Re: [PATCH 9/9] dev-serial: store flow control and xon/xoff characters

[Samuel Thibault <samuel.thibault@gnu.org>]

Mark Cave-Ayland, le lun. 26 oct. 2020 08:34:01 +0000, a ecrit:
> Note that whilst the device does not do anything with these values, they are
> logged with trace events and stored to allow future implementation.
> 
> The default flow control is set to none at reset as documented in the Linux
> ftdi_sio.h header file.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

> ---
>  hw/usb/dev-serial.c | 38 +++++++++++++++++++++++++++++++++++---
>  hw/usb/trace-events |  2 ++
>  2 files changed, 37 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/usb/dev-serial.c b/hw/usb/dev-serial.c
> index fa734bcf54..3dbc56d77a 100644
> --- a/hw/usb/dev-serial.c
> +++ b/hw/usb/dev-serial.c
> @@ -52,6 +52,7 @@
>  
>  /* SET_FLOW_CTRL */
>  
> +#define FTDI_NO_HS         0
>  #define FTDI_RTS_CTS_HS    1
>  #define FTDI_DTR_DSR_HS    2
>  #define FTDI_XON_XOFF_HS   4
> @@ -98,6 +99,9 @@ struct USBSerialState {
>      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;
> @@ -181,14 +185,36 @@ 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)
> @@ -285,9 +311,15 @@ static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
>          qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_TIOCM, &flags);
>          break;
>      }
> -    case VendorDeviceOutRequest | 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 VendorDeviceOutRequest | FTDI_SET_BAUD: {
>          static const int subdivisors8[8] = { 0, 4, 2, 1, 3, 5, 6, 7 };
>          int subdivisor8 = subdivisors8[((value & 0xc000) >> 14)
> diff --git a/hw/usb/trace-events b/hw/usb/trace-events
> index 0d0a3e5f2a..725b7077ad 100644
> --- a/hw/usb/trace-events
> +++ b/hw/usb/trace-events
> @@ -331,3 +331,5 @@ usb_serial_unsupported_data_bits(int bus, int addr, int value) "dev %d:%d unsupp
>  usb_serial_bad_token(int bus, int addr) "dev %d:%d bad token"
>  usb_serial_set_baud(int bus, int addr, int baud) "dev %d:%d baud rate %d"
>  usb_serial_set_data(int bus, int addr, int parity, int data, int stop) "dev %d:%d parity %c, data bits %d, stop bits %d"
> +usb_serial_set_flow_control(int bus, int addr, int index) "dev %d:%d flow control %d"
> +usb_serial_set_xonxoff(int bus, int addr, uint8_t xon, uint8_t xoff) "dev %d:%d xon 0x%x xoff 0x%x"
> -- 
> 2.20.1
> 

-- 
Samuel
> 	dvips -o $@ $<     
Faut faire gffe de pas te couper avec ton truc, t'as mis des ciseaux ($<)
partout :))
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