On Mon, Jun 28, 2010 at 08:44:46AM +0200, Raffaele Recalcati wrote:
From: Raffaele Recalcati raffaele.recalcati@bticino.it
It's still very hard to understand what this patch is supposed to do. As previously mentioned this would probably be a lot clearer if you split this into multiple patches, for example one adding support for the fast clock mode, one adding support for selecting the pin used for any external clock and then further patches with any other changes.
I strongly suggest looking at the commit messages for other patches in the kernel and trying to follow a similar style.
Added audio playback support with [frame sync master - clock master] mode and with [frame sync master - clock slave].
What are these modes - which clock are you talking about?
i2s_fast_clock switch can be used to have better approximate or symmetric waveforms.
Why would someone choose not to use this?
clk_input_pin board info can be used to select it depending on hw connections
3. We haven't changed the evmdm365 support (due also to CPLD that doesn't help to understand) We don't know in this mode if audio stereo works on evmdm365. Probably it does.
This is what makes me unsure if you're trying to add new modes or not - if you're adding new modes then I'd expect that existing boards would be unaffected with any changes to use the new feature being easily seperable.
- /*
* This define works when both clock and FS are output for the cpu* and makes clock very fast (FS is not simmetrical, but sampling
symmetrical.
* frequency is better approximated*/- int i2s_fast_clock;
Is this a bool?
- /* To be used when cpu gets clock from extenal pin */
- int clk_input_pin;
How would one use this?
case SND_SOC_DAIFMT_CBM_CFS:
/* McBSP CLKR pin is the input for the Sample Rate Generator.* McBSP FSR and FSX are driven by the Sample Rate Generator. */pcr = DAVINCI_MCBSP_PCR_SCLKME |DAVINCI_MCBSP_PCR_FSXM |DAVINCI_MCBSP_PCR_FSRM;
pcr = DAVINCI_MCBSP_PCR_FSRM | DAVINCI_MCBSP_PCR_FSXM;if (dev->clk_input_pin == MCBSP_CLKS)pcr |= DAVINCI_MCBSP_PCR_CLKXM |DAVINCI_MCBSP_PCR_CLKRM;else/** McBSP CLKR pin is the input for the Sample Rate* Generator.* McBSP FSR and FSX are driven by the Sample Rate* Generator.*/pcr |= DAVINCI_MCBSP_PCR_SCLKME;
This looks like you need a switch statement for the clock selection.
+static int davinci_i2s_dai_set_clkdiv(struct snd_soc_dai *cpu_dai,
int div_id, int div)+{
- struct davinci_mcbsp_dev *dev = cpu_dai->private_data;
- int srgr;
- dev->clk_div = div;
- return 0;
+}
I would add a clock ID here in case someone wants to configure another clock in the patch.
- if (master == SND_SOC_DAIFMT_CBS_CFS) {
Use a switch staetment for this too.
clk = clk_get(NULL, "pll1_sysclk6");
You're doing a clk_get() every time you go through here but never freeing it - it would seem better to just do the clk_get() at startup. I'd also expect this to be doing a clk_get() using the struct device for the DAI so that the driver can function even if the clock tree for a new SoC is different.
if (clk)freq = clk_get_rate(clk);
clk_get() returns an error pointer on error, not NULL, and...
freq = 122000000; /* FIXME ask to Texas */
...this presumably ought to be in an else clause (or perhaps just not using this clocking at all if you can't find the clock?).
- } else if (master == SND_SOC_DAIFMT_CBM_CFS) {
/* Clock given on CLKS */
What if the user selected a different clock source?
if (master == SND_SOC_DAIFMT_CBS_CFS ||master == SND_SOC_DAIFMT_CBS_CFM) {
Again, switch statement.
- if (master == SND_SOC_DAIFMT_CBS_CFS ||
master == SND_SOC_DAIFMT_CBS_CFM) {
Here too.