Date:   Fri, 23 Jun 2017 11:00:55 +0200
From:   Quentin Schulz <quentin.schulz@...e-electrons.com>
To:     mturquette@...libre.com, sboyd@...eaurora.org, robh+dt@...nel.org,
        mark.rutland@....com, nicolas.ferre@...rochip.com,
        alexandre.belloni@...e-electrons.com, linux@...linux.org.uk,
        boris.brezillon@...e-electrons.com, lgirdwood@...il.com,
        broonie@...nel.org, perex@...ex.cz, tiwai@...e.com
Cc:     Nicolas Ferre <nicolas.ferre@...el.com>, linux-clk@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, alsa-devel@...a-project.org,
        thomas.petazzoni@...e-electrons.com,
        Quentin Schulz <quentin.schulz@...e-electrons.com>
Subject: [PATCH 2/6] clk: at91: add audio pll clock driver

From: Nicolas Ferre <nicolas.ferre@...el.com>

This new clock driver set allows to have a fractional divided clock that
would generate a precise clock particularly suitable for audio
applications.

The main audio pll clock has two children clocks: one that is connected
to the PMC, the other that can directly drive a pad. As these two routes
have different enable bits and different dividers and divider formula,
they are handled by two different drivers. Each of them could modify the
rate of the main audio pll parent.
The main audio pll clock can output 620MHz to 700MHz.

Signed-off-by: Nicolas Ferre <nicolas.ferre@...el.com>
Signed-off-by: Quentin Schulz <quentin.schulz@...e-electrons.com>
---
 .../devicetree/bindings/clock/at91-clock.txt       |  10 +
 arch/arm/mach-at91/Kconfig                         |   4 +
 drivers/clk/at91/Makefile                          |   2 +
 drivers/clk/at91/clk-audio-pll-pad.c               | 204 ++++++++++++++++++
 drivers/clk/at91/clk-audio-pll-pmc.c               | 175 +++++++++++++++
 drivers/clk/at91/clk-audio-pll.c                   | 237 +++++++++++++++++++++
 include/linux/clk/at91_pmc.h                       |  25 +++
 sound/soc/atmel/atmel-classd.c                     |  20 +-
 8 files changed, 658 insertions(+), 19 deletions(-)
 create mode 100644 drivers/clk/at91/clk-audio-pll-pad.c
 create mode 100644 drivers/clk/at91/clk-audio-pll-pmc.c
 create mode 100644 drivers/clk/at91/clk-audio-pll.c

diff --git a/Documentation/devicetree/bindings/clock/at91-clock.txt b/Documentation/devicetree/bindings/clock/at91-clock.txt
index 5f3ad65daf69..51c259a92d02 100644
--- a/Documentation/devicetree/bindings/clock/at91-clock.txt
+++ b/Documentation/devicetree/bindings/clock/at91-clock.txt
@@ -81,6 +81,16 @@ Required properties:
 	"atmel,sama5d2-clk-generated":
 		at91 generated clock
 
+	"atmel,sama5d2-clk-audio-pll-frac":
+		at91 audio fractional pll
+
+	"atmel,sama5d2-clk-audio-pll-pad":
+		at91 audio pll CLK_AUDIO output pin
+
+	"atmel,sama5d2-clk-audio-pll-pmc"
+		at91 audio pll output on AUDIOPLLCLK that feeds the PMC
+		and can be used by peripheral clock or generic clock
+
 Required properties for SCKC node:
 - reg : defines the IO memory reserved for the SCKC.
 - #size-cells : shall be 0 (reg is used to encode clk id).
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index d735e5fc4772..9ae14d59a9ce 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -26,6 +26,7 @@ config SOC_SAMA5D2
 	select HAVE_AT91_USB_CLK
 	select HAVE_AT91_H32MX
 	select HAVE_AT91_GENERATED_CLK
+	select HAVE_AT91_AUDIO_PLL
 	select PINCTRL_AT91PIO4
 	help
 	  Select this if ou are using one of Atmel's SAMA5D2 family SoC.
@@ -125,6 +126,9 @@ config HAVE_AT91_H32MX
 config HAVE_AT91_GENERATED_CLK
 	bool
 
