Re: [RESEND PATCH 1/2] spi: rockchip: Convert to late and early system PM callbacks

From: jeffy
Date: Fri Oct 13 2017 - 14:26:01 EST


On 10/14/2017 02:19 AM, jeffy wrote:


it looks like the suspend sequence depends on the dt node sequence, and
we are putting display-subsystem dt node above spi dt node, so it would
be earlier in the device list, then got suspended later than spi device.

the pwm backlight and cros_ec_spi pwm are very interesting, not only
about suspend dependency... if we unbind cros_ec_spi pwm, the pwm
backlight would still hold a reference to it, and crash the kernel later.

or maybe we should move device_pm_add() from device_add() to driver_bound()?