[PATCH] clk: divider: fix incorrect usage of container_of

Sylvain Lemieux slemieux.tyco at gmail.com
Fri Dec 22 05:51:25 PST 2017


For lpc32xx:
Acked-by: Sylvain Lemieux <slemieux.tyco at gmail.com>

On Fri, Dec 22, 2017 at 5:34 AM, Alexandre Belloni
<alexandre.belloni at free-electrons.com> wrote:
> On 21/12/2017 at 17:30:54 +0100, Jerome Brunet wrote:
>> divider_recalc_rate() is an helper function used by clock divider of
>> different types, so the structure containing the 'hw' pointer is not
>> always a 'struct clk_divider'
>>
>> At the following line:
>> > div = _get_div(table, val, flags, divider->width);
>>
>> in several cases, the value of 'divider->width' is garbage as the actual
>> structure behind this memory is not a 'struct clk_divider'
>>
>> Fortunately, this width value is used by _get_val() only when
>> CLK_DIVIDER_MAX_AT_ZERO flag is set. This has never been the case so
>> far when the structure is not a 'struct clk_divider'. This is probably
>> why we did not notice this bug before
>>
>> Fixes: afe76c8fd030 ("clk: allow a clk divider with max divisor when zero")
>> Signed-off-by: Jerome Brunet <jbrunet at baylibre.com>
>
> For RTC:
> Acked-by: Alexandre Belloni <alexandre.belloni at free-electrons.com>
>
>> ---
>> Hi Stephen, Mike,
>>
>> In addition to clock, this patch also touch the rtc and drm directories.
>> As it is changing the API of the helper function, I have this fix in a
>> single commit to avoid breaking bisect.
>>
>> Please let me know if you prefer to do differently.
>>
>> Cheers
>> Jerome
>>
>> drivers/clk/clk-divider.c                  | 7 +++----
>>  drivers/clk/hisilicon/clkdivider-hi6220.c  | 2 +-
>>  drivers/clk/nxp/clk-lpc32xx.c              | 2 +-
>>  drivers/clk/qcom/clk-regmap-divider.c      | 2 +-
>>  drivers/clk/sunxi-ng/ccu_div.c             | 2 +-
>>  drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c | 2 +-
>>  drivers/rtc/rtc-ac100.c                    | 6 ++++--
>>  include/linux/clk-provider.h               | 2 +-
>>  8 files changed, 13 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
>> index 4ed516cb7276..b49942b9fe50 100644
>> --- a/drivers/clk/clk-divider.c
>> +++ b/drivers/clk/clk-divider.c
>> @@ -118,12 +118,11 @@ static unsigned int _get_val(const struct clk_div_table *table,
>>  unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
>>                                 unsigned int val,
>>                                 const struct clk_div_table *table,
>> -                               unsigned long flags)
>> +                               unsigned long flags, unsigned long width)
>>  {
>> -     struct clk_divider *divider = to_clk_divider(hw);
>>       unsigned int div;
>>
>> -     div = _get_div(table, val, flags, divider->width);
>> +     div = _get_div(table, val, flags, width);
>>       if (!div) {
>>               WARN(!(flags & CLK_DIVIDER_ALLOW_ZERO),
>>                       "%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
>> @@ -145,7 +144,7 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
>>       val &= div_mask(divider->width);
>>
>>       return divider_recalc_rate(hw, parent_rate, val, divider->table,
>> -                                divider->flags);
>> +                                divider->flags, divider->width);
>>  }
>>
>>  static bool _is_valid_table_div(const struct clk_div_table *table,
>> diff --git a/drivers/clk/hisilicon/clkdivider-hi6220.c b/drivers/clk/hisilicon/clkdivider-hi6220.c
>> index a1c1f684ad58..9f46cf9dcc65 100644
>> --- a/drivers/clk/hisilicon/clkdivider-hi6220.c
>> +++ b/drivers/clk/hisilicon/clkdivider-hi6220.c
>> @@ -56,7 +56,7 @@ static unsigned long hi6220_clkdiv_recalc_rate(struct clk_hw *hw,
>>       val &= div_mask(dclk->width);
>>
>>       return divider_recalc_rate(hw, parent_rate, val, dclk->table,
>> -                                CLK_DIVIDER_ROUND_CLOSEST);
>> +                                CLK_DIVIDER_ROUND_CLOSEST, dclk->width);
>>  }
>>
>>  static long hi6220_clkdiv_round_rate(struct clk_hw *hw, unsigned long rate,
>> diff --git a/drivers/clk/nxp/clk-lpc32xx.c b/drivers/clk/nxp/clk-lpc32xx.c
>> index b669a5c10fee..f5d815f577e0 100644
>> --- a/drivers/clk/nxp/clk-lpc32xx.c
>> +++ b/drivers/clk/nxp/clk-lpc32xx.c
