[PATCH v3 3/9] clk: at91: add audio pll clock drivers
Quentin Schulz
quentin.schulz at free-electrons.com
Thu Jul 13 00:49:21 PDT 2017
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 formulas,
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 at atmel.com>
Signed-off-by: Quentin Schulz <quentin.schulz at free-electrons.com>
---
v2:
- split DT binding in a different patch,
- removed unused AUDIO_PLL_*FOUT* defines from clk-audio-pll-pmc,
- split classD modifications in a different patch,
arch/arm/mach-at91/Kconfig | 4 +
drivers/clk/at91/Makefile | 2 +
drivers/clk/at91/clk-audio-pll-pad.c | 206 ++++++++++++++++++++++++++++++
drivers/clk/at91/clk-audio-pll-pmc.c | 174 +++++++++++++++++++++++++
drivers/clk/at91/clk-audio-pll.c | 239 +++++++++++++++++++++++++++++++++++
include/linux/clk/at91_pmc.h | 25 ++++
6 files changed, 650 insertions(+)
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/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..10dd6d625696
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll-pad.c
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation,
+ * Nicolas Ferre <nicolas.ferre at atmel.com>
+ * Copyright (C) 2017 Free Electrons,
+ * Quentin Schulz <quentin.schulz at free-electrons.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..7b0847ed7a4b
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll-pmc.c
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation,
+ * Nicolas Ferre <nicolas.ferre at atmel.com>
+ * Copyright (C) 2017 Free Electrons,
+ * Quentin Schulz <quentin.schulz at free-electrons.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_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..efc2cb58da85
--- /dev/null
+++ b/drivers/clk/at91/clk-audio-pll.c
@@ -0,0 +1,239 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation,
+ * Songjun Wu <songjun.wu at atmel.com>,
+ * Nicolas Ferre <nicolas.ferre at atmel.com>
+ * Copyright (C) 2017 Free Electrons,
+ * Quentin Schulz <quentin.schulz at free-electrons.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
--
2.11.0
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