[PATCH 2/7] clk: imx: gate2 support shared counter and relative clock functions

[Dario Binacchi]

From: Michael Trimarchi <michael at amarulasolutions.com>

Add shared counter in order to avoid to swich off clock that
are already used.

Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi at amarulasolutions.com>
---

 drivers/clk/imx/clk-gate2.c | 15 ++++++++++++++-
 drivers/clk/imx/clk.h       | 27 +++++++++++++++++++++++----
 2 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/imx/clk-gate2.c b/drivers/clk/imx/clk-gate2.c
index 40b2d4caab49..da2723023778 100644
--- a/drivers/clk/imx/clk-gate2.c
+++ b/drivers/clk/imx/clk-gate2.c
@@ -20,6 +20,7 @@
 #include <clk-uclass.h>
 #include <dm/device.h>
 #include <dm/devres.h>
+#include <linux/bug.h>
 #include <linux/clk-provider.h>
 #include <clk.h>
 #include "clk.h"
@@ -33,6 +34,7 @@ struct clk_gate2 {
 	u8		bit_idx;
 	u8		cgr_val;
 	u8		flags;
+	unsigned int	*share_count;
 };
 
 #define to_clk_gate2(_clk) container_of(_clk, struct clk_gate2, clk)
@@ -42,6 +44,9 @@ static int clk_gate2_enable(struct clk *clk)
 	struct clk_gate2 *gate = to_clk_gate2(clk);
 	u32 reg;
 
+	if (gate->share_count && (*gate->share_count)++ > 0)
+		return 0;
+
 	reg = readl(gate->reg);
 	reg &= ~(3 << gate->bit_idx);
 	reg |= gate->cgr_val << gate->bit_idx;
@@ -55,6 +60,13 @@ static int clk_gate2_disable(struct clk *clk)
 	struct clk_gate2 *gate = to_clk_gate2(clk);
 	u32 reg;
 
+	if (gate->share_count) {
+		if (WARN_ON(*gate->share_count == 0))
+			return 0;
+		else if (--(*gate->share_count) > 0)
+			return 0;
+	}
+
 	reg = readl(gate->reg);
 	reg &= ~(3 << gate->bit_idx);
 	writel(reg, gate->reg);
@@ -82,7 +94,7 @@ static const struct clk_ops clk_gate2_ops = {
 struct clk *clk_register_gate2(struct device *dev, const char *name,
 		const char *parent_name, unsigned long flags,
 		void __iomem *reg, u8 bit_idx, u8 cgr_val,
-		u8 clk_gate2_flags)
+		u8 clk_gate2_flags, unsigned int *share_count)
 {
 	struct clk_gate2 *gate;
 	struct clk *clk;
@@ -96,6 +108,7 @@ struct clk *clk_register_gate2(struct device *dev, const char *name,
 	gate->bit_idx = bit_idx;
 	gate->cgr_val = cgr_val;
 	gate->flags = clk_gate2_flags;
+	gate->share_count = share_count;
 
 	clk = &gate->clk;
 
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index 46dee35a6735..11f5dca1175b 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -53,7 +53,7 @@ struct clk *imx_clk_pll14xx(const char *name, const char *parent_name,
 struct clk *clk_register_gate2(struct device *dev, const char *name,
 		const char *parent_name, unsigned long flags,
 		void __iomem *reg, u8 bit_idx, u8 cgr_val,
-		u8 clk_gate_flags);
+		u8 clk_gate_flags, unsigned int *share_count);
 
 struct clk *imx_clk_pllv3(enum imx_pllv3_type type, const char *name,
 			  const char *parent_name, void __iomem *base,
@@ -63,7 +63,26 @@ static inline struct clk *imx_clk_gate2(const char *name, const char *parent,
 					void __iomem *reg, u8 shift)
 {
 	return clk_register_gate2(NULL, name, parent, CLK_SET_RATE_PARENT, reg,
-			shift, 0x3, 0);
+			shift, 0x3, 0, NULL);
+}
+
+static inline struct clk *imx_clk_gate2_shared(const char *name,
+					       const char *parent,
+					       void __iomem *reg, u8 shift,
+					       unsigned int *share_count)
+{
+	return clk_register_gate2(NULL, name, parent, CLK_SET_RATE_PARENT, reg,
+				  shift, 0x3, 0, share_count);
+}
+
+static inline struct clk *imx_clk_gate2_shared2(const char *name,
+						const char *parent,
+						void __iomem *reg, u8 shift,
+						unsigned int *share_count)
+{
+	return clk_register_gate2(NULL, name, parent, CLK_SET_RATE_PARENT |
+				  CLK_OPS_PARENT_ENABLE, reg, shift, 0x3, 0,
+				  share_count);
 }
 
 static inline struct clk *imx_clk_gate4(const char *name, const char *parent,
@@ -71,7 +90,7 @@ static inline struct clk *imx_clk_gate4(const char *name, const char *parent,
 {
 	return clk_register_gate2(NULL, name, parent,
 			CLK_SET_RATE_PARENT | CLK_OPS_PARENT_ENABLE,
-			reg, shift, 0x3, 0);
+			reg, shift, 0x3, 0, NULL);
 }
 
 static inline struct clk *imx_clk_gate4_flags(const char *name,
@@ -80,7 +99,7 @@ static inline struct clk *imx_clk_gate4_flags(const char *name,
 {
 	return clk_register_gate2(NULL, name, parent,
 			flags | CLK_SET_RATE_PARENT | CLK_OPS_PARENT_ENABLE,
-			reg, shift, 0x3, 0);
+			reg, shift, 0x3, 0, NULL);
 }
 
 static inline struct clk *imx_clk_fixed_factor(const char *name,
-- 
2.32.0