[PATCH 20/57] power: Adds support for legacy USB chargers

From: mathieu . poirier
Date: Tue Sep 25 2012 - 12:22:31 EST


From: Marcus Cooper <marcus.xm.cooper@xxxxxxxxxxxxxx>

A Legacy USB charger should be handled directly by the charger
driver.

Signed-off-by: Marcus Cooper <marcus.xm.cooper@xxxxxxxxxxxxxx>
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Reviewed-by: Karl KOMIEROWSKI <karl.komierowski@xxxxxxxxxxxxxx>
Reviewed-by: Jonas ABERG <jonas.aberg@xxxxxxxxxxxxxx>
---
drivers/power/ab8500_charger.c | 66 ++++++++++++++++++++++++++++++++++-----
1 files changed, 57 insertions(+), 9 deletions(-)

diff --git a/drivers/power/ab8500_charger.c b/drivers/power/ab8500_charger.c
index 4155feb..7cd4165 100644
--- a/drivers/power/ab8500_charger.c
+++ b/drivers/power/ab8500_charger.c
@@ -85,6 +85,9 @@
/* Step up/down delay in us */
#define STEP_UDELAY 1000

+/* Wait for enumeration before charging in ms */
+#define WAIT_FOR_USB_ENUMERATION (5 * 1000)
+
#define CHARGER_STATUS_POLL 10 /* in ms */

/* UsbLineStatus register - usb types */
@@ -198,6 +201,7 @@ struct ab8500_charger_usb_state {
* charger is enabled
* @vbat Battery voltage
* @old_vbat Previously measured battery voltage
+ * @usb_device_is_unrecognised USB device is unrecognised by the hardware
* @autopower Indicate if we should have automatic pwron after pwrloss
* @parent: Pointer to the struct ab8500
* @gpadc: Pointer to the struct gpadc
@@ -216,6 +220,7 @@ struct ab8500_charger_usb_state {
* @check_usbchgnotok_work: Work for checking USB charger not ok status
* @kick_wd_work: Work for kicking the charger watchdog in case
* of ABB rev 1.* due to the watchog logic bug
+ * @attach_work: Work for checking the usb enumeration
* @ac_charger_attached_work: Work for checking if AC charger is still
* connected
* @usb_charger_attached_work: Work for checking if USB charger is still
@@ -239,6 +244,7 @@ struct ab8500_charger {
bool vddadc_en_usb;
int vbat;
int old_vbat;
+ bool usb_device_is_unrecognised;
bool autopower;
struct ab8500 *parent;
struct ab8500_gpadc *gpadc;
@@ -256,6 +262,7 @@ struct ab8500_charger {
struct delayed_work check_hw_failure_work;
struct delayed_work check_usbchgnotok_work;
struct delayed_work kick_wd_work;
+ struct delayed_work attach_work;
struct delayed_work ac_charger_attached_work;
struct delayed_work usb_charger_attached_work;
struct work_struct ac_work;
@@ -588,6 +595,8 @@ static int ab8500_charger_max_usb_curr(struct ab8500_charger *di,
{
int ret = 0;

+ di->usb_device_is_unrecognised = false;
+
switch (link_status) {
case USB_STAT_STD_HOST_NC:
case USB_STAT_STD_HOST_C_NS:
@@ -633,9 +642,15 @@ static int ab8500_charger_max_usb_curr(struct ab8500_charger *di,
dev_dbg(di->dev, "USB Type - 0x%02x MaxCurr: %d", link_status,
di->max_usb_in_curr);
break;
+ case USB_STAT_NOT_CONFIGURED:
+ if (di->vbus_detected) {
+ di->usb_device_is_unrecognised = true;
+ dev_dbg(di->dev, "USB Type - Legacy charger.\n");
+ di->max_usb_in_curr = USB_CH_IP_CUR_LVL_1P5;
+ break;
+ }
case USB_STAT_HM_IDGND:
case USB_STAT_NOT_VALID_LINK:
- case USB_STAT_NOT_CONFIGURED:
dev_err(di->dev, "USB Type - Charging not allowed\n");
di->max_usb_in_curr = USB_CH_IP_CUR_LVL_0P05;
ret = -ENXIO;
@@ -1899,6 +1914,30 @@ static void ab8500_charger_detect_usb_type_work(struct work_struct *work)
}

/**
+ * ab8500_charger_usb_link_attach_work() - delayd work to detect USB type
+ * @work: pointer to the work_struct structure
+ *
+ * Detect the type of USB plugged
+ */
+static void ab8500_charger_usb_link_attach_work(struct work_struct *work)
+{
+ int ret;
+
+ struct ab8500_charger *di = container_of(work,
+ struct ab8500_charger, attach_work.work);
+
+ /* Update maximum input current if USB enumeration is not detected */
+ if (!di->usb.charger_online) {
+ ret = ab8500_charger_set_vbus_in_curr(di, di->max_usb_in_curr);
+ if (ret)
+ return;
+ }
+
+ ab8500_charger_set_usb_connected(di, true);
+ ab8500_power_supply_changed(di, &di->usb_chg.psy);
+}
+
+/**
* ab8500_charger_usb_link_status_work() - work to detect USB type
* @work: pointer to the work_struct structure
*
@@ -1928,14 +1967,20 @@ static void ab8500_charger_usb_link_status_work(struct work_struct *work)
di->vbus_detected = 1;
ret = ab8500_charger_read_usb_type(di);
if (!ret) {
- /* Update maximum input current */
- ret = ab8500_charger_set_vbus_in_curr(di,
- di->max_usb_in_curr);
- if (ret)
- return;
-
- ab8500_charger_set_usb_connected(di, true);
- ab8500_power_supply_changed(di, &di->usb_chg.psy);
+ if (di->usb_device_is_unrecognised) {
+ dev_dbg(di->dev,
+ "Potential Legacy Charger device. "
+ "Delay work for %d msec for USB enum "
+ "to finish",
+ WAIT_FOR_USB_ENUMERATION);
+ queue_delayed_work(di->charger_wq,
+ &di->attach_work,
+ msecs_to_jiffies
+ (WAIT_FOR_USB_ENUMERATION));
+ } else {
+ queue_delayed_work(di->charger_wq,
+ &di->attach_work, 0);
+ }
} else if (ret == -ENXIO) {
/* No valid charger type detected */
ab8500_charger_set_usb_connected(di, false);
@@ -2886,6 +2931,9 @@ static int __devinit ab8500_charger_probe(struct platform_device *pdev)
INIT_DELAYED_WORK_DEFERRABLE(&di->kick_wd_work,
ab8500_charger_kick_watchdog_work);

+ INIT_DELAYED_WORK(&di->attach_work,
+ ab8500_charger_usb_link_attach_work);
+
INIT_DELAYED_WORK_DEFERRABLE(&di->check_vbat_work,
ab8500_charger_check_vbat_work);

--
1.7.5.4

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