Re: [Qemu-trivial] [PATCH for 2.10 v2 20/20] i2c/exynos4210: fix write to I2CADD register, bit 0 is not mapped

[Michael Tokarev]

27.07.2017 05:42, Philippe Mathieu-Daudé wrote:
> From the Exynos4210 User Manual [1]:
> 
> 14.4.1.3 I2CADDn (MULTI-MASTER I2C-Bus Address Register)
>   [7-1] slave address, latched from the I2C-bus.
>   bit [0] is not mapped.
> 
> [1]: Exynos_4_Dual_45nm_User_Manaul_Public_REV1.00-0.pdf

Okay, so what happens when one writes to bit0?

> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
> ---
>  hw/i2c/exynos4210_i2c.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/i2c/exynos4210_i2c.c b/hw/i2c/exynos4210_i2c.c
> index c96fa7d7be..e6a9ca8f03 100644
> --- a/hw/i2c/exynos4210_i2c.c
> +++ b/hw/i2c/exynos4210_i2c.c
> @@ -243,7 +243,7 @@ static void exynos4210_i2c_write(void *opaque, hwaddr 
> offset,
>          break;
>      case I2CADD_ADDR:
>          if ((s->i2cstat & I2CSTAT_OUTPUT_EN) == 0) {
> -            s->i2cadd = v;
> +            s->i2cadd = v & ~1;

Maybe a comment is a good idea here, saying that bit0 is unmapped.

Thanks,

/mjt