[PATCH V6 5/9] clk: imx: add imx7ulp composite clk support

[A.s. Dong]

The imx composite clk is designed for Peripheral Clock Control (PCC)
module observed in IMX ULP SoC series.

NOTE pcc can only be operated when clk is gated.

Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
Cc: Anson Huang <Anson.Huang@xxxxxxx>
Cc: Bai Ping <ping.bai@xxxxxxx>
Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>

---
ChangeLog:
v4->v5:
 * rename to clk-composite-7ulp.c as we have another
   clk-composite-8m.c, function name also changed accordingly
v3->v4:
 * no changes
v2->v3:
 * no changes
v1->v2:
 * remove an unneeded blank line change
 * use clk_hw_register
---
 drivers/clk/imx/Makefile             |  1 +
 drivers/clk/imx/clk-composite-7ulp.c | 85 ++++++++++++++++++++++++++++++++++++
 drivers/clk/imx/clk.h                |  6 +++
 3 files changed, 92 insertions(+)
 create mode 100644 drivers/clk/imx/clk-composite-7ulp.c

diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
index e7248de..a5cab3e 100644
--- a/drivers/clk/imx/Makefile
+++ b/drivers/clk/imx/Makefile
@@ -4,6 +4,7 @@ obj-y += \
 	clk.o \
 	clk-busy.o \
 	clk-cpu.o \
+	clk-composite-7ulp.o \
 	clk-divider-gate.o \
 	clk-fixup-div.o \
 	clk-fixup-mux.o \
diff --git a/drivers/clk/imx/clk-composite-7ulp.c b/drivers/clk/imx/clk-composite-7ulp.c
new file mode 100644
index 0000000..22f679c
--- /dev/null
+++ b/drivers/clk/imx/clk-composite-7ulp.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017~2018 NXP
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#define PCG_PCS_SHIFT	24
+#define PCG_PCS_MASK	0x7
+#define PCG_CGC_SHIFT	30
+#define PCG_FRAC_SHIFT	3
+#define PCG_FRAC_WIDTH	1
+#define PCG_FRAC_MASK	BIT(3)
+#define PCG_PCD_SHIFT	0
+#define PCG_PCD_WIDTH	3
+#define PCG_PCD_MASK	0x7
+
+struct clk_hw *imx7ulp_clk_composite(const char *name,
+				     const char * const *parent_names,
+				     int num_parents, bool mux_present,
+				     bool rate_present, bool gate_present,
+				     void __iomem *reg)
+{
+	struct clk_hw *mux_hw = NULL, *fd_hw = NULL, *gate_hw = NULL;
+	struct clk_fractional_divider *fd = NULL;
+	struct clk_gate *gate = NULL;
+	struct clk_mux *mux = NULL;
+	struct clk_hw *hw;
+
+	if (mux_present) {
+		mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+		if (!mux)
+			return ERR_PTR(-ENOMEM);
+		mux_hw = &mux->hw;
+		mux->reg = reg;
+		mux->shift = PCG_PCS_SHIFT;
+		mux->mask = PCG_PCS_MASK;
+	}
+
+	if (rate_present) {
+		fd = kzalloc(sizeof(*fd), GFP_KERNEL);
+		if (!fd) {
+			kfree(mux);
+			return ERR_PTR(-ENOMEM);
+		}
+		fd_hw = &fd->hw;
+		fd->reg = reg;
+		fd->mshift = PCG_FRAC_SHIFT;
+		fd->mwidth = PCG_FRAC_WIDTH;
+		fd->mmask  = PCG_FRAC_MASK;
+		fd->nshift = PCG_PCD_SHIFT;
+		fd->nwidth = PCG_PCD_WIDTH;
+		fd->nmask = PCG_PCD_MASK;
+		fd->flags = CLK_FRAC_DIVIDER_ZERO_BASED;
+	}
+
+	if (gate_present) {
+		gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+		if (!gate) {
+			kfree(mux);
+			kfree(fd);
+			return ERR_PTR(-ENOMEM);
+		}
+		gate_hw = &gate->hw;
+		gate->reg = reg;
+		gate->bit_idx = PCG_CGC_SHIFT;
+	}
+
+	hw = clk_hw_register_composite(NULL, name, parent_names, num_parents,
+				       mux_hw, &clk_mux_ops, fd_hw,
+				       &clk_fractional_divider_ops, gate_hw,
+				       &clk_gate_ops, CLK_SET_RATE_GATE |
+				       CLK_SET_PARENT_GATE);
+	if (IS_ERR(hw)) {
+		kfree(mux);
+		kfree(fd);
+		kfree(gate);
+	}
+
+	return hw;
+}
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index ebeb754..2e3bcfa 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -71,6 +71,12 @@ struct clk *imx_clk_busy_mux(const char *name, void __iomem *reg, u8 shift,
 			     u8 width, void __iomem *busy_reg, u8 busy_shift,
 			     const char **parent_names, int num_parents);
 
+struct clk_hw *imx7ulp_clk_composite(const char *name,
+				     const char * const *parent_names,
+				     int num_parents, bool mux_present,
+				     bool rate_present, bool gate_present,
+				     void __iomem *reg);
+
 struct clk *imx_clk_fixup_divider(const char *name, const char *parent,
 				  void __iomem *reg, u8 shift, u8 width,
 				  void (*fixup)(u32 *val));
-- 
2.7.4