[PATCH v2 2/2] mtd: nand: raw: gpmi: improve power management handling

Han Xu
2024-10-02T15:44:08Z

The commit refactors the power management handling in the gpmi nand
driver. It removes redundant pm_runtime calls in the probe function,
handles the pad control in suspend and resume, and moves the calls to
acquire and release DMA channels to the runtime suspend and resume
functions.

Signed-off-by: Han Xu <han.xu@nxp.com>
---
drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 66 ++++++++++++----------
1 file changed, 37 insertions(+), 29 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..76e4b89e2451 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;
}

@@ -1301,10 +1301,6 @@ static int acquire_resources(struct gpmi_nand_data *this)
if (ret)
goto exit_regs;

- ret = acquire_dma_channels(this);
- if (ret)
- goto exit_regs;
-
ret = gpmi_get_clks(this);
if (ret)
goto exit_clock;
@@ -2761,15 +2757,9 @@ 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 +2769,12 @@ 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 +2788,23 @@ 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 +2812,13 @@ 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 +2841,34 @@ 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);
+ release_dma_channels(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;
+
+ ret = acquire_dma_channels(this);
+ if (ret < 0)
+ return ret;
+
+ return 0;

- return __gpmi_enable_clk(this, true);
}

static const struct dev_pm_ops gpmi_pm_ops = {
--
2.34.1