[PATCH V2 03/12] misc: xilinx_sdfec: Add CCF support

[Dragan Cvetic <dragan.cvetic@xilinx.com>]

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: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c | 154 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 154 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 278754b..a52a5c6 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -37,6 +37,28 @@ static atomic_t xsdfec_ndevs = ATOMIC_INIT(0);
 static dev_t xsdfec_devt;
 
 /**
+ * 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
@@ -44,6 +66,7 @@ static dev_t xsdfec_devt;
  * @open_count: Count of char device being opened
  * @xsdfec_cdev: Character device handle
  * @irq_lock: Driver spinlock
+ * @clks: Clocks managed by the SDFEC driver
  *
  * This structure contains necessary state for SDFEC driver to operate
  */
@@ -55,12 +78,136 @@ struct xsdfec_dev {
 	struct cdev xsdfec_cdev;
 	/* Spinlock to protect state_updated and stats_updated */
 	spinlock_t irq_lock;
+	struct xsdfec_clks clks;
 };
 
 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))
+		clks->din_words_clk = NULL;
+
+	clks->din_clk = devm_clk_get(&pdev->dev, "s_axis_din_aclk");
+	if (IS_ERR(clks->din_clk))
+		clks->din_clk = NULL;
+
+	clks->dout_clk = devm_clk_get(&pdev->dev, "m_axis_dout_aclk");
+	if (IS_ERR(clks->dout_clk))
+		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))
+		clks->dout_words_clk = NULL;
+
+	clks->ctrl_clk = devm_clk_get(&pdev->dev, "s_axis_ctrl_aclk");
+	if (IS_ERR(clks->ctrl_clk))
+		clks->ctrl_clk = NULL;
+
+	clks->status_clk = devm_clk_get(&pdev->dev, "m_axis_status_aclk");
+	if (IS_ERR(clks->status_clk))
+		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 int xsdfec_probe(struct platform_device *pdev)
 {
 	struct xsdfec_dev *xsdfec;
@@ -77,6 +224,10 @@ static int xsdfec_probe(struct platform_device *pdev)
 	xsdfec->config.fec_id = atomic_read(&xsdfec_ndevs);
 	spin_lock_init(&xsdfec->irq_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);
@@ -124,6 +275,7 @@ static int xsdfec_probe(struct platform_device *pdev)
 err_xsdfec_cdev:
 	cdev_del(&xsdfec->xsdfec_cdev);
 err_xsdfec_dev:
+	xsdfec_disable_all_clks(&xsdfec->clks);
 	return err;
 }
 
@@ -141,6 +293,8 @@ static int xsdfec_remove(struct platform_device *pdev)
 		return -EIO;
 	}
 
+	xsdfec_disable_all_clks(&xsdfec->clks);
+
 	device_destroy(xsdfec_class,
 		       MKDEV(MAJOR(xsdfec_devt), xsdfec->config.fec_id));
 	cdev_del(&xsdfec->xsdfec_cdev);
-- 
2.7.4