+config HAVE_AT91_AUDIO_PLL
+	bool
+
 config SOC_SAM_V4_V5
 	bool
 
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 13e67bd35cff..c9353d17763a 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -6,6 +6,8 @@ obj-y += pmc.o sckc.o
 obj-y += clk-slow.o clk-main.o clk-pll.o clk-plldiv.o clk-master.o
 obj-y += clk-system.o clk-peripheral.o clk-programmable.o
 
+obj-$(CONFIG_HAVE_AT91_AUDIO_PLL)	+= clk-audio-pll.o
+obj-$(CONFIG_HAVE_AT91_AUDIO_PLL)	+= clk-audio-pll-pmc.o clk-audio-pll-pad.o
 obj-$(CONFIG_HAVE_AT91_UTMI)		+= clk-utmi.o
 obj-$(CONFIG_HAVE_AT91_USB_CLK)		+= clk-usb.o
 obj-$(CONFIG_HAVE_AT91_SMD)		+= clk-smd.o
diff --git a/drivers/clk/at91/clk-audio-pll-pad.c b/drivers/clk/at91/clk-audio-pll-pad.c
new file mode 100644
index 000000000000..a60ce47b82c6
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll-pad.c
@@ -0,0 +1,204 @@
+/*
+ *  Copyright (C) 2016 Atmel Corporation,
+ *                     Nicolas Ferre <nicolas.ferre@...el.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+/*
+ * DOC: PAD output for fractional PLL clock for audio
+ *
+ * Traits of this clock:
+ * enable - clk_enable writes divisors and enables PAD output
+ * rate - rate is adjustable.
+ *        clk->rate = parent->rate / (qdaudio * div))
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+#define AUDIO_PLL_QDPAD(qd, div)	((AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV(qd) & \
+					  AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_MASK) | \
+					 (AT91_PMC_AUDIO_PLL_QDPAD_DIV(div) & \
+					  AT91_PMC_AUDIO_PLL_QDPAD_DIV_MASK))
+
+struct clk_audio_pad {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	u8 qdaudio;
+	u8 div;
+};
+
+#define to_clk_audio_pad(hw) container_of(hw, struct clk_audio_pad, hw)
+
+static int clk_audio_pll_pad_enable(struct clk_hw *hw)
+{
+	struct clk_audio_pad *apad_ck = to_clk_audio_pad(hw);
+
+	regmap_update_bits(apad_ck->regmap, AT91_PMC_AUDIO_PLL1,
+			   AT91_PMC_AUDIO_PLL_QDPAD_MASK,
+			   AUDIO_PLL_QDPAD(apad_ck->qdaudio, apad_ck->div));
+	regmap_update_bits(apad_ck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PADEN, AT91_PMC_AUDIO_PLL_PADEN);
+
+	return 0;
+}
+
+static void clk_audio_pll_pad_disable(struct clk_hw *hw)
+{
+	struct clk_audio_pad *apad_ck = to_clk_audio_pad(hw);
+
+	regmap_update_bits(apad_ck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PADEN, 0);
+}
+
+static unsigned long clk_audio_pll_pad_recalc_rate(struct clk_hw *hw,
+						   unsigned long parent_rate)
+{
+	struct clk_audio_pad *apad_ck = to_clk_audio_pad(hw);
+	unsigned long apad_rate = 0;
+
+	if (apad_ck->qdaudio && apad_ck->div)
+		apad_rate = parent_rate / (apad_ck->qdaudio * apad_ck->div);
+
+	pr_debug("A PLL/PAD: %s, apad_rate = %lu (div = %u, qdaudio = %u)\n",
+		 __func__, apad_rate, apad_ck->div, apad_ck->qdaudio);
+
+	return apad_rate;
+}
+
+static long clk_audio_pll_pad_round_rate(struct clk_hw *hw, unsigned long rate,
+					 unsigned long *parent_rate)
+{
+	struct clk_hw *pclk = clk_hw_get_parent(hw);
+	long best_rate = -EINVAL;
+	unsigned long best_parent_rate;
+	unsigned long tmp_qd;
+	u32 div;
+	long tmp_rate;
+	int tmp_diff;
+	int best_diff = -1;
+
+	pr_debug("A PLL/PAD: %s, rate = %lu (parent_rate = %lu)\n", __func__,
+		 rate, *parent_rate);
+
+	/*
+	 * Rate divisor is actually made of two different divisors, multiplied
+	 * between themselves before dividing the rate.
+	 * tmp_qd goes from 1 to 31 and div is either 2 or 3.
+	 * In order to avoid testing twice the rate divisor (e.g. divisor 12 can
