[PATCH] spi: imx: enable runtime pm support

[Clark Wang]

Enable runtime pm support for spi-imx driver.

Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
---
 drivers/spi/spi-imx.c | 121 ++++++++++++++++++++++++++++++------------
 1 file changed, 88 insertions(+), 33 deletions(-)

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index fdc25f549378..38a5f1304cec 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -13,7 +13,9 @@
 #include <linux/irq.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/spi_bitbang.h>
@@ -30,6 +32,8 @@ static bool use_dma = true;
 module_param(use_dma, bool, 0644);
 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
 
+#define MXC_RPM_TIMEOUT		2000 /* 2000ms */
+
 #define MXC_CSPIRXDATA		0x00
 #define MXC_CSPITXDATA		0x04
 #define MXC_CSPICTRL		0x08
@@ -1530,20 +1534,16 @@ spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 	int ret;
 
-	ret = clk_enable(spi_imx->clk_per);
-	if (ret)
-		return ret;
-
-	ret = clk_enable(spi_imx->clk_ipg);
-	if (ret) {
-		clk_disable(spi_imx->clk_per);
+	ret = pm_runtime_get_sync(spi_imx->dev);
+	if (ret < 0) {
+		dev_err(spi_imx->dev, "failed to enable clock\n");
 		return ret;
 	}
 
 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
 	if (ret) {
-		clk_disable(spi_imx->clk_ipg);
-		clk_disable(spi_imx->clk_per);
+		pm_runtime_mark_last_busy(spi_imx->dev);
+		pm_runtime_put_autosuspend(spi_imx->dev);
 	}
 
 	return ret;
@@ -1554,8 +1554,8 @@ spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
 {
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 
-	clk_disable(spi_imx->clk_ipg);
-	clk_disable(spi_imx->clk_per);
+	pm_runtime_mark_last_busy(spi_imx->dev);
+	pm_runtime_put_autosuspend(spi_imx->dev);
 	return 0;
 }
 
@@ -1674,13 +1674,15 @@ static int spi_imx_probe(struct platform_device *pdev)
 		goto out_master_put;
 	}
 
-	ret = clk_prepare_enable(spi_imx->clk_per);
-	if (ret)
-		goto out_master_put;
+	pm_runtime_enable(spi_imx->dev);
+	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(spi_imx->dev);
 
-	ret = clk_prepare_enable(spi_imx->clk_ipg);
-	if (ret)
-		goto out_put_per;
+	ret = pm_runtime_get_sync(spi_imx->dev);
+	if (ret < 0) {
+		dev_err(spi_imx->dev, "failed to enable clock\n");
+		goto out_runtime_pm_put;
+	}
 
 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
 	/*
@@ -1690,7 +1692,7 @@ static int spi_imx_probe(struct platform_device *pdev)
 	if (spi_imx->devtype_data->has_dmamode) {
 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
 		if (ret == -EPROBE_DEFER)
-			goto out_clk_put;
+			goto out_runtime_pm_put;
 
 		if (ret < 0)
 			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
@@ -1705,19 +1707,20 @@ static int spi_imx_probe(struct platform_device *pdev)
 	ret = spi_bitbang_start(&spi_imx->bitbang);
 	if (ret) {
 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
-		goto out_clk_put;
+		goto out_runtime_pm_put;
 	}
 
 	dev_info(&pdev->dev, "probed\n");
 
-	clk_disable(spi_imx->clk_ipg);
-	clk_disable(spi_imx->clk_per);
+	pm_runtime_mark_last_busy(spi_imx->dev);
+	pm_runtime_put_autosuspend(spi_imx->dev);
+
 	return ret;
 
-out_clk_put:
-	clk_disable_unprepare(spi_imx->clk_ipg);
-out_put_per:
-	clk_disable_unprepare(spi_imx->clk_per);
+out_runtime_pm_put:
+	pm_runtime_dont_use_autosuspend(spi_imx->dev);
+	pm_runtime_put_sync(spi_imx->dev);
+	pm_runtime_disable(spi_imx->dev);
 out_master_put:
 	spi_master_put(master);
 
@@ -1732,30 +1735,82 @@ static int spi_imx_remove(struct platform_device *pdev)
 
 	spi_bitbang_stop(&spi_imx->bitbang);
 
-	ret = clk_enable(spi_imx->clk_per);
+	ret = pm_runtime_get_sync(spi_imx->dev);
+	if (ret < 0) {
+		dev_err(spi_imx->dev, "failed to enable clock\n");
+		return ret;
+	}
+
+	writel(0, spi_imx->base + MXC_CSPICTRL);
+
+	pm_runtime_dont_use_autosuspend(spi_imx->dev);
+	pm_runtime_put_sync(spi_imx->dev);
+	pm_runtime_disable(spi_imx->dev);
+
+	spi_imx_sdma_exit(spi_imx);
+	spi_master_put(master);
+
+	return 0;
+}
+
+static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct spi_imx_data *spi_imx;
+	int ret;
+
+	spi_imx = spi_master_get_devdata(master);
+
+	ret = clk_prepare_enable(spi_imx->clk_per);
 	if (ret)
 		return ret;
 
-	ret = clk_enable(spi_imx->clk_ipg);
+	ret = clk_prepare_enable(spi_imx->clk_ipg);
 	if (ret) {
-		clk_disable(spi_imx->clk_per);
+		clk_disable_unprepare(spi_imx->clk_per);
 		return ret;
 	}
 
-	writel(0, spi_imx->base + MXC_CSPICTRL);
-	clk_disable_unprepare(spi_imx->clk_ipg);
+	return 0;
+}
+
+static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct spi_imx_data *spi_imx;
+
+	spi_imx = spi_master_get_devdata(master);
+
 	clk_disable_unprepare(spi_imx->clk_per);
-	spi_imx_sdma_exit(spi_imx);
-	spi_master_put(master);
+	clk_disable_unprepare(spi_imx->clk_ipg);
+
+	return 0;
+}
 
+static int __maybe_unused spi_imx_suspend(struct device *dev)
+{
+	pinctrl_pm_select_sleep_state(dev);
 	return 0;
 }
 
+static int __maybe_unused spi_imx_resume(struct device *dev)
+{
+	pinctrl_pm_select_default_state(dev);
+	return 0;
+}
+
+static const struct dev_pm_ops imx_spi_pm = {
+	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
+				spi_imx_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
+};
+
 static struct platform_driver spi_imx_driver = {
 	.driver = {
 		   .name = DRIVER_NAME,
 		   .of_match_table = spi_imx_dt_ids,
-		   },
+		   .pm = &imx_spi_pm,
+	},
 	.id_table = spi_imx_devtype,
 	.probe = spi_imx_probe,
 	.remove = spi_imx_remove,
-- 
2.17.1