ARM: OMAP4: clock: Convert to common clk

Convert all OMAP4 specific platform files to use COMMON clk
and keep all the changes under the CONFIG_COMMON_CLK macro check
so it does not break any existing code. At a later point switch
to COMMON clk and get rid of all old/legacy code.

This converts all apis which will be called directly from COMMON
clk to take a struct clk_hw parameter, and all the internal platform
apis to take a struct clk_hw_omap parameter.

Changes are based off the original patch from Mike Turquette.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: created new omap2_clksel_find_parent_index() rather than
 modifying omap2_init_clksel_parent(); moved clkhwops_iclk_wait to
 clkt_iclk.c to fix OMAP4-only builds; added clk-provider.h include to clock.h
 to try to fix some 3430-builds]
[mturquette@ti.com: squash patch for omap2_clkops_{en,dis}able_clkdm;
 omap2_dflt_clk_is_enabled should not enable clocks]
Signed-off-by: Mike Turquette <mturquette@ti.com>
[paul@pwsan.com: fix compiler warning; update to apply; added kerneldoc on
 non-trivial new functions; added the dpll3xxx clockdomain modifications]
Signed-off-by: Paul Walmsley <paul@pwsan.com>

arch/arm/mach-omap2/clkt_clksel.c

@@ -41,7 +41,11 @@
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
+#ifdef CONFIG_COMMON_CLK
+#include <linux/clk-provider.h>
+#else
 #include <linux/clk.h>
+#endif
 #include <linux/io.h>
 #include <linux/bug.h>
 
@@ -58,19 +62,30 @@
  * the element associated with the supplied parent clock address.
  * Returns a pointer to the struct clksel on success or NULL on error.
  */
+#ifdef CONFIG_COMMON_CLK
+static const struct clksel *_get_clksel_by_parent(struct clk_hw_omap *clk,
+#else
 static const struct clksel *_get_clksel_by_parent(struct clk *clk,
+#endif
 						  struct clk *src_clk)
 {
 	const struct clksel *clks;
 
+	if (!src_clk)
+		return NULL;
+
 	for (clks = clk->clksel; clks->parent; clks++)
 		if (clks->parent == src_clk)
 			break; /* Found the requested parent */
 
 	if (!clks->parent) {
 		/* This indicates a data problem */
 		WARN(1, "clock: %s: could not find parent clock %s in clksel array\n",
+#ifdef CONFIG_COMMON_CLK
+		     __clk_get_name(clk->hw.clk), __clk_get_name(src_clk));
+#else
 		     __clk_get_name(clk), __clk_get_name(src_clk));
+#endif
 		return NULL;
 	}
 
@@ -92,6 +107,7 @@ static const struct clksel *_get_clksel_by_parent(struct clk *clk,
  * success (in this latter case, the corresponding register bitfield
  * value is passed back in the variable pointed to by @field_val)
  */
+#ifndef CONFIG_COMMON_CLK
 static u8 _get_div_and_fieldval(struct clk *src_clk, struct clk *clk,
 				u32 *field_val)
 {
@@ -134,6 +150,7 @@ static u8 _get_div_and_fieldval(struct clk *src_clk, struct clk *clk,
 
 	return max_div;
 }
+#endif
 
 /**
  * _write_clksel_reg() - program a clock's clksel register in hardware
@@ -148,7 +165,11 @@ static u8 _get_div_and_fieldval(struct clk *src_clk, struct clk *clk,
  * take into account any time the hardware might take to switch the
  * clock source.
  */
+#ifdef CONFIG_COMMON_CLK
+static void _write_clksel_reg(struct clk_hw_omap *clk, u32 field_val)
+#else
 static void _write_clksel_reg(struct clk *clk, u32 field_val)
+#endif
 {
 	u32 v;
 
