target/linux/s3c24xx/patches-2.6.26/1251-My-GTA01-2.6.26-kernel-was-crashing-within-mmc_power.patch

   1 From 0733a2e1b598dec898fef5066b737764170aaf62 Mon Sep 17 00:00:00 2001
   2 From: Andy Green <agreen@pads.home.warmcat.com>
   3 Date: Sun, 10 Aug 2008 09:27:16 +0100
   4 Subject: [PATCH] My GTA01 2.6.26 kernel was crashing within mmc_power_up(), at the first
   5  call to mmc_set_ios(host), due to host->ops being NULL. mmc_power_up()
   6  was being called by mmc_rescan().
   7
   8 The only possible call path I can imagine for that is s3cmci_irq_cd
   9 getting called before host->ops is set, thus calling mmc_detect_change()
  10 which will schedule host->detect which is mmc_rescan.
  11
  12 This patch avoids the problem by moving the enable of the gpio_detect
  13 interrupt to just before calling mmc_add_host(), where everything else
  14 is already set up.
  15
  16 Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
  17 ---
  18  drivers/mmc/host/s3cmci.c |   34 +++++++++++++++++-----------------
  19  1 files changed, 17 insertions(+), 17 deletions(-)
  20
  21 diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c
  22 index 9ef4d5b..107847a 100644
  23 --- a/drivers/mmc/host/s3cmci.c
  24 +++ b/drivers/mmc/host/s3cmci.c
  25 @@ -1226,17 +1226,6 @@ static int s3cmci_probe(struct platform_device *pdev, int is2440)
  26
  27         disable_irq(host->irq);
  28
  29 -       s3c2410_gpio_cfgpin(host->pdata->gpio_detect, S3C2410_GPIO_IRQ);
  30 -       set_irq_type(host->irq_cd, IRQT_BOTHEDGE);
  31 -
  32 -       if (request_irq(host->irq_cd, s3cmci_irq_cd, 0, DRIVER_NAME, host)) {
  33 -               dev_err(&pdev->dev,
  34 -                       "failed to request card detect interrupt.\n");
  35 -
  36 -               ret = -ENOENT;
  37 -               goto probe_free_irq;
  38 -       }
  39 -
  40         if (host->pdata->gpio_wprotect)
  41                 s3c2410_gpio_cfgpin(host->pdata->gpio_wprotect,
  42                                     S3C2410_GPIO_INPUT);
  43 @@ -1244,7 +1233,7 @@ static int s3cmci_probe(struct platform_device *pdev, int is2440)
  44         if (s3c2410_dma_request(host->dma, &s3cmci_dma_client, NULL)) {
  45                 dev_err(&pdev->dev, "unable to get DMA channel.\n");
  46                 ret = -EBUSY;
  47 -               goto probe_free_irq_cd;
  48 +               goto probe_free_irq;
  49         }
  50
  51         host->clk = clk_get(&pdev->dev, "sdi");
  52 @@ -1281,10 +1270,21 @@ static int s3cmci_probe(struct platform_device *pdev, int is2440)
  53             "irq_cd:%u dma:%u.\n", (host->is2440?"2440":""),
  54             host->base, host->irq, host->irq_cd, host->dma);
  55
  56 +       s3c2410_gpio_cfgpin(host->pdata->gpio_detect, S3C2410_GPIO_IRQ);
  57 +       set_irq_type(host->irq_cd, IRQT_BOTHEDGE);
  58 +
  59 +       if (request_irq(host->irq_cd, s3cmci_irq_cd, 0, DRIVER_NAME, host)) {
  60 +               dev_err(&pdev->dev,
  61 +                       "failed to request card detect interrupt.\n");
  62 +
  63 +               ret = -ENOENT;
  64 +               goto probe_disable_clk;
  65 +       }
  66 +
  67         ret = mmc_add_host(mmc);
  68         if (ret) {
  69                 dev_err(&pdev->dev, "failed to add mmc host.\n");
  70 -               goto probe_disable_clk;
  71 +               goto probe_free_irq_cd;
  72         }
  73
  74         platform_set_drvdata(pdev, mmc);
  75 @@ -1292,15 +1292,15 @@ static int s3cmci_probe(struct platform_device *pdev, int is2440)
  76         dev_info(&pdev->dev, "initialisation done.\n");
  77         return 0;
  78
  79 + probe_free_irq_cd:
  80 +       free_irq(host->irq_cd, host);
  81 +
  82   probe_disable_clk:
  83         clk_disable(host->clk);
  84
  85   probe_free_clk:
  86         clk_put(host->clk);
  87
  88 - probe_free_irq_cd:
  89 -       free_irq(host->irq_cd, host);
  90 -
  91   probe_free_dma:
  92         s3c2410_dma_free(host->dma, &s3cmci_dma_client);
  93
  94 @@ -1325,10 +1325,10 @@ static int s3cmci_remove(struct platform_device *pdev)
  95         struct s3cmci_host      *host = mmc_priv(mmc);
  96
  97         mmc_remove_host(mmc);
  98 +       free_irq(host->irq_cd, host);
  99         clk_disable(host->clk);
 100         clk_put(host->clk);
 101         s3c2410_dma_free(host->dma, &s3cmci_dma_client);
 102 -       free_irq(host->irq_cd, host);
 103         free_irq(host->irq, host);
 104         iounmap(host->base);
 105         release_mem_region(host->mem->start, RESSIZE(host->mem));
 106 --
 107 1.5.6.3
 108