Re: [PATCH v2 04/11] mmc: host: omap_hsmmc: add code for special init of wl1251 to get rid of pandora_wl1251_init_card

[Ulf Hansson]

On Sat, 19 Oct 2019 at 20:42, H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> wrote:
>
> Pandora_wl1251_init_card was used to do special pdata based
> setup of the sdio mmc interface. This does no longer work with
> v4.7 and later. A fix requires a device tree based mmc3 setup.
>
> Therefore we move the special setup to omap_hsmmc.c instead
> of calling some pdata supplied init_card function.
>
> The new code checks for a DT child node compatible to wl1251
> so it will not affect other MMC3 use cases.
>
> Fixes: 81eef6ca9201 ("mmc: omap_hsmmc: Use dma_request_chan() for requesting DMA channel")
>
> Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # 4.7.0
> ---
>  drivers/mmc/host/omap_hsmmc.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 952fa4063ff8..03ba80bcf319 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -1512,6 +1512,27 @@ static void omap_hsmmc_init_card(struct mmc_host *mmc, struct mmc_card *card)
>
>         if (mmc_pdata(host)->init_card)
>                 mmc_pdata(host)->init_card(card);
> +       else if (card->type == MMC_TYPE_SDIO || card->type == MMC_TYPE_SD_COMBO) {
> +               struct device_node *np = mmc_dev(mmc)->of_node;
> +
> +               np = of_get_compatible_child(np, "ti,wl1251");
> +               if (np) {
> +                       /*
> +                        * We have TI wl1251 attached to MMC3. Pass this information to
> +                        * SDIO core because it can't be probed by normal methods.
> +                        */
> +
> +                       dev_info(host->dev, "found wl1251\n");
> +                       card->quirks |= MMC_QUIRK_NONSTD_SDIO;
> +                       card->cccr.wide_bus = 1;
> +                       card->cis.vendor = 0x104c;
> +                       card->cis.device = 0x9066;
> +                       card->cis.blksize = 512;
> +                       card->cis.max_dtr = 24000000;
> +                       card->ocr = 0x80;

These things should really be figured out by the mmc core during SDIO
card initialization itself, not via the host ops ->init_card()
callback. That is just poor hack, which in the long run should go
away.

Moreover, I think we should add a subnode to the host node in the DT,
to describe the embedded SDIO card, rather than parsing the subnode
for the SDIO func - as that seems wrong to me.

To add a subnode for the SDIO card, we already have a binding that I
think we should extend. Please have a look at
Documentation/devicetree/bindings/mmc/mmc-card.txt.

If you want an example of how to implement this for your case, do a
git grep "broken-hpi" in the driver/mmc/core/, I think it will tell
you more of what I have in mind.

> +                       of_node_put(np);
> +               }
> +       }
>  }
>
>  static void omap_hsmmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
> --
> 2.19.1
>

Kind regards
Uffe