[2/2] clk: Add support for Renesas PhiClock clock generator

diff --git a/MAINTAINERS b/MAINTAINERS
index 7eabe930b..0a8b429e1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17645,6 +17645,7 @@  RENESAS PHICLOCK CLOCK DRIVER
 M:	Alex Helms <alexander.helms.jy@renesas.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/clock/renesas,phiclock.yaml
+F:	drivers/clk/clk-phiclock.c
 
 RESET CONTROLLER FRAMEWORK
 M:	Philipp Zabel <p.zabel@pengutronix.de>
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index d79905f3e..6bcdde0f0 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -386,6 +386,15 @@  config COMMON_CLK_VC7
 	  Renesas Versaclock7 is a family of configurable clock generator
 	  and jitter attenuator ICs with fractional and integer dividers.
 
+config COMMON_CLK_PHICLOCK
+	tristate "Clock driver for Renesas PhiClock devices"
+	depends on I2C
+	depends on OF
+	select REGMAP_I2C
+	help
+	  Renesas PhiClock is a clock generator with a fractional divider
+	  and spread spectrum support.
+
 config COMMON_CLK_STM32MP135
 	def_bool COMMON_CLK && MACH_STM32MP13
 	help
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index e3ca0d058..6b12861f7 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -52,6 +52,7 @@  obj-$(CONFIG_ARCH_NPCM7XX)	    	+= clk-npcm7xx.o
 obj-$(CONFIG_ARCH_NSPIRE)		+= clk-nspire.o
 obj-$(CONFIG_COMMON_CLK_OXNAS)		+= clk-oxnas.o
 obj-$(CONFIG_COMMON_CLK_PALMAS)		+= clk-palmas.o
+obj-$(CONFIG_COMMON_CLK_PHICLOCK)	+= clk-phiclock.o
 obj-$(CONFIG_CLK_LS1028A_PLLDIG)	+= clk-plldig.o
 obj-$(CONFIG_COMMON_CLK_PWM)		+= clk-pwm.o
 obj-$(CONFIG_CLK_QORIQ)			+= clk-qoriq.o
diff --git a/drivers/clk/clk-phiclock.c b/drivers/clk/clk-phiclock.c
new file mode 100644
index 000000000..cff1547e6
--- /dev/null
+++ b/drivers/clk/clk-phiclock.c
@@ -0,0 +1,729 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common clock framework driver for the PhiClock 9FGV1006 clock generator.
+ *
+ * Copyright (c) 2022 Renesas Electronics Corporation
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/i2c.h>
+#include <linux/math64.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/swab.h>
+
+/* VCO range is 2.3GHz to 2.6GHz */
+#define PHICLOCK_FVCO_MIN		2300000000UL
+#define PHICLOCK_FVCO_MAX		2600000000UL
+
+/* FOUT range is 10MHz to 325MHz */
+#define PHICLOCK_FOUT_MIN		10000000UL
+#define PHICLOCK_FOUT_MAX		325000000UL
+
+/* FPFD max frequency is 160MHz */
+#define PHICLOCK_FPFD_MAX		160000000UL
+
+#define PHICLOCK_NUM_CLKS		4
+#define PHICLOCK_REF0			0
+#define PHICLOCK_OUT			1
+#define PHICLOCK_OUT0			2
+#define PHICLOCK_OUT1			3
+
+#define PHICLOCK_FBFRAC_BITS		16
+#define PHICLOCK_FBFRAC_DIVISOR		BIT(PHICLOCK_FBFRAC_BITS)
+
+#define PHICLOCK_FBDIV_MIN		12
+#define PHICLOCK_FBDIV_MAX		255
+
+#define PHICLOCK_OUTDIV_MIN		8
+#define PHICLOCK_OUTDIV_MAX		4095
+
+#define PHICLOCK_REG_REF0		0x01
+#define PHICLOCK_REG_OUT0		0x05
+#define PHICLOCK_REG_OUT1		0x0b
+#define PHICLOCK_REG_SS_CNFG_PERIOD	0x10
+#define PHICLOCK_REG_FBINT		0x12
