drivers/mfd/exynos-lpass.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2015 - 2016 Samsung Electronics Co., Ltd.
   4  *
   5  * Authors: Inha Song <ideal.song@samsung.com>
   6  *          Sylwester Nawrocki <s.nawrocki@samsung.com>
   7  *
   8  * Samsung Exynos SoC series Low Power Audio Subsystem driver.
   9  *
  10  * This module provides regmap for the Top SFR region and instantiates
  11  * devices for IP blocks like DMAC, I2S, UART.
  12  */
  13
  14 #include <linux/clk.h>
  15 #include <linux/delay.h>
  16 #include <linux/io.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/of_platform.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/pm_runtime.h>
  22 #include <linux/regmap.h>
  23 #include <linux/soc/samsung/exynos-regs-pmu.h>
  24 #include <linux/types.h>
  25
  26 /* LPASS Top register definitions */
  27 #define SFR_LPASS_CORE_SW_RESET         0x08
  28 #define  LPASS_SB_SW_RESET              BIT(11)
  29 #define  LPASS_UART_SW_RESET            BIT(10)
  30 #define  LPASS_PCM_SW_RESET             BIT(9)
  31 #define  LPASS_I2S_SW_RESET             BIT(8)
  32 #define  LPASS_WDT1_SW_RESET            BIT(4)
  33 #define  LPASS_WDT0_SW_RESET            BIT(3)
  34 #define  LPASS_TIMER_SW_RESET           BIT(2)
  35 #define  LPASS_MEM_SW_RESET             BIT(1)
  36 #define  LPASS_DMA_SW_RESET             BIT(0)
  37
  38 #define SFR_LPASS_INTR_CA5_MASK         0x48
  39 #define SFR_LPASS_INTR_CPU_MASK         0x58
  40 #define  LPASS_INTR_APM                 BIT(9)
  41 #define  LPASS_INTR_MIF                 BIT(8)
  42 #define  LPASS_INTR_TIMER               BIT(7)
  43 #define  LPASS_INTR_DMA                 BIT(6)
  44 #define  LPASS_INTR_GPIO                BIT(5)
  45 #define  LPASS_INTR_I2S                 BIT(4)
  46 #define  LPASS_INTR_PCM                 BIT(3)
  47 #define  LPASS_INTR_SLIMBUS             BIT(2)
  48 #define  LPASS_INTR_UART                BIT(1)
  49 #define  LPASS_INTR_SFR                 BIT(0)
  50
  51 struct exynos_lpass {
  52         /* pointer to the LPASS TOP regmap */
  53         struct regmap *top;
  54         struct clk *sfr0_clk;
  55 };
  56
  57 static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
  58 {
  59         unsigned int val = 0;
  60
  61         regmap_read(lpass->top, SFR_LPASS_CORE_SW_RESET, &val);
  62
  63         val &= ~mask;
  64         regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
  65
  66         usleep_range(100, 150);
  67
  68         val |= mask;
  69         regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
  70 }
  71
  72 static void exynos_lpass_enable(struct exynos_lpass *lpass)
  73 {
  74         clk_prepare_enable(lpass->sfr0_clk);
  75
  76         /* Unmask SFR, DMA and I2S interrupt */
  77         regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK,
  78                      LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S);
  79
  80         regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK,
  81                      LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S |
  82                      LPASS_INTR_UART);
  83
  84         exynos_lpass_core_sw_reset(lpass, LPASS_I2S_SW_RESET);
  85         exynos_lpass_core_sw_reset(lpass, LPASS_DMA_SW_RESET);
  86         exynos_lpass_core_sw_reset(lpass, LPASS_MEM_SW_RESET);
  87         exynos_lpass_core_sw_reset(lpass, LPASS_UART_SW_RESET);
  88 }
  89
  90 static void exynos_lpass_disable(struct exynos_lpass *lpass)
  91 {
  92         /* Mask any unmasked IP interrupt sources */
