1 /*
2  * tegra_das.c - Tegra DAS driver
3  *
4  * Author: Stephen Warren <swarren@nvidia.com>
5  * Copyright (C) 2010 - NVIDIA, Inc.
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * version 2 as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19  * 02110-1301 USA
20  *
21  */
22 
23 #include <linux/module.h>
24 #include <linux/debugfs.h>
25 #include <linux/device.h>
26 #include <linux/platform_device.h>
27 #include <linux/seq_file.h>
28 #include <linux/slab.h>
29 #include <linux/io.h>
30 #include <mach/iomap.h>
31 #include <sound/soc.h>
32 #include "tegra_das.h"
33 
34 #define DRV_NAME "tegra-das"
35 
36 static struct tegra_das *das;
37 
tegra_das_write(u32 reg,u32 val)38 static inline void tegra_das_write(u32 reg, u32 val)
39 {
40 	__raw_writel(val, das->regs + reg);
41 }
42 
tegra_das_read(u32 reg)43 static inline u32 tegra_das_read(u32 reg)
44 {
45 	return __raw_readl(das->regs + reg);
46 }
47 
tegra_das_connect_dap_to_dac(int dap,int dac)48 int tegra_das_connect_dap_to_dac(int dap, int dac)
49 {
50 	u32 addr;
51 	u32 reg;
52 
53 	if (!das)
54 		return -ENODEV;
55 
56 	addr = TEGRA_DAS_DAP_CTRL_SEL +
57 		(dap * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
58 	reg = dac << TEGRA_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P;
59 
60 	tegra_das_write(addr, reg);
61 
62 	return 0;
63 }
64 EXPORT_SYMBOL_GPL(tegra_das_connect_dap_to_dac);
65 
tegra_das_connect_dap_to_dap(int dap,int otherdap,int master,int sdata1rx,int sdata2rx)66 int tegra_das_connect_dap_to_dap(int dap, int otherdap, int master,
67 					int sdata1rx, int sdata2rx)
68 {
69 	u32 addr;
70 	u32 reg;
71 
72 	if (!das)
73 		return -ENODEV;
74 
75 	addr = TEGRA_DAS_DAP_CTRL_SEL +
76 		(dap * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
77 	reg = otherdap << TEGRA_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P |
78 		!!sdata2rx << TEGRA_DAS_DAP_CTRL_SEL_DAP_SDATA2_TX_RX_P |
79 		!!sdata1rx << TEGRA_DAS_DAP_CTRL_SEL_DAP_SDATA1_TX_RX_P |
80 		!!master << TEGRA_DAS_DAP_CTRL_SEL_DAP_MS_SEL_P;
81 
82 	tegra_das_write(addr, reg);
83 
84 	return 0;
85 }
86 EXPORT_SYMBOL_GPL(tegra_das_connect_dap_to_dap);
87 
tegra_das_connect_dac_to_dap(int dac,int dap)88 int tegra_das_connect_dac_to_dap(int dac, int dap)
89 {
90 	u32 addr;
91 	u32 reg;
92 
93 	if (!das)
94 		return -ENODEV;
95 
96 	addr = TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL +
97 		(dac * TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE);
98 	reg = dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_P |
99 		dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_P |
100 		dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_P;
101 
102 	tegra_das_write(addr, reg);
103 
104 	return 0;
105 }
106 EXPORT_SYMBOL_GPL(tegra_das_connect_dac_to_dap);
107 
108 #ifdef CONFIG_DEBUG_FS
tegra_das_show(struct seq_file * s,void * unused)109 static int tegra_das_show(struct seq_file *s, void *unused)
110 {
111 	int i;
112 	u32 addr;
113 	u32 reg;
114 
115 	for (i = 0; i < TEGRA_DAS_DAP_CTRL_SEL_COUNT; i++) {
116 		addr = TEGRA_DAS_DAP_CTRL_SEL +
117 			(i * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
118 		reg = tegra_das_read(addr);
119 		seq_printf(s, "TEGRA_DAS_DAP_CTRL_SEL[%d] = %08x\n", i, reg);
120 	}
121 
122 	for (i = 0; i < TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_COUNT; i++) {
123 		addr = TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL +
124 			(i * TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE);
125 		reg = tegra_das_read(addr);
126 		seq_printf(s, "TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL[%d] = %08x\n",
127 				 i, reg);
128 	}
129 
130 	return 0;
131 }
132 
