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>
This commit is contained in:
Wey-Yi Guy
2009-09-11 10:38:14 -07:00
committed by John W. Linville
parent c812ee2485
commit f2d0d0e2ba
7 changed files with 50 additions and 2 deletions

View File

@@ -78,6 +78,29 @@ static const struct {
#define IWL_MAX_BLINK_TBL (ARRAY_SIZE(blink_tbl) - 1) /* exclude SOLID_ON */
#define IWL_SOLID_BLINK_IDX (ARRAY_SIZE(blink_tbl) - 1)
/*
* 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
*/
static inline u8 iwl_blink_compensation(struct iwl_priv *priv,
u8 time, u16 compensation)
{
if (!compensation) {
IWL_ERR(priv, "undefined blink compensation: "
"use pre-defined blinking time\n");
return time;
}
return (u8)((time * compensation) >> 6);
}
/* [0-256] -> [0..8] FIXME: we need [0..10] */
static inline int iwl_brightness_to_idx(enum led_brightness brightness)
{
@@ -114,8 +137,14 @@ static int iwl_led_pattern(struct iwl_priv *priv, int led_id,
BUG_ON(idx > IWL_MAX_BLINK_TBL);
led_cmd.on = blink_tbl[idx].on_time;
led_cmd.off = blink_tbl[idx].off_time;
IWL_DEBUG_LED(priv, "Led blink time compensation= %u\n",
priv->cfg->led_compensation);
led_cmd.on =
iwl_blink_compensation(priv, blink_tbl[idx].on_time,
priv->cfg->led_compensation);
led_cmd.off =
iwl_blink_compensation(priv, blink_tbl[idx].off_time,
priv->cfg->led_compensation);
return iwl_send_led_cmd(priv, &led_cmd);
}