Re: [PATCHv5 4/6] mmc: dw_mmc-pltfm: socfpga: add method to configure clk-phase

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 19/10/2022 13:06, Dinh Nguyen wrote:
> The clock-phase settings for the SDMMC controller in the SoCFPGA
> platforms reside in a register in the System Manager. Add a method
> to access that register through the syscon interface.
> 
> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
> ---
> v5: change error handling from of_property_read_variable_u32_array()
>     support arm32 by reading the reg_shift
> v4: no change
> v3: add space before &socfpga_drv_data
> v2: simplify clk-phase calculations
> ---
>  drivers/mmc/host/dw_mmc-pltfm.c | 43 ++++++++++++++++++++++++++++++++-
>  1 file changed, 42 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c
> index 9901208be797..74421d13f466 100644
> --- a/drivers/mmc/host/dw_mmc-pltfm.c
> +++ b/drivers/mmc/host/dw_mmc-pltfm.c
> @@ -17,10 +17,16 @@
>  #include <linux/mmc/host.h>
>  #include <linux/mmc/mmc.h>
>  #include <linux/of.h>
> +#include <linux/mfd/altera-sysmgr.h>
> +#include <linux/regmap.h>
>  
>  #include "dw_mmc.h"
>  #include "dw_mmc-pltfm.h"
>  
> +#define SOCFPGA_DW_MMC_CLK_PHASE_STEP	45
> +#define SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel, reg_shift) \
> +	((((smplsel) & 0x7) << reg_shift) | (((drvsel) & 0x7) << 0))
> +
>  int dw_mci_pltfm_register(struct platform_device *pdev,
>  			  const struct dw_mci_drv_data *drv_data)
>  {
> @@ -62,9 +68,44 @@ const struct dev_pm_ops dw_mci_pltfm_pmops = {
>  };
>  EXPORT_SYMBOL_GPL(dw_mci_pltfm_pmops);
>  
> +static int dw_mci_socfpga_priv_init(struct dw_mci *host)
> +{
> +	struct device_node *np = host->dev->of_node;
> +	struct regmap *sys_mgr_base_addr;
> +	u32 clk_phase[2] = {0}, reg_offset, reg_shift;
> +	int i, rc, hs_timing;
> +
> +	rc = of_property_read_variable_u32_array(np, "clk-phase-sd-hs", &clk_phase[0], 2, 0);
> +	if (rc < 0) {
> +		dev_err(host->dev, "clk-phase-sd-hs not found!\n");
> +		return rc;
> +	}
> +
> +	sys_mgr_base_addr = altr_sysmgr_regmap_lookup_by_phandle(np, "altr,sysmgr-syscon");
> +	if (IS_ERR(sys_mgr_base_addr)) {
> +		dev_err(host->dev, "failed to find altr,sys-mgr regmap!\n");
> +		return -ENODEV;

Isn't this now an ABI break? I have an impression we talked about this...

Best regards,
Krzysztof