xref: /openbmc/linux/sound/soc/fsl/imx-audmux.c (revision e23feb16)
1 /*
2  * Copyright 2012 Freescale Semiconductor, Inc.
3  * Copyright 2012 Linaro Ltd.
4  * Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
5  *
6  * Initial development of this code was funded by
7  * Phytec Messtechnik GmbH, http://www.phytec.de
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #include <linux/clk.h>
21 #include <linux/debugfs.h>
22 #include <linux/err.h>
23 #include <linux/io.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/platform_device.h>
28 #include <linux/slab.h>
29 
30 #include "imx-audmux.h"
31 
32 #define DRIVER_NAME "imx-audmux"
33 
34 static struct clk *audmux_clk;
35 static void __iomem *audmux_base;
36 
37 #define IMX_AUDMUX_V2_PTCR(x)		((x) * 8)
38 #define IMX_AUDMUX_V2_PDCR(x)		((x) * 8 + 4)
39 
40 #ifdef CONFIG_DEBUG_FS
41 static struct dentry *audmux_debugfs_root;
42 
43 /* There is an annoying discontinuity in the SSI numbering with regard
44  * to the Linux number of the devices */
45 static const char *audmux_port_string(int port)
46 {
47 	switch (port) {
48 	case MX31_AUDMUX_PORT1_SSI0:
49 		return "imx-ssi.0";
50 	case MX31_AUDMUX_PORT2_SSI1:
51 		return "imx-ssi.1";
52 	case MX31_AUDMUX_PORT3_SSI_PINS_3:
53 		return "SSI3";
54 	case MX31_AUDMUX_PORT4_SSI_PINS_4:
55 		return "SSI4";
56 	case MX31_AUDMUX_PORT5_SSI_PINS_5:
57 		return "SSI5";
58 	case MX31_AUDMUX_PORT6_SSI_PINS_6:
59 		return "SSI6";
60 	default:
61 		return "UNKNOWN";
62 	}
63 }
64 
65 static ssize_t audmux_read_file(struct file *file, char __user *user_buf,
66 				size_t count, loff_t *ppos)
67 {
68 	ssize_t ret;
69 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
70 	int port = (int)file->private_data;
71 	u32 pdcr, ptcr;
72 
73 	if (!buf)
74 		return -ENOMEM;
75 
76 	if (audmux_clk) {
77 		ret = clk_prepare_enable(audmux_clk);
78 		if (ret)
79 			return ret;
80 	}
81 
82 	ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
83 	pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
84 
85 	if (audmux_clk)
86 		clk_disable_unprepare(audmux_clk);
87 
88 	ret = snprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
89 		       pdcr, ptcr);
90 
91 	if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
92 		ret += snprintf(buf + ret, PAGE_SIZE - ret,
93 				"TxFS output from %s, ",
94 				audmux_port_string((ptcr >> 27) & 0x7));
95 	else
96 		ret += snprintf(buf + ret, PAGE_SIZE - ret,
97 				"TxFS input, ");
98 
99 	if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
100 		ret += snprintf(buf + ret, PAGE_SIZE - ret,
101 				"TxClk output from %s",
102 				audmux_port_string((ptcr >> 22) & 0x7));
103 	else
104 		ret += snprintf(buf + ret, PAGE_SIZE - ret,
105 				"TxClk input");
106 
107 	ret += snprintf(buf + ret, PAGE_SIZE - ret, "\n");
108 
109 	if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
110 		ret += snprintf(buf + ret, PAGE_SIZE - ret,
111 				"Port is symmetric");
112 	} else {
113 		if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
114 			ret += snprintf(buf + ret, PAGE_SIZE - ret,
115 					"RxFS output from %s, ",
116 					audmux_port_string((ptcr >> 17) & 0x7));
117 		else
118 			ret += snprintf(buf + ret, PAGE_SIZE - ret,
119 					"RxFS input, ");
120 
121 		if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
122 			ret += snprintf(buf + ret, PAGE_SIZE - ret,
