1 /* 2 * Support for OLPC XO-1.5 System Control Interrupts (SCI) 3 * 4 * Copyright (C) 2009-2010 One Laptop per Child 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 */ 11 12 #include <linux/device.h> 13 #include <linux/slab.h> 14 #include <linux/workqueue.h> 15 #include <linux/power_supply.h> 16 #include <linux/olpc-ec.h> 17 18 #include <linux/acpi.h> 19 #include <asm/olpc.h> 20 21 #define DRV_NAME "olpc-xo15-sci" 22 #define PFX DRV_NAME ": " 23 #define XO15_SCI_CLASS DRV_NAME 24 #define XO15_SCI_DEVICE_NAME "OLPC XO-1.5 SCI" 25 26 static unsigned long xo15_sci_gpe; 27 static bool lid_wake_on_close; 28 29 /* 30 * The normal ACPI LID wakeup behavior is wake-on-open, but not 31 * wake-on-close. This is implemented as standard by the XO-1.5 DSDT. 32 * 33 * We provide here a sysfs attribute that will additionally enable 34 * wake-on-close behavior. This is useful (e.g.) when we oportunistically 35 * suspend with the display running; if the lid is then closed, we want to 36 * wake up to turn the display off. 37 * 38 * This is controlled through a custom method in the XO-1.5 DSDT. 39 */ 40 static int set_lid_wake_behavior(bool wake_on_close) 41 { 42 acpi_status status; 43 44 status = acpi_execute_simple_method(NULL, "\\_SB.PCI0.LID.LIDW", wake_on_close); 45 if (ACPI_FAILURE(status)) { 46 pr_warning(PFX "failed to set lid behavior\n"); 47 return 1; 48 } 49 50 lid_wake_on_close = wake_on_close; 51 52 return 0; 53 } 54 55 static ssize_t 56 lid_wake_on_close_show(struct kobject *s, struct kobj_attribute *attr, char *buf) 57 { 58 return sprintf(buf, "%u\n", lid_wake_on_close); 59 } 60 61 static ssize_t lid_wake_on_close_store(struct kobject *s, 62 struct kobj_attribute *attr, 63 const char *buf, size_t n) 64 { 65 unsigned int val; 66 67 if (sscanf(buf, "%u", &val) != 1) 68 return -EINVAL; 69 70 set_lid_wake_behavior(!!val); 71 72 return n; 73 } 74 75 static struct kobj_attribute lid_wake_on_close_attr = 76 __ATTR(lid_wake_on_close, 0644, 77 lid_wake_on_close_show, 78 lid_wake_on_close_store); 79 80 static void battery_status_changed(void) 81 { 82 struct power_supply *psy = power_supply_get_by_name("olpc-battery"); 83 84 if (psy) { 85 power_supply_changed(psy); 86 power_supply_put(psy); 87 } 88 } 89 90 static void ac_status_changed(void) 91 { 92 struct power_supply *psy = power_supply_get_by_name("olpc-ac"); 93 94 if (psy) { 95 power_supply_changed(psy); 96 power_supply_put(psy); 97 } 98 } 99 100 static void process_sci_queue(void) 101 { 102 u16 data; 103 int r; 104 105 do { 106 r = olpc_ec_sci_query(&data); 107 if (r || !data) 108 break; 109 110 pr_debug(PFX "SCI 0x%x received\n", data); 111 112 switch (data) { 113 case EC_SCI_SRC_BATERR: 114 case EC_SCI_SRC_BATSOC: 115 case EC_SCI_SRC_BATTERY: 116 case EC_SCI_SRC_BATCRIT: 117 battery_status_changed(); 118 break; 119 case EC_SCI_SRC_ACPWR: 120 ac_status_changed(); 121 break; 122 } 123 } while (data); 124 125 if (r) 126 pr_err(PFX "Failed to clear SCI queue"); 127 } 128 129 static void process_sci_queue_work(struct work_struct *work) 130 { 131 process_sci_queue(); 132 } 133 134 static DECLARE_WORK(sci_work, process_sci_queue_work); 135 136 static u32 xo15_sci_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context) 137 { 138 schedule_work(&sci_work); 139 return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; 140 } 141 142 static int xo15_sci_add(struct acpi_device *device) 143 { 144 unsigned long long tmp; 145 acpi_status status; 146 int r; 147 148 if (!device) 149 return -EINVAL; 150 151 strcpy(acpi_device_name(device), XO15_SCI_DEVICE_NAME); 152 strcpy(acpi_device_class(device), XO15_SCI_CLASS); 153 154 /* Get GPE bit assignment (EC events). */ 155 status = acpi_evaluate_integer(device->handle, "_GPE", NULL, &tmp); 156 if (ACPI_FAILURE(status)) 157 return -EINVAL; 158 159 xo15_sci_gpe = tmp; 160 status = acpi_install_gpe_handler(NULL, xo15_sci_gpe, 161 ACPI_GPE_EDGE_TRIGGERED, 162 xo15_sci_gpe_handler, device); 163 if (ACPI_FAILURE(status)) 164 return -ENODEV; 165 166 dev_info(&device->dev, "Initialized, GPE = 0x%lx\n", xo15_sci_gpe); 167 168 r = sysfs_create_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 169 if (r) 170 goto err_sysfs; 171 172 /* Flush queue, and enable all SCI events */ 173 process_sci_queue(); 174 olpc_ec_mask_write(EC_SCI_SRC_ALL); 175 176 acpi_enable_gpe(NULL, xo15_sci_gpe); 177 178 /* Enable wake-on-EC */ 179 if (device->wakeup.flags.valid) 180 device_init_wakeup(&device->dev, true); 181 182 return 0; 183 184 err_sysfs: 185 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 186 cancel_work_sync(&sci_work); 187 return r; 188 } 189 190 static int xo15_sci_remove(struct acpi_device *device) 191 { 192 acpi_disable_gpe(NULL, xo15_sci_gpe); 193 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 194 cancel_work_sync(&sci_work); 195 sysfs_remove_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 196 return 0; 197 } 198 199 static int xo15_sci_resume(struct device *dev) 200 { 201 /* Enable all EC events */ 202 olpc_ec_mask_write(EC_SCI_SRC_ALL); 203 204 /* Power/battery status might have changed */ 205 battery_status_changed(); 206 ac_status_changed(); 207 208 return 0; 209 } 210 211 static SIMPLE_DEV_PM_OPS(xo15_sci_pm, NULL, xo15_sci_resume); 212 213 static const struct acpi_device_id xo15_sci_device_ids[] = { 214 {"XO15EC", 0}, 215 {"", 0}, 216 }; 217 218 static struct acpi_driver xo15_sci_drv = { 219 .name = DRV_NAME, 220 .class = XO15_SCI_CLASS, 221 .ids = xo15_sci_device_ids, 222 .ops = { 223 .add = xo15_sci_add, 224 .remove = xo15_sci_remove, 225 }, 226 .drv.pm = &xo15_sci_pm, 227 }; 228 229 static int __init xo15_sci_init(void) 230 { 231 return acpi_bus_register_driver(&xo15_sci_drv); 232 } 233 device_initcall(xo15_sci_init); 234