leds: Change led_trigger_blink[_oneshot]() delay parameters to pass-by-value

led_blink_set[_oneshot]()'s delay_on and delay_off function parameters
are pass by reference, so that hw-blink implementations can report
back the actual achieved delays when the values have been rounded
to something the hw supports.

This is really only interesting for the sysfs API / the timer trigger.
Other triggers don't really care about this and none of the callers of
led_trigger_blink[_oneshot]() do anything with the returned delay values.

Change the led_trigger_blink[_oneshot]() delay parameters to pass-by-value,
there are 2 reasons for this:

1. led_cdev->blink_set() may sleep, while led_trigger_blink() may not.
So on hw where led_cdev->blink_set() sleeps the call needs to be deferred
to a workqueue, in which case the actual achieved delays are unknown
(this is a preparation patch for the deferring).

2. Since the callers don't care about the actual achieved delays, allowing
callers to directly pass a value leads to simpler code for most callers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Tested-by: Yauhen Kharuzhy <jekhor@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230510162234.291439-2-hdegoede@redhat.com
Signed-off-by: Lee Jones <lee@kernel.org>

1 files changed, 1 insertions, 3 deletions

diff --git a/drivers/usb/common/led.c b/drivers/usb/common/led.c
index 0865dd44a80a..1de18d90b134 100644
--- a/drivers/usb/common/led.c
+++ b/drivers/usb/common/led.c
@@ -14,8 +14,6 @@
 
 #define BLINK_DELAY 30
 
-static unsigned long usb_blink_delay = BLINK_DELAY;
-
 DEFINE_LED_TRIGGER(ledtrig_usb_gadget);
 DEFINE_LED_TRIGGER(ledtrig_usb_host);
 
@@ -32,7 +30,7 @@ void usb_led_activity(enum usb_led_event ev)
 		break;
 	}
 	/* led_trigger_blink_oneshot() handles trig == NULL gracefully */
-	led_trigger_blink_oneshot(trig, &usb_blink_delay, &usb_blink_delay, 0);
+	led_trigger_blink_oneshot(trig, BLINK_DELAY, BLINK_DELAY, 0);
 }
 EXPORT_SYMBOL_GPL(usb_led_activity);