1. 26 Jan, 2016 1 commit
    • Martin Wilck's avatar
      base/platform: Fix platform drivers with no probe callback · 25cad69f
      Martin Wilck authored
      Since b8b2c7d8, platform_drv_probe() is called for all platform
      devices. If drv->probe is NULL, and dev_pm_domain_attach() fails,
      platform_drv_probe() will return the error code from dev_pm_domain_attach().
      
      This causes real_probe() to enter the "probe_failed" path and set
      dev->driver to NULL. Before b8b2c7d8, real_probe() would assume
      success if both dev->bus->probe and drv->probe were missing. As a result,
      a device and driver could be "bound" together just by matching their names;
      this doesn't work any more after b8b2c7d8.
      
      This may cause problems later for certain usage of platform_driver_register()
      and platform_device_register_simple(). I observed a panic while loading
      the tpm_tis driver with parameter "force=1" (i.e. registering tpm_tis as
      a platform driver), because tpm_tis_init's assumption that the device
      returned by platform_device_register_simple() was bound didn't hold any more
      (tpmm_chip_alloc() dereferences chip->pdev->driver, causing panic).
      
      This patch restores the previous (4.3.0 and earlier) behavior of
      platform_drv_probe() in the case when the associated platform driver has
      no "probe" function.
      
      Fixes: b8b2c7d8 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally")
      Signed-off-by: default avatarMartin Wilck <Martin.Wilck@ts.fujitsu.com>
      Cc: stable <stable@vger.kernel.org> # 4.4
      Cc: Martin Fuzzey <mfuzzey@parkeon.com>
      Acked-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      25cad69f
  2. 24 Jan, 2016 39 commits