1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * tegra20_das.c - Tegra20 DAS driver
4 *
5 * Author: Stephen Warren <swarren@nvidia.com>
6 * Copyright (C) 2010 - NVIDIA, Inc.
7 */
8
9#include <linux/device.h>
10#include <linux/io.h>
11#include <linux/module.h>
12#include <linux/platform_device.h>
13#include <linux/regmap.h>
14#include <linux/slab.h>
15#include <sound/soc.h>
16#include "tegra20_das.h"
17
18#define DRV_NAME "tegra20-das"
19
20static struct tegra20_das *das;
21
22static inline void tegra20_das_write(u32 reg, u32 val)
23{
24	regmap_write(das->regmap, reg, val);
25}
26
27static inline u32 tegra20_das_read(u32 reg)
28{
29	u32 val;
30
31	regmap_read(das->regmap, reg, &val);
32	return val;
33}
34
35int tegra20_das_connect_dap_to_dac(int dap, int dac)
36{
37	u32 addr;
38	u32 reg;
39
40	if (!das)
41		return -ENODEV;
42
43	addr = TEGRA20_DAS_DAP_CTRL_SEL +
44		(dap * TEGRA20_DAS_DAP_CTRL_SEL_STRIDE);
45	reg = dac << TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P;
46
47	tegra20_das_write(addr, reg);
48
49	return 0;
50}
51EXPORT_SYMBOL_GPL(tegra20_das_connect_dap_to_dac);
52
53int tegra20_das_connect_dap_to_dap(int dap, int otherdap, int master,
54				   int sdata1rx, int sdata2rx)
55{
56	u32 addr;
57	u32 reg;
58
59	if (!das)
60		return -ENODEV;
61
62	addr = TEGRA20_DAS_DAP_CTRL_SEL +
63		(dap * TEGRA20_DAS_DAP_CTRL_SEL_STRIDE);
64	reg = otherdap << TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P |
65		!!sdata2rx << TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA2_TX_RX_P |
66		!!sdata1rx << TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA1_TX_RX_P |
67		!!master << TEGRA20_DAS_DAP_CTRL_SEL_DAP_MS_SEL_P;
68
69	tegra20_das_write(addr, reg);
70
71	return 0;
72}
73EXPORT_SYMBOL_GPL(tegra20_das_connect_dap_to_dap);
74
75int tegra20_das_connect_dac_to_dap(int dac, int dap)
76{
77	u32 addr;
78	u32 reg;
79
80	if (!das)
81		return -ENODEV;
82
83	addr = TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL +
84		(dac * TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE);
85	reg = dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_P |
86		dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_P |
87		dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_P;
88
89	tegra20_das_write(addr, reg);
90
91	return 0;
92}
93EXPORT_SYMBOL_GPL(tegra20_das_connect_dac_to_dap);
94
95#define LAST_REG(name) \
96	(TEGRA20_DAS_##name + \
97	 (TEGRA20_DAS_##name##_STRIDE * (TEGRA20_DAS_##name##_COUNT - 1)))
98
99static bool tegra20_das_wr_rd_reg(struct device *dev, unsigned int reg)
100{
101	if (reg <= LAST_REG(DAP_CTRL_SEL))
102		return true;
103	if ((reg >= TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL) &&
104	    (reg <= LAST_REG(DAC_INPUT_DATA_CLK_SEL)))
105		return true;
106
107	return false;
108}
109
110static const struct regmap_config tegra20_das_regmap_config = {
111	.reg_bits = 32,
112	.reg_stride = 4,
113	.val_bits = 32,
114	.max_register = LAST_REG(DAC_INPUT_DATA_CLK_SEL),
115	.writeable_reg = tegra20_das_wr_rd_reg,
116	.readable_reg = tegra20_das_wr_rd_reg,
117	.cache_type = REGCACHE_FLAT,
118};
119
120static int tegra20_das_probe(struct platform_device *pdev)
121{
122	void __iomem *regs;
123	int ret = 0;
124
125	if (das)
126		return -ENODEV;
127
128	das = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_das), GFP_KERNEL);
129	if (!das) {
130		ret = -ENOMEM;
131		goto err;
132	}
133	das->dev = &pdev->dev;
134
135	regs = devm_platform_ioremap_resource(pdev, 0);
136	if (IS_ERR(regs)) {
137		ret = PTR_ERR(regs);
138		goto err;
139	}
140
141	das->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
142					    &tegra20_das_regmap_config);
143	if (IS_ERR(das->regmap)) {
144		dev_err(&pdev->dev, "regmap init failed\n");
145		ret = PTR_ERR(das->regmap);
146		goto err;
147	}
148
149	ret = tegra20_das_connect_dap_to_dac(TEGRA20_DAS_DAP_ID_1,
150					     TEGRA20_DAS_DAP_SEL_DAC1);
151	if (ret) {
152		dev_err(&pdev->dev, "Can't set up DAS DAP connection\n");
153		goto err;
154	}
155	ret = tegra20_das_connect_dac_to_dap(TEGRA20_DAS_DAC_ID_1,
156					     TEGRA20_DAS_DAC_SEL_DAP1);
157	if (ret) {
158		dev_err(&pdev->dev, "Can't set up DAS DAC connection\n");
159		goto err;
160	}
161
162	ret = tegra20_das_connect_dap_to_dac(TEGRA20_DAS_DAP_ID_3,
163					     TEGRA20_DAS_DAP_SEL_DAC3);
164	if (ret) {
165		dev_err(&pdev->dev, "Can't set up DAS DAP connection\n");
166		goto err;
167	}
168	ret = tegra20_das_connect_dac_to_dap(TEGRA20_DAS_DAC_ID_3,
169					     TEGRA20_DAS_DAC_SEL_DAP3);
170	if (ret) {
171		dev_err(&pdev->dev, "Can't set up DAS DAC connection\n");
172		goto err;
173	}
174
175	platform_set_drvdata(pdev, das);
176
177	return 0;
178
179err:
180	das = NULL;
181	return ret;
182}
183
184static int tegra20_das_remove(struct platform_device *pdev)
185{
186	if (!das)
187		return -ENODEV;
188
189	das = NULL;
190
191	return 0;
192}
193
194static const struct of_device_id tegra20_das_of_match[] = {
195	{ .compatible = "nvidia,tegra20-das", },
196	{},
197};
198
199static struct platform_driver tegra20_das_driver = {
200	.probe = tegra20_das_probe,
201	.remove = tegra20_das_remove,
202	.driver = {
203		.name = DRV_NAME,
204		.of_match_table = tegra20_das_of_match,
205	},
206};
207module_platform_driver(tegra20_das_driver);
208
209MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
210MODULE_DESCRIPTION("Tegra20 DAS driver");
211MODULE_LICENSE("GPL");
212MODULE_ALIAS("platform:" DRV_NAME);
213MODULE_DEVICE_TABLE(of, tegra20_das_of_match);
214