diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-03-11 01:08:57 +0300 |
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committer | Linus Walleij <linus.walleij@linaro.org> | 2015-03-19 11:46:04 +0300 |
commit | 4d8440b93ce8a8544199804dbcf997b2ab3dad11 (patch) | |
tree | 77458cfa065d39cc50c3be2801463d830fd07d36 /drivers/gpio/gpiolib.c | |
parent | 964cb341882f920a1a1043864178f22def3193e4 (diff) | |
download | linux-4d8440b93ce8a8544199804dbcf997b2ab3dad11.tar.xz |
gpio / ACPI: Avoid unnecessary checks in __gpiod_get_index()
If dev is NULL in __gpiod_get_index() and both ACPI and OF are
enabled, it will be checked twice before the code decides to give
up with DT/ACPI lookup, so avoid that.
Also use the observation that ACPI_COMPANION() is much more efficient
than ACPI_HANDLE(), because the latter uses the former and carries out
a check and a pointer dereference on top of it, so replace the
ACPI_HANDLE() check with an ACPI_COMPANION() one which does not
require the additional IS_ENABLED(CONFIG_ACPI) check too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 3d5b85a7dcdf..59eaa23767d8 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1971,13 +1971,15 @@ struct gpio_desc *__must_check __gpiod_get_index(struct device *dev, dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); - /* Using device tree? */ - if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { - dev_dbg(dev, "using device tree for GPIO lookup\n"); - desc = of_find_gpio(dev, con_id, idx, &lookupflags); - } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { - dev_dbg(dev, "using ACPI for GPIO lookup\n"); - desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); + if (dev) { + /* Using device tree? */ + if (IS_ENABLED(CONFIG_OF) && dev->of_node) { + dev_dbg(dev, "using device tree for GPIO lookup\n"); + desc = of_find_gpio(dev, con_id, idx, &lookupflags); + } else if (ACPI_COMPANION(dev)) { + dev_dbg(dev, "using ACPI for GPIO lookup\n"); + desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); + } } /* |