Re: [Qemu-devel] [PATCH] hw/i2c: QOM'ify i2c slave

[Peter Maydell]

On 14 January 2018 at 02:45, Philippe Mathieu-Daudé <address@hidden> wrote:
> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
> ---
>  hw/i2c/core.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/hw/i2c/core.c b/hw/i2c/core.c
> index 59068f157e..c84dbfb884 100644
> --- a/hw/i2c/core.c
> +++ b/hw/i2c/core.c
> @@ -8,6 +8,7 @@
>   */
>
>  #include "qemu/osdep.h"
> +#include "qapi/error.h"
>  #include "hw/i2c/i2c.h"
>
>  typedef struct I2CNode I2CNode;
> @@ -276,16 +277,15 @@ const VMStateDescription vmstate_i2c_slave = {
>      }
>  };
>
> -static int i2c_slave_qdev_init(DeviceState *dev)
> +static void i2c_slave_realize(DeviceState *dev, Error **errp)
>  {
>      I2CSlave *s = I2C_SLAVE(dev);
>      I2CSlaveClass *sc = I2C_SLAVE_GET_CLASS(s);
>
> -    if (sc->init) {
> -        return sc->init(s);
> +    if (sc->init && sc->init(s)) {
> +        error_setg(errp, "i2c slave initialization failed");
> +        return;
>      }
> -
> -    return 0;
>  }
>
>  DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr)
> @@ -301,7 +301,7 @@ DeviceState *i2c_create_slave(I2CBus *bus, const char 
> *name, uint8_t addr)
>  static void i2c_slave_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *k = DEVICE_CLASS(klass);
> -    k->init = i2c_slave_qdev_init;
> +    k->realize = i2c_slave_realize;
>      set_bit(DEVICE_CATEGORY_MISC, k->categories);
>      k->bus_type = TYPE_I2C_BUS;
>      k->props = i2c_props;

This is changing the semantics of the I2CSlaveClass::init
method. Is that really OK? (If nothing else, it means
that we end up with a method named init which is called
at realize time, which is confusing, and which doesn't
have an API like realize which allows it to fill in
an Error**.)

thanks
-- PMM