power: supply: use sysfs_emit() instead of sprintf() for sysfs show()

As documented in Documentation/filesystems/sysfs.rst the sysfs show()
function should use sysfs_emit() or sysfs_emit_at() to format the
userspace return value. This replaces all sysfs related instances of
sprintf() with sysfs_emit() in the power-supply subsystem.

Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
[Drop sysfs_emit changes done for code not related to sysfs show
and reword commit message]
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: mp2629_charger: use platform_get_irq()

Calling platform_get_irq_optional() doesn't make sense if you then bail out
on any error it returns. Switch to calling platform_get_irq() instead and
remove dev_err() call as platform_get_irq() already curses loudly on error.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: supply: Add support for mps mp2629 battery charger

The mp2629 provides switching-mode battery charge management for
single-cell Li-ion or Li-polymer battery. Driver supports the
access/control input source and battery charging parameters.

Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>