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
battery_status_changed(void)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
ac_status_changed(void)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
process_sci_queue(void)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
process_sci_queue_work(struct work_struct * work)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
xo15_sci_gpe_handler(acpi_handle gpe_device,u32 gpe,void * context)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
xo15_sci_add(struct acpi_device * device)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
xo15_sci_remove(struct acpi_device * device,int type)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
xo15_sci_resume(struct acpi_device * device)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
xo15_sci_init(void)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