Re: [PATCH] mmc: mediatek: Add system suspend/resume interface

Ulf Hansson
2020-11-23T16:07:46Z

On Wed, 18 Nov 2020 at 07:34, Wenbin Mei <wenbin.mei@mediatek.com> wrote:
>
> Before we got these errors on MT8192 platform:
> [ 59.153891] Restarting tasks ...
> [ 59.154540] done.
> [ 59.159175] PM: suspend exit
> [ 59.218724] mtk-msdc 11f60000.mmc: phase: [map:fffffffe] [maxlen:31]
> [final:16]
> [ 119.776083] mmc0: cqhci: timeout for tag 9
> [ 119.780196] mmc0: cqhci: ============ CQHCI REGISTER DUMP ===========
> [ 119.786709] mmc0: cqhci: Caps: 0x100020b6 | Version: 0x00000510
> [ 119.793225] mmc0: cqhci: Config: 0x00000101 | Control: 0x00000000
> [ 119.799706] mmc0: cqhci: Int stat: 0x00000000 | Int enab: 0x00000000
> [ 119.806177] mmc0: cqhci: Int sig: 0x00000000 | Int Coal: 0x00000000
> [ 119.812670] mmc0: cqhci: TDL base: 0x00000000 | TDL up32: 0x00000000
> [ 119.819149] mmc0: cqhci: Doorbell: 0x003ffc00 | TCN: 0x00000200
> [ 119.825656] mmc0: cqhci: Dev queue: 0x00000000 | Dev Pend: 0x00000000
> [ 119.832155] mmc0: cqhci: Task clr: 0x00000000 | SSC1: 0x00001000
> [ 119.838627] mmc0: cqhci: SSC2: 0x00000000 | DCMD rsp: 0x00000000
> [ 119.845174] mmc0: cqhci: RED mask: 0xfdf9a080 | TERRI: 0x0000891c
> [ 119.851654] mmc0: cqhci: Resp idx: 0x00000000 | Resp arg: 0x00000000
> [ 119.865773] mmc0: cqhci: : ===========================================
> [ 119.872358] mmc0: running CQE recovery
> From these logs, we found TDL base was back to the default value.
>
> After suspend, the mmc host is powered off by HW, and bring CQE register
> to the default value, so we add system suspend/resume interface, then bring
> CQE to deactivated state before suspend, it will be enabled by CQE first
> request after resume.
>
> Signed-off-by: Wenbin Mei <wenbin.mei@mediatek.com>

I took the liberty of renaming msdc_sys_suspend|resume to
msdc_suspend|resume, as I think the "_sys" is a bit superfluous.

Additionally, I added a fixes+stable tag, then I applied this for fixes, thanks!

Please tell me, if there is anything you would like me to change.

Kind regards
Uffe

> ---
> drivers/mmc/host/mtk-sd.c | 22 ++++++++++++++++++++--
> 1 file changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index fc5ee5df91ad..c5f9cd6fc951 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -2758,11 +2758,29 @@ static int msdc_runtime_resume(struct device *dev)
> msdc_restore_reg(host);
> return 0;
> }
> +
> +static int msdc_sys_suspend(struct device *dev)
> +{
> + struct mmc_host *mmc = dev_get_drvdata(dev);
> + int ret;
> +
> + if (mmc->caps2 & MMC_CAP2_CQE) {
> + ret = cqhci_suspend(mmc);
> + if (ret)
> + return ret;
> + }
> +
> + return pm_runtime_force_suspend(dev);
> +}
> +
> +static int msdc_sys_resume(struct device *dev)
> +{
> + return pm_runtime_force_resume(dev);
> +}
> #endif
>
> static const struct dev_pm_ops msdc_dev_pm_ops = {
> - SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> - pm_runtime_force_resume)
> + SET_SYSTEM_SLEEP_PM_OPS(msdc_sys_suspend, msdc_sys_resume)
> SET_RUNTIME_PM_OPS(msdc_runtime_suspend, msdc_runtime_resume, NULL)
> };
>
> --
> 2.18.0