On Fri, Jun 13, 2014 at 11:00:01AM +0200, Takashi Iwai wrote:
At Thu, 12 Jun 2014 22:24:55 -0500, Timur Tabi wrote:
On Thu, Dec 12, 2013 at 4:44 AM, Nicolin Chen Guangyu.Chen@freescale.com wrote:
+static int fsl_ssi_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
int clk_id, unsigned int freq, int dir)+{
struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai);struct ccsr_ssi __iomem *ssi = ssi_private->ssi;int synchronous = ssi_private->cpu_dai_drv.symmetric_rates, ret;u32 pm = 999, div2, psr, stccr, mask, afreq, factor, i;unsigned long flags, clkrate, baudrate, tmprate;u64 sub, savesub = 100000;/* Don't apply it to any non-baudclk circumstance */if (IS_ERR(ssi_private->baudclk))return -EINVAL;/* It should be already enough to divide clock by setting pm alone */psr = 0;div2 = 0;factor = (div2 + 1) * (7 * psr + 1) * 2;for (i = 0; i < 255; i++) {/* The bclk rate must be smaller than 1/5 sysclk rate */if (factor * (i + 1) < 5)continue;tmprate = freq * factor * (i + 2);clkrate = clk_round_rate(ssi_private->baudclk, tmprate);do_div(clkrate, factor);This do_div() call causes this warning on PowerPC:
CC sound/soc/fsl/fsl_ssi.o sound/soc/fsl/fsl_ssi.c: In function 'fsl_ssi_set_bclk': sound/soc/fsl/fsl_ssi.c:593:3: warning: comparison of distinct pointer types lacks a cast sound/soc/fsl/fsl_ssi.c:593:3: warning: right shift count >= width of type sound/soc/fsl/fsl_ssi.c:593:3: warning: passing argument 1 of '__div64_32' from incompatible pointer type include/asm-generic/div64.h:35:17: note: expected 'uint64_t *' but argument is of type 'long unsigned int *'
The comments in do_div() say that clkrate should be 64-bits. Changing clkrate to a u64 does fix this problem, but I'm wondering if anyone else has seen this. This code has been around for months.
Using do_div() for unsigned long makes no sense. And, you *must* pass uint64_t there as an argument, since it's no inline function and there is no implicit conversion in the generic code.
In short, use the normal division operator instead: clkrate /= factor;
Yes. I forgot why I used do_div() for clkrate at the first place but it's definitely a mistake here.
Sorry, Nicolin
Takashi