[PATCH 2/6] clk: at91: add audio pll clock driver
Alexandre Belloni
alexandre.belloni at free-electrons.com
Fri Jun 23 08:39:58 PDT 2017
Hi,
On 23/06/2017 at 11:00:55 +0200, Quentin Schulz wrote:
> From: Nicolas Ferre <nicolas.ferre at atmel.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 at atmel.com>
> Signed-off-by: Quentin Schulz <quentin.schulz at free-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 +-
This should definitively go in a separate patch.
> 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 at atmel.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 at atmel.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 at atmel.com>,
> + * Nicolas Ferre <nicolas.ferre at atmel.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
>
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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