[PATCH 3/4] extcon: arizona: Update manual headphone detection calculation

From: Charles Keepax
Date: Thu May 29 2014 - 11:36:06 EST


The higher levels of impedance have a higher minimum value than the
first level. As the same value was used for all levels, higher impedances
were reported with a very low level of accuracy. This patch applies the
approriate lower threshold for each level.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---
drivers/extcon/extcon-arizona.c | 13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/extcon/extcon-arizona.c b/drivers/extcon/extcon-arizona.c
index f2c36b1..c1c8647 100644
--- a/drivers/extcon/extcon-arizona.c
+++ b/drivers/extcon/extcon-arizona.c
@@ -329,12 +329,13 @@ static void arizona_stop_mic(struct arizona_extcon_info *info)
}

static struct {
+ unsigned int threshold;
unsigned int factor_a;
unsigned int factor_b;
} arizona_hpdet_b_ranges[] = {
- { 5528, 362464 },
- { 11084, 6186851 },
- { 11065, 65460395 },
+ { 100, 5528, 362464 },
+ { 169, 11084, 6186851 },
+ { 169, 11065, 65460395 },
};

static struct {
@@ -391,7 +392,8 @@ static int arizona_hpdet_read(struct arizona_extcon_info *info)
>> ARIZONA_HP_IMPEDANCE_RANGE_SHIFT;

if (range < ARRAY_SIZE(arizona_hpdet_b_ranges) - 1 &&
- (val < 100 || val >= 0x3fb)) {
+ (val < arizona_hpdet_b_ranges[range].threshold ||
+ val >= 0x3fb)) {
range++;
dev_dbg(arizona->dev, "Moving to HPDET range %d\n",
range);
@@ -404,7 +406,8 @@ static int arizona_hpdet_read(struct arizona_extcon_info *info)
}

/* If we go out of range report top of range */
- if (val < 100 || val >= 0x3fb) {
+ if (val < arizona_hpdet_b_ranges[range].threshold ||
+ val >= 0x3fb) {
dev_dbg(arizona->dev, "Measurement out of range\n");
return ARIZONA_HPDET_MAX;
}
--
1.7.2.5

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