Re: [PATCH v10 14/21] drm/mediatek: dpi: Add dpintf support

dpintf is the displayport interface hardware unit. This unit is similar
to dpi and can reuse most of the code.

This patch adds support for mt8195-dpintf to this dpi driver. Main
differences are:
  - Some features/functional components are not available for dpintf
    which are now excluded from code execution once is_dpintf is set
  - dpintf can and needs to choose between different clockdividers based
    on the clockspeed. This is done by choosing a different clock parent.
  - There are two additional clocks that need to be managed. These are
    only set for dpintf and will be set to NULL if not supplied. The
    clk_* calls handle these as normal clocks then.
  - Some register contents differ slightly between the two components. To
    work around this I added register bits/masks with a DPINTF_ prefix
    and use them where different.

Based on a separate driver for dpintf created by
Jason-JH.Lin [off-list ref].

Signed-off-by: Markus Schneider-Pargmann <msp-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>
Signed-off-by: Guillaume Ranquet <granquet-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>
---
  drivers/gpu/drm/mediatek/mtk_dpi.c          | 126 +++++++++++++++++---
  drivers/gpu/drm/mediatek/mtk_dpi_regs.h     |  35 ++++++
  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   8 ++
  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |   1 +
  drivers/gpu/drm/mediatek/mtk_drm_drv.c      |   5 +-
  include/linux/soc/mediatek/mtk-mmsys.h      |   4 +-
  6 files changed, 159 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index eb969c5c5c2e..763bfb700135 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c

@@ -71,6 +71,7 @@ struct mtk_dpi {
  	void __iomem *regs;
  	struct device *dev;
  	struct clk *engine_clk;
+	struct clk *dpi_ck_cg;
  	struct clk *pixel_clk;
  	struct clk *tvd_clk;
  	int irq;

@@ -126,6 +127,7 @@ struct mtk_dpi_conf {
  	const u32 *output_fmts;
  	u32 num_output_fmts;
  	bool is_ck_de_pol;
+	bool is_dpintf;
  	bool swap_input_support;
  	/* Mask used for HWIDTH, HPORCH, VSYNC_WIDTH and VSYNC_PORCH (no shift) */
  	u32 dimension_mask;

@@ -438,6 +440,8 @@ static void mtk_dpi_power_off(struct mtk_dpi *dpi)
  	mtk_dpi_disable(dpi);
  	clk_disable_unprepare(dpi->pixel_clk);
  	clk_disable_unprepare(dpi->engine_clk);
+	clk_disable_unprepare(dpi->dpi_ck_cg);
+	clk_disable_unprepare(dpi->tvd_clk);
  }
  
  static int mtk_dpi_power_on(struct mtk_dpi *dpi)

@@ -447,12 +451,24 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi)
  	if (++dpi->refcount != 1)
  		return 0;
  

+	ret = clk_prepare_enable(dpi->tvd_clk);
+	if (ret) {
+		dev_err(dpi->dev, "Failed to enable tvd pll: %d\n", ret);
+		goto err_pixel;
+	}
+
  	ret = clk_prepare_enable(dpi->engine_clk);
  	if (ret) {
  		dev_err(dpi->dev, "Failed to enable engine clock: %d\n", ret);
  		goto err_refcount;
  	}
  
+	ret = clk_prepare_enable(dpi->dpi_ck_cg);
+	if (ret) {
+		dev_err(dpi->dev, "Failed to enable dpi_ck_cg clock: %d\n", ret);
+		goto err_ck_cg;
+	}
+
  	ret = clk_prepare_enable(dpi->pixel_clk);
  	if (ret) {
  		dev_err(dpi->dev, "Failed to enable pixel clock: %d\n", ret);

@@ -466,6 +482,8 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi)
  	return 0;
  
  err_pixel:
+	clk_disable_unprepare(dpi->dpi_ck_cg);
+err_ck_cg:
  	clk_disable_unprepare(dpi->engine_clk);
  err_refcount:
  	dpi->refcount--;