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usb: bugfixes for usb-serial

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Merge remote-tracking branch 'remotes/kraxel/tags/usb-20201104-pull-request' into staging

usb: bugfixes for usb-serial

# gpg: Signature made Wed 04 Nov 2020 12:13:05 GMT
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/usb-20201104-pull-request:
  dev-serial: store flow control and xon/xoff characters
  dev-serial: add support for setting data_bits in QEMUSerialSetParams
  dev-serial: add always-plugged property to ensure USB device is always attached
  dev-serial: replace DeviceOutVendor/DeviceInVendor with equivalent macros from usb.h
  dev-serial: add trace-events for baud rate and data parameters
  dev-serial: convert from DPRINTF to trace-events
  dev-serial: use USB_SERIAL QOM macro for USBSerialState assignments
  dev-serial: style changes to improve readability and checkpatch fixes

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Peter Maydell 2020-11-04 14:13:07 +00:00
commit b1266b6ee5
2 changed files with 216 additions and 131 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

334
hw/usb/dev-serial.c
View File

@ -20,85 +20,77 @@
#include "chardev/char-serial.h"
#include "chardev/char-fe.h"
#include "qom/object.h"
#include "trace.h"
//#define DEBUG_Serial
#ifdef DEBUG_Serial
#define DPRINTF(fmt, ...) \
do { printf("usb-serial: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while(0)
#endif
#define RECV_BUF (512 - (2 * 8))
/* Commands */
#define FTDI_RESET 0
#define FTDI_SET_MDM_CTRL 1
#define FTDI_SET_FLOW_CTRL 2
#define FTDI_SET_BAUD 3
#define FTDI_SET_DATA 4
#define FTDI_GET_MDM_ST 5
#define FTDI_SET_EVENT_CHR 6
#define FTDI_SET_ERROR_CHR 7
#define FTDI_SET_LATENCY 9
#define FTDI_GET_LATENCY 10
#define DeviceOutVendor ((USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
#define DeviceInVendor ((USB_DIR_IN |USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
#define FTDI_RESET 0
#define FTDI_SET_MDM_CTRL 1
#define FTDI_SET_FLOW_CTRL 2
#define FTDI_SET_BAUD 3
#define FTDI_SET_DATA 4
#define FTDI_GET_MDM_ST 5
#define FTDI_SET_EVENT_CHR 6
#define FTDI_SET_ERROR_CHR 7
#define FTDI_SET_LATENCY 9
#define FTDI_GET_LATENCY 10
/* RESET */
#define FTDI_RESET_SIO 0
#define FTDI_RESET_RX 1
#define FTDI_RESET_TX 2
#define FTDI_RESET_SIO 0
#define FTDI_RESET_RX 1
#define FTDI_RESET_TX 2
/* SET_MDM_CTRL */
#define FTDI_DTR 1
#define FTDI_SET_DTR (FTDI_DTR << 8)
#define FTDI_RTS 2
#define FTDI_SET_RTS (FTDI_RTS << 8)
#define FTDI_DTR 1
#define FTDI_SET_DTR (FTDI_DTR << 8)
#define FTDI_RTS 2
#define FTDI_SET_RTS (FTDI_RTS << 8)
/* SET_FLOW_CTRL */
#define FTDI_RTS_CTS_HS 1
#define FTDI_DTR_DSR_HS 2
#define FTDI_XON_XOFF_HS 4
#define FTDI_NO_HS 0
#define FTDI_RTS_CTS_HS 1
#define FTDI_DTR_DSR_HS 2
#define FTDI_XON_XOFF_HS 4
/* SET_DATA */
#define FTDI_PARITY (0x7 << 8)
#define FTDI_ODD (0x1 << 8)
#define FTDI_EVEN (0x2 << 8)
#define FTDI_MARK (0x3 << 8)
#define FTDI_SPACE (0x4 << 8)
#define FTDI_PARITY (0x7 << 8)
#define FTDI_ODD (0x1 << 8)
#define FTDI_EVEN (0x2 << 8)
#define FTDI_MARK (0x3 << 8)
#define FTDI_SPACE (0x4 << 8)
#define FTDI_STOP (0x3 << 11)
#define FTDI_STOP1 (0x0 << 11)
#define FTDI_STOP15 (0x1 << 11)
