misc: xilinx_sdfec: Add CCF support

Add the support for Linux Clock Control Framework (CCF).
Registers and enables clocks with the Clock Control
Framework (CCF), to prevent shared clocks from been
disabled.
Tested-by: NDragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: NDerek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: NDragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/xilinx_sdfec.c

@@ -25,12 +25,35 @@
 static struct idr dev_idr;
 static struct mutex dev_idr_lock;
 
+/**
+ * struct xsdfec_clks - For managing SD-FEC clocks
+ * @core_clk: Main processing clock for core
+ * @axi_clk: AXI4-Lite memory-mapped clock
+ * @din_words_clk: DIN Words AXI4-Stream Slave clock
+ * @din_clk: DIN AXI4-Stream Slave clock
+ * @dout_clk: DOUT Words AXI4-Stream Slave clock
+ * @dout_words_clk: DOUT AXI4-Stream Slave clock
+ * @ctrl_clk: Control AXI4-Stream Slave clock
+ * @status_clk: Status AXI4-Stream Slave clock
+ */
+struct xsdfec_clks {
+	struct clk *core_clk;
+	struct clk *axi_clk;
+	struct clk *din_words_clk;
+	struct clk *din_clk;
+	struct clk *dout_clk;
+	struct clk *dout_words_clk;
+	struct clk *ctrl_clk;
+	struct clk *status_clk;
+};
+
 /**
  * struct xsdfec_dev - Driver data for SDFEC
  * @regs: device physical base address
  * @dev: pointer to device struct
  * @miscdev: Misc device handle
  * @error_data_lock: Error counter and states spinlock
+ * @clks: Clocks managed by the SDFEC driver
  * @dev_name: Device name
  * @dev_id: Device ID
  *
@@ -42,6 +65,7 @@ struct xsdfec_dev {
 	struct miscdevice miscdev;
 	/* Spinlock to protect state_updated and stats_updated */
 	spinlock_t error_data_lock;
+	struct xsdfec_clks clks;
 	char dev_name[DEV_NAME_LEN];
 	int dev_id;
 };
@@ -50,6 +74,159 @@ static const struct file_operations xsdfec_fops = {
 	.owner = THIS_MODULE,
 };
 
