[alsa-devel] [PATCH v5 2/2] mfd: Add Samsung Exynos Low Power Audio Subsystem driver
Lee Jones
lee.jones at linaro.org
Tue Aug 9 17:29:21 CEST 2016
On Tue, 09 Aug 2016, Sylwester Nawrocki wrote:
> This patch adds common driver for the Top block of the Samsung Exynos SoC
> Low Power Audio Subsystem. This is a minimal driver which prepares resources
> for IP blocks like I2S, audio DMA and UART and exposes a regmap for the Top
> block registers. Also system power ops are added to ensure the Audio Subsystem
> is operational after system suspend/resume cycle.
>
> Signed-off-by: Inha Song <ideal.song at samsung.com>
> Signed-off-by: Beomho Seo <beomho.seo at samsung.com>
> Signed-off-by: Sylwester Nawrocki <s.nawrocki at samsung.com>
> ---
>
> Changes since v4:
I only just reviewed v4.
>
> Changes since v3:
> - moved from sound/soc/samsung and rewritten as a MFD driver,
> - PMU register definitions moved to include/linux/mfd/syscon/exynos5-pmu.h,
> - added regmap for LPASS Top SFR region,
> - cleaned up register bit field defintions.
>
> Changes since v2:
> - move misplaced SND_SAMSUNG_AUDSS Kconfig symbol addition
> to this patch.
> ---
> drivers/mfd/Kconfig | 8 ++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/exynos-lpass.c | 185 +++++++++++++++++++++++++++++++++
> include/linux/mfd/syscon/exynos5-pmu.h | 4 +-
> 4 files changed, 197 insertions(+), 1 deletion(-)
> create mode 100644 drivers/mfd/exynos-lpass.c
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 2d1fb64..a7ec890 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -281,6 +281,14 @@ config MFD_DLN2
> etc. must be enabled in order to use the functionality of
> the device.
>
> +config MFD_EXYNOS_LPASS
> + tristate "Samsung Exynos SoC Low Power Audio Subsystem"
> + select MFD_CORE
> + select REGMAP_MMIO
> + help
> + Select this option to enable support for Samsung Exynos Low Power
> + Audio Subsystem.
> +
> config MFD_MC13XXX
> tristate
> depends on (SPI_MASTER || I2C)
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 2ba3ba3..41510bb 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
> obj-$(CONFIG_MFD_CROS_EC) += cros_ec.o
> obj-$(CONFIG_MFD_CROS_EC_I2C) += cros_ec_i2c.o
> obj-$(CONFIG_MFD_CROS_EC_SPI) += cros_ec_spi.o
> +obj-$(CONFIG_MFD_EXYNOS_LPASS) += exynos-lpass.o
>
> rtsx_pci-objs := rtsx_pcr.o rts5209.o rts5229.o rtl8411.o rts5227.o rts5249.o
> obj-$(CONFIG_MFD_RTSX_PCI) += rtsx_pci.o
> diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
> new file mode 100644
> index 0000000..956ce1f
> --- /dev/null
> +++ b/drivers/mfd/exynos-lpass.c
> @@ -0,0 +1,185 @@
> +/*
> + * Copyright (C) 2015 - 2016 Samsung Electronics Co., Ltd.
> + *
> + * Authors: Inha Song <ideal.song at samsung.com>
> + * Sylwester Nawrocki <s.nawrocki at samsung.com>
> + *
> + * Samsung Exynos SoC series Low Power Audio Subsystem driver.
> + *
> + * This module provides regmap for the Top SFR region and instantiates
> + * devices for IP blocks like DMAC, I2S, UART.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/mfd/syscon/exynos5-pmu.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/types.h>
> +
> +/* LPASS Top register definitions */
> +#define SFR_LPASS_CORE_SW_RESET (0x08)
> +#define LPASS_SB_SW_RESET (1 << 11)
> +#define LPASS_UART_SW_RESET (1 << 10)
> +#define LPASS_PCM_SW_RESET (1 << 9)
> +#define LPASS_I2S_SW_RESET (1 << 8)
> +#define LPASS_WDT1_SW_RESET (1 << 4)
> +#define LPASS_WDT0_SW_RESET (1 << 3)
> +#define LPASS_TIMER_SW_RESET (1 << 2)
> +#define LPASS_MEM_SW_RESET (1 << 1)
> +#define LPASS_DMA_SW_RESET (1 << 0)
> +
> +#define SFR_LPASS_INTR_CA5_MASK (0x48)
> +#define SFR_LPASS_INTR_CPU_MASK (0x58)
> +#define LPASS_INTR_APM (1 << 9)
> +#define LPASS_INTR_MIF (1 << 8)
> +#define LPASS_INTR_TIMER (1 << 7)
> +#define LPASS_INTR_DMA (1 << 6)
> +#define LPASS_INTR_GPIO (1 << 5)
> +#define LPASS_INTR_I2S (1 << 4)
> +#define LPASS_INTR_PCM (1 << 3)
> +#define LPASS_INTR_SLIMBUS (1 << 2)
> +#define LPASS_INTR_UART (1 << 1)
> +#define LPASS_INTR_SFR (1 << 0)
> +
> +struct exynos_lpass {
> + struct regmap *pmu;
> + struct regmap *top;
> +};
> +
> +static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
> +{
> + unsigned int val = 0;
> +
> + regmap_read(lpass->top, SFR_LPASS_CORE_SW_RESET, &val);
