target/linux/goldfish/patches-2.6.30/0099-mmc-mmcblk-Add-new-feature-CONFIG_MMC_BLOCK_PARAN.patch

   1 From 5ca694dfd981a371e9b18cdd4a89c002ffaccbc5 Mon Sep 17 00:00:00 2001
   2 From: San Mehat <san@android.com>
   3 Date: Wed, 3 Dec 2008 10:22:59 -0800
   4 Subject: [PATCH 099/134] mmc: mmcblk: Add new feature 'CONFIG_MMC_BLOCK_PARANOID_RESUME'
   5
   6   With this feature enabled, mmcblk will check the card-status before issuing
   7 a transaction *only* after being resumed. This protectes us from issuing
   8 transactions before the sdcard is ready (which can occur if the host driver
   9 deferrs mmc_resume_host() to reduce resume latency)
  10
  11 Signed-off-by: San Mehat <san@android.com>
  12 ---
  13  drivers/mmc/card/Kconfig |    7 +++++++
  14  drivers/mmc/card/block.c |    3 +++
  15  drivers/mmc/card/queue.c |   28 ++++++++++++++++++++++++++++
  16  drivers/mmc/card/queue.h |    3 +++
  17  4 files changed, 41 insertions(+), 0 deletions(-)
  18
  19 --- a/drivers/mmc/card/Kconfig
  20 +++ b/drivers/mmc/card/Kconfig
  21 @@ -32,6 +32,13 @@ config MMC_BLOCK_BOUNCE
  22
  23           If unsure, say Y here.
  24
  25 +config MMC_BLOCK_PARANOID_RESUME
  26 +       bool "Check card status on resume"
  27 +        depends on MMC_BLOCK
  28 +        default y
  29 +        help
  30 +          Nohelp
  31 +
  32  config SDIO_UART
  33         tristate "SDIO UART/GPS class support"
  34         help
  35 --- a/drivers/mmc/card/block.c
  36 +++ b/drivers/mmc/card/block.c
  37 @@ -643,6 +643,9 @@ static int mmc_blk_resume(struct mmc_car
  38
  39         if (md) {
  40                 mmc_blk_set_blksize(md, card);
  41 +#ifdef CONFIG_MMC_BLOCK_PARANOID_RESUME
  42 +               md->queue.check_status = 1;
  43 +#endif
  44                 mmc_queue_resume(&md->queue);
  45         }
  46         return 0;
  47 --- a/drivers/mmc/card/queue.c
  48 +++ b/drivers/mmc/card/queue.c
  49 @@ -14,7 +14,9 @@
  50  #include <linux/freezer.h>
  51  #include <linux/kthread.h>
  52  #include <linux/scatterlist.h>
  53 +#include <linux/delay.h>
  54
  55 +#include <linux/mmc/mmc.h>
  56  #include <linux/mmc/card.h>
  57  #include <linux/mmc/host.h>
  58  #include "queue.h"
  59 @@ -70,7 +72,33 @@ static int mmc_queue_thread(void *d)
  60                         continue;
  61                 }
  62                 set_current_state(TASK_RUNNING);
  63 +#ifdef CONFIG_MMC_BLOCK_PARANOID_RESUME
  64 +               if (mq->check_status) {
  65 +                       struct mmc_command cmd;
  66
  67 +                       do {
  68 +                               int err;
  69 +
  70 +                               cmd.opcode = MMC_SEND_STATUS;
  71 +                               cmd.arg = mq->card->rca << 16;
  72 +                               cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
  73 +
  74 +                               mmc_claim_host(mq->card->host);
  75 +                               err = mmc_wait_for_cmd(mq->card->host, &cmd, 5);
  76 +                               mmc_release_host(mq->card->host);
  77 +
  78 +                               if (err) {
  79 +                                       printk(KERN_ERR "%s: failed to get status (%d)\n",
  80 +                                              __func__, err);
  81 +                                       msleep(5);
  82 +                                       continue;
  83 +                               }
  84 +                               printk(KERN_DEBUG "%s: status 0x%.8x\n", __func__, cmd.resp[0]);
  85 +                       } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
  86 +                               (R1_CURRENT_STATE(cmd.resp[0]) == 7));
  87 +                       mq->check_status = 0;
  88 +                }
  89 +#endif
  90                 mq->issue_fn(mq, req);
  91         } while (1);
  92         up(&mq->thread_sem);
  93 --- a/drivers/mmc/card/queue.h
  94 +++ b/drivers/mmc/card/queue.h
  95 @@ -17,6 +17,9 @@ struct mmc_queue {
  96         char                    *bounce_buf;
  97         struct scatterlist      *bounce_sg;
  98         unsigned int            bounce_sg_len;
  99 +#ifdef CONFIG_MMC_BLOCK_PARANOID_RESUME
 100 +       int                     check_status;
 101 +#endif
 102  };
 103
 104  extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *);