target/linux/mxs/patches-3.14/130-mxs-mmc-fix-card-detect.patch

   1 From 91769986a724f63db52f3c78c79ac84a5b7045bf Mon Sep 17 00:00:00 2001
   2 From: Daniel Willmann <daniel@totalueberwachung.de>
   3 Date: Sat, 19 Apr 2014 23:59:18 +0200
   4 Subject: [PATCH] mmc: mxs: fix card detection function for broken card detect
   5
   6 Return -ENOSYS in get_cd if broken-cd is specified in the device tree.
   7
   8 Commit a91fe279ae75 (mmc: mxs: use standard flag for broken card
   9 detection) sets MMC_CAP_NEEDS_POLL when broken-cd is specified. This
  10 driver sets this flag unconditionally as it does not support a card
  11 detect interrupt. Instead, broken-cd means that there is no card detect
  12 signal connected.
  13
  14 The mmc core checks the get_cd function return value to determine if a
  15 card is present. Only for a non-zero return value it will attempt to
  16 initialize the card. So retuning -ENOSYS will allow the card to be
  17 initialized.
  18
  19 For comparison, mmc_gpio_get_cd in slot-gpio.c also returns -ENOSYS if
  20 the card detect GPIO is not valid.
  21
  22 Signed-off-by: Daniel Willmann <daniel@totalueberwachung.de>
  23 Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
  24 Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
  25 Signed-off-by: Chris Ball <chris@printf.net>
  26 ---
  27  drivers/mmc/host/mxs-mmc.c | 7 +++++++
  28  1 file changed, 7 insertions(+)
  29
  30 --- a/drivers/mmc/host/mxs-mmc.c
  31 +++ b/drivers/mmc/host/mxs-mmc.c
  32 @@ -70,6 +70,7 @@ struct mxs_mmc_host {
  33         unsigned char                   bus_width;
  34         spinlock_t                      lock;
  35         int                             sdio_irq_en;
  36 +       bool                            broken_cd;
  37  };
  38
  39  static int mxs_mmc_get_cd(struct mmc_host *mmc)
  40 @@ -78,6 +79,9 @@ static int mxs_mmc_get_cd(struct mmc_hos
  41         struct mxs_ssp *ssp = &host->ssp;
  42         int present, ret;
  43
  44 +       if (host->broken_cd)
  45 +               return -ENOSYS;
  46 +
  47         ret = mmc_gpio_get_cd(mmc);
  48         if (ret >= 0)
  49                 return ret;
  50 @@ -568,6 +572,7 @@ static int mxs_mmc_probe(struct platform
  51  {
  52         const struct of_device_id *of_id =
  53                         of_match_device(mxs_mmc_dt_ids, &pdev->dev);
  54 +       struct device_node *np = pdev->dev.of_node;
  55         struct mxs_mmc_host *host;
  56         struct mmc_host *mmc;
  57         struct resource *iores;
  58 @@ -634,6 +639,8 @@ static int mxs_mmc_probe(struct platform
  59         mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
  60                     MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL;
  61
  62 +       host->broken_cd = of_property_read_bool(np, "broken-cd");
  63 +
  64         mmc->f_min = 400000;
  65         mmc->f_max = 288000000;
  66