diff options
Diffstat (limited to 'drivers/input/mouse/vmmouse.c')
| -rw-r--r-- | drivers/input/mouse/vmmouse.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c new file mode 100644 index 000000000..1ae5c1ef3 --- /dev/null +++ b/drivers/input/mouse/vmmouse.c @@ -0,0 +1,489 @@ +/* + * Driver for Virtual PS/2 Mouse on VMware and QEMU hypervisors. + * + * Copyright (C) 2014, VMware, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * Twin device code is hugely inspired by the ALPS driver. + * Authors: + * Dmitry Torokhov <dmitry.torokhov@gmail.com> + * Thomas Hellstrom <thellstrom@vmware.com> + */ + +#include <linux/input.h> +#include <linux/serio.h> +#include <linux/libps2.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <asm/hypervisor.h> + +#include "psmouse.h" +#include "vmmouse.h" + +#define VMMOUSE_PROTO_MAGIC 0x564D5868U +#define VMMOUSE_PROTO_PORT 0x5658 + +/* + * Main commands supported by the vmmouse hypervisor port. + */ +#define VMMOUSE_PROTO_CMD_GETVERSION 10 +#define VMMOUSE_PROTO_CMD_ABSPOINTER_DATA 39 +#define VMMOUSE_PROTO_CMD_ABSPOINTER_STATUS 40 +#define VMMOUSE_PROTO_CMD_ABSPOINTER_COMMAND 41 +#define VMMOUSE_PROTO_CMD_ABSPOINTER_RESTRICT 86 + +/* + * Subcommands for VMMOUSE_PROTO_CMD_ABSPOINTER_COMMAND + */ +#define VMMOUSE_CMD_ENABLE 0x45414552U +#define VMMOUSE_CMD_DISABLE 0x000000f5U +#define VMMOUSE_CMD_REQUEST_RELATIVE 0x4c455252U +#define VMMOUSE_CMD_REQUEST_ABSOLUTE 0x53424152U + +#define VMMOUSE_ERROR 0xffff0000U + +#define VMMOUSE_VERSION_ID 0x3442554aU + +#define VMMOUSE_RELATIVE_PACKET 0x00010000U + +#define VMMOUSE_LEFT_BUTTON 0x20 +#define VMMOUSE_RIGHT_BUTTON 0x10 +#define VMMOUSE_MIDDLE_BUTTON 0x08 + +/* + * VMMouse Restrict command + */ +#define VMMOUSE_RESTRICT_ANY 0x00 +#define VMMOUSE_RESTRICT_CPL0 0x01 +#define VMMOUSE_RESTRICT_IOPL 0x02 + +#define VMMOUSE_MAX_X 0xFFFF +#define VMMOUSE_MAX_Y 0xFFFF + +#define VMMOUSE_VENDOR "VMware" +#define VMMOUSE_NAME "VMMouse" + +/** + * struct vmmouse_data - private data structure for the vmmouse driver + * + * @abs_dev: "Absolute" device used to report absolute mouse movement. + * @phys: Physical path for the absolute device. + * @dev_name: Name attribute name for the absolute device. + */ +struct vmmouse_data { + struct input_dev *abs_dev; + char phys[32]; + char dev_name[128]; +}; + +/** + * Hypervisor-specific bi-directional communication channel + * implementing the vmmouse protocol. Should never execute on + * bare metal hardware. + */ +#define VMMOUSE_CMD(cmd, in1, out1, out2, out3, out4) \ +({ \ + unsigned long __dummy1, __dummy2; \ + __asm__ __volatile__ ("inl %%dx" : \ + "=a"(out1), \ + "=b"(out2), \ + "=c"(out3), \ + "=d"(out4), \ + "=S"(__dummy1), \ + "=D"(__dummy2) : \ + "a"(VMMOUSE_PROTO_MAGIC), \ + "b"(in1), \ + "c"(VMMOUSE_PROTO_CMD_##cmd), \ + "d"(VMMOUSE_PROTO_PORT) : \ + "memory"); \ +}) + +/** + * vmmouse_report_button - report button state on the correct input device + * + * @psmouse: Pointer to the psmouse struct + * @abs_dev: The absolute input device + * @rel_dev: The relative input device + * @pref_dev: The preferred device for reporting + * @code: Button code + * @value: Button value + * + * Report @value and @code on @pref_dev, unless the button is already + * pressed on the other device, in which case the state is reported on that + * device. + */ +static void vmmouse_report_button(struct psmouse *psmouse, + struct