12 #define pr_fmt(fmt) "clk-frac-synth: " fmt
14 #include <linux/clk-provider.h>
18 #include "clk.h"
27  * Fout= Fin/2*div (division factor)
28  * div is 17 bits:-
29  *	0-13 (fractional part)
30  *	14-16 (integer part)
31  *	div is (16-14 bits).(13-0 bits) (in binary)
33  *	Fout = Fin/(2 * div)
34  *	Fout = ((Fin / 10000)/(2 * div)) * 10000
35  *	Fout = (2^14 * (Fin / 10000)/(2^14 * (2 * div))) * 10000
36  *	Fout = (((Fin / 10000) << 14)/(2 * (div << 14))) * 10000
38  * div << 14 simply 17 bit value written at register.
48 	struct frac_rate_tbl *rtbl = frac->rtbl;  in frac_calc_rate()
52 	prate /= (2 * rtbl[index].div);  in frac_calc_rate()
65 			frac->rtbl_cnt, &unused);  in clk_frac_round_rate()
73 	unsigned int div = 1, val;  in clk_frac_recalc_rate()  local
75 	if (frac->lock)  in clk_frac_recalc_rate()
76 		spin_lock_irqsave(frac->lock, flags);  in clk_frac_recalc_rate()
78 	val = readl_relaxed(frac->reg);  in clk_frac_recalc_rate()
80 	if (frac->lock)  in clk_frac_recalc_rate()
81 		spin_unlock_irqrestore(frac->lock, flags);  in clk_frac_recalc_rate()
83 	div = val & DIV_FACTOR_MASK;  in clk_frac_recalc_rate()
85 	if (!div)  in clk_frac_recalc_rate()
90 	parent_rate = (parent_rate << 14) / (2 * div);  in clk_frac_recalc_rate()
99 	struct frac_rate_tbl *rtbl = frac->rtbl;  in clk_frac_set_rate()
103 	clk_round_rate_index(hw, drate, prate, frac_calc_rate, frac->rtbl_cnt,  in clk_frac_set_rate()
106 	if (frac->lock)  in clk_frac_set_rate()
107 		spin_lock_irqsave(frac->lock, flags);  in clk_frac_set_rate()
109 	val = readl_relaxed(frac->reg) & ~DIV_FACTOR_MASK;  in clk_frac_set_rate()
110 	val |= rtbl[i].div & DIV_FACTOR_MASK;  in clk_frac_set_rate()
111 	writel_relaxed(val, frac->reg);  in clk_frac_set_rate()
113 	if (frac->lock)  in clk_frac_set_rate()
114 		spin_unlock_irqrestore(frac->lock, flags);  in clk_frac_set_rate()
125 struct clk *clk_register_frac(const char *name, const char *parent_name,  in clk_register_frac()
131 	struct clk *clk;  in clk_register_frac()  local
135 		return ERR_PTR(-EINVAL);  in clk_register_frac()
140 		return ERR_PTR(-ENOMEM);  in clk_register_frac()
143 	frac->reg = reg;  in clk_register_frac()
144 	frac->rtbl = rtbl;  in clk_register_frac()
145 	frac->rtbl_cnt = rtbl_cnt;  in clk_register_frac()
146 	frac->lock = lock;  in clk_register_frac()
147 	frac->hw.init = &init;  in clk_register_frac()
155 	clk = clk_register(NULL, &frac->hw);  in clk_register_frac()
156 	if (!IS_ERR_OR_NULL(clk))  in clk_register_frac()
157 		return clk;  in clk_register_frac()
159 	pr_err("clk register failed\n");  in clk_register_frac()