[PATCH v5 07/20] iommu/mediatek: Add bclk can be supported optionally

[Yong Wu]

In some SoCs, M4U doesn't have its "bclk", it will use the EMI
clock instead which has always been enabled when entering kernel.

This also is a preparing patch for mt8183.

Signed-off-by: Yong Wu <yong...@mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 10 +++++++---
 drivers/iommu/mtk_iommu.h |  3 +++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index ae1aa5a..847082c 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -613,9 +613,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
        if (data->irq < 0)
                return data->irq;
 
-       data->bclk = devm_clk_get(dev, "bclk");
-       if (IS_ERR(data->bclk))
-               return PTR_ERR(data->bclk);
+       if (data->plat_data->has_bclk) {
+               data->bclk = devm_clk_get(dev, "bclk");
+               if (IS_ERR(data->bclk))
+                       return PTR_ERR(data->bclk);
+       }
 
        larb_nr = of_count_phandle_with_args(dev->of_node,
                                             "mediatek,larbs", NULL);
@@ -739,11 +741,13 @@ static int __maybe_unused mtk_iommu_resume(struct device 
*dev)
 static const struct mtk_iommu_plat_data mt2712_data = {
        .m4u_plat     = M4U_MT2712,
        .has_4gb_mode = true,
+       .has_bclk     = true,
 };
 
 static const struct mtk_iommu_plat_data mt8173_data = {
        .m4u_plat     = M4U_MT8173,
        .has_4gb_mode = true,
+       .has_bclk     = true,
 };
 
 static const struct of_device_id mtk_iommu_of_ids[] = {
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 5890e55..b8749ac 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -44,6 +44,9 @@ enum mtk_iommu_plat {
 struct mtk_iommu_plat_data {
        enum mtk_iommu_plat m4u_plat;
        bool                has_4gb_mode;
+
+       /* HW will use the EMI clock if there isn't the "bclk". */
+       bool                has_bclk;
 };
 
 struct mtk_iommu_domain;
-- 
1.9.1