input_dev *abs_dev, + struct input_dev *rel_dev, + struct input_dev *pref_dev, + unsigned int code, int value) +{ + if (test_bit(code, abs_dev->key)) + pref_dev = abs_dev; + else if (test_bit(code, rel_dev->key)) + pref_dev = rel_dev; + + input_report_key(pref_dev, code, value); +} + +/** + * vmmouse_report_events - process events on the vmmouse communications channel + * + * @psmouse: Pointer to the psmouse struct + * + * This function pulls events from the vmmouse communications channel and + * reports them on the correct (absolute or relative) input device. When the + * communications channel is drained, or if we've processed more than 255 + * psmouse commands, the function returns PSMOUSE_FULL_PACKET. If there is a + * host- or synchronization error, the function returns PSMOUSE_BAD_DATA in + * the hope that the caller will reset the communications channel. + */ +static psmouse_ret_t vmmouse_report_events(struct psmouse *psmouse) +{ + struct input_dev *rel_dev = psmouse->dev; + struct vmmouse_data *priv = psmouse->private; + struct input_dev *abs_dev = priv->abs_dev; + struct input_dev *pref_dev; + u32 status, x, y, z; + u32 dummy1, dummy2, dummy3; + unsigned int queue_length; + unsigned int count = 255; + + while (count--) { + /* See if we have motion data. */ + VMMOUSE_CMD(ABSPOINTER_STATUS, 0, + status, dummy1, dummy2, dummy3); + if ((status & VMMOUSE_ERROR) == VMMOUSE_ERROR) { + psmouse_err(psmouse, "failed to fetch status data\n"); + /* + * After a few attempts this will result in + * reconnect. + */ + return PSMOUSE_BAD_DATA; + } + + queue_length = status & 0xffff; + if (queue_length == 0) + break; + + if (queue_length % 4) { + psmouse_err(psmouse, "invalid queue length\n"); + return PSMOUSE_BAD_DATA; + } + + /* Now get it */ + VMMOUSE_CMD(ABSPOINTER_DATA, 4, status, x, y, z); + + /* + * And report what we've got. Prefer to report button + * events on the same device where we report motion events. + * This doesn't work well with the mouse wheel, though. See + * below. Ideally we would want to report that on the + * preferred device as well. + */ + if (status & VMMOUSE_RELATIVE_PACKET) { + pref_dev = rel_dev; + input_report_rel(rel_dev, REL_X, (s32)x); + input_report_rel(rel_dev, REL_Y, -(s32)y); + } else { + pref_dev = abs_dev; + input_report_abs(abs_dev, ABS_X, x); + input_report_abs(abs_dev, ABS_Y, y); + } + + /* Xorg seems to ignore wheel events on absolute devices */ + input_report_rel(rel_dev, REL_WHEEL, -(s8)((u8) z)); + + vmmouse_report_button(psmouse, abs_dev, rel_dev, + pref_dev, BTN_LEFT, + status & VMMOUSE_LEFT_BUTTON); + vmmouse_report_button(psmouse, abs_dev, rel_dev, + pref_dev, BTN_RIGHT, + status & VMMOUSE_RIGHT_BUTTON); + vmmouse_report_button(psmouse, abs_dev, rel_dev, + pref_dev, BTN_MIDDLE, + status & VMMOUSE_MIDDLE_BUTTON); + input_sync(abs_dev); + input_sync(rel_dev); + } + + return PSMOUSE_FULL_PACKET; +} + +/** + * vmmouse_process_byte - process data on the ps/2 channel + * + * @psmouse: Pointer to the psmouse struct + * + * When the ps/2 channel indicates that there is vmmouse data available, + * call vmmouse channel processing. Otherwise, continue to accept bytes. If + * there is a synchronization or communication data error, return + * PSMOUSE_BAD_DATA in the hope that the caller will reset the mouse. + */ +static psmouse_ret_t vmmouse_process_byte(struct psmouse *psmouse) +{ + unsigned char *packet = psmouse->packet; + + switch (psmouse->pktcnt) { + case 1: + return (packet[0] & 0x8) == 0x8 ? + PSMOUSE_GOOD_DATA : PSMOUSE_BAD_DATA; + + case 2: + return PSMOUSE_GOOD_DATA; + + default: + return vmmouse_report_events(psmouse); + } +} + +/** + * vmmouse_disable - Disable vmmouse + * + * @psmouse: Pointer to the psmouse struct + * + * Tries to disable vmmouse mode. + */ +static void vmmouse_disable(struct psmouse *psmouse) +{ + u32 status; + u32 dummy1, dummy2, dummy3, dummy4; + + VMMOUSE_CMD(ABSPOINTER_COMMAND, VMMOUSE_CMD_DISABLE, + dummy1, dummy2, dummy3, dummy4); + + VMMOUSE_CMD(ABSPOINTER_STATUS, 0, + status, dummy1, dummy2, dummy3); + + if ((status & VMMOUSE_ERROR) != VMMOUSE_ERROR) + psmouse_warn(psmouse, "failed to disable vmmouse device\n"); +} + +/** + * vmmouse_enable - Enable vmmouse and request absolute mode. + * + * @psmouse: Pointer to the psmouse struct + * + * Tries to enable vmmouse mode. Performs basic checks and requests + * absolute vmmouse mode. + * Returns 0 on success, -ENODEV on failure. + */ +static int vmmouse_enable(struct psmouse *psmouse) +{ + u32 status, version; + u32 dummy1, dummy2, dummy3, dummy4; + + /* + * Try enabling the device. If successful, we should be able to + * read valid version ID back from it. + */ + VMMOUSE_CMD(ABSPOINTER_COMMAND, VMMOUSE_CMD_ENABLE, + dummy1, dummy2, dummy3, dummy4); + + /* + * See if version ID can be retrieved. + */ + VMMOUSE_CMD(ABSPOINTER_STATUS, 0, status, dummy1, dummy2, dummy3); + if ((status & 0x0000ffff) == 0) { + psmouse_dbg(psmouse, "empty flags - assuming no device\n"); + return -ENXIO; + } + + VMMOUSE_CMD(ABSPOINTER_DATA, 1 /* single item */, + version, dummy1, dummy2, dummy3); + if (version != VMMOUSE_VERSION_ID) { + psmouse_dbg(psmouse, "Unexpected version value: %u vs %u\n", + (unsigned) version, VMMOUSE_VERSION_ID); + vmmouse_disable(psmouse); + return -ENXIO; + } + + /* + * Restrict ioport access, if possible. + */ + VMMOUSE_CMD(ABSPOINTER_RESTRICT, VMMOUSE_RESTRICT_CPL0, + dummy1, dummy2, dummy3, dummy4); + + VMMOUSE_CMD(ABSPOINTER_COMMAND, VMMOUSE_CMD_REQUEST_ABSOLUTE, + dummy1, dummy2, dummy3, dummy4); + + return 0; +} + +/* + * Array of supported hypervisors. + */ +static enum x86_hypervisor_type vmmouse_supported_hypervisors[] = { + X86_HYPER_VMWARE, + X86_HYPER_KVM, +}; + +/** + * vmmouse_check_hypervisor - Check if we're running on a supported hypervisor + */ +static bool vmmouse_check_hypervisor(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(vmmouse_supported_hypervisors); i++) + if (vmmouse_supported_hypervisors[i] == x86_hyper_type) + return true; + + return false; +} + +/** + * vmmouse_detect - Probe whether vmmouse is available + * + * @psmouse: Pointer to the psmouse struct + * @set_properties: Whether to set psmouse name and vendor + * + * Returns 0 if vmmouse channel is available. Negative error code if not. + */ +int vmmouse_detect(struct psmouse *psmouse, bool set_properties) +{ + u32 response, version, dummy1, dummy2; + + if (!vmmouse_check_hypervisor()) { + psmouse_dbg(psmouse, + "VMMouse not running on supported hypervisor.