On 3/29/2019 2:12 PM, Geert Uytterhoeven wrote:
Simple string comparisons are cheaper than DT lookups, as the latter
involve taking a spinlock and traversing properties.
Hence optimize quirk checks by postponing DT lookups after string
comparisons.
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Looks good to me.
Reviewed-by: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>
Cheers,
-Mukesh
---
drivers/gpio/gpiolib-of.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 6a3ec575a404ed9f..3a6bb53d89dfed32 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -86,9 +86,9 @@ static void of_gpio_flags_quirks(struct device_node *np,
if (IS_ENABLED(CONFIG_REGULATOR) &&
(of_device_is_compatible(np, "regulator-fixed") ||
of_device_is_compatible(np, "reg-fixed-voltage") ||
- (of_device_is_compatible(np, "regulator-gpio") &&
- !(strcmp(propname, "enable-gpio") &&
- strcmp(propname, "enable-gpios"))))) {
+ (!(strcmp(propname, "enable-gpio") &&
+ strcmp(propname, "enable-gpios")) &&
+ of_device_is_compatible(np, "regulator-gpio")))) {
/*
* The regulator GPIO handles are specified such that the
* presence or absence of "enable-active-high" solely controls
@@ -119,9 +119,8 @@ static void of_gpio_flags_quirks(struct device_node *np,
* property named "cs-gpios" we need to inspect the child node
* to determine if the flags should have inverted semantics.
*/
- if (IS_ENABLED(CONFIG_SPI_MASTER) &&
- of_property_read_bool(np, "cs-gpios") &&
- !strcmp(propname, "cs-gpios")) {
+ if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
+ of_property_read_bool(np, "cs-gpios")) {
struct device_node *child;
u32 cs;
int ret;
