* Copyright (c) 2017 Microsoft Corp.

/* $NetBSD: hvkbd.c,v 1.9 2021/08/07 16:19:11 thorpej Exp $ */

/*-
* Copyright (c) 2017 Microsoft Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD: head/sys/dev/hyperv/input/hv_kbd.c 317821 2017-05-05 03:28:30Z sephe $
* $FreeBSD: head/sys/dev/hyperv/input/hv_kbdc.c 320490 2017-06-30 03:01:22Z sephe $
* $FreeBSD: head/sys/dev/hyperv/input/hv_kbdc.h 316515 2017-04-05 05:01:23Z sephe $
*/

#ifdef _KERNEL_OPT
#include "opt_pckbd_layout.h"
#include "opt_wsdisplay_compat.h"
#endif /* _KERNEL_OPT */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: hvkbd.c,v 1.9 2021/08/07 16:19:11 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/kmem.h>
#include <sys/module.h>
#include <sys/pmf.h>
#include <sys/proc.h>
#include <sys/queue.h>

#include <dev/hyperv/vmbusvar.h>
#include <dev/hyperv/hvkbdvar.h>

#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wskbdvar.h>
#include <dev/wscons/wsksymdef.h>
#include <dev/wscons/wsksymvar.h>
#include <dev/pckbport/wskbdmap_mfii.h>

#define HVKBD_BUFSIZE (4 * PAGE_SIZE)
#define HVKBD_TX_RING_SIZE (10 * PAGE_SIZE)
#define HVKBD_RX_RING_SIZE (10 * PAGE_SIZE)

#define HVKBD_VER_MAJOR (1)
#define HVKBD_VER_MINOR (0)
#define HVKBD_VERSION ((HVKBD_VER_MAJOR << 16) | HVKBD_VER_MINOR)

enum hvkbd_msg_type {
HVKBD_PROTO_REQUEST = 1,
HVKBD_PROTO_RESPONSE = 2,
HVKBD_PROTO_EVENT = 3,
HVKBD_PROTO_LED_INDICATORS = 4
};

struct hvkbd_msg_hdr {
uint32_t type;
} __packed;

struct hvkbd_proto_req {
struct hvkbd_msg_hdr hdr;
uint32_t ver;
} __packed;

struct hvkbd_proto_resp {
struct hvkbd_msg_hdr hdr;
uint32_t status;
#define RESP_STATUS_ACCEPTED __BIT(0)
} __packed;

struct keystroke {
uint16_t makecode;
uint16_t pad0;
uint32_t info;
#define KS_INFO_UNICODE __BIT(0)
#define KS_INFO_BREAK __BIT(1)
#define KS_INFO_E0 __BIT(2)
#define KS_INFO_E1 __BIT(3)
} __packed;

struct hvkbd_keystroke {
struct hvkbd_msg_hdr hdr;
struct keystroke ks;
} __packed;

struct hvkbd_keystroke_info {
LIST_ENTRY(hvkbd_keystroke_info) link;
STAILQ_ENTRY(hvkbd_keystroke_info) slink;
struct keystroke ks;
};

#define HVKBD_KEYBUF_SIZE 16

struct hvkbd_softc {
device_t sc_dev;

struct vmbus_channel *sc_chan;
void *sc_buf;

kmutex_t sc_ks_lock;
LIST_HEAD(, hvkbd_keystroke_info) sc_ks_free;
STAILQ_HEAD(, hvkbd_keystroke_info) sc_ks_queue;

int sc_enabled;
int sc_polling;
int sc_console_keyboard;
#if defined(WSDISPLAY_COMPAT_RAWKBD)
int sc_rawkbd;
#endif

int sc_connected;
uint32_t sc_connect_status;

device_t sc_wskbddev;
};

static int hvkbd_match(device_t, cfdata_t, void *);
static void hvkbd_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(hvkbd, sizeof(struct hvkbd_softc),
hvkbd_match, hvkbd_attach, NULL, NULL);

static int hvkbd_alloc_keybuf(struct hvkbd_softc *);
static void hvkbd_free_keybuf(struct hvkbd_softc *);

static int hvkbd_enable(void *, int);
static void hvkbd_set_leds(void *, int);
static int hvkbd_ioctl(void *, u_long, void *, int, struct lwp *);

static const struct wskbd_accessops hvkbd_accessops = {
hvkbd_enable,
hvkbd_set_leds,
hvkbd_ioctl,
};

static const struct wskbd_mapdata hvkbd_keymapdata = {
pckbd_keydesctab,
#if defined(PCKBD_LAYOUT)
PCKBD_LAYOUT,
#else
KB_US,
#endif
};

