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
51struct exynos_lpass {
52 /* pointer to the LPASS TOP regmap */
53 struct regmap *top;
54 struct clk *sfr0_clk;
55};
56
57static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
58{
59 unsigned int val = 0;
60
61 regmap_read(map: lpass->top, SFR_LPASS_CORE_SW_RESET, val: &val);
62
63 val &= ~mask;
64 regmap_write(map: lpass->top, SFR_LPASS_CORE_SW_RESET, val);
65
66 usleep_range(min: 100, max: 150);
67
68 val |= mask;
69 regmap_write(map: lpass->top, SFR_LPASS_CORE_SW_RESET, val);
70}
71
72static void exynos_lpass_enable(struct exynos_lpass *lpass)
73{
74 clk_prepare_enable(clk: lpass->sfr0_clk);
75
76 /* Unmask SFR, DMA and I2S interrupt */
77 regmap_write(map: lpass->top, SFR_LPASS_INTR_CA5_MASK,
78 LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S);
79
80 regmap_write(map: 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
90static void exynos_lpass_disable(struct exynos_lpass *lpass)
91{
92 /* Mask any unmasked IP interrupt sources */
93 regmap_write(map: lpass->top, SFR_LPASS_INTR_CPU_MASK, val: 0);
94 regmap_write(map: lpass->top, SFR_LPASS_INTR_CA5_MASK, val: 0);
95
96 clk_disable_unprepare(clk: lpass->sfr0_clk);
97}
98
99static 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
107static 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, size: sizeof(*lpass), GFP_KERNEL);
114 if (!lpass)
115 return -ENOMEM;
116
117 base_top = devm_platform_ioremap_resource(pdev, index: 0);
118 if (IS_ERR(ptr: base_top))
119 return PTR_ERR(ptr: base_top);
120
121 lpass->sfr0_clk = devm_clk_get(dev, id: "sfr0_ctrl");
122 if (IS_ERR(ptr: lpass->sfr0_clk))
123 return PTR_ERR(ptr: lpass->sfr0_clk);
124
125 lpass->top = regmap_init_mmio(dev, base_top,
126 &exynos_lpass_reg_conf);
127 if (IS_ERR(ptr: lpass->top)) {
128 dev_err(dev, "LPASS top regmap initialization failed\n");
129 return PTR_ERR(ptr: lpass->top);
130 }
131
132 platform_set_drvdata(pdev, data: 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
140static 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(dev: &pdev->dev);
146 if (!pm_runtime_status_suspended(dev: &pdev->dev))
147 exynos_lpass_disable(lpass);
148 regmap_exit(map: lpass->top);
149
150 return 0;
151}
152
153static 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
162static 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
171static 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
177static const struct of_device_id exynos_lpass_of_match[] = {
178 { .compatible = "samsung,exynos5433-lpass" },
179 { },
180};
181MODULE_DEVICE_TABLE(of, exynos_lpass_of_match);
182
183static 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};
192module_platform_driver(exynos_lpass_driver);
193
194MODULE_DESCRIPTION("Samsung Low Power Audio Subsystem driver");
195MODULE_LICENSE("GPL v2");
196

source code of linux/drivers/mfd/exynos-lpass.c