From 9dd5e53d9d2f933039eb2d5e4052afa249f638ba Mon Sep 17 00:00:00 2001
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Date: Mon, 1 Apr 2013 19:09:45 +0100
Subject: [PATCH] extcon: arizona: Retry HPDET identification for high
impedance
Sometimes we can trigger measurements early if contacts are shorted during
a slow insertion. As well as debouncing add further robustness by retrying
if we get a high impedance measurement for headphones as this can indicate
that the headphones were not yet connected.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
drivers/extcon/extcon-arizona.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/extcon/extcon-arizona.c b/drivers/extcon/extcon-arizona.c
index 5344f435f689..c18cf14067c6 100644
--- a/drivers/extcon/extcon-arizona.c
+++ b/drivers/extcon/extcon-arizona.c
@@ -39,6 +39,8 @@
#define ARIZONA_ACCDET_MODE_HPL 1
#define ARIZONA_ACCDET_MODE_HPR 2
+#define ARIZONA_HPDET_MAX 10000
+
#define HPDET_DEBOUNCE 500
struct arizona_extcon_info {
@@ -64,6 +66,7 @@ struct arizona_extcon_info {
bool hpdet_active;
bool hpdet_done;
+ bool hpdet_retried;
int num_hpdet_res;
unsigned int hpdet_res[3];
@@ -112,6 +115,8 @@ static const char *arizona_cable[] = {
NULL,
};
+static void arizona_start_hpdet_acc_id(struct arizona_extcon_info *info);
+
static void arizona_extcon_do_magic(struct arizona_extcon_info *info,
unsigned int magic)
{
@@ -393,7 +398,7 @@ 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) {
dev_dbg(arizona->dev, "Measurement out of range\n");
- return 10000;
+ return ARIZONA_HPDET_MAX;
}
dev_dbg(arizona->dev, "HPDET read %d in range %d\n",
@@ -518,6 +523,16 @@ static int arizona_hpdet_do_id(struct arizona_extcon_info *info, int *reading)
/* Take the headphone impedance for the main report */
*reading = info->hpdet_res[0];
+ /* Sometimes we get false readings due to slow insert */
+ if (*reading >= ARIZONA_HPDET_MAX && !info->hpdet_retried) {
+ dev_dbg(arizona->dev, "Retrying high impedance\n");
+ info->num_hpdet_res = 0;
+ info->hpdet_retried = true;
+ arizona_start_hpdet_acc_id(info);
+ pm_runtime_put(info->dev);
+ return -EAGAIN;
+ }
+
/*
* Either the two grounds measure differently or we
* measure the mic as high impedance.
@@ -953,6 +968,7 @@ static irqreturn_t arizona_jackdet(int irq, void *data)
info->hpdet_res[i] = 0;
info->mic = false;
info->hpdet_done = false;
+ info->hpdet_retried = false;
for (i = 0; i < info->num_micd_ranges; i++)
input_report_key(info->input,