linux-stable/drivers/input/serio/hyperv-keyboard.c
Guenter Roeck f20b161f59 Input: serio - drop unnecessary calls to device_init_wakeup
Calling device_init_wakeup in the remove function is unnecessary since the
device is going away, and thus won't be able to cause any wakeups under any
circumstances. Besides, the driver cleanup code already handles the
necessary cleanup.

Similarly, disabling wakeup in the probe error path is unnecessary, as is
disabling wakeup in the probe function in the first place.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-01-21 23:53:32 -08:00

441 lines
10 KiB
C

/*
* Copyright (c) 2013, Microsoft Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/completion.h>
#include <linux/hyperv.h>
#include <linux/serio.h>
#include <linux/slab.h>
/*
* Current version 1.0
*
*/
#define SYNTH_KBD_VERSION_MAJOR 1
#define SYNTH_KBD_VERSION_MINOR 0
#define SYNTH_KBD_VERSION (SYNTH_KBD_VERSION_MINOR | \
(SYNTH_KBD_VERSION_MAJOR << 16))
/*
* Message types in the synthetic input protocol
*/
enum synth_kbd_msg_type {
SYNTH_KBD_PROTOCOL_REQUEST = 1,
SYNTH_KBD_PROTOCOL_RESPONSE = 2,
SYNTH_KBD_EVENT = 3,
SYNTH_KBD_LED_INDICATORS = 4,
};
/*
* Basic message structures.
*/
struct synth_kbd_msg_hdr {
__le32 type;
};
struct synth_kbd_msg {
struct synth_kbd_msg_hdr header;
char data[]; /* Enclosed message */
};
union synth_kbd_version {
__le32 version;
};
/*
* Protocol messages
*/
struct synth_kbd_protocol_request {
struct synth_kbd_msg_hdr header;
union synth_kbd_version version_requested;
};
#define PROTOCOL_ACCEPTED BIT(0)
struct synth_kbd_protocol_response {
struct synth_kbd_msg_hdr header;
__le32 proto_status;
};
#define IS_UNICODE BIT(0)
#define IS_BREAK BIT(1)
#define IS_E0 BIT(2)
#define IS_E1 BIT(3)
struct synth_kbd_keystroke {
struct synth_kbd_msg_hdr header;
__le16 make_code;
__le16 reserved0;
__le32 info; /* Additional information */
};
#define HK_MAXIMUM_MESSAGE_SIZE 256
#define KBD_VSC_SEND_RING_BUFFER_SIZE (10 * PAGE_SIZE)
#define KBD_VSC_RECV_RING_BUFFER_SIZE (10 * PAGE_SIZE)
#define XTKBD_EMUL0 0xe0
#define XTKBD_EMUL1 0xe1
#define XTKBD_RELEASE 0x80
/*
* Represents a keyboard device
*/
struct hv_kbd_dev {
struct hv_device *hv_dev;
struct serio *hv_serio;
struct synth_kbd_protocol_request protocol_req;
struct synth_kbd_protocol_response protocol_resp;
/* Synchronize the request/response if needed */
struct completion wait_event;
spinlock_t lock; /* protects 'started' field */
bool started;
};
static void hv_kbd_on_receive(struct hv_device *hv_dev,
struct synth_kbd_msg *msg, u32 msg_length)
{
struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
struct synth_kbd_keystroke *ks_msg;
unsigned long flags;
u32 msg_type = __le32_to_cpu(msg->header.type);
u32 info;
u16 scan_code;
switch (msg_type) {
case SYNTH_KBD_PROTOCOL_RESPONSE:
/*
* Validate the information provided by the host.
* If the host is giving us a bogus packet,
* drop the packet (hoping the problem
* goes away).
*/
if (msg_length < sizeof(struct synth_kbd_protocol_response)) {
dev_err(&hv_dev->device,
"Illegal protocol response packet (len: %d)\n",
msg_length);
break;
}
memcpy(&kbd_dev->protocol_resp, msg,
sizeof(struct synth_kbd_protocol_response));
complete(&kbd_dev->wait_event);
break;
case SYNTH_KBD_EVENT:
/*
* Validate the information provided by the host.
* If the host is giving us a bogus packet,
* drop the packet (hoping the problem
* goes away).