+	 * be found with (tmp_qd, div) = (2, 6) or (3, 4)), we remove any loop
+	 * for a rate divisor when div is 2 and tmp_qd is a multiple of 3.
+	 * We cannot inverse it (condition div is 3 and tmp_qd is even) or we
+	 * would miss some rate divisor that aren't reachable with div being 2
+	 * (e.g. rate divisor 90 is made with div = 3 and tmp_qd = 30, thus
+	 * tmp_qd is even so we skip it because we think div 2 could make this
+	 * rate divisor which isn't possible since tmp_qd has to be <= 31).
+	 */
+	for (tmp_qd = 1; tmp_qd < AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_MAX; tmp_qd++)
+		for (div = 2; div <= 3; div++) {
+			if (div == 2 && tmp_qd % 3 == 0)
+				continue;
+
+			best_parent_rate = clk_hw_round_rate(pclk,
+							rate * tmp_qd * div);
+			tmp_rate = best_parent_rate / (div * tmp_qd);
+			tmp_diff = abs(rate - tmp_rate);
+
+			if (best_diff < 0 || best_diff > tmp_diff) {
+				*parent_rate = best_parent_rate;
+				best_rate = tmp_rate;
+				best_diff = tmp_diff;
+			}
+		}
+
+	pr_debug("A PLL/PAD: %s, best_rate = %ld, best_parent_rate = %lu\n",
+		 __func__, best_rate, best_parent_rate);
+
+	return best_rate;
+}
+
+static int clk_audio_pll_pad_set_rate(struct clk_hw *hw, unsigned long rate,
+				      unsigned long parent_rate)
+{
+	struct clk_audio_pad *apad_ck = to_clk_audio_pad(hw);
+	u8 tmp_div;
+
+	pr_debug("A PLL/PAD: %s, rate = %lu (parent_rate = %lu)\n", __func__,
+		 rate, parent_rate);
+
+	if (!rate)
+		return -EINVAL;
+
+	tmp_div = parent_rate / rate;
+	if (tmp_div % 3 == 0) {
+		apad_ck->qdaudio = tmp_div / 3;
+		apad_ck->div = 3;
+	} else {
+		apad_ck->qdaudio = tmp_div / 2;
+		apad_ck->div = 2;
+	}
+
+	return 0;
+}
+
+static const struct clk_ops audio_pll_pad_ops = {
+	.enable = clk_audio_pll_pad_enable,
+	.disable = clk_audio_pll_pad_disable,
+	.recalc_rate = clk_audio_pll_pad_recalc_rate,
+	.round_rate = clk_audio_pll_pad_round_rate,
+	.set_rate = clk_audio_pll_pad_set_rate,
+};
+
+static void __init of_sama5d2_clk_audio_pll_pad_setup(struct device_node *np)
+{
+	struct clk_audio_pad *apad_ck;
+	struct clk_init_data init;
+	struct regmap *regmap;
+	const char *parent_name;
+	const char *name = np->name;
+	int ret;
+
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	of_property_read_string(np, "clock-output-names", &name);
+
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap))
+		return;
+
+	apad_ck = kzalloc(sizeof(*apad_ck), GFP_KERNEL);
+	if (!apad_ck)
+		return;
+
+	init.name = name;
+	init.ops = &audio_pll_pad_ops;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = 1;
+	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+		CLK_SET_RATE_PARENT;
+
+	apad_ck->hw.init = &init;
+	apad_ck->regmap = regmap;
+
+	ret = clk_hw_register(NULL, &apad_ck->hw);
+	if (ret)
+		kfree(apad_ck);
+	else
+		of_clk_add_hw_provider(np, of_clk_hw_simple_get, &apad_ck->hw);
+}
+
+CLK_OF_DECLARE(of_sama5d2_clk_audio_pll_pad_setup,
+	       "atmel,sama5d2-clk-audio-pll-pad",
+	       of_sama5d2_clk_audio_pll_pad_setup);
diff --git a/drivers/clk/at91/clk-audio-pll-pmc.c b/drivers/clk/at91/clk-audio-pll-pmc.c
new file mode 100644
index 000000000000..208d0b59eb4e
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll-pmc.c
@@ -0,0 +1,175 @@
+/*
+ *  Copyright (C) 2016 Atmel Corporation,
+ *                     Nicolas Ferre <nicolas.ferre@...el.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+/*
+ * DOC: PMC output for fractional PLL clock for audio
+ *
+ * Traits of this clock:
