[PATCH v2 2/3] drm/msm/dpu: Attach INT2 power domain alongside MMCX on Kaanapali

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

Kaanapali's DPU node lists two power domains when its DT provides
both MMCX and INT2 GDSC. The power-domain core only auto-attaches a
single power domain; with two phandles it leaves the device
unattached to either, so attach both explicitly.

MMCX keeps PD_FLAG_REQUIRED_OPP, preserving its existing OPP-based
performance-state voting. INT2 has no OPP of its own and is attached
as a plain runtime-PM supplier, via the device link the attach API
creates automatically, so it needs no manual pm_runtime get/put in
the enable/disable paths.

Platforms with a single power domain are unaffected and continue to
rely on the core's existing single-domain auto-attach.

Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index da3556eb6ecc..d9c2c8d680fd 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -12,6 +12,7 @@
 #include <linux/debugfs.h>
 #include <linux/dma-buf.h>
 #include <linux/of_irq.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_opp.h>
 
 #include <drm/drm_crtc.h>
@@ -1376,6 +1377,33 @@ static int dpu_kms_mmap_dpu(struct dpu_kms *dpu_kms)
 	return 0;
 }
 
+static int dpu_kms_attach_power_domains(struct device *dev)
+{
+	static const char * const mmcx_names[] = { "mmcx" };
+	static const char * const int2_names[] = { "int2" };
+	const struct dev_pm_domain_attach_data mmcx_pd = {
+		.pd_names = mmcx_names,
+		.num_pd_names = ARRAY_SIZE(mmcx_names),
+		.pd_flags = PD_FLAG_REQUIRED_OPP,
+	};
+	const struct dev_pm_domain_attach_data int2_pd = {
+		.pd_names = int2_names,
+		.num_pd_names = ARRAY_SIZE(int2_names),
+	};
+	struct dev_pm_domain_list *mmcx_list, *int2_list;
+	int ret;
+
+	if (of_count_phandle_with_args(dev->of_node, "power-domains",
+				       "#power-domain-cells") <= 1)
+		return 0;
+
+	ret = devm_pm_domain_attach_list(dev, &mmcx_pd, &mmcx_list);
+	if (ret < 0)
+		return ret;
+
+	return devm_pm_domain_attach_list(dev, &int2_pd, &int2_list);
+}
+
 static int dpu_dev_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -1392,6 +1420,10 @@ static int dpu_dev_probe(struct platform_device *pdev)
 
 	dpu_kms->pdev = pdev;
 
+	ret = dpu_kms_attach_power_domains(dev);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to attach power domains\n");
+
 	ret = devm_pm_opp_set_clkname(dev, "core");
 	if (ret)
 		return ret;

-- 
2.43.0