xref: /linux/sound/soc/sunxi/sun8i-adda-pr-regmap.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * This driver provides regmap to access to analog part of audio codec
4  * found on Allwinner A23, A31s, A33, H3 and A64 Socs
5  *
6  * Copyright 2016 Chen-Yu Tsai <wens@csie.org>
7  * Copyright (C) 2018 Vasily Khoruzhick <anarsoul@gmail.com>
8  */
9 
10 #include <linux/io.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 
15 #include "sun8i-adda-pr-regmap.h"
16 
17 /* Analog control register access bits */
18 #define ADDA_PR			0x0		/* PRCM base + 0x1c0 */
19 #define ADDA_PR_RESET			BIT(28)
20 #define ADDA_PR_WRITE			BIT(24)
21 #define ADDA_PR_ADDR_SHIFT		16
22 #define ADDA_PR_ADDR_MASK		GENMASK(4, 0)
23 #define ADDA_PR_DATA_IN_SHIFT		8
24 #define ADDA_PR_DATA_IN_MASK		GENMASK(7, 0)
25 #define ADDA_PR_DATA_OUT_SHIFT		0
26 #define ADDA_PR_DATA_OUT_MASK		GENMASK(7, 0)
27 
28 /* regmap access bits */
29 static int adda_reg_read(void *context, unsigned int reg, unsigned int *val)
30 {
31 	void __iomem *base = (void __iomem *)context;
32 	u32 tmp;
33 
34 	/* De-assert reset */
35 	writel(readl(base) | ADDA_PR_RESET, base);
36 
37 	/* Clear write bit */
38 	writel(readl(base) & ~ADDA_PR_WRITE, base);
39 
40 	/* Set register address */
41 	tmp = readl(base);
42 	tmp &= ~(ADDA_PR_ADDR_MASK << ADDA_PR_ADDR_SHIFT);
43 	tmp |= (reg & ADDA_PR_ADDR_MASK) << ADDA_PR_ADDR_SHIFT;
44 	writel(tmp, base);
45 
46 	/* Read back value */
47 	*val = readl(base) & ADDA_PR_DATA_OUT_MASK;
48 
49 	return 0;
50 }
51 
52 static int adda_reg_write(void *context, unsigned int reg, unsigned int val)
53 {
54 	void __iomem *base = (void __iomem *)context;
55 	u32 tmp;
56 
57 	/* De-assert reset */
58 	writel(readl(base) | ADDA_PR_RESET, base);
59 
60 	/* Set register address */
61 	tmp = readl(base);
62 	tmp &= ~(ADDA_PR_ADDR_MASK << ADDA_PR_ADDR_SHIFT);
63 	tmp |= (reg & ADDA_PR_ADDR_MASK) << ADDA_PR_ADDR_SHIFT;
64 	writel(tmp, base);
65 
66 	/* Set data to write */
67 	tmp = readl(base);
68 	tmp &= ~(ADDA_PR_DATA_IN_MASK << ADDA_PR_DATA_IN_SHIFT);
69 	tmp |= (val & ADDA_PR_DATA_IN_MASK) << ADDA_PR_DATA_IN_SHIFT;
70 	writel(tmp, base);
71 
72 	/* Set write bit to signal a write */
73 	writel(readl(base) | ADDA_PR_WRITE, base);
74 
75 	/* Clear write bit */
76 	writel(readl(base) & ~ADDA_PR_WRITE, base);
77 
78 	return 0;
79 }
80 
81 static const struct regmap_config adda_pr_regmap_cfg = {
82 	.name		= "adda-pr",
83 	.reg_bits	= 5,
84 	.reg_stride	= 1,
85 	.val_bits	= 8,
86 	.reg_read	= adda_reg_read,
87 	.reg_write	= adda_reg_write,
88 	.fast_io	= true,
89 	.max_register	= 31,
90 };
91 
92 struct regmap *sun8i_adda_pr_regmap_init(struct device *dev,
93 					 void __iomem *base)
94 {
95 	return devm_regmap_init(dev, NULL, base, &adda_pr_regmap_cfg);
96 }
97 EXPORT_SYMBOL_GPL(sun8i_adda_pr_regmap_init);
98 
99 MODULE_DESCRIPTION("Allwinner analog audio codec regmap driver");
100 MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
101 MODULE_LICENSE("GPL");
102 MODULE_ALIAS("platform:sunxi-adda-pr");
103