Thread (3 messages) flat view 3 messages, 2 authors, 2016-11-08

[linux-sunxi] [PATCH v5 4/7] ASoC: sunxi: Add sun8i I2S driver

From: Maxime Ripard <hidden>
Date: 2016-11-07 20:05:05
Also in: alsa-devel, dri-devel, linux-devicetree

Hi,

On Sun, Nov 06, 2016 at 07:02:48PM +0100, Jean-Francois Moine wrote:
On Sun, 23 Oct 2016 09:33:16 +0800
Chen-Yu Tsai [off-list ref] wrote:
quoted
On Fri, Oct 21, 2016 at 4:36 PM, Jean-Francois Moine [off-list ref] wrote:
quoted
This patch adds I2S support to sun8i SoCs as the A83T and H3.

Signed-off-by: Jean-Francois Moine <redacted>
---
Note: This driver is closed to the sun4i-i2s except that:
- it handles the H3
If it's close to sun4i-i2s, you should probably rework that one to support
the newer SoCs.
I started to add the H3 into the sun4i-i2s, but I am blocked with
regmap.
Many H3 registers are common with the A10, but some of them have more
or less fields, the fields may be at different offsets. And, finally,
some registers are completely different.
This would not raise any problem, except with regmap which is really
painful.
That's weird, because regmap's regmap_field should make that much
easier.
As I may understood, regmap is used to simplify suspend/resume, but, is
it useful to save the I2S register on suspend?
Practically, I am streaming some tune on my device. I suspend it for
any reason. The next morning, I resume it. Are you sure I want to
continue to hear the end of the tune?

I better think that streaming should be simply stopped on suspend.
You're mistaken. The code in there is for *runtime* suspend, ie when
the device is no longer used, so that case shouldn't even happen at
all.

(And real suspend isn't supported anyway)
Then, there is no need to save the playing registers, and, here I am,
there is no need to use regmap.

May I go this way?
No, please don't. regmap is also providing very useful features, such
as access to all the registers through debugfs, or tracing. What
exactly feels painful to you?

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20161107/a27a59e7/attachment.sig>
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help