\n"); + return -ENXIO; + } + + /* Check if the device is present */ + response = ~VMMOUSE_PROTO_MAGIC; + VMMOUSE_CMD(GETVERSION, 0, version, response, dummy1, dummy2); + if (response != VMMOUSE_PROTO_MAGIC || version == 0xffffffffU) + return -ENXIO; + + if (set_properties) { + psmouse->vendor = VMMOUSE_VENDOR; + psmouse->name = VMMOUSE_NAME; + psmouse->model = version; + } + + return 0; +} + +/** + * vmmouse_disconnect - Take down vmmouse driver + * + * @psmouse: Pointer to the psmouse struct + * + * Takes down vmmouse driver and frees resources set up in vmmouse_init(). + */ +static void vmmouse_disconnect(struct psmouse *psmouse) +{ + struct vmmouse_data *priv = psmouse->private; + + vmmouse_disable(psmouse); + psmouse_reset(psmouse); + input_unregister_device(priv->abs_dev); + kfree(priv); +} + +/** + * vmmouse_reconnect - Reset the ps/2 - and vmmouse connections + * + * @psmouse: Pointer to the psmouse struct + * + * Attempts to reset the mouse connections. Returns 0 on success and + * -1 on failure. + */ +static int vmmouse_reconnect(struct psmouse *psmouse) +{ + int error; + + psmouse_reset(psmouse); + vmmouse_disable(psmouse); + error = vmmouse_enable(psmouse); + if (error) { + psmouse_err(psmouse, + "Unable to re-enable mouse when reconnecting, err: %d\n", + error); + return error; + } + + return 0; +} + +/** + * vmmouse_init - Initialize the vmmouse driver + * + * @psmouse: Pointer to the psmouse struct + * + * Requests the device and tries to enable vmmouse mode. + * If successful, sets up the input device for relative movement events. + * It also allocates another input device and sets it up for absolute motion + * events. Returns 0 on success and -1 on failure. + */ +int vmmouse_init(struct psmouse *psmouse) +{ + struct vmmouse_data *priv; + struct input_dev *rel_dev = psmouse->dev, *abs_dev; + int error; + + psmouse_reset(psmouse); + error = vmmouse_enable(psmouse); + if (error) + return error; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + abs_dev = input_allocate_device(); + if (!priv || !abs_dev) { + error = -ENOMEM; + goto init_fail; + } + + priv->abs_dev = abs_dev; + psmouse->private = priv; + + /* Set up and register absolute device */ + snprintf(priv->phys, sizeof(priv->phys), "%s/input1", + psmouse->ps2dev.serio->phys); + + /* Mimic name setup for relative device in psmouse-base.c */ + snprintf(priv->dev_name, sizeof(priv->dev_name), "%s %s %s", + VMMOUSE_PSNAME, VMMOUSE_VENDOR, VMMOUSE_NAME); + abs_dev->phys = priv->phys; + abs_dev->name = priv->dev_name; + abs_dev->id.bustype = BUS_I8042; + abs_dev->id.vendor = 0x0002; + abs_dev->id.product = PSMOUSE_VMMOUSE; + abs_dev->id.version = psmouse->model; + abs_dev->dev.parent = &psmouse->ps2dev.serio->dev; + + /* Set absolute device capabilities */ + input_set_capability(abs_dev, EV_KEY, BTN_LEFT); + input_set_capability(abs_dev, EV_KEY, BTN_RIGHT); + input_set_capability(abs_dev, EV_KEY, BTN_MIDDLE); + input_set_capability(abs_dev, EV_ABS, ABS_X); + input_set_capability(abs_dev, EV_ABS, ABS_Y); + input_set_abs_params(abs_dev, ABS_X, 0, VMMOUSE_MAX_X, 0, 0); + input_set_abs_params(abs_dev, ABS_Y, 0, VMMOUSE_MAX_Y, 0, 0); + + error = input_register_device(priv->abs_dev); + if (error) + goto init_fail; + + /* Add wheel capability to the relative device */ + input_set_capability(rel_dev, EV_REL, REL_WHEEL); + + psmouse->protocol_handler = vmmouse_process_byte; + psmouse->disconnect = vmmouse_disconnect; + psmouse->reconnect = vmmouse_reconnect; + + return 0; + +init_fail: + vmmouse_disable(psmouse); + psmouse_reset(psmouse); + input_free_device(abs_dev); + kfree(priv); + psmouse->private = NULL; + + return error; +} |