[PATCH V2 2/2] power: twl4030_charger: attempt to power off in case of critical events

[Nishanth Menon]

Attempt to power off in case of critical events such as battery removal,
over voltage events.

There is no guarentee that we'd be in a safe scenario here, but the very
least we can try to do is to power off the device to prevent damage to
the system instead of just printing a message and hoping for the best.

NOTE: twl4030 should attempt some form of recovery, but just depending
on that is never a safe alternative.

Signed-off-by: Nishanth Menon <nm at ti.com>
---
new patch. original attempt was: https://patchwork.kernel.org/patch/4002371/

NOTE: we dont have poweroff support yet enabled on LDP, but it just needs
relevant dts entry.

 drivers/power/twl4030_charger.c |   26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/power/twl4030_charger.c b/drivers/power/twl4030_charger.c
index 2598c58..ed0dbd2 100644
--- a/drivers/power/twl4030_charger.c
+++ b/drivers/power/twl4030_charger.c
@@ -22,6 +22,7 @@
 #include <linux/power_supply.h>
 #include <linux/notifier.h>
 #include <linux/usb/otg.h>
+#include <linux/reboot.h>
 #include <linux/regulator/machine.h>
 
 #define TWL4030_BCIMSTATEC	0x02
@@ -332,6 +333,7 @@ static irqreturn_t twl4030_bci_interrupt(int irq, void *arg)
 	struct twl4030_bci *bci = arg;
 	u8 irqs1, irqs2;
 	int ret;
+	bool power_off = false;
 
 	ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs1,
 			      TWL4030_INTERRUPTS_BCIISR1A);
@@ -352,20 +354,34 @@ static irqreturn_t twl4030_bci_interrupt(int irq, void *arg)
 	}
 
 	/* various monitoring events, for now we just log them here */
-	if (irqs1 & (TWL4030_TBATOR2 | TWL4030_TBATOR1))
+	if (irqs1 & (TWL4030_TBATOR2 | TWL4030_TBATOR1)) {
 		dev_warn(bci->dev, "battery temperature out of range\n");
+		power_off = true;
+	}
 
-	if (irqs1 & TWL4030_BATSTS)
+	if (irqs1 & TWL4030_BATSTS) {
 		dev_crit(bci->dev, "battery disconnected\n");
+		power_off = true;
+	}
 
-	if (irqs2 & TWL4030_VBATOV)
+	if (irqs2 & TWL4030_VBATOV) {
 		dev_crit(bci->dev, "VBAT overvoltage\n");
+		power_off = true;
+	}
 
-	if (irqs2 & TWL4030_VBUSOV)
+	if (irqs2 & TWL4030_VBUSOV) {
 		dev_crit(bci->dev, "VBUS overvoltage\n");
+		power_off = true;
+	}
 
-	if (irqs2 & TWL4030_ACCHGOV)
+	if (irqs2 & TWL4030_ACCHGOV) {
 		dev_crit(bci->dev, "Ac charger overvoltage\n");
+		power_off = true;
+	}
+
+	/* Try to shutdown the system */
+	if (power_off)
+		orderly_poweroff(true);
 
 	return IRQ_HANDLED;
 }
-- 
1.7.9.5