1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Support for OLPC XO-1.5 System Control Interrupts (SCI) 4 * 5 * Copyright (C) 2009-2010 One Laptop per Child 6 */ 7 8 #include <linux/device.h> 9 #include <linux/slab.h> 10 #include <linux/string.h> 11 #include <linux/workqueue.h> 12 #include <linux/power_supply.h> 13 #include <linux/olpc-ec.h> 14 15 #include <linux/acpi.h> 16 #include <asm/olpc.h> 17 18 #define DRV_NAME "olpc-xo15-sci" 19 #define PFX DRV_NAME ": " 20 #define XO15_SCI_CLASS DRV_NAME 21 #define XO15_SCI_DEVICE_NAME "OLPC XO-1.5 SCI" 22 23 static unsigned long xo15_sci_gpe; 24 static bool lid_wake_on_close; 25 26 /* 27 * The normal ACPI LID wakeup behavior is wake-on-open, but not 28 * wake-on-close. This is implemented as standard by the XO-1.5 DSDT. 29 * 30 * We provide here a sysfs attribute that will additionally enable 31 * wake-on-close behavior. This is useful (e.g.) when we opportunistically 32 * suspend with the display running; if the lid is then closed, we want to 33 * wake up to turn the display off. 34 * 35 * This is controlled through a custom method in the XO-1.5 DSDT. 36 */ 37 static int set_lid_wake_behavior(bool wake_on_close) 38 { 39 acpi_status status; 40 41 status = acpi_execute_simple_method(NULL, "\\_SB.PCI0.LID.LIDW", wake_on_close); 42 if (ACPI_FAILURE(status)) { 43 pr_warn(PFX "failed to set lid behavior\n"); 44 return 1; 45 } 46 47 lid_wake_on_close = wake_on_close; 48 49 return 0; 50 } 51 52 static ssize_t 53 lid_wake_on_close_show(struct kobject *s, struct kobj_attribute *attr, char *buf) 54 { 55 return sprintf(buf, "%u\n", lid_wake_on_close); 56 } 57 58 static ssize_t lid_wake_on_close_store(struct kobject *s, 59 struct kobj_attribute *attr, 60 const char *buf, size_t n) 61 { 62 unsigned int val; 63 64 if (sscanf(buf, "%u", &val) != 1) 65 return -EINVAL; 66 67 set_lid_wake_behavior(!!val); 68 69 return n; 70 } 71 72 static struct kobj_attribute lid_wake_on_close_attr = 73 __ATTR(lid_wake_on_close, 0644, 74 lid_wake_on_close_show, 75 lid_wake_on_close_store); 76 77 static void battery_status_changed(void) 78 { 79 struct power_supply *psy = power_supply_get_by_name("olpc_battery"); 80 81 if (psy) { 82 power_supply_changed(psy); 83 power_supply_put(psy); 84 } 85 } 86 87 static void ac_status_changed(void) 88 { 89 struct power_supply *psy = power_supply_get_by_name("olpc_ac"); 90 91 if (psy) { 92 power_supply_changed(psy); 93 power_supply_put(psy); 94 } 95 } 96 97 static void process_sci_queue(void) 98 { 99 u16 data; 100 int r; 101 102 do { 103 r = olpc_ec_sci_query(&data); 104 if (r || !data) 105 break; 106 107 pr_debug(PFX "SCI 0x%x received\n", data); 108 109 switch (data) { 110 case EC_SCI_SRC_BATERR: 111 case EC_SCI_SRC_BATSOC: 112 case EC_SCI_SRC_BATTERY: 113 case EC_SCI_SRC_BATCRIT: 114 battery_status_changed(); 115 break; 116 case EC_SCI_SRC_ACPWR: 117 ac_status_changed(); 118 break; 119 } 120 } while (data); 121 122 if (r) 123 pr_err(PFX "Failed to clear SCI queue"); 124 } 125 126 static void process_sci_queue_work(struct work_struct *work) 127 { 128 process_sci_queue(); 129 } 130 131 static DECLARE_WORK(sci_work, process_sci_queue_work); 132 133 static u32 xo15_sci_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context) 134 { 135 schedule_work(&sci_work); 136 return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; 137 } 138 139 static int xo15_sci_add(struct acpi_device *device) 140 { 141 unsigned long long tmp; 142 acpi_status status; 143 int r; 144 145 if (!device) 146 return -EINVAL; 147 148 strscpy(acpi_device_name(device), XO15_SCI_DEVICE_NAME); 149 strscpy(acpi_device_class(device), XO15_SCI_CLASS); 150 151 /* Get GPE bit assignment (EC events). */ 152 status = acpi_evaluate_integer(device->handle, "_GPE", NULL, &tmp); 153 if (ACPI_FAILURE(status)) 154 return -EINVAL; 155 156 xo15_sci_gpe = tmp; 157 status = acpi_install_gpe_handler(NULL, xo15_sci_gpe, 158 ACPI_GPE_EDGE_TRIGGERED, 159 xo15_sci_gpe_handler, device); 160 if (ACPI_FAILURE(status)) 161 return -ENODEV; 162 163 dev_info(&device->dev, "Initialized, GPE = 0x%lx\n", xo15_sci_gpe); 164 165 r = sysfs_create_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 166 if (r) 167 goto err_sysfs; 168 169 /* Flush queue, and enable all SCI events */ 170 process_sci_queue(); 171 olpc_ec_mask_write(EC_SCI_SRC_ALL); 172 173 acpi_enable_gpe(NULL, xo15_sci_gpe); 174 175 /* Enable wake-on-EC */ 176 if (device->wakeup.flags.valid) 177 device_init_wakeup(&device->dev, true); 178 179 return 0; 180 181 err_sysfs: 182 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 183 cancel_work_sync(&sci_work); 184 return r; 185 } 186 187 static void xo15_sci_remove(struct acpi_device *device) 188 { 189 acpi_disable_gpe(NULL, xo15_sci_gpe); 190 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 191 cancel_work_sync(&sci_work); 192 sysfs_remove_file(&device->dev.kobj, &lid_wake_on_close_attr.attr); 193 } 194 195 #ifdef CONFIG_PM_SLEEP 196 static int xo15_sci_resume(struct device *dev) 197 { 198 /* Enable all EC events */ 199 olpc_ec_mask_write(EC_SCI_SRC_ALL); 200 201 /* Power/battery status might have changed */ 202 battery_status_changed(); 203 ac_status_changed(); 204 205 return 0; 206 } 207 #endif 208 209 static SIMPLE_DEV_PM_OPS(xo15_sci_pm, NULL, xo15_sci_resume); 210 211 static const struct acpi_device_id xo15_sci_device_ids[] = { 212 {"XO15EC", 0}, 213 {"", 0}, 214 }; 215 216 static struct acpi_driver xo15_sci_drv = { 217 .name = DRV_NAME, 218 .class = XO15_SCI_CLASS, 219 .ids = xo15_sci_device_ids, 220 .ops = { 221 .add = xo15_sci_add, 222 .remove = xo15_sci_remove, 223 }, 224 .drv.pm = &xo15_sci_pm, 225 }; 226 227 static int __init xo15_sci_init(void) 228 { 229 return acpi_bus_register_driver(&xo15_sci_drv); 230 } 231 device_initcall(xo15_sci_init); 232