spi: zynqmp: Add pm runtime support

This patch adds runtime pm functions.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Naga Sureshkumar Relli <nagasure@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index 18aeaceee2862017f4cd4bb13a5e3c6bd36f6ea7..26d1ac3bf4965b48342ce632453e1f96d97609a0 100644 (file)
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -20,6 +20,7 @@
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/spi/spi.h>
 #include <linux/spinlock.h>
 #include <linux/workqueue.h>
@@ -135,6 +136,7 @@
 #define GQSPI_DMA_UNALIGN              0x3
 #define GQSPI_DEFAULT_NUM_CS   1       /* Default number of chip selects */
 
+#define SPI_AUTOSUSPEND_TIMEOUT                3000
 enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
 
 /**
@@ -356,21 +358,9 @@ static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
 static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
 {
        struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
-       int ret;
-
-       ret = clk_enable(xqspi->refclk);
-       if (ret)
-               return ret;
-
-       ret = clk_enable(xqspi->pclk);
-       if (ret)
-               goto clk_err;
 
        zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
        return 0;
-clk_err:
-       clk_disable(xqspi->refclk);
-       return ret;
 }
 
 /**
@@ -387,8 +377,6 @@ static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
        struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 
        zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
-       clk_disable(xqspi->refclk);
-       clk_disable(xqspi->pclk);
        return 0;
 }
 
@@ -959,11 +947,67 @@ static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
 
        spi_master_resume(master);
 
+       clk_disable(xqspi->refclk);
+       clk_disable(xqspi->pclk);
        return 0;
 }
 
-static SIMPLE_DEV_PM_OPS(zynqmp_qspi_dev_pm_ops, zynqmp_qspi_suspend,
-                        zynqmp_qspi_resume);
+/**
+ * zynqmp_runtime_suspend - Runtime suspend method for the SPI driver
+ * @dev:       Address of the platform_device structure
+ *
+ * This function disables the clocks
+ *
+ * Return:     Always 0
+ */
+static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct spi_master *master = platform_get_drvdata(pdev);
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+       clk_disable(xqspi->refclk);
+       clk_disable(xqspi->pclk);
+
+       return 0;
+}
+
+/**
+ * zynqmp_runtime_resume - Runtime resume method for the SPI driver
+ * @dev:       Address of the platform_device structure
+ *
+ * This function enables the clocks
+ *
+ * Return:     0 on success and error value on error
+ */
+static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct spi_master *master = platform_get_drvdata(pdev);
+       struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+       int ret;
+
+       ret = clk_enable(xqspi->pclk);
+       if (ret) {
+               dev_err(dev, "Cannot enable APB clock.\n");
+               return ret;
+       }
+
+       ret = clk_enable(xqspi->refclk);
+       if (ret) {
+               dev_err(dev, "Cannot enable device clock.\n");
+               clk_disable(xqspi->pclk);
+               return ret;
+       }
+
+       return 0;
+}
+
+static const struct dev_pm_ops zynqmp_qspi_dev_pm_ops = {
+       SET_RUNTIME_PM_OPS(zynqmp_runtime_suspend,
+                          zynqmp_runtime_resume, NULL)
+       SET_SYSTEM_SLEEP_PM_OPS(zynqmp_qspi_suspend, zynqmp_qspi_resume)
+};
 
 /**
  * zynqmp_qspi_probe:  Probe method for the QSPI driver
@@ -1023,9 +1067,15 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
                goto clk_dis_pclk;
        }
 
+       pm_runtime_use_autosuspend(&pdev->dev);
+       pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
+       pm_runtime_set_active(&pdev->dev);
+       pm_runtime_enable(&pdev->dev);
        /* QSPI controller initializations */
        zynqmp_qspi_init_hw(xqspi);
 
+       pm_runtime_mark_last_busy(&pdev->dev);
+       pm_runtime_put_autosuspend(&pdev->dev);
        xqspi->irq = platform_get_irq(pdev, 0);
        if (xqspi->irq <= 0) {
                ret = -ENXIO;
@@ -1063,6 +1113,8 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
        return 0;
 
 clk_dis_all:
+       pm_runtime_set_suspended(&pdev->dev);
+       pm_runtime_disable(&pdev->dev);
        clk_disable_unprepare(xqspi->refclk);
 clk_dis_pclk:
        clk_disable_unprepare(xqspi->pclk);
@@ -1090,6 +1142,8 @@ static int zynqmp_qspi_remove(struct platform_device *pdev)
        zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
        clk_disable_unprepare(xqspi->refclk);
        clk_disable_unprepare(xqspi->pclk);
+       pm_runtime_set_suspended(&pdev->dev);
+       pm_runtime_disable(&pdev->dev);
 
        spi_unregister_master(master);