sh: add a reparent function to DIV6 clocks

Add support for reparenting of div6 clocks on SuperH and SH-Mobile SoCs.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 70 insertions, 7 deletions

diff --git a/drivers/sh/clk-cpg.c b/drivers/sh/clk-cpg.c
index f5c80ba9ab1c..8c024b984ed8 100644
--- a/drivers/sh/clk-cpg.c
+++ b/drivers/sh/clk-cpg.c
@@ -68,6 +68,39 @@ static unsigned long sh_clk_div6_recalc(struct clk *clk)
         return clk->freq_table[idx].frequency;
 }
 
+static int sh_clk_div6_set_parent(struct clk *clk, struct clk *parent)
+{
+        struct clk_div_mult_table *table = &sh_clk_div6_table;
+        u32 value;
+        int ret, i;
+
+        if (!clk->parent_table || !clk->parent_num)
+                return -EINVAL;
+
+        /* Search the parent */
+        for (i = 0; i < clk->parent_num; i++)
+                if (clk->parent_table[i] == parent)
+                        break;
+
+        if (i == clk->parent_num)
+                return -ENODEV;
+
+        ret = clk_reparent(clk, parent);
+        if (ret < 0)
+                return ret;
+
+        value = __raw_readl(clk->enable_reg) &
+                ~(((1 << clk->src_width) - 1) << clk->src_shift);
+
+        __raw_writel(value | (i << clk->src_shift), clk->enable_reg);
+
+        /* Rebuild the frequency table */
+        clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
+                             table, &clk->arch_flags);
+
+        return 0;
+}
+
 static int sh_clk_div6_set_rate(struct clk *clk,
                                 unsigned long rate, int algo_id)
 {
@@ -117,7 +150,17 @@ static struct clk_ops sh_clk_div6_clk_ops = {
         .disable        = sh_clk_div6_disable,
 };
 
-int __init sh_clk_div6_register(struct clk *clks, int nr)
+static struct clk_ops sh_clk_div6_reparent_clk_ops = {
+        .recalc         = sh_clk_div6_recalc,
+        .round_rate     = sh_clk_div_round_rate,
+        .set_rate       = sh_clk_div6_set_rate,
+        .enable         = sh_clk_div6_enable,
+        .disable        = sh_clk_div6_disable,
+        .set_parent     = sh_clk_div6_set_parent,
+};
+
+static int __init sh_clk_div6_register_ops(struct clk *clks, int nr,
+                                           struct clk_ops *ops)
 {
         struct clk *clkp;
         void *freq_table;
@@ -136,7 +179,7 @@ int __init sh_clk_div6_register(struct clk *clks, int nr)
         for (k = 0; !ret && (k < nr); k++) {
                 clkp = clks + k;
 
-                clkp->ops = &sh_clk_div6_clk_ops;
+                clkp->ops = ops;
                 clkp->id = -1;
                 clkp->freq_table = freq_table + (k * freq_table_size);
                 clkp->freq_table[nr_divs].frequency = CPUFREQ_TABLE_END;
@@ -147,6 +190,17 @@ int __init sh_clk_div6_register(struct clk *clks, int nr)
         return ret;
 }
 
+int __init sh_clk_div6_register(struct clk *clks, int nr)
+{
+        return sh_clk_div6_register_ops(clks, nr, &sh_clk_div6_clk_ops);
+}
+
+int __init sh_clk_div6_reparent_register(struct clk *clks, int nr)
+{
+        return sh_clk_div6_register_ops(clks, nr,
+                                        &sh_clk_div6_reparent_clk_ops);
+}
+
 static unsigned long sh_clk_div4_recalc(struct clk *clk)
 {
         struct clk_div4_table *d4t = clk->priv;
diff --git a/include/linux/sh_clk.h b/include/linux/sh_clk.h
index 08a07b9a894f..875ce50719a9 100644
--- a/include/linux/sh_clk.h
+++ b/include/linux/sh_clk.h
@@ -142,13 +142,22 @@ int sh_clk_div4_enable_register(struct clk *clks, int nr,
 int sh_clk_div4_reparent_register(struct clk *clks, int nr,
                          struct clk_div4_table *table);
 
-#define SH_CLK_DIV6(_parent, _reg, _flags)      \
-{                                               \
-        .parent = _parent,                      \
-        .enable_reg = (void __iomem *)_reg,     \
-        .flags = _flags,                        \
+#define SH_CLK_DIV6_EXT(_parent, _reg, _flags, _parents,        \
+                        _num_parents, _src_shift, _src_width)   \
+{                                                               \
+        .parent = _parent,                                      \
+        .enable_reg = (void __iomem *)_reg,                     \
+        .flags = _flags,                                        \
+        .parent_table = _parents,                               \
+        .parent_num = _num_parents,                             \
+        .src_shift = _src_shift,                                \
+        .src_width = _src_width,                                \
 }
 
+#define SH_CLK_DIV6(_parent, _reg, _flags)                      \
+        SH_CLK_DIV6_EXT(_parent, _reg, _flags, NULL, 0, 0, 0)
+
 int sh_clk_div6_register(struct clk *clks, int nr);
+int sh_clk_div6_reparent_register(struct clk *clks, int nr);
 
 #endif /* __SH_CLOCK_H */