+#define PHICLOCK_REG_FBFRAC		0x13
+#define PHICLOCK_REG_SS_STEP		0x15
+#define PHICLOCK_REG_FBCNFG		0x18
+#define PHICLOCK_REG_CALIBRATION	0x1a
+#define PHICLOCK_REG_OUTDIV		0x21
+#define PHICLOCK_REG_DOUBLER		0x25
+
+#define PHICLOCK_REF_EN_MASK		0x40
+#define PHICLOCK_OUT_EN_MASK		0x80
+#define PHICLOCK_FBMODE_MASK		0x02
+#define PHICLOCK_OUTDIV_11_8_MASK	0xf0
+#define PHICLOCK_DOUBLER_MASK		0x20
+#define PHICLOCK_VCO_CAL_MASK		0x80
+#define PHICLOCK_SS_EN_MASK		0x80
+#define PHICLOCK_SS_PERIOD_11_8_MASK	0x0f
+
+enum phiclock_pll_mode {
+	PLL_MODE_FRAC,
+	PLL_MODE_INT,
+};
+
+enum phiclock_ss_direction {
+	SS_DOWN,
+	SS_CENTER,
+};
+
+enum phiclock_model {
+	PHICLOCK_9FGV1006,
+};
+
+struct phiclock_data;
+
+struct phiclock_clk_hw {
+	struct clk_hw hw;
+	struct clk_init_data init;
+	struct phiclock_data *phiclock;
+	unsigned int idx;
+	u8 enabled;
+};
+
+struct phiclock_data {
+	struct regmap *regmap;
+	struct i2c_client *i2c_client;
+	struct clk *xin_clkin_clk;
+	struct phiclock_clk_hw hw[PHICLOCK_NUM_CLKS];
+	enum phiclock_model model;
+	enum phiclock_ss_direction ss_direction;
+	u16 ss_amount;
+	u16 ss_modulation;
+	u32 fvco;
+	u32 fout;
+	u8 doubler;
+	u8 fbint;
+	u16 fbfrac;
+	u16 outdiv;
+	u8 ss_en;
+	u16 ss_period;
+	u16 ss_step;
+};
+
+static inline struct phiclock_clk_hw *to_phiclock_clk(struct clk_hw *hw)
+{
+	return container_of(hw, struct phiclock_clk_hw, hw);
+}
+
+static int phiclock_get_en_reg(unsigned int idx, unsigned int *reg, unsigned int *mask)
+{
+	switch (idx) {
+	case PHICLOCK_REF0:
+		*reg = PHICLOCK_REG_REF0;
+		*mask = PHICLOCK_REF_EN_MASK;
+		break;
+	case PHICLOCK_OUT0:
+		*reg = PHICLOCK_REG_OUT0;
+		*mask = PHICLOCK_OUT_EN_MASK;
+		break;
+	case PHICLOCK_OUT1:
+		*reg = PHICLOCK_REG_OUT1;
+		*mask = PHICLOCK_OUT_EN_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static u32 phiclock_calc_fvco(struct phiclock_data *phiclock)
+{
+	u64 fref, fvco;
+	u8 doubler;
+
+	doubler = phiclock->doubler ? 2 : 1;
+	fref = clk_get_rate(phiclock->xin_clkin_clk) * doubler;
+
+	fvco = 2 * ((fref * phiclock->fbint) +
+		div_u64(fref * phiclock->fbfrac, PHICLOCK_FBFRAC_DIVISOR));
+
+	return (u32)fvco;
+}
+
+static int phiclock_get_divs(struct phiclock_data *phiclock, u8 *doubler, u8 *fbint, u16 *fbfrac,
+			     u16 *outdiv)
+{
+	int ret;
+	unsigned int tmp;
+	u8 reg[3];
+
+	ret = regmap_bulk_read(phiclock->regmap, PHICLOCK_REG_FBINT, reg, 3);
+	if (ret)
+		return ret;
+
+	*fbint = reg[0];
+	*fbfrac = (reg[1] << 8) + reg[2];
+
+	ret = regmap_bulk_read(phiclock->regmap, PHICLOCK_REG_OUTDIV, reg, 2);
+	if (ret)
+		return ret;
+
+	*outdiv = ((reg[1] & PHICLOCK_OUTDIV_11_8_MASK) << 8) + reg[0];
+	if (*outdiv < PHICLOCK_OUTDIV_MIN)
+		*outdiv = PHICLOCK_OUTDIV_MIN;
+	if (*outdiv > PHICLOCK_OUTDIV_MAX)
+		*outdiv = PHICLOCK_OUTDIV_MAX;
+
+	ret = regmap_read(phiclock->regmap, PHICLOCK_REG_DOUBLER, &tmp);
+	if (ret)
+		return ret;
+
+	*doubler = (tmp & PHICLOCK_DOUBLER_MASK) >> 5;
+
+	pr_debug("doubler: %u, fbint: %u, fbfrac: %u, outdiv: %u\n",
+		 *doubler, *fbint, *fbfrac, *outdiv);