static int hvkbd_connect(struct hvkbd_softc *);
static void hvkbd_intr(void *);

static void hvkbd_cngetc(void *, u_int *, int *);
static void hvkbd_cnpollc(void *, int);

static const struct wskbd_consops hvkbd_consops = {
.getc = hvkbd_cngetc,
.pollc = hvkbd_cnpollc,
.bell = NULL,
};

static int hvkbd_is_console;

static int
hvkbd_match(device_t parent, cfdata_t cf, void *aux)
{
struct vmbus_attach_args *aa = aux;

if (memcmp(aa->aa_type, &hyperv_guid_kbd, sizeof(*aa->aa_type)) != 0)
return 0;

/* If hvkbd(4) is not console, we use pckbd(4) in Gen.1 VM. */
if (!hvkbd_is_console && hyperv_is_gen1())
return 0;

return 1;
}

static void
hvkbd_attach(device_t parent, device_t self, void *aux)
{
struct hvkbd_softc *sc = device_private(self);
struct vmbus_attach_args *aa = aux;
struct wskbddev_attach_args a;

sc->sc_dev = self;
sc->sc_chan = aa->aa_chan;

aprint_naive("\n");
aprint_normal(": Hyper-V Synthetic Keyboard\n");

mutex_init(&sc->sc_ks_lock, MUTEX_DEFAULT, IPL_TTY);
LIST_INIT(&sc->sc_ks_free);
STAILQ_INIT(&sc->sc_ks_queue);
hvkbd_alloc_keybuf(sc);

sc->sc_buf = kmem_zalloc(HVKBD_BUFSIZE, KM_SLEEP);

sc->sc_chan->ch_flags &= ~CHF_BATCHED;
if (vmbus_channel_open(sc->sc_chan,
HVKBD_TX_RING_SIZE + HVKBD_RX_RING_SIZE, NULL, 0, hvkbd_intr, sc)) {
aprint_error_dev(self, "failed to open channel\n");
goto free_buf;
}

if (hvkbd_connect(sc))
goto free_buf;

if (!pmf_device_register(self, NULL, NULL))
aprint_error_dev(self, "couldn't establish power handler\n");

sc->sc_console_keyboard = hvkbd_is_console;
if (hvkbd_is_console)
hvkbd_is_console = 0;

if (sc->sc_console_keyboard) {
wskbd_cnattach(&hvkbd_consops, sc, &hvkbd_keymapdata);
hvkbd_enable(sc, 1);
}

a.console = sc->sc_console_keyboard;
a.keymap = &hvkbd_keymapdata;
a.accessops = &hvkbd_accessops;
a.accesscookie = sc;
sc->sc_wskbddev = config_found(self, &a, wskbddevprint, CFARGS_NONE);
return;

free_buf:
if (sc->sc_buf != NULL) {
kmem_free(sc->sc_buf, HVKBD_BUFSIZE);
sc->sc_buf = NULL;
}
hvkbd_free_keybuf(sc);
}

static int
hvkbd_alloc_keybuf(struct hvkbd_softc *sc)
{
struct hvkbd_keystroke_info *ksi;
int i;

for (i = 0; i < HVKBD_KEYBUF_SIZE; i++) {
ksi = kmem_zalloc(sizeof(*ksi), KM_SLEEP);
LIST_INSERT_HEAD(&sc->sc_ks_free, ksi, link);
}

return 0;
}

static void
hvkbd_free_keybuf(struct hvkbd_softc *sc)
{
struct hvkbd_keystroke_info *ksi;

while ((ksi = STAILQ_FIRST(&sc->sc_ks_queue)) != NULL) {
STAILQ_REMOVE(&sc->sc_ks_queue, ksi, hvkbd_keystroke_info,
slink);
kmem_free(ksi, sizeof(*ksi));
}
while ((ksi = LIST_FIRST(&sc->sc_ks_free)) != NULL) {
LIST_REMOVE(ksi, link);
kmem_free(ksi, sizeof(*ksi));
}
}

int
hvkbd_enable(void *v, int on)
{
struct hvkbd_softc *sc = v;

sc->sc_enabled = on;

return 0;
}

static void
hvkbd_set_leds(void *v, int leds)
{
}

static int
hvkbd_ioctl(void *v, u_long cmd, void *data, int flag, struct lwp *l)
{
#if defined(WSDISPLAY_COMPAT_RAWKBD)
struct hvkbd_softc *sc = v;
#endif

switch (cmd) {
case WSKBDIO_GTYPE:
*(int *)data = WSKBD_TYPE_HYPERV;
return 0;

case WSKBDIO_SETLEDS:
hvkbd_set_leds(v, *(int *)data);
return 0;

case WSKBDIO_GETLEDS:
*(int *)data = 0;
return 0;