@@ -171,13 +192,22 @@ static void _write_clksel_reg(struct clk *clk, u32 field_val)
  * before calling.  Returns 0 on error or returns the actual integer divisor
  * upon success.
  */
+#ifdef CONFIG_COMMON_CLK
+static u32 _clksel_to_divisor(struct clk_hw_omap *clk, u32 field_val)
+#else
 static u32 _clksel_to_divisor(struct clk *clk, u32 field_val)
+#endif
 {
 	const struct clksel *clks;
 	const struct clksel_rate *clkr;
 	struct clk *parent;
 
+#ifdef CONFIG_COMMON_CLK
+	parent = __clk_get_parent(clk->hw.clk);
+#else
 	parent = __clk_get_parent(clk);
+#endif
+
 	clks = _get_clksel_by_parent(clk, parent);
 	if (!clks)
 		return 0;
@@ -193,7 +223,12 @@ static u32 _clksel_to_divisor(struct clk *clk, u32 field_val)
 	if (!clkr->div) {
 		/* This indicates a data error */
 		WARN(1, "clock: %s: could not find fieldval %d for parent %s\n",
+#ifdef CONFIG_COMMON_CLK
+		     __clk_get_name(clk->hw.clk), field_val,
+		     __clk_get_name(parent));
+#else
 		     __clk_get_name(clk), field_val, __clk_get_name(parent));
+#endif
 		return 0;
 	}
 
@@ -210,7 +245,11 @@ static u32 _clksel_to_divisor(struct clk *clk, u32 field_val)
  * register field value _before_ left-shifting (i.e., LSB is at bit
  * 0); or returns 0xFFFFFFFF (~0) upon error.
  */
+#ifdef CONFIG_COMMON_CLK
+static u32 _divisor_to_clksel(struct clk_hw_omap *clk, u32 div)
+#else
 static u32 _divisor_to_clksel(struct clk *clk, u32 div)
+#endif
 {
 	const struct clksel *clks;
 	const struct clksel_rate *clkr;
@@ -219,7 +258,11 @@ static u32 _divisor_to_clksel(struct clk *clk, u32 div)
 	/* should never happen */
 	WARN_ON(div == 0);
 
+#ifdef CONFIG_COMMON_CLK
+	parent = __clk_get_parent(clk->hw.clk);
+#else
 	parent = __clk_get_parent(clk);
+#endif
 	clks = _get_clksel_by_parent(clk, parent);
 	if (!clks)
 		return ~0;
@@ -234,7 +277,12 @@ static u32 _divisor_to_clksel(struct clk *clk, u32 div)
 
 	if (!clkr->div) {
 		pr_err("clock: %s: could not find divisor %d for parent %s\n",
+#ifdef CONFIG_COMMON_CLK
+		       __clk_get_name(clk->hw.clk), div,
+		       __clk_get_name(parent));
+#else
 		       __clk_get_name(clk), div, __clk_get_name(parent));
+#endif
 		return ~0;
 	}
 
@@ -249,7 +297,11 @@ static u32 _divisor_to_clksel(struct clk *clk, u32 div)
  * into the hardware, convert it into the actual divisor value, and
  * return it; or return 0 on error.
  */
+#ifdef CONFIG_COMMON_CLK
+static u32 _read_divisor(struct clk_hw_omap *clk)
+#else
 static u32 _read_divisor(struct clk *clk)
+#endif
 {
 	u32 v;
 
@@ -277,7 +329,12 @@ static u32 _read_divisor(struct clk *clk)
  *
  * Returns the rounded clock rate or returns 0xffffffff on error.
  */
+#ifdef CONFIG_COMMON_CLK
+u32 omap2_clksel_round_rate_div(struct clk_hw_omap *clk,
+						 unsigned long target_rate,
+#else
 u32 omap2_clksel_round_rate_div(struct clk *clk, unsigned long target_rate,
+#endif
 				u32 *new_div)
 {
 	unsigned long test_rate;
@@ -288,9 +345,14 @@ u32 omap2_clksel_round_rate_div(struct clk *clk, unsigned long target_rate,
 	unsigned long parent_rate;
 	const char *clk_name;
 
