Re: [PATCH] mmc: spi: Fix card detection during probe

From: Ulf Hansson
Date: Tue Feb 26 2019 - 03:18:46 EST


On Sun, 10 Feb 2019 at 18:31, Jonathan NeuschÃfer <j.neuschaefer@xxxxxxx> wrote:
>
> When using the mmc_spi driver with a card-detect pin, I noticed that the
> card was not detected immediately after probe, but only after it was
> unplugged and plugged back in (and the CD IRQ fired).
>
> The call tree looks something like this:
>
> mmc_spi_probe
> mmc_add_host
> mmc_start_host
> _mmc_detect_change
> mmc_schedule_delayed_work(&host->detect, 0)
> mmc_rescan
> host->bus_ops->detect(host)
> mmc_detect
> _mmc_detect_card_removed
> host->ops->get_cd(host)
> mmc_gpio_get_cd -> -ENOSYS (ctx->cd_gpio not set)
> mmc_gpiod_request_cd
> ctx->cd_gpio = desc
>
> To fix this issue, call mmc_detect_change after the card-detect GPIO/IRQ
> is registered.
>
> Signed-off-by: Jonathan NeuschÃfer <j.neuschaefer@xxxxxxx>

This works well as fix and for stable! However, we should probably
clean up the code in ->probe() to avoid this thing altogether. Anyway,
I send a patch for that - on top.

Applied for fixes and added a stable tag, thanks!

Kind regards
Uffe


> ---
> drivers/mmc/host/mmc_spi.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
> index 10ba46b728e8..8ade14fb2148 100644
> --- a/drivers/mmc/host/mmc_spi.c
> +++ b/drivers/mmc/host/mmc_spi.c
> @@ -1450,6 +1450,7 @@ static int mmc_spi_probe(struct spi_device *spi)
> mmc->caps &= ~MMC_CAP_NEEDS_POLL;
> mmc_gpiod_request_cd_irq(mmc);
> }
> + mmc_detect_change(mmc, 0);
>
> /* Index 1 is write protect/read only */
> status = mmc_gpiod_request_ro(mmc, NULL, 1, false, 0, NULL);
> --
> 2.20.1
>