diff options
Diffstat (limited to 'arch/x86/platform/olpc/olpc-xo15-sci.c')
| -rw-r--r-- | arch/x86/platform/olpc/olpc-xo15-sci.c | 238 |
1 files changed, 238 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 00000000..23e5b9d7 --- /dev/null +++ b/arch/x86/platform/olpc/olpc-xo15-sci.c @@ -0,0 +1,238 @@ +/* + * 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 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 oportunistically + * 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) +{ + struct acpi_object_list arg_list; + union acpi_object arg; + acpi_status status; + + arg_list.count = 1; + arg_list.pointer = &arg; + arg.type = ACPI_TYPE_INTEGER; + arg.integer.value = wake_on_close; + + status = acpi_evaluate_object(NULL, "\\_SB.PCI0.LID.LIDW", &arg_list, NULL); + if (ACPI_FAILURE(status)) { + pr_warning(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); + 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; + 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, 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); + sysfs_remove_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); + 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); |