+
+	return ret;
+}
+
+static int phiclock_get_ss(struct phiclock_data *phiclock, u8 *ss_en, u16 *ss_period, u16 *ss_step)
+{
+	int ret;
+	u8 reg[2];
+
+	*ss_en = 0;
+	*ss_period = 0;
+	*ss_step = 0;
+
+	ret = regmap_bulk_read(phiclock->regmap, PHICLOCK_REG_SS_CNFG_PERIOD, reg, 2);
+	if (ret)
+		return ret;
+
+	*ss_en = !!(reg[0] & PHICLOCK_SS_EN_MASK);
+	*ss_period = ((reg[0] & PHICLOCK_SS_PERIOD_11_8_MASK) << 8) + reg[1];
+
+	ret = regmap_bulk_read(phiclock->regmap, PHICLOCK_REG_SS_STEP, reg, 2);
+	if (ret)
+		return ret;
+
+	*ss_step = (reg[0] << 8) + reg[1];
+
+	pr_debug("ss_en: %u, ss_period: %u, ss_step: %u\n", *ss_en, *ss_period, *ss_step);
+
+	return ret;
+}
+
+static int phiclock_get_defaults(struct phiclock_data *phiclock)
+{
+	int ret;
+	unsigned int ref0, out0, out1;
+
+	ret = phiclock_get_divs(phiclock, &phiclock->doubler, &phiclock->fbint, &phiclock->fbfrac,
+				&phiclock->outdiv);
+	if (ret)
+		return ret;
+
+	phiclock->fvco = phiclock_calc_fvco(phiclock);
+	phiclock->fout = phiclock->fvco / phiclock->outdiv;
+
+	ret = phiclock_get_ss(phiclock, &phiclock->ss_en, &phiclock->ss_period, &phiclock->ss_step);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(phiclock->regmap, PHICLOCK_REG_REF0, &ref0);
+	ret = regmap_read(phiclock->regmap, PHICLOCK_REG_OUT0, &out0);
+	ret = regmap_read(phiclock->regmap, PHICLOCK_REG_OUT1, &out1);
+	if (ret)
+		return ret;
+
+	ref0 = (ref0 & PHICLOCK_REF_EN_MASK) >> __ffs(PHICLOCK_REF_EN_MASK);
+	out0 = (out0 & PHICLOCK_OUT_EN_MASK) >> __ffs(PHICLOCK_OUT_EN_MASK);
+	out1 = (out1 & PHICLOCK_OUT_EN_MASK) >> __ffs(PHICLOCK_OUT_EN_MASK);
+	phiclock->hw[PHICLOCK_REF0].enabled = ref0;
+	phiclock->hw[PHICLOCK_OUT0].enabled = out0;
+	phiclock->hw[PHICLOCK_OUT1].enabled = out1;
+
+	pr_debug("doubler: %u, fbint: %u, fbfrac: %u, outdiv: %u, fvco: %u, fout: %u\n",
+		 phiclock->doubler, phiclock->fbint, phiclock->fbfrac, phiclock->outdiv,
+		 phiclock->fvco, phiclock->fout);
+
+	pr_debug("ref0_en: %u, out0_en: %u, out1_en: %u\n", ref0, out0, out1);
+
+	pr_debug("ss_en: %u, ss_period: %u, ss_step: %u\n",
+		 phiclock->ss_en, phiclock->ss_period, phiclock->ss_step);
+
+	return ret;
+}
+
+static int phiclock_calc_divs(const unsigned long frequency, const struct phiclock_data *phiclock,
+			      u8 *doubler, u8 *fbint, u16 *fbfrac, u16 *outdiv, u32 *fout,
+			      u32 *fvco, u16 *ss_period, u16 *ss_step)
+{
+	u16 outdivstart;
+	u32 fpfd;
+	unsigned long fin;
+	bool found = false, allow_frac = false;
+	bool ss_en = phiclock->ss_en && phiclock->ss_amount && phiclock->ss_modulation;
+
+	if (frequency == 0)
+		return -EINVAL;
+
+	if (phiclock->fbint == 0)
+		return -EINVAL;
+
+	fin = clk_get_rate(phiclock->xin_clkin_clk);
+	*doubler = 2 * fin <= PHICLOCK_FPFD_MAX ? 1 : 0;
+	*fbint = PHICLOCK_FBDIV_MIN;
+	*fbfrac = 0;
+	*outdiv = PHICLOCK_OUTDIV_MIN;
+	*fout = PHICLOCK_FOUT_MIN;
+	*fvco = *outdiv * frequency;
+
+	fpfd = fin * (*doubler + 1);
+	outdivstart = 1 + (PHICLOCK_FVCO_MIN / frequency);
+
+	if (ss_en)
+		allow_frac = true;
