firmware: qcom_scm: Always try to consume all three clocks

The code for handling more than 1 clock is a bit messy and requires
one to add new, SoC-specific compatibles if one wants to attach a clock.

Switch devm_clk_get to devm_clk_get_optional to prevent throwing it
from throwing errors when the clock is absent and defer checking the
clock requirements to dt schema.

This lets us get rid of compatibles that aren't necessary for backwards
compatibility *and* will hopefully prevent the addition of meaningless
new compatibles.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230623-topic-scm_cleanup-v2-1-9db8c583138d@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Author: konradybcio

drivers/firmware/qcom_scm.c

@@ -26,10 +26,6 @@
 static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
 module_param(download_mode, bool, 0);
 
-#define SCM_HAS_CORE_CLK	BIT(0)
-#define SCM_HAS_IFACE_CLK	BIT(1)
-#define SCM_HAS_BUS_CLK		BIT(2)
-
 struct qcom_scm {
 	struct device *dev;
 	struct clk *core_clk;
@@ -1405,7 +1401,6 @@ static irqreturn_t qcom_scm_irq_handler(int irq, void *data)
 static int qcom_scm_probe(struct platform_device *pdev)
 {
 	struct qcom_scm *scm;
-	unsigned long clks;
 	int irq, ret;
 
 	scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
@@ -1418,50 +1413,27 @@ static int qcom_scm_probe(struct platform_device *pdev)
 
 	mutex_init(&scm->scm_bw_lock);
 
-	clks = (unsigned long)of_device_get_match_data(&pdev->dev);
-
 	scm->path = devm_of_icc_get(&pdev->dev, NULL);
 	if (IS_ERR(scm->path))
 		return dev_err_probe(&pdev->dev, PTR_ERR(scm->path),
 				     "failed to acquire interconnect path\n");
 
-	scm->core_clk = devm_clk_get(&pdev->dev, "core");
+	scm->core_clk = devm_clk_get_optional(&pdev->dev, "core");
 	if (IS_ERR(scm->core_clk)) {
 		if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
 			return PTR_ERR(scm->core_clk);
-
-		if (clks & SCM_HAS_CORE_CLK) {
-			dev_err(&pdev->dev, "failed to acquire core clk\n");
-			return PTR_ERR(scm->core_clk);
-		}
-
-		scm->core_clk = NULL;
 	}
 
-	scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
+	scm->iface_clk = devm_clk_get_optional(&pdev->dev, "iface");
 	if (IS_ERR(scm->iface_clk)) {
 		if (PTR_ERR(scm->iface_clk) == -EPROBE_DEFER)
 			return PTR_ERR(scm->iface_clk);
-
-		if (clks & SCM_HAS_IFACE_CLK) {
-			dev_err(&pdev->dev, "failed to acquire iface clk\n");
-			return PTR_ERR(scm->iface_clk);
-		}
-
-		scm->iface_clk = NULL;
 	}
 
-	scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
+	scm->bus_clk = devm_clk_get_optional(&pdev->dev, "bus");
 	if (IS_ERR(scm->bus_clk)) {
 		if (PTR_ERR(scm->bus_clk) == -EPROBE_DEFER)
 			return PTR_ERR(scm->bus_clk);
-
-		if (clks & SCM_HAS_BUS_CLK) {
-			dev_err(&pdev->dev, "failed to acquire bus clk\n");
-			return PTR_ERR(scm->bus_clk);
-		}
-
-		scm->bus_clk = NULL;
 	}
 
 	scm->reset.ops = &qcom_scm_pas_reset_ops;
@@ -1512,38 +1484,19 @@ static void qcom_scm_shutdown(struct platform_device *pdev)
 }
 
 static const struct of_device_id qcom_scm_dt_match[] = {
-	{ .compatible = "qcom,scm-apq8064",
-	  /* FIXME: This should have .data = (void *) SCM_HAS_CORE_CLK */
-	},
-	{ .compatible = "qcom,scm-apq8084", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK)
-	},
+	{ .compatible = "qcom,scm-apq8064" },
+	{ .compatible = "qcom,scm-apq8084" },
 	{ .compatible = "qcom,scm-ipq4019" },
-	{ .compatible = "qcom,scm-mdm9607", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK) },
-	{ .compatible = "qcom,scm-msm8660", .data = (void *) SCM_HAS_CORE_CLK },
-	{ .compatible = "qcom,scm-msm8960", .data = (void *) SCM_HAS_CORE_CLK },
-	{ .compatible = "qcom,scm-msm8916", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK)
-	},
-	{ .compatible = "qcom,scm-msm8953", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK)
-	},
-	{ .compatible = "qcom,scm-msm8974", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK)
-	},
-	{ .compatible = "qcom,scm-msm8976", .data = (void *)(SCM_HAS_CORE_CLK |
-							     SCM_HAS_IFACE_CLK |
-							     SCM_HAS_BUS_CLK)
-	},
+	{ .compatible = "qcom,scm-mdm9607" },
+	{ .compatible = "qcom,scm-msm8660" },
+	{ .compatible = "qcom,scm-msm8960" },
+	{ .compatible = "qcom,scm-msm8916" },
+	{ .compatible = "qcom,scm-msm8953" },
+	{ .compatible = "qcom,scm-msm8974" },
+	{ .compatible = "qcom,scm-msm8976" },
 	{ .compatible = "qcom,scm-msm8994" },
 	{ .compatible = "qcom,scm-msm8996" },
-	{ .compatible = "qcom,scm-sm6375", .data = (void *)SCM_HAS_CORE_CLK },
+	{ .compatible = "qcom,scm-sm6375" },
 	{ .compatible = "qcom,scm" },
 	{}
 };