#define FTDI_STOP2 (0x2 << 11)
#define FTDI_STOP (0x3 << 11)
#define FTDI_STOP1 (0x0 << 11)
#define FTDI_STOP15 (0x1 << 11)
#define FTDI_STOP2 (0x2 << 11)
/* GET_MDM_ST */
/* TODO: should be sent every 40ms */
#define FTDI_CTS (1<<4) // CTS line status
#define FTDI_DSR (1<<5) // DSR line status
#define FTDI_RI (1<<6) // RI line status
#define FTDI_RLSD (1<<7) // Receive Line Signal Detect
#define FTDI_CTS (1 << 4) /* CTS line status */
#define FTDI_DSR (1 << 5) /* DSR line status */
#define FTDI_RI (1 << 6) /* RI line status */
#define FTDI_RLSD (1 << 7) /* Receive Line Signal Detect */
/* Status */
#define FTDI_DR (1<<0) // Data Ready
#define FTDI_OE (1<<1) // Overrun Err
#define FTDI_PE (1<<2) // Parity Err
#define FTDI_FE (1<<3) // Framing Err
#define FTDI_BI (1<<4) // Break Interrupt
#define FTDI_THRE (1<<5) // Transmitter Holding Register
#define FTDI_TEMT (1<<6) // Transmitter Empty
#define FTDI_FIFO (1<<7) // Error in FIFO
#define FTDI_DR (1 << 0) /* Data Ready */
#define FTDI_OE (1 << 1) /* Overrun Err */
#define FTDI_PE (1 << 2) /* Parity Err */
#define FTDI_FE (1 << 3) /* Framing Err */
#define FTDI_BI (1 << 4) /* Break Interrupt */
#define FTDI_THRE (1 << 5) /* Transmitter Holding Register */
#define FTDI_TEMT (1 << 6) /* Transmitter Empty */
#define FTDI_FIFO (1 << 7) /* Error in FIFO */
struct USBSerialState {
USBDevice dev;
USBEndpoint *intr;
uint8_t recv_buf[RECV_BUF];
uint16_t recv_ptr;
@ -106,6 +98,10 @@ struct USBSerialState {
uint8_t event_chr;
uint8_t error_chr;
uint8_t event_trigger;
bool always_plugged;
uint8_t flow_control;
uint8_t xon;
uint8_t xoff;
QEMUSerialSetParams params;
int latency; /* ms */
CharBackend cs;
@ -189,21 +185,44 @@ static const USBDesc desc_braille = {
.str = desc_strings,
};
static void usb_serial_set_flow_control(USBSerialState *s,
uint8_t flow_control)
{
USBDevice *dev = USB_DEVICE(s);
USBBus *bus = usb_bus_from_device(dev);
/* TODO: ioctl */
s->flow_control = flow_control;
trace_usb_serial_set_flow_control(bus->busnr, dev->addr, flow_control);
}
static void usb_serial_set_xonxoff(USBSerialState *s, int xonxoff)
{
USBDevice *dev = USB_DEVICE(s);
USBBus *bus = usb_bus_from_device(dev);
s->xon = xonxoff & 0xff;
s->xoff = (xonxoff >> 8) & 0xff;
trace_usb_serial_set_xonxoff(bus->busnr, dev->addr, s->xon, s->xoff);
}
static void usb_serial_reset(USBSerialState *s)
{
/* TODO: Set flow control to none */
s->event_chr = 0x0d;
s->event_trigger = 0;
s->recv_ptr = 0;
s->recv_used = 0;
/* TODO: purge in char driver */
usb_serial_set_flow_control(s, FTDI_NO_HS);
}
static void usb_serial_handle_reset(USBDevice *dev)
{
USBSerialState *s = (USBSerialState *)dev;
USBSerialState *s = USB_SERIAL(dev);
USBBus *bus = usb_bus_from_device(dev);
DPRINTF("Reset\n");
trace_usb_serial_reset(bus->busnr, dev->addr);
usb_serial_reset(s);
/* TODO: Reset char device, send BREAK? */
@ -216,29 +235,36 @@ static uint8_t usb_get_modem_lines(USBSerialState *s)
if (qemu_chr_fe_ioctl(&s->cs,
CHR_IOCTL_SERIAL_GET_TIOCM, &flags) == -ENOTSUP) {
return FTDI_CTS|FTDI_DSR|FTDI_RLSD;
return FTDI_CTS | FTDI_DSR | FTDI_RLSD;
}
ret = 0;
if (flags & CHR_TIOCM_CTS)
if (flags & CHR_TIOCM_CTS) {
ret |= FTDI_CTS;
if (flags & CHR_TIOCM_DSR)
}
if (flags & CHR_TIOCM_DSR) {
ret |= FTDI_DSR;
if (flags & CHR_TIOCM_RI)