#if defined(WSDISPLAY_COMPAT_RAWKBD)
case WSKBDIO_SETMODE:
sc->sc_rawkbd = (*(int *)data == WSKBD_RAW);
return 0;
#endif
}

return EPASSTHROUGH;
}

static int
hvkbd_connect(struct hvkbd_softc *sc)
{
struct hvkbd_proto_req req;
int timo = 100;
int error, s;

sc->sc_connected = 0;

memset(&req, 0, sizeof(req));
req.hdr.type = HVKBD_PROTO_REQUEST;
req.ver = HVKBD_VERSION;
error = vmbus_channel_send(sc->sc_chan, &req, sizeof(req),
0, VMBUS_CHANPKT_TYPE_INBAND, VMBUS_CHANPKT_FLAG_RC);
if (error) {
aprint_error_dev(sc->sc_dev, "failed to send connect: %d\n",
error);
return error;
}

do {
if (cold) {
delay(1000);
s = spltty();
hvkbd_intr(sc);
splx(s);
} else
tsleep(sc, PRIBIO | PCATCH, "hvkbdcon",
uimax(1, mstohz(1)));
} while (--timo > 0 && sc->sc_connected == 0);

if (timo == 0 && sc->sc_connected == 0) {
aprint_error_dev(sc->sc_dev, "connect timed out\n");
return ETIMEDOUT;
}

if (!(sc->sc_connect_status & RESP_STATUS_ACCEPTED)) {
aprint_error_dev(sc->sc_dev, "protocol request failed\n");
return ENODEV;
}

return 0;
}

static int
hvkbd_keybuf_add_keystroke(struct hvkbd_softc *sc, const struct keystroke *ks)
{
struct hvkbd_keystroke_info *ksi;

mutex_enter(&sc->sc_ks_lock);
ksi = LIST_FIRST(&sc->sc_ks_free);
if (ksi != NULL) {
LIST_REMOVE(ksi, link);
ksi->ks = *ks;
STAILQ_INSERT_TAIL(&sc->sc_ks_queue, ksi, slink);
}
mutex_exit(&sc->sc_ks_lock);

return (ksi != NULL) ? 0 : 1;
}

static int
hvkbd_decode(struct hvkbd_softc *sc, u_int *type, int *scancode)
{
struct hvkbd_keystroke_info *ksi;
struct keystroke ks;

mutex_enter(&sc->sc_ks_lock);
ksi = STAILQ_FIRST(&sc->sc_ks_queue);
if (ksi != NULL) {
STAILQ_REMOVE_HEAD(&sc->sc_ks_queue, slink);
ks = ksi->ks;
LIST_INSERT_HEAD(&sc->sc_ks_free, ksi, link);
}
mutex_exit(&sc->sc_ks_lock);

if (ksi == NULL)
return 0;

/*
* XXX: Hyper-V host send unicode to VM through 'Type clipboard text',
* the mapping from unicode to scancode depends on the keymap.
* It is so complicated that we do not plan to support it yet.
*/
if (ks.info & KS_INFO_UNICODE)
return 0;

*type = (ks.info & KS_INFO_BREAK) ?
WSCONS_EVENT_KEY_UP : WSCONS_EVENT_KEY_DOWN;
*scancode = ks.makecode;
return 1;
}

#if defined(WSDISPLAY_COMPAT_RAWKBD)
static int
hvkbd_encode(struct hvkbd_softc *sc, u_char *buf, int *len)
{
struct hvkbd_keystroke_info *ksi;
struct keystroke ks;
int i;

mutex_enter(&sc->sc_ks_lock);
ksi = STAILQ_FIRST(&sc->sc_ks_queue);
if (ksi != NULL) {
STAILQ_REMOVE_HEAD(&sc->sc_ks_queue, slink);
ks = ksi->ks;
LIST_INSERT_HEAD(&sc->sc_ks_free, ksi, link);
}
mutex_exit(&sc->sc_ks_lock);

if (ksi == NULL)
return 0;

/*
* XXX: Hyper-V host send unicode to VM through 'Type clipboard text',
* the mapping from unicode to scancode depends on the keymap.
* It is so complicated that we do not plan to support it yet.
*/
if (ks.info & KS_INFO_UNICODE)
return 0;

i = 0;
if (ks.info & (KS_INFO_E0|KS_INFO_E1)) {
if (ks.info & KS_INFO_E0)
buf[i++] = 0xe0;
else
buf[i++] = 0xe1;
}
if (ks.info & KS_INFO_BREAK)
buf[i++] = (u_char)ks.makecode & 0x80;
else
buf[i++] = (u_char)ks.makecode;

