If several parallel bq24735 chargers have their ac-detect gpios wired
together (or if only one of the parallel bq24735 chargers have its
ac-detect pin wired to a gpio, and the others are assumed to react the
same), then all driver instances need to check the same gpio. But the
gpio subsystem does not allow sharing gpios, so handle that locally.

However, only do this for the polling case, sharing is not supported if
the ac detection is handled with interrupts.

Signed-off-by: Peter Rosin <redacted>
---
 drivers/power/supply/bq24735-charger.c | 101 +++++++++++++++++++++++++++++----
 1 file changed, 90 insertions(+), 11 deletions(-)

diff --git a/drivers/power/supply/bq24735-charger.c b/drivers/power/supply/bq24735-charger.c
index 3765806d5d46..3b21a064a9a7 100644
--- a/drivers/power/supply/bq24735-charger.c
+++ b/drivers/power/supply/bq24735-charger.c

@@ -25,6 +25,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_gpio.h>
 #include <linux/gpio/consumer.h>
 #include <linux/power_supply.h>
 #include <linux/slab.h>

@@ -43,12 +44,24 @@
 #define BQ24735_MANUFACTURER_ID		0xfe
 #define BQ24735_DEVICE_ID		0xff
 
+struct bq24735;
+
+struct bq24735_shared {
+	struct list_head		list;
+	struct bq24735			*owner;
+	struct gpio_desc		*status_gpio;
+};
+
+static struct mutex shared_lock;