-----Original Message----- From: Mark Brown [mailto:broonie@kernel.org] Sent: Thursday, November 06, 2014 1:55 PM To: bardliao@realtek.com
+static int rt5670_runtime_resume(struct device *dev) {
- return 0;
+}
This should be undoing the change done on suspend otherwise we'll be stuck on the internal clock after resuming. Alternatively if something will undo that elsewhere then presumably we don't need to use runtime PM to select the internal clock anyway?
Is it okay to restore default sysclock setting is runtime_resume ops?
The codec sysclk source is MCLK (PLL is powered down) after boot by default. We can also apply this when runtime resuming.
On Intel CherryTrail/Braswell platform, the BIOS will always restore MCLK when the codec resumes from D3 to D0. So it's safe to use MCLK as source for codec sysclk in runtime_resume ops. And later hw_params ops can further configure sysclk source and PLL for active audio streaming.
Thanks Mengdong