}
if (flags & CHR_TIOCM_RI) {
ret |= FTDI_RI;
if (flags & CHR_TIOCM_CAR)
}
if (flags & CHR_TIOCM_CAR) {
ret |= FTDI_RLSD;
}
return ret;
}
static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
int request, int value, int index, int length, uint8_t *data)
int request, int value, int index,
int length, uint8_t *data)
{
USBSerialState *s = (USBSerialState *)dev;
USBSerialState *s = USB_SERIAL(dev);
USBBus *bus = usb_bus_from_device(dev);
int ret;
DPRINTF("got control %x, value %x\n",request, value);
trace_usb_serial_handle_control(bus->busnr, dev->addr, request, value);
ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
if (ret >= 0) {
return;
@ -248,8 +274,8 @@ static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
break;
/* Class specific requests. */
case DeviceOutVendor | FTDI_RESET:
/* Class specific requests. */
case VendorDeviceOutRequest | FTDI_RESET:
switch (value) {
case FTDI_RESET_SIO:
usb_serial_reset(s);
@ -264,96 +290,131 @@ static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
break;
}
break;
case DeviceOutVendor | FTDI_SET_MDM_CTRL:
case VendorDeviceOutRequest | FTDI_SET_MDM_CTRL:
{
static int flags;
qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_GET_TIOCM, &flags);
if (value & FTDI_SET_RTS) {
if (value & FTDI_RTS)
if (value & FTDI_RTS) {
flags |= CHR_TIOCM_RTS;
else
} else {
flags &= ~CHR_TIOCM_RTS;
}
}
if (value & FTDI_SET_DTR) {
if (value & FTDI_DTR)
if (value & FTDI_DTR) {
flags |= CHR_TIOCM_DTR;
else
} else {
flags &= ~CHR_TIOCM_DTR;
}
}
qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_TIOCM, &flags);
break;
}
case DeviceOutVendor | FTDI_SET_FLOW_CTRL:
/* TODO: ioctl */
case VendorDeviceOutRequest | FTDI_SET_FLOW_CTRL: {
uint8_t flow_control = index >> 8;
usb_serial_set_flow_control(s, flow_control);
if (flow_control & FTDI_XON_XOFF_HS) {
usb_serial_set_xonxoff(s, value);
}
break;
case DeviceOutVendor | FTDI_SET_BAUD: {
}
case VendorDeviceOutRequest | FTDI_SET_BAUD: {
static const int subdivisors8[8] = { 0, 4, 2, 1, 3, 5, 6, 7 };
int subdivisor8 = subdivisors8[((value & 0xc000) >> 14)
| ((index & 1) << 2)];
int divisor = value & 0x3fff;
/* chip special cases */
if (divisor == 1 && subdivisor8 == 0)
if (divisor == 1 && subdivisor8 == 0) {
subdivisor8 = 4;
if (divisor == 0 && subdivisor8 == 0)
}
if (divisor == 0 && subdivisor8 == 0) {
divisor = 1;
}
s->params.speed = (48000000 / 2) / (8 * divisor + subdivisor8);
trace_usb_serial_set_baud(bus->busnr, dev->addr, s->params.speed);
qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
break;
}
case DeviceOutVendor | FTDI_SET_DATA:
case VendorDeviceOutRequest | FTDI_SET_DATA:
switch (value & 0xff) {
case 7:
s->params.data_bits = 7;
break;
case 8:
s->params.data_bits = 8;
break;
default:
/*
* According to a comment in Linux's ftdi_sio.c original FTDI
* chips fall back to 8 data bits for unsupported data_bits
*/
trace_usb_serial_unsupported_data_bits(bus->busnr, dev->addr,
value & 0xff);
s->params.data_bits = 8;
}
switch (value & FTDI_PARITY) {
case 0:
s->params.parity = 'N';
break;
case FTDI_ODD:
s->params.parity = 'O';
break;
case FTDI_EVEN:
s->params.parity = 'E';
break;
default:
DPRINTF("unsupported parity %d\n", value & FTDI_PARITY);
goto fail;
case 0:
s->params.parity = 'N';
break;