  93         regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK, 0);
  94         regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK, 0);
  95
  96         clk_disable_unprepare(lpass->sfr0_clk);
  97 }
  98
  99 static const struct regmap_config exynos_lpass_reg_conf = {
 100         .reg_bits       = 32,
 101         .reg_stride     = 4,
 102         .val_bits       = 32,
 103         .max_register   = 0xfc,
 104         .fast_io        = true,
 105 };
 106
 107 static int exynos_lpass_probe(struct platform_device *pdev)
 108 {
 109         struct device *dev = &pdev->dev;
 110         struct exynos_lpass *lpass;
 111         void __iomem *base_top;
 112
 113         lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
 114         if (!lpass)
 115                 return -ENOMEM;
 116
 117         base_top = devm_platform_ioremap_resource(pdev, 0);
 118         if (IS_ERR(base_top))
 119                 return PTR_ERR(base_top);
 120
 121         lpass->sfr0_clk = devm_clk_get(dev, "sfr0_ctrl");
 122         if (IS_ERR(lpass->sfr0_clk))
 123                 return PTR_ERR(lpass->sfr0_clk);
 124
 125         lpass->top = regmap_init_mmio(dev, base_top,
 126                                         &exynos_lpass_reg_conf);
 127         if (IS_ERR(lpass->top)) {
 128                 dev_err(dev, "LPASS top regmap initialization failed\n");
 129                 return PTR_ERR(lpass->top);
 130         }
 131
 132         platform_set_drvdata(pdev, lpass);
 133         pm_runtime_set_active(dev);
 134         pm_runtime_enable(dev);
 135         exynos_lpass_enable(lpass);
 136
 137         return devm_of_platform_populate(dev);
 138 }
 139
 140 static int exynos_lpass_remove(struct platform_device *pdev)
 141 {
 142         struct exynos_lpass *lpass = platform_get_drvdata(pdev);
 143
 144         exynos_lpass_disable(lpass);
 145         pm_runtime_disable(&pdev->dev);
 146         if (!pm_runtime_status_suspended(&pdev->dev))
 147                 exynos_lpass_disable(lpass);
 148         regmap_exit(lpass->top);
 149
 150         return 0;
 151 }
 152
 153 static int __maybe_unused exynos_lpass_suspend(struct device *dev)
 154 {
 155         struct exynos_lpass *lpass = dev_get_drvdata(dev);
 156
 157         exynos_lpass_disable(lpass);
 158
 159         return 0;
 160 }
 161
 162 static int __maybe_unused exynos_lpass_resume(struct device *dev)
 163 {
 164         struct exynos_lpass *lpass = dev_get_drvdata(dev);
 165
 166         exynos_lpass_enable(lpass);
 167
 168         return 0;
 169 }
 170
 171 static const struct dev_pm_ops lpass_pm_ops = {
 172         SET_RUNTIME_PM_OPS(exynos_lpass_suspend, exynos_lpass_resume, NULL)
 173         SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 174                                      pm_runtime_force_resume)
 175 };
 176
 177 static const struct of_device_id exynos_lpass_of_match[] = {
 178         { .compatible = "samsung,exynos5433-lpass" },
 179         { },
 180 };
 181 MODULE_DEVICE_TABLE(of, exynos_lpass_of_match);
 182
 183 static struct platform_driver exynos_lpass_driver = {
 184         .driver = {
 185                 .name           = "exynos-lpass",
 186                 .pm             = &lpass_pm_ops,
 187                 .of_match_table = exynos_lpass_of_match,
 188         },
 189         .probe  = exynos_lpass_probe,
 190         .remove = exynos_lpass_remove,
 191 };
 192 module_platform_driver(exynos_lpass_driver);
 193
 194 MODULE_DESCRIPTION("Samsung Low Power Audio Subsystem driver");
 195 MODULE_LICENSE("GPL v2");