+ * enable - clk_enable writes qdpmc, and enables PMC output
+ * rate - rate is adjustable.
+ *        clk->rate = parent->rate / (qdpmc + 1)
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+#define AUDIO_PLL_FOUT_MIN		620000000
+#define AUDIO_PLL_FOUT_MAX		700000000
+#define AUDIO_PLL_REFERENCE_FOUT	660000000
+#define AUDIO_PLL_QDPMC_MAX		(AT91_PMC_AUDIO_PLL_QDPMC_MASK >> \
+						AT91_PMC_AUDIO_PLL_QDPMC_OFFSET)
+struct clk_audio_pmc {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	u8 qdpmc;
+};
+
+#define to_clk_audio_pmc(hw) container_of(hw, struct clk_audio_pmc, hw)
+
+static int clk_audio_pll_pmc_enable(struct clk_hw *hw)
+{
+	struct clk_audio_pmc *apmc_ck = to_clk_audio_pmc(hw);
+
+	regmap_update_bits(apmc_ck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PMCEN |
+			   AT91_PMC_AUDIO_PLL_QDPMC_MASK,
+			   AT91_PMC_AUDIO_PLL_PMCEN |
+			   AT91_PMC_AUDIO_PLL_QDPMC(apmc_ck->qdpmc));
+	return 0;
+}
+
+static void clk_audio_pll_pmc_disable(struct clk_hw *hw)
+{
+	struct clk_audio_pmc *apmc_ck = to_clk_audio_pmc(hw);
+
+	regmap_update_bits(apmc_ck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PMCEN, 0);
+}
+
+static unsigned long clk_audio_pll_pmc_recalc_rate(struct clk_hw *hw,
+						   unsigned long parent_rate)
+{
+	struct clk_audio_pmc *apmc_ck = to_clk_audio_pmc(hw);
+	unsigned long apmc_rate = 0;
+
+	apmc_rate = parent_rate / (apmc_ck->qdpmc + 1);
+
+	pr_debug("A PLL/PMC: %s, apmc_rate = %lu (qdpmc = %u)\n", __func__,
+		 apmc_rate, apmc_ck->qdpmc);
+
+	return apmc_rate;
+}
+
+static long clk_audio_pll_pmc_round_rate(struct clk_hw *hw, unsigned long rate,
+					 unsigned long *parent_rate)
+{
+	struct clk_hw *pclk = clk_hw_get_parent(hw);
+	long best_rate = -EINVAL;
+	unsigned long best_parent_rate = 0;
+	u32 tmp_qd = 0, div;
+	long tmp_rate;
+	int tmp_diff;
+	int best_diff = -1;
+
+	pr_debug("A PLL/PMC: %s, rate = %lu (parent_rate = %lu)\n", __func__,
+		 rate, *parent_rate);
+
+	for (div = 1; div <= AUDIO_PLL_QDPMC_MAX; div++) {
+		best_parent_rate = clk_round_rate(pclk->clk, rate * div);
+		tmp_rate = best_parent_rate / div;
+		tmp_diff = abs(rate - tmp_rate);
+
+		if (best_diff < 0 || best_diff > tmp_diff) {
+			*parent_rate = best_parent_rate;
+			best_rate = tmp_rate;
+			best_diff = tmp_diff;
+			tmp_qd = div;
+		}
+	}
+
+	pr_debug("A PLL/PMC: %s, best_rate = %ld, best_parent_rate = %lu (qd = %d)\n",
+		 __func__, best_rate, *parent_rate, tmp_qd - 1);
+
+	return best_rate;
+}
+
+static int clk_audio_pll_pmc_set_rate(struct clk_hw *hw, unsigned long rate,
+				      unsigned long parent_rate)
+{
+	struct clk_audio_pmc *apmc_ck = to_clk_audio_pmc(hw);
+
+	if (!rate)
+		return -EINVAL;
+
+	pr_debug("A PLL/PMC: %s, rate = %lu (parent_rate = %lu)\n", __func__,
+		 rate, parent_rate);
+
+	apmc_ck->qdpmc = parent_rate / rate - 1;
+
+	return 0;
+}
+
+static const struct clk_ops audio_pll_pmc_ops = {
+	.enable = clk_audio_pll_pmc_enable,
+	.disable = clk_audio_pll_pmc_disable,
+	.recalc_rate = clk_audio_pll_pmc_recalc_rate,
+	.round_rate = clk_audio_pll_pmc_round_rate,
+	.set_rate = clk_audio_pll_pmc_set_rate,
+};
+
+static void __init of_sama5d2_clk_audio_pll_pmc_setup(struct device_node *np)
+{
+	struct clk_audio_pmc *apmc_ck;
+	struct clk_init_data init;
+	struct regmap *regmap;
+	const char *parent_name;
+	const char *name = np->name;
+	int ret;
+
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	of_property_read_string(np, "clock-output-names", &name);
+