>> @@ -956,7 +956,7 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
>>       val &= div_mask(divider->width);
>>
>>       return divider_recalc_rate(hw, parent_rate, val, divider->table,
>> -                                divider->flags);
>> +                                divider->flags, divider->width);
>>  }
>>
>>  static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
>> diff --git a/drivers/clk/qcom/clk-regmap-divider.c b/drivers/clk/qcom/clk-regmap-divider.c
>> index 53484912301e..928fcc16ee27 100644
>> --- a/drivers/clk/qcom/clk-regmap-divider.c
>> +++ b/drivers/clk/qcom/clk-regmap-divider.c
>> @@ -59,7 +59,7 @@ static unsigned long div_recalc_rate(struct clk_hw *hw,
>>       div &= BIT(divider->width) - 1;
>>
>>       return divider_recalc_rate(hw, parent_rate, div, NULL,
>> -                                CLK_DIVIDER_ROUND_CLOSEST);
>> +                                CLK_DIVIDER_ROUND_CLOSEST, divider->width);
>>  }
>>
>>  const struct clk_ops clk_regmap_div_ops = {
>> diff --git a/drivers/clk/sunxi-ng/ccu_div.c b/drivers/clk/sunxi-ng/ccu_div.c
>> index baa3cf96507b..302a18efd39f 100644
>> --- a/drivers/clk/sunxi-ng/ccu_div.c
>> +++ b/drivers/clk/sunxi-ng/ccu_div.c
>> @@ -71,7 +71,7 @@ static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
>>                                                 parent_rate);
>>
>>       val = divider_recalc_rate(hw, parent_rate, val, cd->div.table,
>> -                               cd->div.flags);
>> +                               cd->div.flags, cd->div.width);
>>
>>       if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
>>               val /= cd->fixed_post_div;
>> diff --git a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c
>> index fe15aa64086f..71fe60e5f01f 100644
>> --- a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c
>> +++ b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_14nm.c
>> @@ -698,7 +698,7 @@ static unsigned long dsi_pll_14nm_postdiv_recalc_rate(struct clk_hw *hw,
>>       val &= div_mask(width);
>>
>>       return divider_recalc_rate(hw, parent_rate, val, NULL,
>> -                                postdiv->flags);
>> +                                postdiv->flags, width);
>>  }
>>
>>  static long dsi_pll_14nm_postdiv_round_rate(struct clk_hw *hw,
>> diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c
>> index 9e336184491c..0282ccc6181c 100644
>> --- a/drivers/rtc/rtc-ac100.c
>> +++ b/drivers/rtc/rtc-ac100.c
>> @@ -137,13 +137,15 @@ static unsigned long ac100_clkout_recalc_rate(struct clk_hw *hw,
>>               div = (reg >> AC100_CLKOUT_PRE_DIV_SHIFT) &
>>                       ((1 << AC100_CLKOUT_PRE_DIV_WIDTH) - 1);
>>               prate = divider_recalc_rate(hw, prate, div,
>> -                                         ac100_clkout_prediv, 0);
>> +                                         ac100_clkout_prediv, 0,
>> +                                         AC100_CLKOUT_PRE_DIV_WIDTH);
>>       }
>>
>>       div = (reg >> AC100_CLKOUT_DIV_SHIFT) &
>>               (BIT(AC100_CLKOUT_DIV_WIDTH) - 1);
>>       return divider_recalc_rate(hw, prate, div, NULL,
>> -                                CLK_DIVIDER_POWER_OF_TWO);
>> +                                CLK_DIVIDER_POWER_OF_TWO,
>> +                                AC100_CLKOUT_DIV_WIDTH);
>>  }
>>
>>  static long ac100_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
>> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
>> index 73ac87f34df9..4c4001086447 100644
>> --- a/include/linux/clk-provider.h
>> +++ b/include/linux/clk-provider.h
>> @@ -412,7 +412,7 @@ extern const struct clk_ops clk_divider_ro_ops;
>>
>>  unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
>>               unsigned int val, const struct clk_div_table *table,
>> -             unsigned long flags);
>> +             unsigned long flags, unsigned long width);
>>  long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent,
>>                              unsigned long rate, unsigned long *prate,
>>                              const struct clk_div_table *table,
>> --
>> 2.14.3
>>
>
> --
> Alexandre Belloni, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com



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