+#ifdef CONFIG_COMMON_CLK
+	parent = __clk_get_parent(clk->hw.clk);
+	clk_name = __clk_get_name(clk->hw.clk);
+#else
 	parent = __clk_get_parent(clk);
-	parent_rate = __clk_get_rate(parent);
 	clk_name = __clk_get_name(clk);
+#endif
+	parent_rate = __clk_get_rate(parent);
 
 	if (!clk->clksel || !clk->clksel_mask)
 		return ~0;
@@ -340,6 +402,63 @@ u32 omap2_clksel_round_rate_div(struct clk *clk, unsigned long target_rate,
  * (i.e., those used in struct clk field function pointers, etc.)
  */
 
+#ifdef CONFIG_COMMON_CLK
+/**
+ * omap2_clksel_find_parent_index() - return the array index of the current
+ * hardware parent of @hw
+ * @hw: struct clk_hw * to find the current hardware parent of
+ *
+ * Given a struct clk_hw pointer @hw to the 'hw' member of a struct
+ * clk_hw_omap record representing a source-selectable hardware clock,
+ * read the hardware register and determine what its parent is
+ * currently set to.  Intended to be called only by the common clock
+ * framework struct clk_hw_ops.get_parent function pointer.  Return
+ * the array index of this parent clock upon success -- there is no
+ * way to return an error, so if we encounter an error, just WARN()
+ * and pretend that we know that we're doing.
+ */
+u8 omap2_clksel_find_parent_index(struct clk_hw *hw)
+{
+	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+	const struct clksel *clks;
+	const struct clksel_rate *clkr;
+	u32 r, found = 0;
+	struct clk *parent;
+	const char *clk_name;
+	int ret = 0, f = 0;
+
+	parent = __clk_get_parent(hw->clk);
+	clk_name = __clk_get_name(hw->clk);
+
+	/* XXX should be able to return an error */
+	WARN((!clk->clksel || !clk->clksel_mask),
+	     "clock: %s: attempt to call on a non-clksel clock", clk_name);
+
+	r = __raw_readl(clk->clksel_reg) & clk->clksel_mask;
+	r >>= __ffs(clk->clksel_mask);
+
+	for (clks = clk->clksel; clks->parent && !found; clks++) {
+		for (clkr = clks->rates; clkr->div && !found; clkr++) {
+			if (!(clkr->flags & cpu_mask))
+				continue;
+
+			if (clkr->val == r) {
+				found = 1;
+				ret = f;
+			}
+		}
+		f++;
+	}
+
+	/* This indicates a data error */
+	WARN(!found, "clock: %s: init parent: could not find regval %0x\n",
+	     clk_name, r);
+
+	return ret;
+}
+
+#else
+
 /**
  * omap2_init_clksel_parent() - set a clksel clk's parent field from the hdwr
  * @clk: OMAP clock struct ptr to use
@@ -393,6 +512,8 @@ void omap2_init_clksel_parent(struct clk *clk)
 	return;
 }
 
+#endif
+
 /**
  * omap2_clksel_recalc() - function ptr to pass via struct clk .recalc field
  * @clk: struct clk *
@@ -402,6 +523,28 @@ void omap2_init_clksel_parent(struct clk *clk)
  * function.  Returns the clock's current rate, based on its parent's rate
  * and its current divisor setting in the hardware.
  */
+#ifdef CONFIG_COMMON_CLK
+unsigned long omap2_clksel_recalc(struct clk_hw *hw, unsigned long parent_rate)
+{
+	unsigned long rate;
+	u32 div = 0;
+	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+
+	if (!parent_rate)
+		return 0;
+
+	div = _read_divisor(clk);
+	if (!div)
+		rate = parent_rate;
+	else
+		rate = parent_rate / div;
+
+	pr_debug("%s: recalc'd %s's rate to %lu (div %d)\n", __func__,
+		 __clk_get_name(hw->clk), rate, div);
+
+	return rate;
+}
+#else
 unsigned long omap2_clksel_recalc(struct clk *clk)
 {
 	unsigned long rate;
@@ -420,6 +563,7 @@ unsigned long omap2_clksel_recalc(struct clk *clk)
 