+
+retry:
+	for (*outdiv = outdivstart; *outdiv <= PHICLOCK_OUTDIV_MAX; ++(*outdiv)) {
+		*fvco = *outdiv * frequency;
+		if (*fvco > PHICLOCK_FVCO_MAX) {
+			allow_frac = true;
+			goto retry;
+		}
+
+		*fbint = (*fvco >> 1) / fpfd;
+		*fbfrac = (*fvco >> 1) % fpfd;
+
+		if (*fbint < PHICLOCK_FBDIV_MIN)
+			*fbint = PHICLOCK_FBDIV_MIN;
+		if (*fbint > PHICLOCK_FBDIV_MAX)
+			*fbint = PHICLOCK_FBDIV_MAX;
+
+		if (*fbfrac == 0) {
+			found = true;
+			break;
+		}
+
+		if (allow_frac) {
+			*fbfrac = 1 + div_u64(((u64)*fvco >> 1) % fpfd << PHICLOCK_FBFRAC_BITS,
+					      fpfd);
+			found = true;
+			break;
+		}
+	}
+
+	if (!found)
+		return -EINVAL;
+
+	if (*fvco < PHICLOCK_FVCO_MIN || *fvco > PHICLOCK_FVCO_MAX)
+		return -EINVAL;
+
+	if (ss_en) {
+		unsigned int ss_amount = phiclock->ss_amount;
+
+		if (phiclock->ss_direction == SS_CENTER) {
+			u64 num, den;
+			u32 rem;
+
+			num = (u64)*fbint * PHICLOCK_FBFRAC_DIVISOR + *fbfrac;
+			num *= 10000 + phiclock->ss_amount;
+			den = 10000 * PHICLOCK_FBFRAC_DIVISOR;
+			*fbint = div_u64_rem(num, den, &rem);
+			*fbfrac = rem / 10000;
+
+			/* center spread requires peak-peak */
+			ss_amount *= 2;
+		}
+
+		*ss_period = fpfd / (4 * phiclock->ss_modulation);
+		*ss_step = (u16)div_u64((ss_amount * (u64)*fbint) << 24, 20000 * *ss_period);
+	}
+
+	*fvco = 2 * (((u64)fpfd * *fbint) + div_u64((u64)fpfd * *fbfrac, PHICLOCK_FBFRAC_DIVISOR));
+	*fout = *fvco / *outdiv;
+
+	if (*fout < PHICLOCK_FOUT_MIN || *fout > PHICLOCK_FOUT_MAX)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int phiclock_update_frequency(struct phiclock_data *phiclock)
+{
+	int ret;
+	enum phiclock_pll_mode pll_mode;
+	u8 reg[3];
+
+	pll_mode = phiclock->fbfrac == 0 ? PLL_MODE_INT : PLL_MODE_FRAC;
+
+	if (phiclock->ss_period == 0 && phiclock->ss_step == 0)
+		phiclock->ss_en = 0;
+
+	reg[0] = phiclock->fbint;
+	reg[1] = (phiclock->fbfrac >> 8) & 0xff;
+	reg[2] = phiclock->fbfrac & 0xff;
+	ret = regmap_bulk_write(phiclock->regmap, PHICLOCK_REG_FBINT, reg, 3);
+
+	reg[0] = phiclock->outdiv & 0xff;
+	reg[1] = (phiclock->outdiv & PHICLOCK_OUTDIV_11_8_MASK) >> 4;
+	ret = regmap_bulk_write(phiclock->regmap, PHICLOCK_REG_OUTDIV, reg, 2);
+
+	ret = regmap_write_bits(phiclock->regmap, PHICLOCK_REG_FBCNFG, PHICLOCK_FBMODE_MASK,
+				pll_mode << __ffs(PHICLOCK_FBMODE_MASK));
+
+	ret = regmap_write_bits(phiclock->regmap, PHICLOCK_REG_DOUBLER, PHICLOCK_DOUBLER_MASK,
+				phiclock->doubler << __ffs(PHICLOCK_DOUBLER_MASK));
+
+	ret = regmap_write_bits(phiclock->regmap, PHICLOCK_REG_SS_CNFG_PERIOD, PHICLOCK_SS_EN_MASK,
+				phiclock->ss_en << __ffs(PHICLOCK_SS_EN_MASK));
+
+	reg[0] = phiclock->ss_en << __ffs(PHICLOCK_SS_EN_MASK);
+	reg[0] += ((phiclock->ss_period >> 8) & PHICLOCK_SS_PERIOD_11_8_MASK);
+	reg[1] = phiclock->ss_period & 0xff;
+	ret = regmap_bulk_write(phiclock->regmap, PHICLOCK_REG_SS_CNFG_PERIOD, reg, 2);
+
+	reg[0] = (phiclock->ss_step >> 8) & 0xff;
+	reg[1] = phiclock->ss_step & 0xff;
+	ret = regmap_bulk_write(phiclock->regmap, PHICLOCK_REG_SS_STEP, reg, 2);
