[PATCH RESEND v5 02/25] drm/msm/dp: introduce max_streams for DP controller MST support

[Yongxing Mou <yongxing.mou@oss.qualcomm.com>]

From: Abhinav Kumar <quic_abhinavk@quicinc.com>

DP controllers across different SoCs vary in the number of concurrent
MST streams they can support. Rather than hardcoding per-platform
values, the number of available pixel clocks in DT serves as a natural
indicator since each stream requires a dedicated pixel clock.

Introduce max_stream to capture this at initialization time and expose
it for the MST module to use during setup.

Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_ctrl.c    | 13 +++++++++++++
 drivers/gpu/drm/msm/dp/dp_ctrl.h    |  1 +
 drivers/gpu/drm/msm/dp/dp_display.c | 12 ++++++++++++
 drivers/gpu/drm/msm/dp/dp_display.h |  1 +
 4 files changed, 27 insertions(+)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index a475e787656e..68fb4facb056 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -127,6 +127,7 @@ struct msm_dp_ctrl_private {
 	struct clk_bulk_data *link_clks;
 
 	struct clk *pixel_clk[DP_STREAM_MAX];
+	unsigned int num_pixel_clks;
 
 	union phy_configure_opts phy_opts;
 
@@ -2754,6 +2755,7 @@ static int msm_dp_ctrl_clk_init(struct msm_dp_ctrl *msm_dp_ctrl)
 	if (rc)
 		return rc;
 
+	ctrl->num_pixel_clks = 0;
 	for (i = DP_STREAM_0; i < DP_STREAM_MAX; i++) {
 		ctrl->pixel_clk[i] = devm_clk_get(dev, pixel_clks[i]);
 
@@ -2766,11 +2768,22 @@ static int msm_dp_ctrl_clk_init(struct msm_dp_ctrl *msm_dp_ctrl)
 			DRM_DEBUG_DP("stream %d pixel clock not found", i);
 			break;
 		}
+
+		ctrl->num_pixel_clks++;
 	}
 
 	return 0;
 }
 
+int msm_dp_ctrl_get_stream_cnt(struct msm_dp_ctrl *msm_dp_ctrl)
+{
+	struct msm_dp_ctrl_private *ctrl;
+
+	ctrl = container_of(msm_dp_ctrl, struct msm_dp_ctrl_private, msm_dp_ctrl);
+
+	return ctrl->num_pixel_clks;
+}
+
 struct msm_dp_ctrl *msm_dp_ctrl_get(struct device *dev, struct msm_dp_link *link,
 			struct drm_dp_aux *aux,
 			struct phy *phy,
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp_ctrl.h
index be0d89d60914..305add3dcd93 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
@@ -55,4 +55,5 @@ void msm_dp_ctrl_enable_irq(struct msm_dp_ctrl *msm_dp_ctrl);
 void msm_dp_ctrl_disable_irq(struct msm_dp_ctrl *msm_dp_ctrl);
 
 void msm_dp_ctrl_reinit_phy(struct msm_dp_ctrl *msm_dp_ctrl);
+int msm_dp_ctrl_get_stream_cnt(struct msm_dp_ctrl *dp_ctrl);
 #endif /* _DP_CTRL_H_ */
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index bb243ab09e66..9cd243411e44 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -87,6 +87,8 @@ struct msm_dp_display_private {
 
 	void __iomem *p0_base;
 	size_t p0_len;
+
+	int max_stream;
 };
 
 struct msm_dp_desc {
@@ -578,6 +580,7 @@ static int msm_dp_init_sub_modules(struct msm_dp_display_private *dp)
 		dp->ctrl = NULL;
 		goto error_link;
 	}
+	dp->max_stream = msm_dp_ctrl_get_stream_cnt(dp->ctrl);
 
 	dp->audio = msm_dp_audio_get(dp->msm_dp_display.pdev, dp->link_base);
 	if (IS_ERR(dp->audio)) {
@@ -1178,6 +1181,15 @@ static int msm_dp_display_get_io(struct msm_dp_display_private *display)
 	return 0;
 }
 
+int msm_dp_get_mst_max_stream(struct msm_dp *msm_dp_display)
+{
+	struct msm_dp_display_private *dp;
+
+	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
+
+	return dp->max_stream;
+}
+
 static int msm_dp_display_probe(struct platform_device *pdev)
 {
 	int rc = 0;
diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h
index 43ed79093e24..d3d4ab98089d 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.h
+++ b/drivers/gpu/drm/msm/dp/dp_display.h
@@ -26,6 +26,7 @@ struct msm_dp {
 	bool psr_supported;
 };
 
+int msm_dp_get_mst_max_stream(struct msm_dp *msm_dp_display);
 int msm_dp_display_get_modes(struct msm_dp *msm_dp_display);
 bool msm_dp_display_check_video_test(struct msm_dp *msm_dp_display);
 int msm_dp_display_get_test_bpp(struct msm_dp *msm_dp_display);

-- 
2.43.0