diff options
Diffstat (limited to 'drivers/mfd/exynos-lpass.c')
| -rw-r--r-- | drivers/mfd/exynos-lpass.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c new file mode 100644 index 000000000000..2e064fb8826f --- /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@samsung.com> + * Sylwester Nawrocki <s.nawrocki@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 BIT(11) +#define LPASS_UART_SW_RESET BIT(10) +#define LPASS_PCM_SW_RESET BIT(9) +#define LPASS_I2S_SW_RESET BIT(8) +#define LPASS_WDT1_SW_RESET BIT(4) +#define LPASS_WDT0_SW_RESET BIT(3) +#define LPASS_TIMER_SW_RESET BIT(2) +#define LPASS_MEM_SW_RESET BIT(1) +#define LPASS_DMA_SW_RESET BIT(0) + +#define SFR_LPASS_INTR_CA5_MASK 0x48 +#define SFR_LPASS_INTR_CPU_MASK 0x58 +#define LPASS_INTR_APM BIT(9) +#define LPASS_INTR_MIF BIT(8) +#define LPASS_INTR_TIMER BIT(7) +#define LPASS_INTR_DMA BIT(6) +#define LPASS_INTR_GPIO BIT(5) +#define LPASS_INTR_I2S BIT(4) +#define LPASS_INTR_PCM BIT(3) +#define LPASS_INTR_SLIMBUS BIT(2) +#define LPASS_INTR_UART BIT(1) +#define LPASS_INTR_SFR BIT(0) + +struct exynos_lpass { + /* pointer to the Power Management Unit regmap */ + struct regmap *pmu; + /* pointer to the LPASS TOP regmap */ + 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; + + 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 __maybe_unused exynos_lpass_suspend(struct device *dev) +{ + struct exynos_lpass *lpass = dev_get_drvdata(dev); + + exynos_lpass_disable(lpass); + + return 0; +} + +static int __maybe_unused exynos_lpass_resume(struct device *dev) +{ + struct exynos_lpass *lpass = dev_get_drvdata(dev); + + exynos_lpass_enable(lpass); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(lpass_pm_ops, exynos_lpass_suspend, + exynos_lpass_resume); + +static const struct of_device_id exynos_lpass_of_match[] = { + { .compatible = "samsung,exynos5433-lpass" }, + { }, +}; +MODULE_DEVICE_TABLE(of, exynos_lpass_of_match); + +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"); |