Re: [PATCH v7 4/8] iio: dac: adi-axi-dac: extend features

["Nuno Sá" <noname.nuno@gmail.com>]

On Mon, 2024-10-21 at 14:40 +0200, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Extend AXI-DAC backend with new features required to interface
> to the ad3552r DAC. Mainly, a new compatible string is added to
> support the ad3552r-axi DAC IP, very similar to the generic DAC
> IP but with some customizations to work with the ad3552r.
> 
> Then, a series of generic functions has been added to match with
> ad3552r needs. Function names has been kept generic as much as
> possible, to allow re-utilization from other frontend drivers.
> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---

Looks mostly good,

one minor thing that (I think) could be improved
>  drivers/iio/dac/adi-axi-dac.c | 269 +++++++++++++++++++++++++++++++++++++++--
> -
>  1 file changed, 255 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> index 04193a98616e..9d6809fe7a67 100644
> --- a/drivers/iio/dac/adi-axi-dac.c
> +++ b/drivers/iio/dac/adi-axi-dac.c
> @@ -46,9 +46,28 @@
>  #define AXI_DAC_CNTRL_1_REG			0x0044
>  #define   AXI_DAC_CNTRL_1_SYNC			BIT(0)
>  #define AXI_DAC_CNTRL_2_REG			0x0048
> +#define   AXI_DAC_CNTRL_2_SDR_DDR_N		BIT(16)
> +#define   AXI_DAC_CNTRL_2_SYMB_8B		BIT(14)
>  #define   ADI_DAC_CNTRL_2_R1_MODE		BIT(5)
> +#define   AXI_DAC_CNTRL_2_UNSIGNED_DATA		BIT(4)
> +#define AXI_DAC_STATUS_1_REG			0x0054
> +#define AXI_DAC_STATUS_2_REG			0x0058
>  #define AXI_DAC_DRP_STATUS_REG			0x0074
>  #define   AXI_DAC_DRP_STATUS_DRP_LOCKED		BIT(17)
> +#define AXI_DAC_CUSTOM_RD_REG			0x0080
> +#define AXI_DAC_CUSTOM_WR_REG			0x0084
> +#define   AXI_DAC_CUSTOM_WR_DATA_8		GENMASK(23, 16)
> +#define   AXI_DAC_CUSTOM_WR_DATA_16		GENMASK(23, 8)
> +#define AXI_DAC_UI_STATUS_REG			0x0088
> +#define   AXI_DAC_UI_STATUS_IF_BUSY		BIT(4)
> +#define AXI_DAC_CUSTOM_CTRL_REG			0x008C
> +#define   AXI_DAC_CUSTOM_CTRL_ADDRESS		GENMASK(31, 24)
> +#define   AXI_DAC_CUSTOM_CTRL_SYNCED_TRANSFER	BIT(2)
> +#define   AXI_DAC_CUSTOM_CTRL_STREAM		BIT(1)
> +#define   AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA	BIT(0)

...
 
>  static int axi_dac_probe(struct platform_device *pdev)
>  {
> -	const unsigned int *expected_ver;
>  	struct axi_dac_state *st;
>  	void __iomem *base;
>  	unsigned int ver;
> @@ -566,14 +780,29 @@ static int axi_dac_probe(struct platform_device *pdev)
>  	if (!st)
>  		return -ENOMEM;
>  
> -	expected_ver = device_get_match_data(&pdev->dev);
> -	if (!expected_ver)
> +	st->info = device_get_match_data(&pdev->dev);
> +	if (!st->info)
>  		return -ENODEV;
> +	clk = devm_clk_get_enabled(&pdev->dev, "s_axi_aclk");
> +	if (IS_ERR(clk)) {

If clock-names is not given, then we'll get -EINVAL. Hence we could assume that:

		if (PTR_ERR(clk) != -EINVAL)
			return dev_err_probe();

- Nuno Sá