+
+	/* VCO calibration to apply the changes, cal starts on the 0->1 transition */
+	ret = regmap_write_bits(phiclock->regmap, PHICLOCK_REG_CALIBRATION, PHICLOCK_VCO_CAL_MASK,
+				0 << __ffs(PHICLOCK_VCO_CAL_MASK));
+	ret = regmap_write_bits(phiclock->regmap, PHICLOCK_REG_CALIBRATION, PHICLOCK_VCO_CAL_MASK,
+				1 << __ffs(PHICLOCK_VCO_CAL_MASK));
+
+	return ret;
+}
+
+static int phiclock_set_frequency(struct phiclock_data *phiclock, unsigned long frequency)
+{
+	int ret;
+
+	ret = phiclock_calc_divs(frequency, phiclock,
+				 &phiclock->doubler, &phiclock->fbint, &phiclock->fbfrac,
+				 &phiclock->outdiv, &phiclock->fout, &phiclock->fvco,
+				 &phiclock->ss_period, &phiclock->ss_step);
+	if (ret)
+		return ret;
+
+	pr_debug("doubler: %u, fbint: %u, fbfrac: %u, outdiv: %u, fvco: %u, fout: %u\n",
+		 phiclock->doubler, phiclock->fbint, phiclock->fbfrac, phiclock->outdiv,
+		 phiclock->fvco, phiclock->fout);
+
+	if (phiclock->ss_en)
+		pr_debug("ss_period: %u, ss_step: %u\n",
+			 phiclock->ss_period, phiclock->ss_step);
+
+	ret = phiclock_update_frequency(phiclock);
+
+	return ret;
+}
+
+static unsigned long phiclock_clk_recalc_rate(struct clk_hw *hw, unsigned long rate)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+	int ret;
+	u8 doubler, fbint;
+	u16 fbfrac, outdiv;
+	u32 fvco, fout;
+
+	ret = phiclock_get_divs(phiclock, &doubler, &fbint, &fbfrac, &outdiv);
+	if (ret) {
+		dev_err(&phiclock->i2c_client->dev, "recalc rate error\n");
+		return 0;
+	}
+
+	fvco = phiclock_calc_fvco(phiclock);
+	fout = fvco / outdiv;
+
+	return fout;
+}
+
+static long phiclock_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long *parent_rate)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+	int ret;
+	u8 doubler, fbint, ss_en;
+	u16 fbfrac, outdiv, ss_period, ss_step;
+	u32 fout, fvco;
+
+	if (!rate)
+		return 0;
+
+	/* Temporarily disable spread spectrum for rounding. */
+	ss_en = phiclock->ss_en;
+	phiclock->ss_en = 0;
+	ret = phiclock_calc_divs(rate, phiclock, &doubler, &fbint, &fbfrac, &outdiv, &fout, &fvco,
+				 &ss_period, &ss_step);
+	phiclock->ss_en = ss_en;
+	if (ret) {
+		dev_err(&phiclock->i2c_client->dev, "round rate error\n");
+		return 0;
+	}
+
+	return fout;
+}
+
+static int phiclock_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+
+	if (rate < PHICLOCK_FOUT_MIN || rate > PHICLOCK_FOUT_MAX) {
+		dev_err(&phiclock->i2c_client->dev, "requested frequency %lu Hz is out of range\n",
+			rate);
+		return -EINVAL;
+	}
+
+	return phiclock_set_frequency(phiclock, rate);
+}
+
+static int phiclock_clk_prepare(struct clk_hw *hw)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+	int err;
+	unsigned int reg, mask;
+
+	pr_debug("prepare %s", clk_hw_get_name(hw));
+
+	err = phiclock_get_en_reg(clk_hw->idx, &reg, &mask);
+	if (err)
+		return err;
+
+	clk_hw->enabled = 1;
+	err = regmap_update_bits(phiclock->regmap, reg, mask, mask);
+	return err;
+}
+
+static void phiclock_clk_unprepare(struct clk_hw *hw)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+	int err;
