Hi Lukasz,
On 04/23/2018 12:31 AM, Lukasz Majewski wrote:
> From: Stanislav Meduna <stanislav.meduna@xxxxxxxxxxxxxx>
>
> On a TQMa53 module the mmc_sleep leaves the eMMC card in a state
> that the imx53 rom boot code is unable to probe, resulting in
> reboot hanging. Add a device tree property to disable sleeping
> on suspend.
>
> For TQMa53 modules the exact commit to cause hang after reboot
> (v3.10 -> v3.11):
> commit 486fdbbc1483 ("mmc: core: Add shutdown callback for (e)MMC bus_ops")
>
> [The exact discussion can be found here:
> https://patchwork.kernel.org/patch/8881401/
> "i.MX53 restart via watchdog does not work"
>
> Signed-off-by: Stanislav Meduna <stanislav.meduna@xxxxxxxxxxxxxx>
> Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>
> ---
> Documentation/devicetree/bindings/mmc/mmc-card.txt | 4 ++++
> drivers/mmc/core/mmc.c | 7 +++++--
> include/linux/mmc/card.h | 2 +-
> 3 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/mmc-card.txt b/Documentation/devicetree/bindings/mmc/mmc-card.txt
> index 8d2d71758907..c3ee151edd7c 100644
> --- a/Documentation/devicetree/bindings/mmc/mmc-card.txt
> +++ b/Documentation/devicetree/bindings/mmc/mmc-card.txt
> @@ -12,6 +12,9 @@ Required properties:
> Optional properties:
> -broken-hpi : Use this to indicate that the mmc-card has a broken hpi
> implementation, and that hpi should not be used
> +-no-sleep-on-suspend : Do not put the card to sleep when suspending.
> + There are boards with bootloaders that are unable
> + to probe such card when rebooting.
I would recommend to examine an option to reuse the existing host
controller property 'keep-power-in-suspend', note that a particular
host controller driver may ignore it.
In general the problem sounds like a PCB hardware bug, and if it is
eMMC card specific, please provide more information about that eMMC
rather than about the host.
--
With best wishes,
Vladimir
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