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap))
+		return;
+
+	apmc_ck = kzalloc(sizeof(*apmc_ck), GFP_KERNEL);
+	if (!apmc_ck)
+		return;
+
+	init.name = name;
+	init.ops = &audio_pll_pmc_ops;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = 1;
+	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+		CLK_SET_RATE_PARENT;
+
+	apmc_ck->hw.init = &init;
+	apmc_ck->regmap = regmap;
+
+	ret = clk_hw_register(NULL, &apmc_ck->hw);
+	if (ret)
+		kfree(apmc_ck);
+	else
+		of_clk_add_hw_provider(np, of_clk_hw_simple_get, &apmc_ck->hw);
+}
+
+CLK_OF_DECLARE(of_sama5d2_clk_audio_pll_pmc_setup,
+	       "atmel,sama5d2-clk-audio-pll-pmc",
+	       of_sama5d2_clk_audio_pll_pmc_setup);
diff --git a/drivers/clk/at91/clk-audio-pll.c b/drivers/clk/at91/clk-audio-pll.c
new file mode 100644
index 000000000000..ad8c8827681e
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll.c
@@ -0,0 +1,237 @@
+/*
+ *  Copyright (C) 2016 Atmel Corporation,
+ *		       Songjun Wu <songjun.wu@...el.com>,
+ *                     Nicolas Ferre <nicolas.ferre@...el.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+/*
+ * DOC: Fractional PLL clock for audio
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare puts audio PLL in reset state
+ * enable - clk_enable writes nd, fracr parameters and enables PLL
+ * rate - rate is adjustable.
+ *        clk->rate = parent->rate * ((nd + 1) + (fracr / 2^22))
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+#define AUDIO_PLL_DIV_FRAC	BIT(22)
+#define AUDIO_PLL_ND_MAX	(AT91_PMC_AUDIO_PLL_ND_MASK >> \
+					AT91_PMC_AUDIO_PLL_ND_OFFSET)
+
+#define AUDIO_PLL_FOUT_MIN	620000000
+#define AUDIO_PLL_FOUT_MAX	700000000
+
+struct clk_audio_frac {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	u32 fracr;
+	u8 nd;
+};
+
+#define to_clk_audio_frac(hw) container_of(hw, struct clk_audio_frac, hw)
+
+static int clk_audio_pll_enable(struct clk_hw *hw)
+{
+	struct clk_audio_frac *fck = to_clk_audio_frac(hw);
+
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_RESETN, 0);
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_RESETN,
+			   AT91_PMC_AUDIO_PLL_RESETN);
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL1,
+			   AT91_PMC_AUDIO_PLL_FRACR_MASK, fck->fracr);
+
+	/*
+	 * reset and enable have to be done in 2 separated writes
+	 * for AT91_PMC_AUDIO_PLL0
+	 */
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PLLEN |
+			   AT91_PMC_AUDIO_PLL_ND_MASK,
+			   AT91_PMC_AUDIO_PLL_PLLEN |
+			   AT91_PMC_AUDIO_PLL_ND(fck->nd));
+
+	return 0;
+}
+
+static void clk_audio_pll_disable(struct clk_hw *hw)
+{
+	struct clk_audio_frac *fck = to_clk_audio_frac(hw);
+
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_PLLEN, 0);
+	/* do it in 2 separated writes */
+	regmap_update_bits(fck->regmap, AT91_PMC_AUDIO_PLL0,
+			   AT91_PMC_AUDIO_PLL_RESETN, 0);
+}
+
+static unsigned long clk_audio_pll_fout(unsigned long parent_rate,
+					unsigned long nd, unsigned long fracr)
+{
+	unsigned long long fr = (unsigned long long)parent_rate *
+						(unsigned long long)fracr;
+
+	pr_debug("A PLL: %s, fr = %llu\n", __func__, fr);
+
+	fr = DIV_ROUND_CLOSEST_ULL(fr, AUDIO_PLL_DIV_FRAC);
+
+	pr_debug("A PLL: %s, fr = %llu\n", __func__, fr);
+
+	return parent_rate * (nd + 1) + fr;
+}
+
+static unsigned long clk_audio_pll_recalc_rate(struct clk_hw *hw,
+					       unsigned long parent_rate)
+{
+	struct clk_audio_frac *fck = to_clk_audio_frac(hw);
+	unsigned long fout;
+
+	fout = clk_audio_pll_fout(parent_rate, fck->nd, fck->fracr);
+
