On Mon, 7 Nov 2016 21:05:05 +0100 Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: > 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 <wens@xxxxxxxx> wrote: > > > > > On Fri, Oct 21, 2016 at 4:36 PM, Jean-Francois Moine <moinejf@xxxxxxx> wrote: > > > > This patch adds I2S support to sun8i SoCs as the A83T and H3. > > > > > > > > Signed-off-by: Jean-Francois Moine <moinejf@xxxxxxx> > > > > --- > > > > 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. #define field_relaxed(addr, mask, val) \ writel_relaxed((readl_relaxed(addr) & mask) | val, addr) > > 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) Is it time to remove this useless code? > > 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? When the I/O registers are in memory (that's the case), you may access them (read and write) thru /dev/mem. Also, is a register access trace really needed in this driver? The pain is to define the regmap_config (which registers can be read/write/volatile and which can be the values the u-boot let us in the registers at startup time), and the lot of code which is run instead of simple load/store machine instructions. -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
