• Marek Szyprowski's avatar
    ASoC: max98090: fix incorrect helper in max98090_dapm_put_enum_double() · 4e93c129
    Marek Szyprowski authored
    Commit 62d5ae4c ("ASoC: max98090: save and restore SHDN when changing
    sensitive registers") extended the code for handling "LTENL Mux", "LTENR
    Mux", "LBENL Mux" and "LBENR Mux" controls by adding a custom
    max98090_dapm_put_enum_double() function to them. However that function
    used incorrect helper to get its component object. Fix this by using the
    proper snd_soc_dapm_* helper.
    
    This fixes the following NULL pointer exception observed on
    Exynos4412-based Odroid U3 board:
    8<--- cut here ---
    Unable to handle kernel NULL pointer dereference at virtual address 000000b0
    pgd = (ptrval)
    [000000b0] *pgd=00000000
    Internal error: Oops: 5 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 0 PID: 1104 Comm: alsactl Not tainted 5.5.0-rc5-next-20200107 #166
    Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
    PC is at __mutex_lock+0x54/0xb18
    LR is at ___might_sleep+0x3c/0x2e0
    ...
    Process alsactl (pid: 1104, stack limit = 0x(ptrval))
    ...
    [<c0b49630>] (__mutex_lock) from [<c0b4a110>] (mutex_lock_nested+0x1c/0x24)
    [<c0b4a110>] (mutex_lock_nested) from [<c0839b3c>] (max98090_shdn_save+0x1c/0x28)
    [<c0839b3c>] (max98090_shdn_save) from [<c083a4f8>] (max98090_dapm_put_enum_double+0x20/0x40)
    [<c083a4f8>] (max98090_dapm_put_enum_double) from [<c080d0e8>] (snd_ctl_ioctl+0x190/0xbb8)
    [<c080d0e8>] (snd_ctl_ioctl) from [<c02cafec>] (ksys_ioctl+0x470/0xaf8)
    [<c02cafec>] (ksys_ioctl) from [<c0101000>] (ret_fast_syscall+0x0/0x28)
    ...
    ---[ end trace 0e93f0580f4b9241 ]---
    
    Fixes: 62d5ae4c ("ASoC: max98090: save and restore SHDN when changing sensitive registers")
    Signed-off-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
    Reviewed-by: default avatarTzung-Bi Shih <tzungbi@google.com>
    Link: https://lore.kernel.org/r/20200108115007.31095-1-m.szyprowski@samsung.comSigned-off-by: default avatarMark Brown <broonie@kernel.org>
    4e93c129
max98090.c 90.8 KB