+	pr_debug("A PLL: %s, fout = %lu (nd = %u, fracr = %lu)\n", __func__,
+		 fout, fck->nd, (unsigned long)fck->fracr);
+
+	return fout;
+}
+
+static int clk_audio_pll_compute_frac(unsigned long rate,
+				      unsigned long parent_rate,
+				      unsigned long *nd, unsigned long *fracr)
+{
+	unsigned long long tmp, rem;
+
+	if (!rate)
+		return -EINVAL;
+
+	tmp = rate;
+	rem = do_div(tmp, parent_rate);
+	if (!tmp || tmp >= AUDIO_PLL_ND_MAX)
+		return -EINVAL;
+
+	*nd = tmp - 1;
+
+	tmp = rem * AUDIO_PLL_DIV_FRAC;
+	tmp = DIV_ROUND_CLOSEST_ULL(tmp, parent_rate);
+	if (tmp > AT91_PMC_AUDIO_PLL_FRACR_MASK)
+		return -EINVAL;
+
+	/* we can cast here as we verified the bounds just above */
+	*fracr = (unsigned long)tmp;
+
+	return 0;
+}
+
+static long clk_audio_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+				     unsigned long *parent_rate)
+{
+	long best_rate = -EINVAL;
+	unsigned long fracr, nd;
+	int ret;
+
+	pr_debug("A PLL: %s, rate = %lu (parent_rate = %lu)\n", __func__, rate,
+		 *parent_rate);
+
+	if (rate < AUDIO_PLL_FOUT_MIN)
+		rate = AUDIO_PLL_FOUT_MIN;
+	else if (rate > AUDIO_PLL_FOUT_MAX)
+		rate = AUDIO_PLL_FOUT_MAX;
+
+	ret = clk_audio_pll_compute_frac(rate, *parent_rate, &nd, &fracr);
+	if (ret)
+		return ret;
+
+	best_rate = clk_audio_pll_fout(*parent_rate, nd, fracr);
+
+	pr_debug("A PLL: %s, best_rate = %lu (nd = %lu, fracr = %lu)\n",
+		 __func__, best_rate, nd, fracr);
+
+	return best_rate;
+}
+
+static int clk_audio_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+				  unsigned long parent_rate)
+{
+	struct clk_audio_frac *fck = to_clk_audio_frac(hw);
+	unsigned long fracr, nd;
+	int ret;
+
+	pr_debug("A PLL: %s, rate = %lu (parent_rate = %lu)\n", __func__, rate,
+		 parent_rate);
+
+	if (rate < AUDIO_PLL_FOUT_MIN || rate > AUDIO_PLL_FOUT_MAX)
+		return -EINVAL;
+
+	ret = clk_audio_pll_compute_frac(rate, parent_rate, &nd, &fracr);
+	if (ret)
+		return ret;
+
+	fck->nd = nd;
+	fck->fracr = fracr;
+
+	return 0;
+}
+
+static const struct clk_ops audio_pll_ops = {
+	.enable = clk_audio_pll_enable,
+	.disable = clk_audio_pll_disable,
+	.recalc_rate = clk_audio_pll_recalc_rate,
+	.round_rate = clk_audio_pll_round_rate,
+	.set_rate = clk_audio_pll_set_rate,
+};
+
+static void __init of_sama5d2_clk_audio_pll_setup(struct device_node *np)
+{
+	struct clk_audio_frac *fck;
+	struct clk_init_data init;
+	struct regmap *regmap;
+	const char *parent_name;
+	const char *name = np->name;
+	int ret;
+
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	of_property_read_string(np, "clock-output-names", &name);
+
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap))
+		return;
+
+	fck = kzalloc(sizeof(*fck), GFP_KERNEL);
+	if (!fck)
+		return;
+
+	init.name = name;
+	init.ops = &audio_pll_ops;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = 1;
+	init.flags = CLK_SET_RATE_GATE;
+
+	fck->hw.init = &init;
+	fck->regmap = regmap;
+
+	ret = clk_hw_register(NULL, &fck->hw);
+	if (ret)
+		kfree(fck);
+	else
+		of_clk_add_hw_provider(np, of_clk_hw_simple_get, &fck->hw);
+}
+
+CLK_OF_DECLARE(of_sama5d2_clk_audio_pll_setup,
+	       "atmel,sama5d2-clk-audio-pll-frac",
+	       of_sama5d2_clk_audio_pll_setup);
diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
index 17f413bbbedf..6aca5ce8a99a 100644
--- a/include/linux/clk/at91_pmc.h
+++ b/include/linux/clk/at91_pmc.h
@@ -185,4 +185,29 @@
 #define		AT91_PMC_PCR_EN			(0x1  <<  28)				/* Enable */
 #define		AT91_PMC_PCR_GCKEN		(0x1  <<  29)				/* GCK Enable */
 
