[PATCH AUTOSEL for 4.15 023/124] clk: divider: fix incorrect usage of container_of

Sasha Levin
2018-03-19T22:38:47Z

From: Jerome Brunet <jbrunet@baylibre.com>

[ Upstream commit 12a26c298d2a8b1cab498533fa65198e49e3afd3 ]

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@baylibre.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
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 7b359afd620e..a6438f50e6db 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 7c925e6211f1..48171b349b88 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,
--
2.14.1