 	return rate;
 }
+#endif
 
 /**
  * omap2_clksel_round_rate() - find rounded rate for the given clock and rate
@@ -432,8 +576,15 @@ unsigned long omap2_clksel_recalc(struct clk *clk)
  *
  * Returns the rounded clock rate or returns 0xffffffff on error.
  */
+#ifdef CONFIG_COMMON_CLK
+long omap2_clksel_round_rate(struct clk_hw *hw, unsigned long target_rate,
+			unsigned long *parent_rate)
+{
+	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+#else
 long omap2_clksel_round_rate(struct clk *clk, unsigned long target_rate)
 {
+#endif
 	u32 new_div;
 
 	return omap2_clksel_round_rate_div(clk, target_rate, &new_div);
@@ -454,8 +605,15 @@ long omap2_clksel_round_rate(struct clk *clk, unsigned long target_rate)
  * is changed, they will all be affected without any notification.
  * Returns -EINVAL upon error, or 0 upon success.
  */
+#ifdef CONFIG_COMMON_CLK
+int omap2_clksel_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+#else
 int omap2_clksel_set_rate(struct clk *clk, unsigned long rate)
 {
+#endif
 	u32 field_val, validrate, new_div = 0;
 
 	if (!clk->clksel || !clk->clksel_mask)
@@ -471,11 +629,16 @@ int omap2_clksel_set_rate(struct clk *clk, unsigned long rate)
 
 	_write_clksel_reg(clk, field_val);
 
-	clk->rate = __clk_get_rate(__clk_get_parent(clk)) / new_div;
-
+#ifdef CONFIG_COMMON_CLK
+	pr_debug("clock: %s: set rate to %ld\n", __clk_get_name(hw->clk),
+		 __clk_get_rate(hw->clk));
+#else
 	pr_debug("clock: %s: set rate to %ld\n", __clk_get_name(clk),
 		 __clk_get_rate(clk));
 
+	clk->rate = __clk_get_rate(__clk_get_parent(clk)) / new_div;
+#endif
+
 	return 0;
 }
 
@@ -499,6 +662,18 @@ int omap2_clksel_set_rate(struct clk *clk, unsigned long rate)
  * affected without any notification.  Returns -EINVAL upon error, or
  * 0 upon success.
  */
+#ifdef CONFIG_COMMON_CLK
+int omap2_clksel_set_parent(struct clk_hw *hw, u8 field_val)
+{
+	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+
+	if (!clk->clksel || !clk->clksel_mask)
+		return -EINVAL;
+
+	_write_clksel_reg(clk, field_val);
+	return 0;
+}
+#else
 int omap2_clksel_set_parent(struct clk *clk, struct clk *new_parent)
 {
 	u32 field_val = 0;
@@ -510,7 +685,6 @@ int omap2_clksel_set_parent(struct clk *clk, struct clk *new_parent)
 	parent_div = _get_div_and_fieldval(new_parent, clk, &field_val);
 	if (!parent_div)
 		return -EINVAL;
-
 	_write_clksel_reg(clk, field_val);
 
 	clk_reparent(clk, new_parent);
@@ -520,11 +694,11 @@ int omap2_clksel_set_parent(struct clk *clk, struct clk *new_parent)
 
 	if (parent_div > 0)
 		__clk_get_rate(clk) /= parent_div;
-
 	pr_debug("clock: %s: set parent to %s (new rate %ld)\n",
 		 __clk_get_name(clk),
 		 __clk_get_name(__clk_get_parent(clk)),
 		 __clk_get_rate(clk));
 
 	return 0;
 }
+#endif