*/
if (msg_length < sizeof(struct synth_kbd_keystroke)) {
dev_err(&hv_dev->device,
"Illegal keyboard event packet (len: %d)\n",
msg_length);
break;
}
ks_msg = (struct synth_kbd_keystroke *)msg;
info = __le32_to_cpu(ks_msg->info);
/*
* Inject the information through the serio interrupt.
*/
spin_lock_irqsave(&kbd_dev->lock, flags);
if (kbd_dev->started) {
if (info & IS_E0)
serio_interrupt(kbd_dev->hv_serio,
XTKBD_EMUL0, 0);
if (info & IS_E1)
serio_interrupt(kbd_dev->hv_serio,
XTKBD_EMUL1, 0);
scan_code = __le16_to_cpu(ks_msg->make_code);
if (info & IS_BREAK)
scan_code |= XTKBD_RELEASE;
serio_interrupt(kbd_dev->hv_serio, scan_code, 0);
}
spin_unlock_irqrestore(&kbd_dev->lock, flags);
/*
* Only trigger a wakeup on key down, otherwise
* "echo freeze > /sys/power/state" can't really enter the
* state because the Enter-UP can trigger a wakeup at once.
*/
if (!(info & IS_BREAK))
pm_wakeup_event(&hv_dev->device, 0);
break;
default:
dev_err(&hv_dev->device,
"unhandled message type %d\n", msg_type);
}
}
static void hv_kbd_handle_received_packet(struct hv_device *hv_dev,
struct vmpacket_descriptor *desc,
u32 bytes_recvd,
u64 req_id)
{
struct synth_kbd_msg *msg;
u32 msg_sz;
switch (desc->type) {
case VM_PKT_COMP:
break;
case VM_PKT_DATA_INBAND:
/*
* We have a packet that has "inband" data. The API used
* for retrieving the packet guarantees that the complete
* packet is read. So, minimally, we should be able to
* parse the payload header safely (assuming that the host
* can be trusted. Trusting the host seems to be a
* reasonable assumption because in a virtualized
* environment there is not whole lot you can do if you
* don't trust the host.
*
* Nonetheless, let us validate if the host can be trusted
* (in a trivial way). The interesting aspect of this
* validation is how do you recover if we discover that the
* host is not to be trusted? Simply dropping the packet, I
* don't think is an appropriate recovery. In the interest
* of failing fast, it may be better to crash the guest.
* For now, I will just drop the packet!
*/
msg_sz = bytes_recvd - (desc->offset8 << 3);
if (msg_sz <= sizeof(struct synth_kbd_msg_hdr)) {
/*
* Drop the packet and hope
* the problem magically goes away.
*/
dev_err(&hv_dev->device,
"Illegal packet (type: %d, tid: %llx, size: %d)\n",
desc->type, req_id, msg_sz);
break;
}
msg = (void *)desc + (desc->offset8 << 3);
hv_kbd_on_receive(hv_dev, msg, msg_sz);
break;
default:
dev_err(&hv_dev->device,
"unhandled packet type %d, tid %llx len %d\n",
desc->type, req_id, bytes_recvd);
break;
}
}
static void hv_kbd_on_channel_callback(void *context)
{
struct hv_device *hv_dev = context;
void *buffer;
int bufferlen = 0x100; /* Start with sensible size */
u32 bytes_recvd;
u64 req_id;
int error;
buffer = kmalloc(bufferlen, GFP_ATOMIC);
if (!buffer)
return;
while (1) {
error = vmbus_recvpacket_raw(hv_dev->channel, buffer, bufferlen,
&bytes_recvd, &req_id);
switch (error) {
case 0:
if (bytes_recvd == 0) {
kfree(buffer);
return;
}
hv_kbd_handle_received_packet(hv_dev, buffer,
bytes_recvd, req_id);
break;
case -ENOBUFS:
kfree(buffer);
/* Handle large packet */
bufferlen = bytes_recvd;
buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
if (!buffer)
return;
break;
}
}
}
static int hv_kbd_connect_to_vsp(struct hv_device *hv_dev)
{
struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
