iwlwifi: Adjust blink rate to compensate Clock difference

Adjust led blink rate to compensate on a MAC Clock difference on every
HW. Led blink rate analysis showed an average deviation of 0% on 3945,
5% on 4965 HW and 20% on 5000 series and up.
Need to compensate on the led on/off time per HW according to the
deviation to achieve the desired led frequency
The calculation is: (100-averageDeviation)/100 * blinkTime
For code efficiency the calculation will be:
    compensation = (100 - averageDeviation) * 64 / 100
    NewBlinkTime = (compensation * BlinkTime) / 64

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index e50103a..79ea425 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -213,6 +213,9 @@
  * @pa_type: used by 6000 series only to identify the type of Power Amplifier
  * @max_ll_items: max number of OTP blocks
  * @shadow_ram_support: shadow support for OTP memory
+ * @led_compensation: compensate on the led on/off time per HW according
+ *	to the deviation to achieve the desired led frequency.
+ *	The detail algorithm is described in iwl-led.c
  *
  * We enable the driver to be backward compatible wrt API version. The
  * driver specifies which APIs it supports (with @ucode_api_max being the
@@ -255,6 +258,7 @@
 	const bool shadow_ram_support;
 	const bool ht_greenfield_support;
 	const bool broken_powersave;
+	u16 led_compensation;
 };
 
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