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