KDASSERT(i <= *len);
*len = i;

return 1;
}
#endif

static void
hvkbd_intr(void *xsc)
{
struct hvkbd_softc *sc = xsc;
struct vmbus_chanpkt_hdr *cph;
const struct hvkbd_msg_hdr *hdr;
const struct hvkbd_proto_resp *rsp;
const struct hvkbd_keystroke *ks;
uint64_t rid;
uint32_t rlen;
u_int type;
int key, error;

for (;;) {
error = vmbus_channel_recv(sc->sc_chan, sc->sc_buf,
HVKBD_BUFSIZE, &rlen, &rid, 1);
if (error != 0 || rlen == 0) {
if (error != EAGAIN)
device_printf(sc->sc_dev,
"failed to receive a reply packet\n");
return;
}

cph = (struct vmbus_chanpkt_hdr *)sc->sc_buf;
switch (cph->cph_type) {
case VMBUS_CHANPKT_TYPE_INBAND:
hdr = VMBUS_CHANPKT_CONST_DATA(cph);
if (rlen < sizeof(*hdr)) {
device_printf(sc->sc_dev, "Illegal packet\n");
continue;
}

switch (hdr->type) {
case HVKBD_PROTO_RESPONSE:
if (!sc->sc_connected) {
rsp = VMBUS_CHANPKT_CONST_DATA(cph);
if (rlen < sizeof(*rsp)) {
device_printf(sc->sc_dev,
"Illegal resp packet\n");
break;
}
sc->sc_connect_status = rsp->status;
sc->sc_connected = 1;
wakeup(sc);
}
break;

case HVKBD_PROTO_EVENT:
if (sc->sc_wskbddev == NULL || !sc->sc_enabled)
break;

ks = VMBUS_CHANPKT_CONST_DATA(cph);
hvkbd_keybuf_add_keystroke(sc, &ks->ks);
if (sc->sc_polling)
break;

#if defined(WSDISPLAY_COMPAT_RAWKBD)
if (sc->sc_rawkbd) {
u_char buf[2];
int len;

len = sizeof(buf);
if (hvkbd_encode(sc, buf, &len)) {
wskbd_rawinput(sc->sc_wskbddev,
buf, len);
}
break;
}
#endif
if (hvkbd_decode(sc, &type, &key))
wskbd_input(sc->sc_wskbddev, type, key);
break;

case HVKBD_PROTO_REQUEST:
case HVKBD_PROTO_LED_INDICATORS:
device_printf(sc->sc_dev,
"unhandled message: %d\n", hdr->type);
break;

default:
device_printf(sc->sc_dev,
"unknown message: %d\n", hdr->type);
break;
}
break;

case VMBUS_CHANPKT_TYPE_COMP:
case VMBUS_CHANPKT_TYPE_RXBUF:
device_printf(sc->sc_dev, "unhandled event: %d\n",
cph->cph_type);
break;

default:
device_printf(sc->sc_dev, "unknown event: %d\n",
cph->cph_type);
break;
}
}
}

int
hvkbd_cnattach(void)
{

hvkbd_is_console = 1;

return 0;
}

static void
hvkbd_cngetc(void *v, u_int *type, int *data)
{
struct hvkbd_softc *sc = v;

while (!hvkbd_decode(sc, type, data))
hvkbd_intr(sc);
}

static void
hvkbd_cnpollc(void *v, int on)
{
struct hvkbd_softc *sc = v;

sc->sc_polling = on;
}

MODULE(MODULE_CLASS_DRIVER, hvkbd, "vmbus");

#ifdef _MODULE
#include "ioconf.c"
#endif

static int
hvkbd_modcmd(modcmd_t cmd, void *aux)
{
int error = 0;

switch (cmd) {
case MODULE_CMD_INIT:
#ifdef _MODULE
error = config_init_component(cfdriver_ioconf_hvkbd,
cfattach_ioconf_hvkbd, cfdata_ioconf_hvkbd);
#endif
break;

case MODULE_CMD_FINI:
#ifdef _MODULE
error = config_fini_component(cfdriver_ioconf_hvtkbd,
cfattach_ioconf_hvkbd, cfdata_ioconf_hvkbd);
#endif
break;

case MODULE_CMD_AUTOUNLOAD:
error = EBUSY;
break;

default:
error = ENOTTY;
break;
}

return error;
}