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/mfd/syscon.h>
19 #include <linux/of.h>
20 #include <linux/of_platform.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/regmap.h>
24 #include <linux/soc/samsung/exynos-regs-pmu.h>
25 #include <linux/types.h>
26
27 /* LPASS Top register definitions */
28 #define SFR_LPASS_CORE_SW_RESET 0x08
29 #define LPASS_SB_SW_RESET BIT(11)
30 #define LPASS_UART_SW_RESET BIT(10)
31 #define LPASS_PCM_SW_RESET BIT(9)
32 #define LPASS_I2S_SW_RESET BIT(8)
33 #define LPASS_WDT1_SW_RESET BIT(4)
34 #define LPASS_WDT0_SW_RESET BIT(3)
35 #define LPASS_TIMER_SW_RESET BIT(2)
36 #define LPASS_MEM_SW_RESET BIT(1)
37 #define LPASS_DMA_SW_RESET BIT(0)
38
39 #define SFR_LPASS_INTR_CA5_MASK 0x48
40 #define SFR_LPASS_INTR_CPU_MASK 0x58
41 #define LPASS_INTR_APM BIT(9)
42 #define LPASS_INTR_MIF BIT(8)
43 #define LPASS_INTR_TIMER BIT(7)
44 #define LPASS_INTR_DMA BIT(6)
45 #define LPASS_INTR_GPIO BIT(5)
46 #define LPASS_INTR_I2S BIT(4)
47 #define LPASS_INTR_PCM BIT(3)
48 #define LPASS_INTR_SLIMBUS BIT(2)
49 #define LPASS_INTR_UART BIT(1)
50 #define LPASS_INTR_SFR BIT(0)
51
52 struct exynos_lpass {
53 /* pointer to the LPASS TOP regmap */
54 struct regmap *top;
55 struct clk *sfr0_clk;
56 };
57
exynos_lpass_core_sw_reset(struct exynos_lpass * lpass,int mask)58 static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
59 {
60 unsigned int val = 0;
61
62 regmap_read(lpass->top, SFR_LPASS_CORE_SW_RESET, &val);
63
64 val &= ~mask;
65 regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
66
67 usleep_range(100, 150);
68
69 val |= mask;
70 regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
71 }
72
exynos_lpass_enable(struct exynos_lpass * lpass)73 static void exynos_lpass_enable(struct exynos_lpass *lpass)
74 {
75 clk_prepare_enable(lpass->sfr0_clk);
76
77 /* Unmask SFR, DMA and I2S interrupt */
78 regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK,
79 LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S);
80
81 regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK,
82 LPASS_INTR_SFR | LPASS_INTR_DMA | LPASS_INTR_I2S |
83 LPASS_INTR_UART);
84
85 exynos_lpass_core_sw_reset(lpass, LPASS_I2S_SW_RESET);
86 exynos_lpass_core_sw_reset(lpass, LPASS_DMA_SW_RESET);
87 exynos_lpass_core_sw_reset(lpass, LPASS_MEM_SW_RESET);
88 exynos_lpass_core_sw_reset(lpass, LPASS_UART_SW_RESET);
89 }
90
exynos_lpass_disable(struct exynos_lpass * lpass)91 static void exynos_lpass_disable(struct exynos_lpass *lpass)
92 {
93 /* Mask any unmasked IP interrupt sources */
94 regmap_write(lpass->top, SFR_LPASS_INTR_CPU_MASK, 0);
95 regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK, 0);
96
97 clk_disable_unprepare(lpass->sfr0_clk);
98 }
99
100 static const struct regmap_config exynos_lpass_reg_conf = {
101 .reg_bits = 32,
102 .reg_stride = 4,
103 .val_bits = 32,
104 .max_register = 0xfc,
105 .fast_io = true,
106 };
107
exynos_lpass_probe(struct platform_device * pdev)108 static int exynos_lpass_probe(struct platform_device *pdev)
109 {
110 struct device *dev = &pdev->dev;
111 struct exynos_lpass *lpass;
112 void __iomem *base_top;
113 struct resource *res;
114
115 lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
116 if (!lpass)
117 return -ENOMEM;
118
119 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
120 base_top = devm_ioremap_resource(dev, res);
121 if (IS_ERR(base_top))
122 return PTR_ERR(base_top);
123
124 lpass->sfr0_clk = devm_clk_get(dev, "sfr0_ctrl");
125 if (IS_ERR(lpass->sfr0_clk))
126 return PTR_ERR(lpass->sfr0_clk);
127
128 lpass->top = regmap_init_mmio(dev, base_top,
129 &exynos_lpass_reg_conf);
130 if (IS_ERR(lpass->top)) {
131 dev_err(dev, "LPASS top regmap initialization failed\n");
132 return PTR_ERR(lpass->top);
133 }
134
135 platform_set_drvdata(pdev, lpass);
136 pm_runtime_set_active(dev);
137 pm_runtime_enable(dev);
138 exynos_lpass_enable(lpass);
139
140 return devm_of_platform_populate(dev);
141 }
142
exynos_lpass_remove(struct platform_device * pdev)143 static int exynos_lpass_remove(struct platform_device *pdev)
144 {
145 struct exynos_lpass *lpass = platform_get_drvdata(pdev);
146
147 exynos_lpass_disable(lpass);
148 pm_runtime_disable(&pdev->dev);
149 if (!pm_runtime_status_suspended(&pdev->dev))
150 exynos_lpass_disable(lpass);
151 regmap_exit(lpass->top);
152
153 return 0;
154 }
155
exynos_lpass_suspend(struct device * dev)156 static int __maybe_unused exynos_lpass_suspend(struct device *dev)
157 {
158 struct exynos_lpass *lpass = dev_get_drvdata(dev);
159
160 exynos_lpass_disable(lpass);
161
162 return 0;
163 }
164
exynos_lpass_resume(struct device * dev)165 static int __maybe_unused exynos_lpass_resume(struct device *dev)
166 {
167 struct exynos_lpass *lpass = dev_get_drvdata(dev);
168
169 exynos_lpass_enable(lpass);
170
171 return 0;
172 }
173
174 static const struct dev_pm_ops lpass_pm_ops = {
175 SET_RUNTIME_PM_OPS(exynos_lpass_suspend, exynos_lpass_resume, NULL)
176 SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
177 pm_runtime_force_resume)
178 };
179
180 static const struct of_device_id exynos_lpass_of_match[] = {
181 { .compatible = "samsung,exynos5433-lpass" },
182 { },
183 };
184 MODULE_DEVICE_TABLE(of, exynos_lpass_of_match);
185
186 static struct platform_driver exynos_lpass_driver = {
187 .driver = {
188 .name = "exynos-lpass",
189 .pm = &lpass_pm_ops,
190 .of_match_table = exynos_lpass_of_match,
191 },
192 .probe = exynos_lpass_probe,
193 .remove = exynos_lpass_remove,
194 };
195 module_platform_driver(exynos_lpass_driver);
196
197 MODULE_DESCRIPTION("Samsung Low Power Audio Subsystem driver");
198 MODULE_LICENSE("GPL v2");
199