Messages in this thread Patch in this message | | | From | "Rafael J. Wysocki" <> | Subject | [PATCH 1/2] gpio / ACPI: Avoid unnecessary checks in __gpiod_get_index() | Date | Tue, 10 Mar 2015 23:08:57 +0100 |
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From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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> --- drivers/gpio/gpiolib.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)
Index: linux-pm/drivers/gpio/gpiolib.c =================================================================== --- linux-pm.orig/drivers/gpio/gpiolib.c +++ linux-pm/drivers/gpio/gpiolib.c @@ -1865,13 +1865,15 @@ struct gpio_desc *__must_check __gpiod_g 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); + } } /*
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