+#define AT91_PMC_AUDIO_PLL0	0x14c
+#define		AT91_PMC_AUDIO_PLL_PLLEN	(1  <<  0)
+#define		AT91_PMC_AUDIO_PLL_PADEN	(1  <<  1)
+#define		AT91_PMC_AUDIO_PLL_PMCEN	(1  <<  2)
+#define		AT91_PMC_AUDIO_PLL_RESETN	(1  <<  3)
+#define		AT91_PMC_AUDIO_PLL_ND_OFFSET	8
+#define		AT91_PMC_AUDIO_PLL_ND_MASK	(0x7f << AT91_PMC_AUDIO_PLL_ND_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_ND(n)	((n)  << AT91_PMC_AUDIO_PLL_ND_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPMC_OFFSET	16
+#define		AT91_PMC_AUDIO_PLL_QDPMC_MASK	(0x7f << AT91_PMC_AUDIO_PLL_QDPMC_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPMC(n)	((n)  << AT91_PMC_AUDIO_PLL_QDPMC_OFFSET)
+
+#define AT91_PMC_AUDIO_PLL1	0x150
+#define		AT91_PMC_AUDIO_PLL_FRACR_MASK		0x3fffff
+#define		AT91_PMC_AUDIO_PLL_QDPAD_OFFSET		24
+#define		AT91_PMC_AUDIO_PLL_QDPAD_MASK		(0x7f << AT91_PMC_AUDIO_PLL_QDPAD_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPAD(n)		((n)  << AT91_PMC_AUDIO_PLL_QDPAD_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPAD_DIV_OFFSET	AT91_PMC_AUDIO_PLL_QDPAD_OFFSET
+#define		AT91_PMC_AUDIO_PLL_QDPAD_DIV_MASK	(0x3  << AT91_PMC_AUDIO_PLL_QDPAD_DIV_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPAD_DIV(n)		((n)  << AT91_PMC_AUDIO_PLL_QDPAD_DIV_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_OFFSET	26
+#define		AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_MAX	0x1f
+#define		AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_MASK	(AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_MAX << AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_OFFSET)
+#define		AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV(n)	((n)  << AT91_PMC_AUDIO_PLL_QDPAD_EXTDIV_OFFSET)
+
 #endif
diff --git a/sound/soc/atmel/atmel-classd.c b/sound/soc/atmel/atmel-classd.c
index b7ef8c59b49a..05bf5004fecc 100644
--- a/sound/soc/atmel/atmel-classd.c
+++ b/sound/soc/atmel/atmel-classd.c
@@ -32,7 +32,6 @@ struct atmel_classd {
 	struct regmap *regmap;
 	struct clk *pclk;
 	struct clk *gclk;
-	struct clk *aclk;
 	int irq;
 	const struct atmel_classd_pdata *pdata;
 };
@@ -332,10 +331,6 @@ static int atmel_classd_codec_dai_startup(struct snd_pcm_substream *substream,
 	struct atmel_classd *dd = snd_soc_card_get_drvdata(rtd->card);
 	int ret;
 