123 					"RxClk output from %s",
124 					audmux_port_string((ptcr >> 12) & 0x7));
125 		else
126 			ret += snprintf(buf + ret, PAGE_SIZE - ret,
127 					"RxClk input");
128 	}
129 
130 	ret += snprintf(buf + ret, PAGE_SIZE - ret,
131 			"\nData received from %s\n",
132 			audmux_port_string((pdcr >> 13) & 0x7));
133 
134 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
135 
136 	kfree(buf);
137 
138 	return ret;
139 }
140 
141 static const struct file_operations audmux_debugfs_fops = {
142 	.open = simple_open,
143 	.read = audmux_read_file,
144 	.llseek = default_llseek,
145 };
146 
147 static void __init audmux_debugfs_init(void)
148 {
149 	int i;
150 	char buf[20];
151 
152 	audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
153 	if (!audmux_debugfs_root) {
154 		pr_warning("Failed to create AUDMUX debugfs root\n");
155 		return;
156 	}
157 
158 	for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
159 		snprintf(buf, sizeof(buf), "ssi%d", i);
160 		if (!debugfs_create_file(buf, 0444, audmux_debugfs_root,
161 					 (void *)i, &audmux_debugfs_fops))
162 			pr_warning("Failed to create AUDMUX port %d debugfs file\n",
163 				   i);
164 	}
165 }
166 
167 static void audmux_debugfs_remove(void)
168 {
169 	debugfs_remove_recursive(audmux_debugfs_root);
170 }
171 #else
172 static inline void audmux_debugfs_init(void)
173 {
174 }
175 
176 static inline void audmux_debugfs_remove(void)
177 {
178 }
179 #endif
180 
181 static enum imx_audmux_type {
182 	IMX21_AUDMUX,
183 	IMX31_AUDMUX,
184 } audmux_type;
185 
186 static struct platform_device_id imx_audmux_ids[] = {
187 	{
188 		.name = "imx21-audmux",
189 		.driver_data = IMX21_AUDMUX,
190 	}, {
191 		.name = "imx31-audmux",
192 		.driver_data = IMX31_AUDMUX,
193 	}, {
194 		/* sentinel */
195 	}
196 };
197 MODULE_DEVICE_TABLE(platform, imx_audmux_ids);
198 
199 static const struct of_device_id imx_audmux_dt_ids[] = {
200 	{ .compatible = "fsl,imx21-audmux", .data = &imx_audmux_ids[0], },
201 	{ .compatible = "fsl,imx31-audmux", .data = &imx_audmux_ids[1], },
202 	{ /* sentinel */ }
203 };
204 MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
205 
206 static const uint8_t port_mapping[] = {
207 	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
208 };
209 
210 int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
211 {
212 	if (audmux_type != IMX21_AUDMUX)
213 		return -EINVAL;
214 
215 	if (!audmux_base)
216 		return -ENOSYS;
217 
218 	if (port >= ARRAY_SIZE(port_mapping))
219 		return -EINVAL;
220 
221 	writel(pcr, audmux_base + port_mapping[port]);
222 
223 	return 0;
224 }
225 EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
226 
227 int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
228 		unsigned int pdcr)
229 {
230 	int ret;
231 
232 	if (audmux_type != IMX31_AUDMUX)
233 		return -EINVAL;
234 
235 	if (!audmux_base)
236 		return -ENOSYS;
237 
238 	if (audmux_clk) {
239 		ret = clk_prepare_enable(audmux_clk);
240 		if (ret)
241 			return ret;
242 	}
243 
244 	writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
245 	writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
246 
247 	if (audmux_clk)
248 		clk_disable_unprepare(audmux_clk);
249 
250 	return 0;
251 }
252 EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
253 
254 static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
255 		struct device_node *of_node)
