target/linux/goldfish/patches-2.6.30/0094-mmc-sd-Add-new-CONFIG_MMC_PARANOID_SD_INIT-for-ena.patch

   1 From 66983857a54479d76ce6dbd8399e1276698bd3c5 Mon Sep 17 00:00:00 2001
   2 From: San Mehat <san@google.com>
   3 Date: Tue, 11 Nov 2008 09:35:36 -0800
   4 Subject: [PATCH 094/134] mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection
   5
   6 Signed-off-by: San Mehat <san@google.com>
   7 ---
   8  drivers/mmc/core/Kconfig |    8 ++++++++
   9  drivers/mmc/core/sd.c    |   24 ++++++++++++++++++++++--
  10  2 files changed, 30 insertions(+), 2 deletions(-)
  11
  12 --- a/drivers/mmc/core/Kconfig
  13 +++ b/drivers/mmc/core/Kconfig
  14 @@ -14,3 +14,11 @@ config MMC_UNSAFE_RESUME
  15           This option is usually just for embedded systems which use
  16           a MMC/SD card for rootfs. Most people should say N here.
  17
  18 +config MMC_PARANOID_SD_INIT
  19 +       bool "Enable paranoid SD card initialization (EXPERIMENTAL)"
  20 +       help
  21 +         If you say Y here, the MMC layer will be extra paranoid
  22 +         about re-trying SD init requests. This can be a useful
  23 +         work-around for buggy controllers and hardware. Enable
  24 +         if you are experiencing issues with SD detection.
  25 +
  26 --- a/drivers/mmc/core/sd.c
  27 +++ b/drivers/mmc/core/sd.c
  28 @@ -336,7 +336,9 @@ static int mmc_sd_init_card(struct mmc_h
  29         int err;
  30         u32 cid[4];
  31         unsigned int max_dtr;
  32 -
  33 +#ifdef CONFIG_MMC_PARANOID_SD_INIT
  34 +       int retries;
  35 +#endif
  36         BUG_ON(!host);
  37         WARN_ON(!host->claimed);
  38
  39 @@ -439,11 +441,29 @@ static int mmc_sd_init_card(struct mmc_h
  40                 err = mmc_decode_scr(card);
  41                 if (err < 0)
  42                         goto free_card;
  43 -
  44                 /*
  45                  * Fetch switch information from card.
  46                  */
  47 +#ifdef CONFIG_MMC_PARANOID_SD_INIT
  48 +               for (retries = 1; retries <= 3; retries++) {
  49 +                       err = mmc_read_switch(card);
  50 +                       if (!err) {
  51 +                               if (retries > 1) {
  52 +                                       printk(KERN_WARNING
  53 +                                              "%s: recovered\n",
  54 +                                              mmc_hostname(host));
  55 +                               }
  56 +                               break;
  57 +                       } else {
  58 +                               printk(KERN_WARNING
  59 +                                      "%s: read switch failed (attempt %d)\n",
  60 +                                      mmc_hostname(host), retries);
  61 +                       }
  62 +               }
  63 +#else
  64                 err = mmc_read_switch(card);
  65 +#endif
  66 +
  67                 if (err)
  68                         goto free_card;
  69         }