xref: /linux/drivers/mfd/exynos-lpass.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
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 };
105 
106 static void exynos_lpass_disable_lpass(void *data)
107 {
108 	struct platform_device *pdev = data;
109 	struct exynos_lpass *lpass = platform_get_drvdata(pdev);
110 
111 	pm_runtime_disable(&pdev->dev);
112 	if (!pm_runtime_status_suspended(&pdev->dev))
113 		exynos_lpass_disable(lpass);
114 }
115 
116 static int exynos_lpass_probe(struct platform_device *pdev)
117 {
118 	struct device *dev = &pdev->dev;
119 	struct exynos_lpass *lpass;
120 	void __iomem *base_top;
121 	int ret;
122 
123 	lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
124 	if (!lpass)
125 		return -ENOMEM;
126 
127 	base_top = devm_platform_ioremap_resource(pdev, 0);
128 	if (IS_ERR(base_top))
129 		return PTR_ERR(base_top);
130 
131 	lpass->sfr0_clk = devm_clk_get(dev, "sfr0_ctrl");
132 	if (IS_ERR(lpass->sfr0_clk))
133 		return PTR_ERR(lpass->sfr0_clk);
134 
135 	lpass->top = devm_regmap_init_mmio(dev, base_top,
136 					   &exynos_lpass_reg_conf);
137 	if (IS_ERR(lpass->top)) {
138 		dev_err(dev, "LPASS top regmap initialization failed\n");
139 		return PTR_ERR(lpass->top);
140 	}
141 
142 	platform_set_drvdata(pdev, lpass);
143 	pm_runtime_set_active(dev);
144 	pm_runtime_enable(dev);
145 	exynos_lpass_enable(lpass);
146 
147 	ret = devm_add_action_or_reset(dev, exynos_lpass_disable_lpass, pdev);
148 	if (ret)
149 		return ret;
150 
151 	return devm_of_platform_populate(dev);
152 }
153 
154 static int __maybe_unused exynos_lpass_suspend(struct device *dev)
155 {
156 	struct exynos_lpass *lpass = dev_get_drvdata(dev);
157 
158 	exynos_lpass_disable(lpass);
159 
160 	return 0;
161 }
162 
163 static int __maybe_unused exynos_lpass_resume(struct device *dev)
164 {
165 	struct exynos_lpass *lpass = dev_get_drvdata(dev);
166 
167 	exynos_lpass_enable(lpass);
168 
169 	return 0;
170 }
171 
172 static const struct dev_pm_ops lpass_pm_ops = {
173 	SET_RUNTIME_PM_OPS(exynos_lpass_suspend, exynos_lpass_resume, NULL)
174 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
175 				     pm_runtime_force_resume)
176 };
177 
178 static const struct of_device_id exynos_lpass_of_match[] = {
179 	{ .compatible = "samsung,exynos5433-lpass" },
180 	{ },
181 };
182 MODULE_DEVICE_TABLE(of, exynos_lpass_of_match);
183 
184 static struct platform_driver exynos_lpass_driver = {
185 	.driver	= {
186 		.name		= "exynos-lpass",
187 		.pm		= &lpass_pm_ops,
188 		.of_match_table	= exynos_lpass_of_match,
189 	},
190 	.probe	= exynos_lpass_probe,
191 };
192 module_platform_driver(exynos_lpass_driver);
193 
194 MODULE_DESCRIPTION("Samsung Low Power Audio Subsystem driver");
195 MODULE_LICENSE("GPL v2");
196