From 7d748ffdee0dc244df3def1b2ec108bf095c0f9e Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Thu, 16 Jun 2022 13:08:27 +0200 Subject: iommu/mediatek: Lookup phandle to retrieve syscon to infracfg This driver will get support for more SoCs and the list of infracfg compatibles is expected to grow: in order to prevent getting this situation out of control and see a long list of compatible strings, add support to retrieve a handle to infracfg's regmap through a new "mediatek,infracfg" phandle. In order to keep retrocompatibility with older devicetrees, the old way is kept in place. Signed-off-by: AngeloGioacchino Del Regno Reviewed-by: Miles Chen Reviewed-by: Yong Wu Reviewed-by: Matthias Brugger Link: https://lore.kernel.org/r/20220616110830.26037-3-angelogioacchino.delregno@collabora.com Signed-off-by: Joerg Roedel --- drivers/iommu/mtk_iommu.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) (limited to 'drivers/iommu/mtk_iommu.c') diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index bb9dd92c9898..90685946fcbe 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -1140,22 +1140,32 @@ static int mtk_iommu_probe(struct platform_device *pdev) data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN); if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) { - switch (data->plat_data->m4u_plat) { - case M4U_MT2712: - p = "mediatek,mt2712-infracfg"; - break; - case M4U_MT8173: - p = "mediatek,mt8173-infracfg"; - break; - default: - p = NULL; + infracfg = syscon_regmap_lookup_by_phandle(dev->of_node, "mediatek,infracfg"); + if (IS_ERR(infracfg)) { + /* + * Legacy devicetrees will not specify a phandle to + * mediatek,infracfg: in that case, we use the older + * way to retrieve a syscon to infra. + * + * This is for retrocompatibility purposes only, hence + * no more compatibles shall be added to this. + */ + switch (data->plat_data->m4u_plat) { + case M4U_MT2712: + p = "mediatek,mt2712-infracfg"; + break; + case M4U_MT8173: + p = "mediatek,mt8173-infracfg"; + break; + default: + p = NULL; + } + + infracfg = syscon_regmap_lookup_by_compatible(p); + if (IS_ERR(infracfg)) + return PTR_ERR(infracfg); } - infracfg = syscon_regmap_lookup_by_compatible(p); - - if (IS_ERR(infracfg)) - return PTR_ERR(infracfg); - ret = regmap_read(infracfg, REG_INFRA_MISC, &val); if (ret) return ret; -- cgit v1.2.3