power: qcom_smbb: Make an extcon for usb cable detection

On these PMICs the usb cable connection/disconnection is
indicated by the usb-valid interrupt being high or low
respectively. Let's make an extcon for that, so we can notify usb
drivers of the cable state.

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

2 files changed, 22 insertions, 0 deletions

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 421770ddafa3..6bff735c632d 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -393,6 +393,7 @@ config CHARGER_QCOM_SMBB
         tristate "Qualcomm Switch-Mode Battery Charger and Boost"
         depends on MFD_SPMI_PMIC || COMPILE_TEST
         depends on OF
+        depends on EXTCON
         help
           Say Y to include support for the Switch-Mode Battery Charger and
           Boost (SMBB) hardware found in Qualcomm PM8941 PMICs.  The charger
diff --git a/drivers/power/qcom_smbb.c b/drivers/power/qcom_smbb.c
index 5eb1e9e543e2..b5896ba2a602 100644
--- a/drivers/power/qcom_smbb.c
+++ b/drivers/power/qcom_smbb.c
@@ -34,6 +34,7 @@
 #include <linux/power_supply.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
+#include <linux/extcon.h>
 
 #define SMBB_CHG_VMAX           0x040
 #define SMBB_CHG_VSAFE          0x041
@@ -111,6 +112,7 @@ struct smbb_charger {
         unsigned int revision;
         unsigned int addr;
         struct device *dev;
+        struct extcon_dev *edev;
 
         bool dc_disabled;
         bool jeita_ext_temp;
@@ -125,6 +127,11 @@ struct smbb_charger {
         struct regmap *regmap;
 };
 
+static const unsigned int smbb_usb_extcon_cable[] = {
+        EXTCON_USB,
+        EXTCON_NONE,
+};
+
 static int smbb_vbat_weak_fn(unsigned int index)
 {
         return 2100000 + index * 100000;
@@ -371,6 +378,8 @@ static irqreturn_t smbb_usb_valid_handler(int irq, void *_data)
         struct smbb_charger *chg = _data;
 
         smbb_set_line_flag(chg, irq, STATUS_USBIN_VALID);
+        extcon_set_cable_state_(chg->edev, EXTCON_USB,
+                                chg->status & STATUS_USBIN_VALID);
         power_supply_changed(chg->usb_psy);
 
         return IRQ_HANDLED;
@@ -849,6 +858,18 @@ static int smbb_charger_probe(struct platform_device *pdev)
                 return PTR_ERR(chg->usb_psy);
         }
 
+        chg->edev = devm_extcon_dev_allocate(&pdev->dev, smbb_usb_extcon_cable);
+        if (IS_ERR(chg->edev)) {
+                dev_err(&pdev->dev, "failed to allocate extcon device\n");
+                return -ENOMEM;
+        }
+
+        rc = devm_extcon_dev_register(&pdev->dev, chg->edev);
+        if (rc < 0) {
+                dev_err(&pdev->dev, "failed to register extcon device\n");
+                return rc;
+        }
+
         if (!chg->dc_disabled) {
                 dc_cfg.drv_data = chg;
                 dc_cfg.supplied_to = smbb_bif;