Re: [PATCH 6/9] dev-serial: add always-plugged property to ensure USB device is always attached
On 27/10/2020 08:09, Gerd Hoffmann wrote:
case CHR_EVENT_OPENED:
-if (!s->dev.attached) {
+if (!s->always_plugged && !s->dev.attached) {
usb_device_attach(>dev, _abort);
}
Not needed (but doesn't hurt either).
Okay I'll leave this as-is for now.
break;
case CHR_EVENT_CLOSED:
-if (s->dev.attached) {
+if (!s->always_plugged && s->dev.attached) {
usb_device_detach(>dev);
}
Ok.
-if (qemu_chr_fe_backend_open(>cs) && !dev->attached) {
+if (s->always_plugged || (qemu_chr_fe_backend_open(>cs) &&
+ !dev->attached)) {
The dev->attached check should not be skipped, i.e. the logic should be
((always_plugged || open) && !attached).
Let me test this, and if it works I'll post a v2 shortly.
ATB,
Mark.
Re: [PATCH 6/9] dev-serial: add always-plugged property to ensure USB device is always attached
> case CHR_EVENT_OPENED:
> -if (!s->dev.attached) {
> +if (!s->always_plugged && !s->dev.attached) {
> usb_device_attach(>dev, _abort);
> }
Not needed (but doesn't hurt either).
> break;
> case CHR_EVENT_CLOSED:
> -if (s->dev.attached) {
> +if (!s->always_plugged && s->dev.attached) {
> usb_device_detach(>dev);
> }
Ok.
> -if (qemu_chr_fe_backend_open(>cs) && !dev->attached) {
> +if (s->always_plugged || (qemu_chr_fe_backend_open(>cs) &&
> + !dev->attached)) {
The dev->attached check should not be skipped, i.e. the logic should be
((always_plugged || open) && !attached).
take care,
Gerd
Re: [PATCH 6/9] dev-serial: add always-plugged property to ensure USB device is always attached
Mark Cave-Ayland, le lun. 26 oct. 2020 08:33:58 +, a ecrit:
> Some operating systems will generate a new device ID when a USB device is
> unplugged
> and then replugged into the USB. If this is done whilst switching between
> multiple
> applications over a virtual serial port, the change of device ID requires
> going
> back into the OS/application to locate the new device accordingly.
>
> Add a new always-plugged property that if specified will ensure that the
> device
> always remains attached to the USB regardless of the state of the backend
> chardev.
>
> Signed-off-by: Mark Cave-Ayland
Reviewed-by: Samuel Thibault
> ---
> hw/usb/dev-serial.c | 9 ++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/hw/usb/dev-serial.c b/hw/usb/dev-serial.c
> index 92c35615eb..919e25e1d9 100644
> --- a/hw/usb/dev-serial.c
> +++ b/hw/usb/dev-serial.c
> @@ -97,6 +97,7 @@ struct USBSerialState {
> uint8_t event_chr;
> uint8_t error_chr;
> uint8_t event_trigger;
> +bool always_plugged;
> QEMUSerialSetParams params;
> int latency;/* ms */
> CharBackend cs;
> @@ -516,12 +517,12 @@ static void usb_serial_event(void *opaque, QEMUChrEvent
> event)
> s->event_trigger |= FTDI_BI;
> break;
> case CHR_EVENT_OPENED:
> -if (!s->dev.attached) {
> +if (!s->always_plugged && !s->dev.attached) {
> usb_device_attach(>dev, _abort);
> }
> break;
> case CHR_EVENT_CLOSED:
> -if (s->dev.attached) {
> +if (!s->always_plugged && s->dev.attached) {
> usb_device_detach(>dev);
> }
> break;
> @@ -556,7 +557,8 @@ 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(>cs) && !dev->attached) {
> +if (s->always_plugged || (qemu_chr_fe_backend_open(>cs) &&
> + !dev->attached)) {
> usb_device_attach(dev, _abort);
> }
> s->intr = usb_ep_get(dev, USB_TOKEN_IN, 1);
> @@ -584,6 +586,7 @@ 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(),
> };
>
> --
> 2.20.1
>
--
Samuel
"...[Linux's] capacity to talk via any medium except smoke signals."
(By Dr. Greg Wettstein, Roger Maris Cancer Center)
[PATCH 6/9] dev-serial: add always-plugged property to ensure USB device is always attached
Some operating systems will generate a new device ID when a USB device is
unplugged
and then replugged into the USB. If this is done whilst switching between
multiple
applications over a virtual serial port, the change of device ID requires going
back into the OS/application to locate the new device accordingly.
Add a new always-plugged property that if specified will ensure that the device
always remains attached to the USB regardless of the state of the backend
chardev.
Signed-off-by: Mark Cave-Ayland
---
hw/usb/dev-serial.c | 9 ++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/hw/usb/dev-serial.c b/hw/usb/dev-serial.c
index 92c35615eb..919e25e1d9 100644
--- a/hw/usb/dev-serial.c
+++ b/hw/usb/dev-serial.c
@@ -97,6 +97,7 @@ struct USBSerialState {
uint8_t event_chr;
uint8_t error_chr;
uint8_t event_trigger;
+bool always_plugged;
QEMUSerialSetParams params;
int latency;/* ms */
CharBackend cs;
@@ -516,12 +517,12 @@ static void usb_serial_event(void *opaque, QEMUChrEvent
event)
s->event_trigger |= FTDI_BI;
break;
case CHR_EVENT_OPENED:
-if (!s->dev.attached) {
+if (!s->always_plugged && !s->dev.attached) {
usb_device_attach(>dev, _abort);
}
break;
case CHR_EVENT_CLOSED:
-if (s->dev.attached) {
+if (!s->always_plugged && s->dev.attached) {
usb_device_detach(>dev);
}
break;
@@ -556,7 +557,8 @@ 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(>cs) && !dev->attached) {
+if (s->always_plugged || (qemu_chr_fe_backend_open(>cs) &&
+ !dev->attached)) {
usb_device_attach(dev, _abort);
}
s->intr = usb_ep_get(dev, USB_TOKEN_IN, 1);
@@ -584,6 +586,7 @@ 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(),
};
--
2.20.1