struct synth_kbd_protocol_request *request;
struct synth_kbd_protocol_response *response;
u32 proto_status;
int error;
request = &kbd_dev->protocol_req;
memset(request, 0, sizeof(struct synth_kbd_protocol_request));
request->header.type = __cpu_to_le32(SYNTH_KBD_PROTOCOL_REQUEST);
request->version_requested.version = __cpu_to_le32(SYNTH_KBD_VERSION);
error = vmbus_sendpacket(hv_dev->channel, request,
sizeof(struct synth_kbd_protocol_request),
(unsigned long)request,
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (error)
return error;
if (!wait_for_completion_timeout(&kbd_dev->wait_event, 10 * HZ))
return -ETIMEDOUT;
response = &kbd_dev->protocol_resp;
proto_status = __le32_to_cpu(response->proto_status);
if (!(proto_status & PROTOCOL_ACCEPTED)) {
dev_err(&hv_dev->device,
"synth_kbd protocol request failed (version %d)\n",
SYNTH_KBD_VERSION);
return -ENODEV;
}
return 0;
}
static int hv_kbd_start(struct serio *serio)
{
struct hv_kbd_dev *kbd_dev = serio->port_data;
unsigned long flags;
spin_lock_irqsave(&kbd_dev->lock, flags);
kbd_dev->started = true;
spin_unlock_irqrestore(&kbd_dev->lock, flags);
return 0;
}
static void hv_kbd_stop(struct serio *serio)
{
struct hv_kbd_dev *kbd_dev = serio->port_data;
unsigned long flags;
spin_lock_irqsave(&kbd_dev->lock, flags);
kbd_dev->started = false;
spin_unlock_irqrestore(&kbd_dev->lock, flags);
}
static int hv_kbd_probe(struct hv_device *hv_dev,
const struct hv_vmbus_device_id *dev_id)
{
struct hv_kbd_dev *kbd_dev;
struct serio *hv_serio;
int error;
kbd_dev = kzalloc(sizeof(struct hv_kbd_dev), GFP_KERNEL);
hv_serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
if (!kbd_dev || !hv_serio) {
error = -ENOMEM;
goto err_free_mem;
}
kbd_dev->hv_dev = hv_dev;
kbd_dev->hv_serio = hv_serio;
spin_lock_init(&kbd_dev->lock);
init_completion(&kbd_dev->wait_event);
hv_set_drvdata(hv_dev, kbd_dev);
hv_serio->dev.parent = &hv_dev->device;
hv_serio->id.type = SERIO_8042_XL;
hv_serio->port_data = kbd_dev;
strlcpy(hv_serio->name, dev_name(&hv_dev->device),
sizeof(hv_serio->name));
strlcpy(hv_serio->phys, dev_name(&hv_dev->device),
sizeof(hv_serio->phys));
hv_serio->start = hv_kbd_start;
hv_serio->stop = hv_kbd_stop;
error = vmbus_open(hv_dev->channel,
KBD_VSC_SEND_RING_BUFFER_SIZE,
KBD_VSC_RECV_RING_BUFFER_SIZE,
NULL, 0,
hv_kbd_on_channel_callback,
hv_dev);
if (error)
goto err_free_mem;
error = hv_kbd_connect_to_vsp(hv_dev);
if (error)
goto err_close_vmbus;
serio_register_port(kbd_dev->hv_serio);
device_init_wakeup(&hv_dev->device, true);
return 0;
err_close_vmbus:
vmbus_close(hv_dev->channel);
err_free_mem:
kfree(hv_serio);
kfree(kbd_dev);
return error;
}
static int hv_kbd_remove(struct hv_device *hv_dev)
{
struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
serio_unregister_port(kbd_dev->hv_serio);
vmbus_close(hv_dev->channel);
kfree(kbd_dev);
hv_set_drvdata(hv_dev, NULL);
return 0;
}
static const struct hv_vmbus_device_id id_table[] = {
/* Keyboard guid */
{ HV_KBD_GUID, },
{ },
};
MODULE_DEVICE_TABLE(vmbus, id_table);
static struct hv_driver hv_kbd_drv = {
.name = KBUILD_MODNAME,
.id_table = id_table,
.probe = hv_kbd_probe,
.remove = hv_kbd_remove,
};
static int __init hv_kbd_init(void)
{
return vmbus_driver_register(&hv_kbd_drv);
}
static void __exit hv_kbd_exit(void)
{
vmbus_driver_unregister(&hv_kbd_drv);
}
MODULE_LICENSE("GPL");
module_init(hv_kbd_init);
module_exit(hv_kbd_exit);