[PATCH v3 2/2] mtd: nand: raw: gpmi: improve power management handling

[Han Xu]

Refactor the power management handling in the gpmi nand driver. Remove
redundant pm_runtime calls in the driver probe function. Handle the pad
control and use the leverage runtime suspend and resume calls to take
care of clocks in system suspend and resume functions.

Signed-off-by: Han Xu <han.xu at nxp.com>
---
Changes in v3:
- Delet the DMA channel acquire/release in runtime pm ops.
- keep DMA channel acquire in driver probe.
- Refine the commit message

Changes in v2:
- none
---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 57 ++++++++++++----------
 1 file changed, 32 insertions(+), 25 deletions(-)

diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
index a7d79679248d..cab6d7b4f4dd 100644
--- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
@@ -15,6 +15,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/dma/mxs-dma.h>
 #include "gpmi-nand.h"
 #include "gpmi-regs.h"
@@ -737,9 +738,8 @@ static int bch_set_geometry(struct gpmi_nand_data *this)
 	if (ret)
 		return ret;
 
-	ret = pm_runtime_get_sync(this->dev);
+	ret = pm_runtime_resume_and_get(this->dev);
 	if (ret < 0) {
-		pm_runtime_put_autosuspend(this->dev);
 		return ret;
 	}
 
@@ -2761,15 +2761,9 @@ static int gpmi_nand_probe(struct platform_device *pdev)
 	if (ret)
 		goto exit_acquire_resources;
 
-	ret = __gpmi_enable_clk(this, true);
-	if (ret)
-		goto exit_acquire_resources;
-
+	pm_runtime_enable(&pdev->dev);
 	pm_runtime_set_autosuspend_delay(&pdev->dev, 500);
 	pm_runtime_use_autosuspend(&pdev->dev);
-	pm_runtime_set_active(&pdev->dev);
-	pm_runtime_enable(&pdev->dev);
-	pm_runtime_get_sync(&pdev->dev);
 
 	ret = gpmi_init(this);
 	if (ret)
@@ -2779,15 +2773,12 @@ static int gpmi_nand_probe(struct platform_device *pdev)
 	if (ret)
 		goto exit_nfc_init;
 
-	pm_runtime_mark_last_busy(&pdev->dev);
-	pm_runtime_put_autosuspend(&pdev->dev);
-
 	dev_info(this->dev, "driver registered.\n");
 
 	return 0;
 
 exit_nfc_init:
-	pm_runtime_put(&pdev->dev);
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	release_resources(this);
 exit_acquire_resources:
@@ -2801,22 +2792,23 @@ static void gpmi_nand_remove(struct platform_device *pdev)
 	struct nand_chip *chip = &this->nand;
 	int ret;
 
-	pm_runtime_put_sync(&pdev->dev);
-	pm_runtime_disable(&pdev->dev);
-
 	ret = mtd_device_unregister(nand_to_mtd(chip));
 	WARN_ON(ret);
 	nand_cleanup(chip);
 	gpmi_free_dma_buffer(this);
 	release_resources(this);
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
 }
 
 static int gpmi_pm_suspend(struct device *dev)
 {
-	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
 
-	release_dma_channels(this);
-	return 0;
+	pinctrl_pm_select_sleep_state(dev);
+	ret = pm_runtime_force_suspend(dev);
+
+	return ret;
 }
 
 static int gpmi_pm_resume(struct device *dev)
@@ -2824,9 +2816,13 @@ static int gpmi_pm_resume(struct device *dev)
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
 	int ret;
 
-	ret = acquire_dma_channels(this);
-	if (ret < 0)
+	ret = pm_runtime_force_resume(dev);
+	if (ret) {
+		dev_err(this->dev, "Error in resume %d\n", ret);
 		return ret;
+	}
+
+	pinctrl_pm_select_default_state(dev);
 
 	/* re-init the GPMI registers */
 	ret = gpmi_init(this);
@@ -2849,18 +2845,29 @@ static int gpmi_pm_resume(struct device *dev)
 	return 0;
 }
 
-static int __maybe_unused gpmi_runtime_suspend(struct device *dev)
+#define gpmi_enable_clk(x)	__gpmi_enable_clk(x, true)
+#define gpmi_disable_clk(x)	__gpmi_enable_clk(x, false)
+
+static int gpmi_runtime_suspend(struct device *dev)
 {
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
 
-	return __gpmi_enable_clk(this, false);
+	gpmi_disable_clk(this);
+
+	return 0;
 }
 
-static int __maybe_unused gpmi_runtime_resume(struct device *dev)
+static int gpmi_runtime_resume(struct device *dev)
 {
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
+
+	ret = gpmi_enable_clk(this);
+	if (ret)
+		return ret;
+
+	return 0;
 
-	return __gpmi_enable_clk(this, true);
 }
 
 static const struct dev_pm_ops gpmi_pm_ops = {
-- 
2.34.1