-	ret = clk_prepare_enable(dd->aclk);
-	if (ret)
-		return ret;
-
 	return clk_prepare_enable(dd->gclk);
 }
 
@@ -414,9 +409,8 @@ atmel_classd_codec_dai_hw_params(struct snd_pcm_substream *substream,
 		sample_rates[best].rate, sample_rates[best].aclk_rate);
 
 	clk_disable_unprepare(dd->gclk);
-	clk_disable_unprepare(dd->aclk);
 
-	ret = clk_set_rate(dd->aclk, sample_rates[best].aclk_rate);
+	ret = clk_set_rate(dd->gclk, sample_rates[best].aclk_rate);
 	if (ret)
 		return ret;
 
@@ -426,10 +420,6 @@ atmel_classd_codec_dai_hw_params(struct snd_pcm_substream *substream,
 
 	snd_soc_update_bits(codec, CLASSD_INTPMR, mask, val);
 
-	ret = clk_prepare_enable(dd->aclk);
-	if (ret)
-		return ret;
-
 	return clk_prepare_enable(dd->gclk);
 }
 
@@ -441,7 +431,6 @@ atmel_classd_codec_dai_shutdown(struct snd_pcm_substream *substream,
 	struct atmel_classd *dd = snd_soc_card_get_drvdata(rtd->card);
 
 	clk_disable_unprepare(dd->gclk);
-	clk_disable_unprepare(dd->aclk);
 }
 
 static int atmel_classd_codec_dai_prepare(struct snd_pcm_substream *substream,
@@ -596,13 +585,6 @@ static int atmel_classd_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	dd->aclk = devm_clk_get(dev, "aclk");
-	if (IS_ERR(dd->aclk)) {
-		ret = PTR_ERR(dd->aclk);
-		dev_err(dev, "failed to get audio clock: %d\n", ret);
-		return ret;
-	}
-
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	io_base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(io_base)) {
-- 
2.11.0

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