case FTDI_ODD:
s->params.parity = 'O';
break;
case FTDI_EVEN:
s->params.parity = 'E';
break;
default:
trace_usb_serial_unsupported_parity(bus->busnr, dev->addr,
value & FTDI_PARITY);
goto fail;
}
switch (value & FTDI_STOP) {
case FTDI_STOP1:
s->params.stop_bits = 1;
break;
case FTDI_STOP2:
s->params.stop_bits = 2;
break;
default:
DPRINTF("unsupported stop bits %d\n", value & FTDI_STOP);
goto fail;
case FTDI_STOP1:
s->params.stop_bits = 1;
break;
case FTDI_STOP2:
s->params.stop_bits = 2;
break;
default:
trace_usb_serial_unsupported_stopbits(bus->busnr, dev->addr,
value & FTDI_STOP);
goto fail;
}
trace_usb_serial_set_data(bus->busnr, dev->addr, s->params.parity,
s->params.data_bits, s->params.stop_bits);
qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
/* TODO: TX ON/OFF */
break;
case DeviceInVendor | FTDI_GET_MDM_ST:
case VendorDeviceRequest | FTDI_GET_MDM_ST:
data[0] = usb_get_modem_lines(s) | 1;
data[1] = FTDI_THRE | FTDI_TEMT;
p->actual_length = 2;
break;
case DeviceOutVendor | FTDI_SET_EVENT_CHR:
case VendorDeviceOutRequest | FTDI_SET_EVENT_CHR:
/* TODO: handle it */
s->event_chr = value;
break;
case DeviceOutVendor | FTDI_SET_ERROR_CHR:
case VendorDeviceOutRequest | FTDI_SET_ERROR_CHR:
/* TODO: handle it */
s->error_chr = value;
break;
case DeviceOutVendor | FTDI_SET_LATENCY:
case VendorDeviceOutRequest | FTDI_SET_LATENCY:
s->latency = value;
break;
case DeviceInVendor | FTDI_GET_LATENCY:
case VendorDeviceRequest | FTDI_GET_LATENCY:
data[0] = s->latency;
p->actual_length = 1;
break;
default:
fail:
DPRINTF("got unsupported/bogus control %x, value %x\n", request, value);
trace_usb_serial_unsupported_control(bus->busnr, dev->addr, request,
value);
p->status = USB_RET_STALL;
break;
}
@ -416,32 +477,37 @@ static void usb_serial_token_in(USBSerialState *s, USBPacket *p)
static void usb_serial_handle_data(USBDevice *dev, USBPacket *p)
{
USBSerialState *s = (USBSerialState *)dev;
USBSerialState *s = USB_SERIAL(dev);
USBBus *bus = usb_bus_from_device(dev);
uint8_t devep = p->ep->nr;
struct iovec *iov;
int i;
switch (p->pid) {
case USB_TOKEN_OUT:
if (devep != 2)
if (devep != 2) {
goto fail;
}
for (i = 0; i < p->iov.niov; i++) {
iov = p->iov.iov + i;
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
/*
* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks
*/
qemu_chr_fe_write_all(&s->cs, iov->iov_base, iov->iov_len);
}
p->actual_length = p->iov.size;
break;
case USB_TOKEN_IN:
if (devep != 1)
if (devep != 1) {
goto fail;
}
usb_serial_token_in(s, p);
break;
default:
DPRINTF("Bad token\n");
trace_usb_serial_bad_token(bus->busnr, dev->addr);
fail:
p->status = USB_RET_STALL;
break;
@ -464,21 +530,24 @@ static void usb_serial_read(void *opaque, const uint8_t *buf, int size)
int first_size, start;
/* room in the buffer? */
if (size > (RECV_BUF - s->recv_used))
if (size > (RECV_BUF - s->recv_used)) {
size = RECV_BUF - s->recv_used;
}
start = s->recv_ptr + s->recv_used;
if (start < RECV_BUF) {
/* copy data to end of buffer */
first_size = RECV_BUF - start;
if (first_size > size)
if (first_size > size) {
first_size = size;
}
memcpy(s->recv_buf + start, buf, first_size);
/* wrap around to front if needed */
if (size > first_size)
if (size > first_size) {
memcpy(s->recv_buf, buf + first_size, size - first_size);