+static int xsdfec_clk_init(struct platform_device *pdev,
+			   struct xsdfec_clks *clks)
+{
+	int err;
+
+	clks->core_clk = devm_clk_get(&pdev->dev, "core_clk");
+	if (IS_ERR(clks->core_clk)) {
+		dev_err(&pdev->dev, "failed to get core_clk");
+		return PTR_ERR(clks->core_clk);
+	}
+
+	clks->axi_clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
+	if (IS_ERR(clks->axi_clk)) {
+		dev_err(&pdev->dev, "failed to get axi_clk");
+		return PTR_ERR(clks->axi_clk);
+	}
+
+	clks->din_words_clk = devm_clk_get(&pdev->dev, "s_axis_din_words_aclk");
+	if (IS_ERR(clks->din_words_clk)) {
+		if (PTR_ERR(clks->din_words_clk) != -ENOENT) {
+			err = PTR_ERR(clks->din_words_clk);
+			return err;
+		}
+		clks->din_words_clk = NULL;
+	}
+
+	clks->din_clk = devm_clk_get(&pdev->dev, "s_axis_din_aclk");
+	if (IS_ERR(clks->din_clk)) {
+		if (PTR_ERR(clks->din_clk) != -ENOENT) {
+			err = PTR_ERR(clks->din_clk);
+			return err;
+		}
+		clks->din_clk = NULL;
+	}
+
+	clks->dout_clk = devm_clk_get(&pdev->dev, "m_axis_dout_aclk");
+	if (IS_ERR(clks->dout_clk)) {
+		if (PTR_ERR(clks->dout_clk) != -ENOENT) {
+			err = PTR_ERR(clks->dout_clk);
+			return err;
+		}
+		clks->dout_clk = NULL;
+	}
+
+	clks->dout_words_clk =
+		devm_clk_get(&pdev->dev, "s_axis_dout_words_aclk");
+	if (IS_ERR(clks->dout_words_clk)) {
+		if (PTR_ERR(clks->dout_words_clk) != -ENOENT) {
+			err = PTR_ERR(clks->dout_words_clk);
+			return err;
+		}
+		clks->dout_words_clk = NULL;
+	}
+
+	clks->ctrl_clk = devm_clk_get(&pdev->dev, "s_axis_ctrl_aclk");
+	if (IS_ERR(clks->ctrl_clk)) {
+		if (PTR_ERR(clks->ctrl_clk) != -ENOENT) {
+			err = PTR_ERR(clks->ctrl_clk);
+			return err;
+		}
+		clks->ctrl_clk = NULL;
+	}
+
+	clks->status_clk = devm_clk_get(&pdev->dev, "m_axis_status_aclk");
+	if (IS_ERR(clks->status_clk)) {
+		if (PTR_ERR(clks->status_clk) != -ENOENT) {
+			err = PTR_ERR(clks->status_clk);
+			return err;
+		}
+		clks->status_clk = NULL;
+	}
+
+	err = clk_prepare_enable(clks->core_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable core_clk (%d)", err);
+		return err;
+	}
+
+	err = clk_prepare_enable(clks->axi_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable axi_clk (%d)", err);
+		goto err_disable_core_clk;
+	}
+
+	err = clk_prepare_enable(clks->din_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable din_clk (%d)", err);
+		goto err_disable_axi_clk;
+	}
+
+	err = clk_prepare_enable(clks->din_words_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable din_words_clk (%d)", err);
+		goto err_disable_din_clk;
+	}
+
+	err = clk_prepare_enable(clks->dout_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable dout_clk (%d)", err);
+		goto err_disable_din_words_clk;
+	}
+
+	err = clk_prepare_enable(clks->dout_words_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable dout_words_clk (%d)",
+			err);
+		goto err_disable_dout_clk;
+	}
+
+	err = clk_prepare_enable(clks->ctrl_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable ctrl_clk (%d)", err);
+		goto err_disable_dout_words_clk;
+	}
+
+	err = clk_prepare_enable(clks->status_clk);
+	if (err) {
+		dev_err(&pdev->dev, "failed to enable status_clk (%d)\n", err);
+		goto err_disable_ctrl_clk;
+	}
+
+	return err;
+
+err_disable_ctrl_clk:
+	clk_disable_unprepare(clks->ctrl_clk);
+err_disable_dout_words_clk:
+	clk_disable_unprepare(clks->dout_words_clk);
+err_disable_dout_clk:
+	clk_disable_unprepare(clks->dout_clk);
+err_disable_din_words_clk:
+	clk_disable_unprepare(clks->din_words_clk);
+err_disable_din_clk:
+	clk_disable_unprepare(clks->din_clk);
+err_disable_axi_clk:
+	clk_disable_unprepare(clks->axi_clk);
+err_disable_core_clk:
+	clk_disable_unprepare(clks->core_clk);
+
+	return err;
+}
+
+static void xsdfec_disable_all_clks(struct xsdfec_clks *clks)
+{
+	clk_disable_unprepare(clks->status_clk);
+	clk_disable_unprepare(clks->ctrl_clk);
+	clk_disable_unprepare(clks->dout_words_clk);
+	clk_disable_unprepare(clks->dout_clk);
+	clk_disable_unprepare(clks->din_words_clk);
+	clk_disable_unprepare(clks->din_clk);
+	clk_disable_unprepare(clks->core_clk);
+	clk_disable_unprepare(clks->axi_clk);
+}
+
 static void xsdfec_idr_remove(struct xsdfec_dev *xsdfec)
 {
 	mutex_lock(&dev_idr_lock);
@@ -71,12 +248,16 @@ static int xsdfec_probe(struct platform_device *pdev)
 	xsdfec->dev = &pdev->dev;
 	spin_lock_init(&xsdfec->error_data_lock);
 
+	err = xsdfec_clk_init(pdev, &xsdfec->clks);
+	if (err)
+		return err;
+
 	dev = xsdfec->dev;
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	xsdfec->regs = devm_ioremap_resource(dev, res);
 	if (IS_ERR(xsdfec->regs)) {
 		err = PTR_ERR(xsdfec->regs);
-		return err;
+		goto err_xsdfec_dev;
 	}
 
 	/* Save driver private data */
@@ -86,7 +267,7 @@ static int xsdfec_probe(struct platform_device *pdev)
 	err = idr_alloc(&dev_idr, xsdfec->dev_name, 0, 0, GFP_KERNEL);
 	mutex_unlock(&dev_idr_lock);
 	if (err < 0)
-		goto err_xsddev_idr;
+		goto err_xsdfec_dev;
 	xsdfec->dev_id = err;
 
 	snprintf(xsdfec->dev_name, DEV_NAME_LEN, "xsdfec%d", xsdfec->dev_id);
@@ -97,13 +278,14 @@ static int xsdfec_probe(struct platform_device *pdev)
 	err = misc_register(&xsdfec->miscdev);
 	if (err) {
 		dev_err(dev, "error:%d. Unable to register device", err);
-		return err;
+		goto err_xsdfec_idr;
 	}
 	return 0;
 
-err_xsddev_idr:
+err_xsdfec_idr:
 	xsdfec_idr_remove(xsdfec);
-
+err_xsdfec_dev:
+	xsdfec_disable_all_clks(&xsdfec->clks);
 	return err;
 }
 
@@ -114,6 +296,7 @@ static int xsdfec_remove(struct platform_device *pdev)
 	xsdfec = platform_get_drvdata(pdev);
 	misc_deregister(&xsdfec->miscdev);
 	xsdfec_idr_remove(xsdfec);
+	xsdfec_disable_all_clks(&xsdfec->clks);
 	return 0;
 }