256 {
257 	struct device_node *child;
258 
259 	for_each_available_child_of_node(of_node, child) {
260 		unsigned int port;
261 		unsigned int ptcr = 0;
262 		unsigned int pdcr = 0;
263 		unsigned int pcr = 0;
264 		unsigned int val;
265 		int ret;
266 		int i = 0;
267 
268 		ret = of_property_read_u32(child, "fsl,audmux-port", &port);
269 		if (ret) {
270 			dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%s\"\n",
271 					child->full_name);
272 			continue;
273 		}
274 		if (!of_property_read_bool(child, "fsl,port-config")) {
275 			dev_warn(&pdev->dev, "child node \"%s\" does not have property fsl,port-config\n",
276 					child->full_name);
277 			continue;
278 		}
279 
280 		for (i = 0; (ret = of_property_read_u32_index(child,
281 					"fsl,port-config", i, &val)) == 0;
282 				++i) {
283 			if (audmux_type == IMX31_AUDMUX) {
284 				if (i % 2)
285 					pdcr |= val;
286 				else
287 					ptcr |= val;
288 			} else {
289 				pcr |= val;
290 			}
291 		}
292 
293 		if (ret != -EOVERFLOW) {
294 			dev_err(&pdev->dev, "Failed to read u32 at index %d of child %s\n",
295 					i, child->full_name);
296 			continue;
297 		}
298 
299 		if (audmux_type == IMX31_AUDMUX) {
300 			if (i % 2) {
301 				dev_err(&pdev->dev, "One pdcr value is missing in child node %s\n",
302 						child->full_name);
303 				continue;
304 			}
305 			imx_audmux_v2_configure_port(port, ptcr, pdcr);
306 		} else {
307 			imx_audmux_v1_configure_port(port, pcr);
308 		}
309 	}
310 
311 	return 0;
312 }
313 
314 static int imx_audmux_probe(struct platform_device *pdev)
315 {
316 	struct resource *res;
317 	const struct of_device_id *of_id =
318 			of_match_device(imx_audmux_dt_ids, &pdev->dev);
319 
320 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
321 	audmux_base = devm_ioremap_resource(&pdev->dev, res);
322 	if (IS_ERR(audmux_base))
323 		return PTR_ERR(audmux_base);
324 
325 	audmux_clk = devm_clk_get(&pdev->dev, "audmux");
326 	if (IS_ERR(audmux_clk)) {
327 		dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
328 				PTR_ERR(audmux_clk));
329 		audmux_clk = NULL;
330 	}
331 
332 	if (of_id)
333 		pdev->id_entry = of_id->data;
334 	audmux_type = pdev->id_entry->driver_data;
335 	if (audmux_type == IMX31_AUDMUX)
336 		audmux_debugfs_init();
337 
338 	if (of_id)
339 		imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
340 
341 	return 0;
342 }
343 
344 static int imx_audmux_remove(struct platform_device *pdev)
345 {
346 	if (audmux_type == IMX31_AUDMUX)
347 		audmux_debugfs_remove();
348 
349 	return 0;
350 }
351 
352 static struct platform_driver imx_audmux_driver = {
353 	.probe		= imx_audmux_probe,
354 	.remove		= imx_audmux_remove,
355 	.id_table	= imx_audmux_ids,
356 	.driver	= {
357 		.name	= DRIVER_NAME,
358 		.owner	= THIS_MODULE,
359 		.of_match_table = imx_audmux_dt_ids,
360 	}
361 };
362 
363 static int __init imx_audmux_init(void)
364 {
365 	return platform_driver_register(&imx_audmux_driver);
366 }
367 subsys_initcall(imx_audmux_init);
368 
369 static void __exit imx_audmux_exit(void)
370 {
371 	platform_driver_unregister(&imx_audmux_driver);
372 }
373 module_exit(imx_audmux_exit);
374 
375 MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
376 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
377 MODULE_LICENSE("GPL v2");
378 MODULE_ALIAS("platform:" DRIVER_NAME);
379