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 <acpi/acpi_bus.h> 19 #include <acpi/acpi_drivers.h> 20 #include <asm/olpc.h> 21 22 #define DRV_NAME "olpc-xo15-sci" 23 #define PFX DRV_NAME ": " 24 #define XO15_SCI_CLASS DRV_NAME 25 #define XO15_SCI_DEVICE_NAME "OLPC XO-1.5 SCI" 26 27 static unsigned long xo15_sci_gpe; 28 static bool lid_wake_on_close; 29 30 /* 31 * The normal ACPI LID wakeup behavior is wake-on-open, but not 32 * wake-on-close. This is implemented as standard by the XO-1.5 DSDT. 33 * 34 * We provide here a sysfs attribute that will additionally enable 35 * wake-on-close behavior. This is useful (e.g.) when we oportunistically 36 * suspend with the display running; if the lid is then closed, we want to 37 * wake up to turn the display off. 38 * 39 * This is controlled through a custom method in the XO-1.5 DSDT. 40 */ 41 static int set_lid_wake_behavior(bool wake_on_close) 42 { 43 struct acpi_object_list arg_list; 44 union acpi_object arg; 45 acpi_status status; 46 47 arg_list.count = 1; 48 arg_list.pointer = &arg; 49 arg.type = ACPI_TYPE_INTEGER; 50 arg.integer.value = wake_on_close; 51 52 status = acpi_evaluate_object(NULL, "\\_SB.PCI0.LID.LIDW", &arg_list, NULL); 53 if (ACPI_FAILURE(status)) { 54 pr_warning(PFX "failed to set lid behavior\n"); 55 return 1; 56 } 57 58 lid_wake_on_close = wake_on_close; 59 60 return 0; 61 } 62 63 static ssize_t 64 lid_wake_on_close_show(struct kobject *s, struct kobj_attribute *attr, char *buf) 65 { 66 return sprintf(buf, "%u\n", lid_wake_on_close); 67 } 68 69 static ssize_t lid_wake_on_close_store(struct kobject *s, 70 struct kobj_attribute *attr, 71 const char *buf, size_t n) 72 { 73 unsigned int val; 74 75 if (sscanf(buf, "%u", &val) != 1) 76 return -EINVAL; 77 78 set_lid_wake_behavior(!!val); 79 80 return n; 81 } 82 83 static struct kobj_attribute lid_wake_on_close_attr = 84 __ATTR(lid_wake_on_close, 0644, 85 lid_wake_on_close_show, 86 lid_wake_on_close_store); 87 88 static void battery_status_changed(void) 89 { 90 struct power_supply *psy = power_supply_get_by_name("olpc-battery"); 91 92 if (psy) { 93 power_supply_changed(psy); 94 put_device(psy->dev); 95 } 96 } 97 98 static void ac_status_changed(void) 99 { 100 struct power_supply *psy = power_supply_get_by_name("olpc-ac"); 101 102 if (psy) { 103 power_supply_changed(psy); 104 put_device(psy->dev); 105 } 106 } 107 108 static void process_sci_queue(void) 109 { 110 u16 data; 111 int r; 112 113 do { 114 r = olpc_ec_sci_query(&data); 115 if (r || !data) 116 break; 117 118 pr_debug(PFX "SCI 0x%x received\n", data); 119 120 switch (data) { 121 case EC_SCI_SRC_BATERR: 122 case EC_SCI_SRC_BATSOC: 123 case EC_SCI_SRC_BATTERY: 124 case EC_SCI_SRC_BATCRIT: 125 battery_status_changed(); 126 break; 127 case EC_SCI_SRC_ACPWR: 128 ac_status_changed(); 129 break; 130 } 131 } while (data); 132 133 if (r) 134 pr_err(PFX "Failed to clear SCI queue"); 135 } 136 137 static void process_sci_queue_work(struct work_struct *work) 138 { 139 process_sci_queue(); 140 } 141 142 static DECLARE_WORK(sci_work, process_sci_queue_work); 143 144 static u32 xo15_sci_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context) 145 { 146 schedule_work(&sci_work); 147 return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; 148 } 149 150 static int xo15_sci_add(struct acpi_device *device) 151 { 152 unsigned long long tmp; 153 acpi_status status; 154 int r; 155 156 if (!device) 157 return -EINVAL; 158 159 strcpy(acpi_device_name(device), XO15_SCI_DEVICE_NAME); 160 strcpy(acpi_device_class(device), XO15_SCI_CLASS); 161 162 /* Get GPE bit assignment (EC events). */ 163 status = acpi_evaluate_integer(device->handle, "_GPE", NULL, &tmp); 164 if (ACPI_FAILURE(status)) 165 return -EINVAL; 166 167 xo15_sci_gpe = tmp; 168 status = acpi_install_gpe_handler(NULL, xo15_sci_gpe, 169 ACPI_GPE_EDGE_TRIGGERED, 170 xo15_sci_gpe_handler, device); 171 if (ACPI_FAILURE(status)) 172 return -ENODEV; 173 174 dev_info(&device->dev, "Initialized, GPE = 0x%lx\n", xo15_sci_gpe); 175 176 r = sysfs_create_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 177 if (r) 178 goto err_sysfs; 179 180 /* Flush queue, and enable all SCI events */ 181 process_sci_queue(); 182 olpc_ec_mask_write(EC_SCI_SRC_ALL); 183 184 acpi_enable_gpe(NULL, xo15_sci_gpe); 185 186 /* Enable wake-on-EC */ 187 if (device->wakeup.flags.valid) 188 device_init_wakeup(&device->dev, true); 189 190 return 0; 191 192 err_sysfs: 193 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 194 cancel_work_sync(&sci_work); 195 return r; 196 } 197 198 static int xo15_sci_remove(struct acpi_device *device, int type) 199 { 200 acpi_disable_gpe(NULL, xo15_sci_gpe); 201 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 202 cancel_work_sync(&sci_work); 203 sysfs_remove_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 204 return 0; 205 } 206 207 static int xo15_sci_resume(struct device *dev) 208 { 209 /* Enable all EC events */ 210 olpc_ec_mask_write(EC_SCI_SRC_ALL); 211 212 /* Power/battery status might have changed */ 213 battery_status_changed(); 214 ac_status_changed(); 215 216 return 0; 217 } 218 219 static SIMPLE_DEV_PM_OPS(xo15_sci_pm, NULL, xo15_sci_resume); 220 221 static const struct acpi_device_id xo15_sci_device_ids[] = { 222 {"XO15EC", 0}, 223 {"", 0}, 224 }; 225 226 static struct acpi_driver xo15_sci_drv = { 227 .name = DRV_NAME, 228 .class = XO15_SCI_CLASS, 229 .ids = xo15_sci_device_ids, 230 .ops = { 231 .add = xo15_sci_add, 232 .remove = xo15_sci_remove, 233 }, 234 .drv.pm = &xo15_sci_pm, 235 }; 236 237 static int __init xo15_sci_init(void) 238 { 239 return acpi_bus_register_driver(&xo15_sci_drv); 240 } 241 device_initcall(xo15_sci_init); 242