONFIG_OLPC_XO1_RTC) += olpc-xo1-rtc.o
obj-$(CONFIG_OLPC_XO1_SCI) += olpc-xo1-sci.o
+obj-$(CONFIG_OLPC_XO15_SCI) += olpc-xo15-sci.o
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 0000000..a5990eb
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc-xo15-sci.c
@@ -0,0 +1,168 @@
+/*
+ * Support for OLPC XO-1.5 System Control Interrupts (SCI)
+ *
+ * Copyright (C) 2009-2010 One Laptop per Child
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/power_supply.h>
+
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.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 void battery_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc-battery");
+
+ if (psy) {
+ power_supply_changed(psy);
+ put_device(psy->dev);
+ }
+}
+
+static void ac_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc-ac");
+
+ if (psy) {
+ power_supply_changed(psy);
+ put_device(psy->dev);
+ }
+}
+
+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;
+
+ 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);
+
+ /* 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_set_wakeup_enable(&device->dev, true);
+
+ return 0;
+}
+
+static int xo15_sci_remove(struct acpi_device *device, int type)
+{
+ acpi_disable_gpe(NULL, xo15_sci_gpe);
+ acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler);
+ cancel_work_sync(&sci_work);
+ return 0;
+}
+
+static int xo15_sci_resume(struct acpi_device *device)
+{
+ /* 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;
+}
+
+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,
+ .resume = xo15_sci_resume,
+ },
+};
+
+static int __init xo15_sci_init(void)
+{
+ return acpi_bus_register_driver(&xo15_sci_drv);
+}
+device_initcall(xo15_sci_init);
diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index 72fd041..8b9940e 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -222,6 +222,15 @@ bool olpc_ec_wakeup_available(void)
return true;
#endif

+ /*
+ * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
+ * compiled in
+ */
+#ifdef CONFIG_OLPC_XO15_SCI
+ if (olpc_platform_info.boardrev >= olpc_board_pre(0xd0)) /* XO-1.5 */
+ return true;
+#endif
+
return false;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
--
1.7.5.4