Hi Pavel,
On Sun, Oct 23, 2016 at 12:22:13PM +0200, Pavel Machek wrote:
> Hi!
>
> I tried to update camera code on n900 to v4.9-rc1, and I'm getting
> some divide by zero, that eventually cascades into fcam-dev not
> working.
>
> mul is zero in my testing, resulting in divide by zero.
>
> (Note that this is going from my patched camera-v4.8 tree to
> camera-v4.9 tree.)
>
> Best regards,
> Pavel
>
> diff --git a/drivers/media/i2c/smiapp-pll.c b/drivers/media/i2c/smiapp-pll.c
> index 5ad1edb..e0a6edd 100644
> --- a/drivers/media/i2c/smiapp-pll.c
> +++ b/drivers/media/i2c/smiapp-pll.c
> @@ -16,6 +16,8 @@
> * General Public License for more details.
> */
>
> +#define DEBUG
> +
> #include <linux/device.h>
> #include <linux/gcd.h>
> #include <linux/lcm.h>
> @@ -457,6 +459,10 @@ int smiapp_pll_calculate(struct device *dev,
> i = gcd(pll->pll_op_clk_freq_hz, pll->ext_clk_freq_hz);
> mul = div_u64(pll->pll_op_clk_freq_hz, i);
> div = pll->ext_clk_freq_hz / i;
> + if (!mul) {
Something must be very wrong if you get here.
What are the values of pll->pll_op_clk_freq_hz and pll->ext_clk_freq_hz?
Or... what does dmesg say?
> + dev_err(dev, "forcing mul to 1\n");
> + mul = 1;
> + }
> dev_dbg(dev, "mul %u / div %u\n", mul, div);
>
> min_pre_pll_clk_div =
>
--
Kind regards,
Sakari Ailus
e-mail: sakari.ai...@iki.fi XMPP: sai...@retiisi.org.uk
