target/linux/brcm2708/patches-4.4/0257-clk-bcm2835-divider-value-has-to-be-1-or-more.patch

   1 From 260572944700ab13fa3f7a68a387556220cef277 Mon Sep 17 00:00:00 2001
   2 From: Martin Sperl <kernel@martin.sperl.org>
   3 Date: Mon, 29 Feb 2016 11:39:20 +0000
   4 Subject: [PATCH 257/381] clk: bcm2835: divider value has to be 1 or more
   5
   6 Current clamping of a normal divider allows a value < 1 to be valid.
   7
   8 A divider of < 1 would actually only be possible if we had a PLL...
   9
  10 So this patch clamps the divider to 1.
  11
  12 Fixes: 41691b8862e2 ("clk: bcm2835: Add support for programming the
  13 audio domain clocks")
  14
  15 Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
  16 Signed-off-by: Eric Anholt <eric@anholt.net>
  17 Reviewed-by: Eric Anholt <eric@anholt.net>
  18 (cherry picked from commit 997f16bd5d2e9b3456027f96fcadfe1e2bf12f4e)
  19 ---
  20  drivers/clk/bcm/clk-bcm2835.c | 5 +++--
  21  1 file changed, 3 insertions(+), 2 deletions(-)
  22
  23 --- a/drivers/clk/bcm/clk-bcm2835.c
  24 +++ b/drivers/clk/bcm/clk-bcm2835.c
  25 @@ -1202,8 +1202,9 @@ static u32 bcm2835_clock_choose_div(stru
  26                 div += unused_frac_mask + 1;
  27         div &= ~unused_frac_mask;
  28
  29 -       /* Clamp to the limits. */
  30 -       div = max(div, unused_frac_mask + 1);
  31 +       /* clamp to min divider of 1 */
  32 +       div = max_t(u32, div, 1 << CM_DIV_FRAC_BITS);
  33 +       /* clamp to the highest possible fractional divider */
  34         div = min_t(u32, div, GENMASK(data->int_bits + CM_DIV_FRAC_BITS - 1,
  35                                       CM_DIV_FRAC_BITS - data->frac_bits));
  36