+	unsigned int reg, mask;
+
+	pr_debug("unprepare %s", clk_hw_get_name(hw));
+
+	err = phiclock_get_en_reg(clk_hw->idx, &reg, &mask);
+	if (!err) {
+		clk_hw->enabled = 0;
+		regmap_update_bits(phiclock->regmap, reg, mask, 0);
+	}
+}
+
+static int phiclock_clk_is_prepared(struct clk_hw *hw)
+{
+	struct phiclock_clk_hw *clk_hw = to_phiclock_clk(hw);
+	struct phiclock_data *phiclock = clk_hw->phiclock;
+	int err;
+	unsigned int reg, mask, val = 0;
+
+	pr_debug("is_prepared %s", clk_hw_get_name(hw));
+
+	err = phiclock_get_en_reg(clk_hw->idx, &reg, &mask);
+	if (err)
+		return err;
+
+	err = regmap_read(phiclock->regmap, reg, &val);
+	if (err)
+		return err;
+
+	return !!(val & mask);
+}
+
+static const struct i2c_device_id phiclock_i2c_id[] = {
+	{ "9fgv1006", PHICLOCK_9FGV1006 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, phiclock_i2c_id);
+
+static const struct regmap_config phiclock_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x25,
+	.cache_type = REGCACHE_RBTREE
+};
+
+struct phiclock_clk {
+	const char *name;
+	int parent_index;
+	const struct clk_ops ops;
+};
+
+static const struct phiclock_clk phiclock_clks[PHICLOCK_NUM_CLKS] = {
+	[PHICLOCK_REF0] = {
+		.name = "phiclock_ref0",
+		.parent_index = -1,
+		.ops = {
+			.prepare	= phiclock_clk_prepare,
+			.unprepare	= phiclock_clk_unprepare,
+			.is_prepared	= phiclock_clk_is_prepared,
+		},
+	},
+	[PHICLOCK_OUT] = {
+		.name = "phiclock_out",
+		.parent_index = -1,
+		.ops = {
+			.recalc_rate	= phiclock_clk_recalc_rate,
+			.round_rate	= phiclock_clk_round_rate,
+			.set_rate	= phiclock_clk_set_rate,
+		},
+	},
+	[PHICLOCK_OUT0] = {
+		.name = "phiclock_out0",
+		.parent_index = PHICLOCK_OUT,
+		.ops = {
+			.prepare	= phiclock_clk_prepare,
+			.unprepare	= phiclock_clk_unprepare,
+			.is_prepared	= phiclock_clk_is_prepared,
+		},
+	},
+	[PHICLOCK_OUT1] = {
+		.name = "phiclock_out1",
+		.parent_index = PHICLOCK_OUT,
+		.ops = {
+			.prepare	= phiclock_clk_prepare,
+			.unprepare	= phiclock_clk_unprepare,
+			.is_prepared	= phiclock_clk_is_prepared,
+		},
+	},
+};
+
+static struct clk_hw *phiclock_of_clk_get(struct of_phandle_args *clkspec, void *data)
+{
+	struct phiclock_data *driver_data = data;
+	unsigned int idx = clkspec->args[0];
+
+	return &driver_data->hw[idx].hw;
+}
+
+static int phiclock_probe(struct i2c_client *client)
+{
+	struct phiclock_data *phiclock;
+	struct device *dev = &client->dev;
+	const char *xin_clkin_name, *spread_spectrum_type_name;
+	unsigned int i;
+	u32 ss_amount = 0, ss_modulation = 0;
+	enum phiclock_ss_direction ss_direction = SS_DOWN;
+	int ret;
+
+	phiclock = devm_kzalloc(dev, sizeof(*phiclock), GFP_KERNEL);
+	if (!phiclock)
+		return -ENOMEM;
+
+	phiclock->xin_clkin_clk = devm_clk_get(dev, "xin-clkin");
+	if (IS_ERR(phiclock->xin_clkin_clk)) {
+		return dev_err_probe(dev, PTR_ERR(phiclock->xin_clkin_clk),
+				     "xin-clkin not specified\n");
+	}
+
+	xin_clkin_name = __clk_get_name(phiclock->xin_clkin_clk);
+
