clk: divider: fix incorrect usage of container_of

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>
diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c
index 9e33618..0282ccc 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,