On Tuesday 29 May 2018 11:36 PM, Wolfram Sang wrote:
Our I2C driver is based on the interrupt. So we have converted the
suspend/resume to suspend_noirq and reseume_noirq so that we will not allow the
transfer when system interrupt disabled in downstream.
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume)
In shutdown path, where interrupt disabled and still need i2c, we use the
bit-bang method via GPIO for i2c transfer.
In the current upstream kernel suspend/resume can't be simply moved to the
'noirq' stage because resume invokes tegra_i2c_init() which uses runtime PM and
that doesn't work with the IRQ's being disabled. But things do not work even
with the tegra_i2c_init() changed to work with the disabled IRQ's, like I wrote
above the I2C transfer fails (due to timeout) and a "fix" for that failure was
to remove reset_control_assert/deassert from the tegra_i2c_init(). So I'd go for
a complete suspend/resume removal for now as it is causes problem.
Laxman, are you convinced or do you have still objections?
Fine with me. Please add my Ack
Acked-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>
