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 17 #include <acpi/acpi_bus.h> 18 #include <acpi/acpi_drivers.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 28 static void battery_status_changed(void) 29 { 30 struct power_supply *psy = power_supply_get_by_name("olpc-battery"); 31 32 if (psy) { 33 power_supply_changed(psy); 34 put_device(psy->dev); 35 } 36 } 37 38 static void ac_status_changed(void) 39 { 40 struct power_supply *psy = power_supply_get_by_name("olpc-ac"); 41 42 if (psy) { 43 power_supply_changed(psy); 44 put_device(psy->dev); 45 } 46 } 47 48 static void process_sci_queue(void) 49 { 50 u16 data; 51 int r; 52 53 do { 54 r = olpc_ec_sci_query(&data); 55 if (r || !data) 56 break; 57 58 pr_debug(PFX "SCI 0x%x received\n", data); 59 60 switch (data) { 61 case EC_SCI_SRC_BATERR: 62 case EC_SCI_SRC_BATSOC: 63 case EC_SCI_SRC_BATTERY: 64 case EC_SCI_SRC_BATCRIT: 65 battery_status_changed(); 66 break; 67 case EC_SCI_SRC_ACPWR: 68 ac_status_changed(); 69 break; 70 } 71 } while (data); 72 73 if (r) 74 pr_err(PFX "Failed to clear SCI queue"); 75 } 76 77 static void process_sci_queue_work(struct work_struct *work) 78 { 79 process_sci_queue(); 80 } 81 82 static DECLARE_WORK(sci_work, process_sci_queue_work); 83 84 static u32 xo15_sci_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context) 85 { 86 schedule_work(&sci_work); 87 return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; 88 } 89 90 static int xo15_sci_add(struct acpi_device *device) 91 { 92 unsigned long long tmp; 93 acpi_status status; 94 95 if (!device) 96 return -EINVAL; 97 98 strcpy(acpi_device_name(device), XO15_SCI_DEVICE_NAME); 99 strcpy(acpi_device_class(device), XO15_SCI_CLASS); 100 101 /* Get GPE bit assignment (EC events). */ 102 status = acpi_evaluate_integer(device->handle, "_GPE", NULL, &tmp); 103 if (ACPI_FAILURE(status)) 104 return -EINVAL; 105 106 xo15_sci_gpe = tmp; 107 status = acpi_install_gpe_handler(NULL, xo15_sci_gpe, 108 ACPI_GPE_EDGE_TRIGGERED, 109 xo15_sci_gpe_handler, device); 110 if (ACPI_FAILURE(status)) 111 return -ENODEV; 112 113 dev_info(&device->dev, "Initialized, GPE = 0x%lx\n", xo15_sci_gpe); 114 115 /* Flush queue, and enable all SCI events */ 116 process_sci_queue(); 117 olpc_ec_mask_write(EC_SCI_SRC_ALL); 118 119 acpi_enable_gpe(NULL, xo15_sci_gpe); 120 121 /* Enable wake-on-EC */ 122 if (device->wakeup.flags.valid) 123 device_init_wakeup(&device->dev, true); 124 125 return 0; 126 } 127 128 static int xo15_sci_remove(struct acpi_device *device, int type) 129 { 130 acpi_disable_gpe(NULL, xo15_sci_gpe); 131 acpi_remove_gpe_handler(NULL, xo15_sci_gpe, xo15_sci_gpe_handler); 132 cancel_work_sync(&sci_work); 133 return 0; 134 } 135 136 static int xo15_sci_resume(struct acpi_device *device) 137 { 138 /* Enable all EC events */ 139 olpc_ec_mask_write(EC_SCI_SRC_ALL); 140 141 /* Power/battery status might have changed */ 142 battery_status_changed(); 143 ac_status_changed(); 144 145 return 0; 146 } 147 148 static const struct acpi_device_id xo15_sci_device_ids[] = { 149 {"XO15EC", 0}, 150 {"", 0}, 151 }; 152 153 static struct acpi_driver xo15_sci_drv = { 154 .name = DRV_NAME, 155 .class = XO15_SCI_CLASS, 156 .ids = xo15_sci_device_ids, 157 .ops = { 158 .add = xo15_sci_add, 159 .remove = xo15_sci_remove, 160 .resume = xo15_sci_resume, 161 }, 162 }; 163 164 static int __init xo15_sci_init(void) 165 { 166 return acpi_bus_register_driver(&xo15_sci_drv); 167 } 168 device_initcall(xo15_sci_init); 169