diff options
| author |   Brian Norris <briannorris@chromium.org> | 2019-07-29 13:49:54 -0700 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-30 13:46:15 +0200 |
| commit | 46c42d844211ef5902e32aa507beac0817c585e9 (patch) | |
| tree | d0e820be4c1f44a9514c0b323db6ae98e31bc7c4 /drivers/base | |
| parent | Linus 5.3-rc1 (diff) | |
| download | linux-dev-46c42d844211ef5902e32aa507beac0817c585e9.tar.xz linux-dev-46c42d844211ef5902e32aa507beac0817c585e9.zip | |
driver core: platform: return -ENXIO for missing GpioInt
Commit daaef255dc96 ("driver: platform: Support parsing GpioInt 0 in
platform_get_irq()") broke the Embedded Controller driver on most LPC
Chromebooks (i.e., most x86 Chromebooks), because cros_ec_lpc expects
platform_get_irq() to return -ENXIO for non-existent IRQs.
Unfortunately, acpi_dev_gpio_irq_get() doesn't follow this convention
and returns -ENOENT instead. So we get this error from cros_ec_lpc:
couldn't retrieve IRQ number (-2)
I see a variety of drivers that treat -ENXIO specially, so rather than
fix all of them, let's fix up the API to restore its previous behavior.
I reported this on v2 of this patch:
https://lore.kernel.org/lkml/20190220180538.GA42642@google.com/
but apparently the patch had already been merged before v3 got sent out:
https://lore.kernel.org/lkml/20190221193429.161300-1-egranata@chromium.org/
and the result is that the bug landed and remains unfixed.
I differ from the v3 patch by:
* allowing for ret==0, even though acpi_dev_gpio_irq_get() specifically
documents (and enforces) that 0 is not a valid return value (noted on
the v3 review)
* adding a small comment
Reported-by: Brian Norris <briannorris@chromium.org>
Reported-by: Salvatore Bellizzi <salvatore.bellizzi@linux.seppia.net>
Cc: Enrico Granata <egranata@chromium.org>
Cc: <stable@vger.kernel.org>
Fixes: daaef255dc96 ("driver: platform: Support parsing GpioInt 0 in platform_get_irq()")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Enrico Granata <egranata@google.com>
Link: https://lore.kernel.org/r/20190729204954.25510-1-briannorris@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/platform.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 506a0175a5a7..ec974ba9c0c4 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -157,8 +157,13 @@ int platform_get_irq(struct platform_device *dev, unsigned int num) * the device will only expose one IRQ, and this fallback * allows a common code path across either kind of resource. */ - if (num == 0 && has_acpi_companion(&dev->dev)) - return acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num); + if (num == 0 && has_acpi_companion(&dev->dev)) { + int ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num); + + /* Our callers expect -ENXIO for missing IRQs. */ + if (ret >= 0 || ret == -EPROBE_DEFER) + return ret; + } return -ENXIO; #endif |