On Tue, 2016-12-06 at 14:57 +0700, Tin Huynh wrote:
> ACPI always sets txfifo and rxfifo to 32. This configuration will
> cause problem if the IP core supports a fifo size of less than 32.
> The driver should read the fifo size from the IP and select the 
> smaller one of the two.
> 
> Signed-off-by: Tin Huynh <tnhu...@apm.com>
> 

The idea looks good, but see my comment below.

> >dev);
> +     u32 param1, tx_fifo_depth, rx_fifo_depth;
>       struct dw_i2c_dev *dev;
>       struct i2c_adapter *adap;
>       struct resource *mem;
> @@ -246,12 +247,18 @@ static int dw_i2c_plat_probe(struct
> platform_device *pdev)
>                               1000000);
>       }
>  
> +     param1 = i2c_dw_read_comp_param(dev);
> +     tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
> +     rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
>       if (!dev->tx_fifo_depth) {
> -             u32 param1 = i2c_dw_read_comp_param(dev);
> -
> -             dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
> -             dev->rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
> +             dev->tx_fifo_depth = tx_fifo_depth;
> +             dev->rx_fifo_depth = rx_fifo_depth;
>               dev->adapter.nr = pdev->id;
> +     } else if (tx_fifo_depth) {
> +             dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
> +                                                     tx_fifo_depth
> );
> +             dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
> +                                                     rx_fifo_dept

Can we move this to a separate function like

static void dw_i2c_set_fifo_size(... *dev, ... id)
{
        u32 param, tx_fifo_depth, rx_fifo_depth;

        param = i2c_dw_read_comp_param(dev);
        tx_fifo_depth = ((param >> 16) & 0xff) + 1;
        rx_fifo_depth = ((param >> 8)  & 0xff) + 1;

        if (!dev->tx_fifo_depth) {
                dev->tx_fifo_depth = tx_fifo_depth;
                dev->rx_fifo_depth = rx_fifo_depth;
                dev->adapter.nr = id;
        }

        dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
tx_fifo_depth);
        dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
rx_fifo_depth);
}

?

-- 
Andy Shevchenko <andriy.shevche...@linux.intel.com>
Intel Finland Oy

Reply via email to