}
} else {
start -= RECV_BUF;
memcpy(s->recv_buf + start, buf, size);
@ -493,23 +562,23 @@ static void usb_serial_event(void *opaque, QEMUChrEvent event)
USBSerialState *s = opaque;
switch (event) {
case CHR_EVENT_BREAK:
s->event_trigger |= FTDI_BI;
break;
case CHR_EVENT_OPENED:
if (!s->dev.attached) {
usb_device_attach(&s->dev, &error_abort);
}
break;
case CHR_EVENT_CLOSED:
if (s->dev.attached) {
usb_device_detach(&s->dev);
}
break;
case CHR_EVENT_MUX_IN:
case CHR_EVENT_MUX_OUT:
/* Ignore */
break;
case CHR_EVENT_BREAK:
s->event_trigger |= FTDI_BI;
break;
case CHR_EVENT_OPENED:
if (!s->always_plugged && !s->dev.attached) {
usb_device_attach(&s->dev, &error_abort);
}
break;
case CHR_EVENT_CLOSED:
if (!s->always_plugged && s->dev.attached) {
usb_device_detach(&s->dev);
}
break;
case CHR_EVENT_MUX_IN:
case CHR_EVENT_MUX_OUT:
/* Ignore */
break;
}
}
@ -537,7 +606,8 @@ static void usb_serial_realize(USBDevice *dev, Error **errp)
usb_serial_event, NULL, s, NULL, true);
usb_serial_handle_reset(dev);
if (qemu_chr_fe_backend_open(&s->cs) && !dev->attached) {
if ((s->always_plugged || qemu_chr_fe_backend_open(&s->cs)) &&
!dev->attached) {
usb_device_attach(dev, &error_abort);
}
s->intr = usb_ep_get(dev, USB_TOKEN_IN, 1);
@ -549,8 +619,9 @@ static USBDevice *usb_braille_init(const char *unused)
Chardev *cdrv;
cdrv = qemu_chr_new("braille", "braille", NULL);
if (!cdrv)
if (!cdrv) {
return NULL;
}
dev = usb_new("usb-braille");
qdev_prop_set_chr(&dev->qdev, "chardev", cdrv);
@ -564,6 +635,7 @@ static const VMStateDescription vmstate_usb_serial = {
static Property serial_properties[] = {
DEFINE_PROP_CHR("chardev", USBSerialState, cs),
DEFINE_PROP_BOOL("always-plugged", USBSerialState, always_plugged, false),
DEFINE_PROP_END_OF_LIST(),
};

13
hw/usb/trace-events
View File

@ -320,3 +320,16 @@ usb_host_parse_interface(int bus, int addr, int num, int alt, int active) "dev %
usb_host_parse_endpoint(int bus, int addr, int ep, const char *dir, const char *type, int active) "dev %d:%d, ep %d, %s, %s, active %d"
usb_host_parse_error(int bus, int addr, const char *errmsg) "dev %d:%d, msg %s"
usb_host_remote_wakeup_removed(int bus, int addr) "dev %d:%d"
# dev-serial.c
usb_serial_reset(int bus, int addr) "dev %d:%u reset"
usb_serial_handle_control(int bus, int addr, int request, int value) "dev %d:%u got control 0x%x, value 0x%x"
usb_serial_unsupported_parity(int bus, int addr, int value) "dev %d:%u unsupported parity %d"
usb_serial_unsupported_stopbits(int bus, int addr, int value) "dev %d:%u unsupported stop bits %d"
usb_serial_unsupported_control(int bus, int addr, int request, int value) "dev %d:%u got unsupported/bogus control 0x%x, value 0x%x"
usb_serial_unsupported_data_bits(int bus, int addr, int value) "dev %d:%u unsupported data bits %d, falling back to 8"
usb_serial_bad_token(int bus, int addr) "dev %d:%u bad token"
usb_serial_set_baud(int bus, int addr, int baud) "dev %d:%u baud rate %d"
usb_serial_set_data(int bus, int addr, int parity, int data, int stop) "dev %d:%u parity %c, data bits %d, stop bits %d"
usb_serial_set_flow_control(int bus, int addr, int index) "dev %d:%u flow control %d"
usb_serial_set_xonxoff(int bus, int addr, uint8_t xon, uint8_t xoff) "dev %d:%u xon 0x%x xoff 0x%x"