From: Esben Haabendal <esben@geanix.com>
To: Han Xu <han.xu@nxp.com>
Cc: vigneshr@ti.com, richard@nod.at, s.hauer@pengutronix.de,
sean@geanix.com, martin@geanix.com,
boris.brezillon@collabora.com, linux-mtd@lists.infradead.org,
miquel.raynal@bootlin.com
Subject: Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue
Date: Thu, 09 Jan 2020 21:45:58 +0100 [thread overview]
Message-ID: <87r208mk8p.fsf@geanix.com> (raw)
In-Reply-To: <1578589556-683-1-git-send-email-han.xu@nxp.com> (Han Xu's message of "Fri, 10 Jan 2020 01:05:56 +0800")
Hi Han
See comments/questions below.
If I understand the purpose of some of your changes correct, you are
fixing the handling of pm usage counter, as it currently is incremented
in gpmi_init() and decremented in gpmi_nand_remove(). I believe that
would be nice to have in a separate patch with an explanation of the
change.
Han Xu <han.xu@nxp.com> writes:
> fix several issues when system suspend/resume,
>
> - leverage the runtime pm for system suspend/resume
> - enable the clock before register access
> - re-apply timing settings
> - set the proper pinctrl state
>
> Signed-off-by: Han Xu <han.xu@nxp.com>
> ---
> drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 59 ++++++++++++++++------
> 1 file changed, 44 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 334fe3130285..37437d47ab9a 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/of_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"
> @@ -146,7 +147,11 @@ static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
> static int gpmi_init(struct gpmi_nand_data *this)
> {
> struct resources *r = &this->resources;
> - int ret;
> + int ret = 0;
I don't see why this is changed, given that ret is unconditionally
assigned in the next line.
> +
> + ret = pm_runtime_get_sync(this->dev);
> + if (ret < 0)
> + return ret;
>
> ret = gpmi_reset_block(r->gpmi_regs, false);
> if (ret)
> @@ -179,8 +184,10 @@ static int gpmi_init(struct gpmi_nand_data *this)
> */
> writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
>
> - return 0;
Please provide an explanation of the reasoning of this change is.
> err_out:
> + pm_runtime_mark_last_busy(this->dev);
> + pm_runtime_put_autosuspend(this->dev);
> +
> return ret;
> }
>
> @@ -528,7 +535,7 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
> static int bch_set_geometry(struct gpmi_nand_data *this)
> {
> struct resources *r = &this->resources;
> - int ret;
> + int ret = 0;
I don't see any reason for this change.
> ret = common_nfc_set_geometry(this);
> if (ret)
> @@ -2676,7 +2682,7 @@ static int gpmi_nand_probe(struct platform_device *pdev)
> return 0;
>
> exit_nfc_init:
> - pm_runtime_put(&pdev->dev);
I guess this is because of the change above that causes usage counter
not to be incremented in gpmi_init() when it is successful.
> + pm_runtime_dont_use_autosuspend(&pdev->dev);
Is this required before pm_runtime_disable()?
> pm_runtime_disable(&pdev->dev);
> release_resources(this);
> exit_acquire_resources:
> @@ -2688,7 +2694,6 @@ static int gpmi_nand_remove(struct platform_device *pdev)
> {
> struct gpmi_nand_data *this = platform_get_drvdata(pdev);
>
> - pm_runtime_put_sync(&pdev->dev);
Should be covered by explanation of the change in gpmi_init().
> pm_runtime_disable(&pdev->dev);
>
> nand_release(&this->nand);
> @@ -2700,10 +2705,12 @@ static int gpmi_nand_remove(struct platform_device *pdev)
> #ifdef CONFIG_PM_SLEEP
> 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)
> @@ -2711,9 +2718,13 @@ 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);
> @@ -2729,22 +2740,40 @@ static int gpmi_pm_resume(struct device *dev)
> return ret;
> }
>
> + /* re-apply the timing setting */
> + this->hw.must_apply_timings = true;
> +
> return 0;
> }
> #endif /* CONFIG_PM_SLEEP */
>
> -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;
>
> - return __gpmi_enable_clk(this, true);
> + ret = gpmi_enable_clk(this);
> + if (ret)
> + return ret;
> +
> + ret = acquire_dma_channels(this);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> }
>
> static const struct dev_pm_ops gpmi_pm_ops = {
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next prev parent reply other threads:[~2020-01-09 20:46 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-09 17:05 [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue Han Xu
2020-01-09 19:01 ` Miquel Raynal
2020-01-09 20:06 ` Esben Haabendal
2020-01-09 20:09 ` Han Xu
2020-01-13 17:30 ` Miquel Raynal
2020-01-09 20:45 ` Esben Haabendal [this message]
2020-01-14 21:53 ` Han Xu
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