Re: [PATCH] ssi: Display chip select polarity in monitor 'info qtree'

[Alistair Francis <alistair23@gmail.com>]

On Sun, Sep 27, 2020 at 2:20 AM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> It is sometime useful to verify a device chip select polarity
> on a SPI bus. Since we have this information available, display
> it in the 'info qtree' monitor output:
>
>   $ qemu-system-arm -M lm3s6965evb -monitor stdio -S
>   (qemu) info qtree
>   [...]
>   dev: pl022, id ""
>     gpio-out "sysbus-irq" 1
>     mmio 0000000040008000/0000000000001000
>     bus: ssi
>       type SSI
>       dev: ssd0323, id ""
>         gpio-in "" 1
>         gpio-in "ssi-gpio-cs" 1
>         chip select polarity: high           <---
>       dev: ssi-sd, id ""
>         gpio-in "ssi-gpio-cs" 1
>         chip select polarity: low            <---
>         bus: sd-bus
>           type sd-bus
>           dev: sd-card, id ""
>             spec_version = 2 (0x2)
>             drive = "sd0"
>             spi = true
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/ssi/ssi.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>
> diff --git a/hw/ssi/ssi.c b/hw/ssi/ssi.c
> index 4278d0e4440..4c9f8d66d23 100644
> --- a/hw/ssi/ssi.c
> +++ b/hw/ssi/ssi.c
> @@ -17,6 +17,7 @@
>  #include "migration/vmstate.h"
>  #include "qemu/module.h"
>  #include "qapi/error.h"
> +#include "monitor/monitor.h"
>  #include "qom/object.h"
>
>  struct SSIBus {
> @@ -26,10 +27,31 @@ struct SSIBus {
>  #define TYPE_SSI_BUS "SSI"
>  OBJECT_DECLARE_SIMPLE_TYPE(SSIBus, SSI_BUS)
>
> +static void ssi_print_dev(Monitor *mon, DeviceState *dev, int indent)
> +{
> +    static const char *const polarity_s[] = {
> +        [SSI_CS_NONE] = "unknown",
> +        [SSI_CS_LOW]  = "low",
> +        [SSI_CS_HIGH] = "high"
> +    };
> +    SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev);
> +
> +    monitor_printf(mon, "%*schip select polarity: %s\n",
> +                   indent, "", polarity_s[ssc->cs_polarity]);
> +}
> +
> +static void ssi_bus_class_init(ObjectClass *klass, void *data)
> +{
> +    BusClass *k = BUS_CLASS(klass);
> +
> +    k->print_dev = ssi_print_dev;
> +}
> +
>  static const TypeInfo ssi_bus_info = {
>      .name = TYPE_SSI_BUS,
>      .parent = TYPE_BUS,
>      .instance_size = sizeof(SSIBus),
> +    .class_init = ssi_bus_class_init,
>  };
>
>  static void ssi_cs_default(void *opaque, int n, int level)
> --
> 2.26.2
>
>