+	phiclock->regmap = devm_regmap_init_i2c(client, &phiclock_regmap_config);
+	if (IS_ERR(phiclock->regmap)) {
+		return dev_err_probe(dev, PTR_ERR(phiclock->regmap),
+				     "failed to initialize register map\n");
+	}
+
+	i2c_set_clientdata(client, phiclock);
+	phiclock->i2c_client = client;
+	phiclock->ss_amount = ss_amount;
+	phiclock->ss_modulation = ss_modulation;
+	phiclock->ss_direction = ss_direction;
+
+	ret = phiclock_get_defaults(phiclock);
+	if (ret) {
+		dev_err(dev, "error getting defaults\n");
+		return ret;
+	}
+
+	for (i = 0; i < PHICLOCK_NUM_CLKS; i++) {
+		int parent_index = phiclock_clks[i].parent_index;
+		const char *name;
+
+		if (of_property_read_string_index(dev->of_node,
+						  "clock-output-names", i, &name) == 0) {
+			phiclock->hw[i].init.name = name;
+		} else {
+			phiclock->hw[i].init.name = phiclock_clks[i].name;
+		}
+
+		phiclock->hw[i].idx = i;
+		phiclock->hw[i].init.ops = &phiclock_clks[i].ops;
+		phiclock->hw[i].init.num_parents = 1;
+		phiclock->hw[i].init.flags = 0;
+
+		if (parent_index > 0) {
+			phiclock->hw[i].init.parent_names = &phiclock->hw[parent_index].init.name;
+			phiclock->hw[i].init.flags |= CLK_SET_RATE_PARENT;
+		} else {
+			phiclock->hw[i].init.parent_names = &xin_clkin_name;
+		}
+
+		phiclock->hw[i].hw.init = &phiclock->hw[i].init;
+		phiclock->hw[i].phiclock = phiclock;
+
+		ret = devm_clk_hw_register(dev, &phiclock->hw[i].hw);
+		if (ret < 0) {
+			return dev_err_probe(dev, ret, "failed to register %s clock\n",
+					     phiclock->hw[i].init.name);
+		}
+	}
+
+	if (of_property_read_u32(dev->of_node, "renesas,ss-amount-percent", &ss_amount) == 0)
+		phiclock->ss_amount = ss_amount;
+
+	if (of_property_read_u32(dev->of_node, "renesas,ss-modulation-hz", &ss_modulation) == 0)
+		phiclock->ss_modulation = ss_modulation;
+
+	if (of_property_read_string(dev->of_node, "renesas,ss-direction",
+				    &spread_spectrum_type_name) == 0) {
+		if (strcmp(spread_spectrum_type_name, "center") == 0)
+			phiclock->ss_direction = SS_CENTER;
+		else
+			phiclock->ss_direction = SS_DOWN;
+	}
+
+	ret = devm_of_clk_add_hw_provider(dev, phiclock_of_clk_get, phiclock);
+	if (ret) {
+		dev_err(dev, "unable to add clk provider\n");
+		return ret;
+	}
+
+	dev_info(dev, "registered, current frequency %u Hz\n", phiclock->fout);
+
+	return ret;
+}
+
+static void phiclock_remove(struct i2c_client *client)
+{
+	of_clk_del_provider(client->dev.of_node);
+}
+
+static const struct of_device_id phiclock_of_match[] = {
+	{ .compatible = "renesas,9fgv1006" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, phiclock_of_match);
+
+static struct i2c_driver phiclock_i2c_driver = {
+	.driver = {
+		.name = "phiclock",
+		.of_match_table = phiclock_of_match,
+	},
+	.probe_new = phiclock_probe,
+	.remove = phiclock_remove,
+	.id_table = phiclock_i2c_id,
+};
+module_i2c_driver(phiclock_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alex Helms <alexander.helms.jy@renesas.com");
+MODULE_DESCRIPTION("Renesas PhiClock Clock Generator Driver");