> +
> + val &= ~mask;
> + regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
> +
> + usleep_range(100, 150);
> +
> + val |= mask;
> + regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
> +}
> +
> +static void exynos_lpass_enable(struct exynos_lpass *lpass)
> +{
> + /* Unmask SFR, DMA and I2S interrupt */
> + regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK,
> + LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S);
> +
> + regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK,
> + LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S);
> +
> + /* Activate related PADs from retention state */
> + regmap_write(lpass->pmu, EXYNOS5433_PAD_RETENTION_AUD_OPTION,
> + EXYNOS5433_PAD_INITIATE_WAKEUP_FROM_LOWPWR);
> +
> + exynos_lpass_core_sw_reset(lpass, LPASS_I2S_SW_RESET);
> + exynos_lpass_core_sw_reset(lpass, LPASS_DMA_SW_RESET);
> + exynos_lpass_core_sw_reset(lpass, LPASS_MEM_SW_RESET);
> +}
> +
> +static void exynos_lpass_disable(struct exynos_lpass *lpass)
> +{
> + /* Mask any unmasked IP interrupt sources */
> + regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK, 0);
> + regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK, 0);
> +
> + /* Deactivate related PADs from retention state */
> + regmap_write(lpass->pmu, EXYNOS5433_PAD_RETENTION_AUD_OPTION, 0);
> +}
> +
> +static const struct regmap_config exynos_lpass_reg_conf = {
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> + .max_register = 0xfc,
> + .fast_io = true,
> +};
> +
> +static int exynos_lpass_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct exynos_lpass *lpass;
> + void __iomem *base_top;
> + struct resource *res;
> +
> + if (!dev->of_node)
> + return -ENODEV;
> +
> + lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
> + if (!lpass)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> + base_top = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base_top))
> + return PTR_ERR(base_top);
> +
> + lpass->top = regmap_init_mmio(dev, base_top,
> + &exynos_lpass_reg_conf);
> + if (IS_ERR(lpass->top)) {
> + dev_err(dev, "LPASS top regmap initialization failed\n");
> + return PTR_ERR(lpass->top);
> + }
> +
> + lpass->pmu = syscon_regmap_lookup_by_phandle(dev->of_node,
> + "samsung,pmu-syscon");
> + if (IS_ERR(lpass->pmu)) {
> + dev_err(dev, "Failed to lookup PMU regmap\n");
> + return PTR_ERR(lpass->pmu);
> + }
> +
> + platform_set_drvdata(pdev, lpass);
> + exynos_lpass_enable(lpass);
> +
> + return of_platform_populate(dev->of_node, NULL, NULL, dev);
> +}
> +
> +static int exynos_lpass_suspend(struct device *dev)
> +{
> + struct exynos_lpass *lpass = dev_get_drvdata(dev);
> +
> + exynos_lpass_disable(lpass);
> + return 0;
> +}
> +
> +static int exynos_lpass_resume(struct device *dev)
> +{
> + struct exynos_lpass *lpass = dev_get_drvdata(dev);
> +
> + exynos_lpass_enable(lpass);
> + return 0;
> +}
> +
> +static const struct of_device_id exynos_lpass_of_match[] = {
> + { .compatible = "samsung,exynos5433-lpass" },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, exynos_lpass_of_match);
> +
> +static SIMPLE_DEV_PM_OPS(lpass_pm_ops, exynos_lpass_suspend,
> + exynos_lpass_resume);
> +
> +static struct platform_driver exynos_lpass_driver = {
> + .driver = {
> + .name = "exynos-lpass",
> + .pm = &lpass_pm_ops,
> + .of_match_table = exynos_lpass_of_match,
> + },
> + .probe = exynos_lpass_probe,
> +};
> +module_platform_driver(exynos_lpass_driver);
> +
> +MODULE_DESCRIPTION("Samsung Low Power Audio Subsystem driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/mfd/syscon/exynos5-pmu.h b/include/linux/mfd/syscon/exynos5-pmu.h
> index 76f30f9..c28ff21 100644
> --- a/include/linux/mfd/syscon/exynos5-pmu.h
> +++ b/include/linux/mfd/syscon/exynos5-pmu.h
> @@ -43,8 +43,10 @@
> #define EXYNOS5433_MIPI_PHY2_CONTROL (0x718)
>
> #define EXYNOS5_PHY_ENABLE BIT(0)
> -
> #define EXYNOS5_MIPI_PHY_S_RESETN BIT(1)
> #define EXYNOS5_MIPI_PHY_M_RESETN BIT(2)
>
> +#define EXYNOS5433_PAD_RETENTION_AUD_OPTION (0x3028)
> +#define EXYNOS5433_PAD_INITIATE_WAKEUP_FROM_LOWPWR BIT(28)
> +
> #endif /* _LINUX_MFD_SYSCON_PMU_EXYNOS5_H_ */
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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