tegra_das_debug_open(struct inode * inode,struct file * file)133 static int tegra_das_debug_open(struct inode *inode, struct file *file)
134 {
135 	return single_open(file, tegra_das_show, inode->i_private);
136 }
137 
138 static const struct file_operations tegra_das_debug_fops = {
139 	.open    = tegra_das_debug_open,
140 	.read    = seq_read,
141 	.llseek  = seq_lseek,
142 	.release = single_release,
143 };
144 
tegra_das_debug_add(struct tegra_das * das)145 static void tegra_das_debug_add(struct tegra_das *das)
146 {
147 	das->debug = debugfs_create_file(DRV_NAME, S_IRUGO,
148 					 snd_soc_debugfs_root, das,
149 					 &tegra_das_debug_fops);
150 }
151 
tegra_das_debug_remove(struct tegra_das * das)152 static void tegra_das_debug_remove(struct tegra_das *das)
153 {
154 	if (das->debug)
155 		debugfs_remove(das->debug);
156 }
157 #else
tegra_das_debug_add(struct tegra_das * das)158 static inline void tegra_das_debug_add(struct tegra_das *das)
159 {
160 }
161 
tegra_das_debug_remove(struct tegra_das * das)162 static inline void tegra_das_debug_remove(struct tegra_das *das)
163 {
164 }
165 #endif
166 
tegra_das_probe(struct platform_device * pdev)167 static int __devinit tegra_das_probe(struct platform_device *pdev)
168 {
169 	struct resource *res, *region;
170 	int ret = 0;
171 
172 	if (das)
173 		return -ENODEV;
174 
175 	das = devm_kzalloc(&pdev->dev, sizeof(struct tegra_das), GFP_KERNEL);
176 	if (!das) {
177 		dev_err(&pdev->dev, "Can't allocate tegra_das\n");
178 		ret = -ENOMEM;
179 		goto err;
180 	}
181 	das->dev = &pdev->dev;
182 
183 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
184 	if (!res) {
185 		dev_err(&pdev->dev, "No memory resource\n");
186 		ret = -ENODEV;
187 		goto err;
188 	}
189 
190 	region = devm_request_mem_region(&pdev->dev, res->start,
191 					 resource_size(res), pdev->name);
192 	if (!region) {
193 		dev_err(&pdev->dev, "Memory region already claimed\n");
194 		ret = -EBUSY;
195 		goto err;
196 	}
197 
198 	das->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
199 	if (!das->regs) {
200 		dev_err(&pdev->dev, "ioremap failed\n");
201 		ret = -ENOMEM;
202 		goto err;
203 	}
204 
205 	ret = tegra_das_connect_dap_to_dac(TEGRA_DAS_DAP_ID_1,
206 					   TEGRA_DAS_DAP_SEL_DAC1);
207 	if (ret) {
208 		dev_err(&pdev->dev, "Can't set up DAS DAP connection\n");
209 		goto err;
210 	}
211 	ret = tegra_das_connect_dac_to_dap(TEGRA_DAS_DAC_ID_1,
212 					   TEGRA_DAS_DAC_SEL_DAP1);
213 	if (ret) {
214 		dev_err(&pdev->dev, "Can't set up DAS DAC connection\n");
215 		goto err;
216 	}
217 
218 	tegra_das_debug_add(das);
219 
220 	platform_set_drvdata(pdev, das);
221 
222 	return 0;
223 
224 err:
225 	das = NULL;
226 	return ret;
227 }
228 
tegra_das_remove(struct platform_device * pdev)229 static int __devexit tegra_das_remove(struct platform_device *pdev)
230 {
231 	if (!das)
232 		return -ENODEV;
233 
234 	tegra_das_debug_remove(das);
235 
236 	das = NULL;
237 
238 	return 0;
239 }
240 
241 static const struct of_device_id tegra_das_of_match[] __devinitconst = {
242 	{ .compatible = "nvidia,tegra20-das", },
243 	{},
244 };
245 
246 static struct platform_driver tegra_das_driver = {
247 	.probe = tegra_das_probe,
248 	.remove = __devexit_p(tegra_das_remove),
249 	.driver = {
250 		.name = DRV_NAME,
251 		.owner = THIS_MODULE,
252 		.of_match_table = tegra_das_of_match,
253 	},
254 };
255 module_platform_driver(tegra_das_driver);
256 
257 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
258 MODULE_DESCRIPTION("Tegra DAS driver");
259 MODULE_LICENSE("GPL");
260 MODULE_ALIAS("platform:" DRV_NAME);
261 MODULE_DEVICE_TABLE(of, tegra_das_of_match);
262