xref: /openbmc/linux/sound/soc/fsl/imx-audmux.c (revision 3b73c45e) 
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright 2012 Freescale Semiconductor, Inc.
4 // Copyright 2012 Linaro Ltd.
5 // Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
6 //
7 // Initial development of this code was funded by
8 // Phytec Messtechnik GmbH, https://www.phytec.de
9 
10 #include <linux/clk.h>
11 #include <linux/debugfs.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 
20 #include "imx-audmux.h"
21 
22 #define DRIVER_NAME "imx-audmux"
23 
24 static struct clk *audmux_clk;
25 static void __iomem *audmux_base;
26 static u32 *regcache;
27 static u32 reg_max;
28 
29 #define IMX_AUDMUX_V2_PTCR(x)		((x) * 8)
30 #define IMX_AUDMUX_V2_PDCR(x)		((x) * 8 + 4)
31 
32 #ifdef CONFIG_DEBUG_FS
33 static struct dentry *audmux_debugfs_root;
34 
35 /* There is an annoying discontinuity in the SSI numbering with regard
36  * to the Linux number of the devices */
37 static const char *audmux_port_string(int port)
38 {
39 	switch (port) {
40 	case MX31_AUDMUX_PORT1_SSI0:
41 		return "imx-ssi.0";
42 	case MX31_AUDMUX_PORT2_SSI1:
43 		return "imx-ssi.1";
44 	case MX31_AUDMUX_PORT3_SSI_PINS_3:
45 		return "SSI3";
46 	case MX31_AUDMUX_PORT4_SSI_PINS_4:
47 		return "SSI4";
48 	case MX31_AUDMUX_PORT5_SSI_PINS_5:
49 		return "SSI5";
50 	case MX31_AUDMUX_PORT6_SSI_PINS_6:
51 		return "SSI6";
52 	default:
53 		return "UNKNOWN";
54 	}
55 }
56 
57 static ssize_t audmux_read_file(struct file *file, char __user *user_buf,
58 				size_t count, loff_t *ppos)
59 {
60 	ssize_t ret;
61 	char *buf;
62 	uintptr_t port = (uintptr_t)file->private_data;
63 	u32 pdcr, ptcr;
64 
65 	ret = clk_prepare_enable(audmux_clk);
66 	if (ret)
67 		return ret;
68 
69 	ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
70 	pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
71 
72 	clk_disable_unprepare(audmux_clk);
73 
74 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
75 	if (!buf)
76 		return -ENOMEM;
77 
78 	ret = scnprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
79 		       pdcr, ptcr);
80 
81 	if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
82 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
83 				"TxFS output from %s, ",
84 				audmux_port_string((ptcr >> 27) & 0x7));
85 	else
86 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
87 				"TxFS input, ");
88 
89 	if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
90 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
91 				"TxClk output from %s",
92 				audmux_port_string((ptcr >> 22) & 0x7));
93 	else
94 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
95 				"TxClk input");
96 
97 	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
98 
99 	if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
100 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
101 				"Port is symmetric");
102 	} else {
103 		if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
104 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
105 					"RxFS output from %s, ",
106 					audmux_port_string((ptcr >> 17) & 0x7));
107 		else
108 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
109 					"RxFS input, ");
110 
111 		if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
112 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
113 					"RxClk output from %s",
114 					audmux_port_string((ptcr >> 12) & 0x7));
115 		else
116 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
117 					"RxClk input");
118 	}
119 
120 	ret += scnprintf(buf + ret, PAGE_SIZE - ret,
121 			"\nData received from %s\n",
122 			audmux_port_string((pdcr >> 13) & 0x7));
123 
124 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
125 
126 	kfree(buf);
127 
128 	return ret;
129 }
130 
131 static const struct file_operations audmux_debugfs_fops = {
132 	.open = simple_open,
133 	.read = audmux_read_file,
134 	.llseek = default_llseek,
135 };
136 
137 static void audmux_debugfs_init(void)
138 {
139 	uintptr_t i;
140 	char buf[20];
141 
142 	audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
143 
144 	for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
145 		snprintf(buf, sizeof(buf), "ssi%lu", i);
146 		debugfs_create_file(buf, 0444, audmux_debugfs_root,
147 				    (void *)i, &audmux_debugfs_fops);
148 	}
149 }
150 
151 static void audmux_debugfs_remove(void)
152 {
153 	debugfs_remove_recursive(audmux_debugfs_root);
154 }
155 #else
156 static inline void audmux_debugfs_init(void)
157 {
158 }
159 
160 static inline void audmux_debugfs_remove(void)
161 {
162 }
163 #endif
164 
165 static enum imx_audmux_type {
166 	IMX21_AUDMUX,
167 	IMX31_AUDMUX,
168 } audmux_type;
169 
170 static const struct of_device_id imx_audmux_dt_ids[] = {
171 	{ .compatible = "fsl,imx21-audmux", .data = (void *)IMX21_AUDMUX, },
172 	{ .compatible = "fsl,imx31-audmux", .data = (void *)IMX31_AUDMUX, },
173 	{ /* sentinel */ }
174 };
175 MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
176 
177 static const uint8_t port_mapping[] = {
178 	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
179 };
180 
181 int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
182 {
183 	if (audmux_type != IMX21_AUDMUX)
184 		return -EINVAL;
185 
186 	if (!audmux_base)
187 		return -ENOSYS;
188 
189 	if (port >= ARRAY_SIZE(port_mapping))
190 		return -EINVAL;
191 
192 	writel(pcr, audmux_base + port_mapping[port]);
193 
194 	return 0;
195 }
196 EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
197 
198 int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
199 		unsigned int pdcr)
200 {
201 	int ret;
202 
203 	if (audmux_type != IMX31_AUDMUX)
204 		return -EINVAL;
205 
206 	if (!audmux_base)
207 		return -ENOSYS;
208 
209 	ret = clk_prepare_enable(audmux_clk);
210 	if (ret)
211 		return ret;
212 
213 	writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
214 	writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
215 
216 	clk_disable_unprepare(audmux_clk);
217 
218 	return 0;
219 }
220 EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
221 
222 static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
223 		struct device_node *of_node)
224 {
225 	struct device_node *child;
226 
227 	for_each_available_child_of_node(of_node, child) {
228 		unsigned int port;
229 		unsigned int ptcr = 0;
230 		unsigned int pdcr = 0;
231 		unsigned int pcr = 0;
232 		unsigned int val;
233 		int ret;
234 		int i = 0;
235 
236 		ret = of_property_read_u32(child, "fsl,audmux-port", &port);
237 		if (ret) {
238 			dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%pOF\"\n",
239 					child);
240 			continue;
241 		}
242 		if (!of_property_read_bool(child, "fsl,port-config")) {
243 			dev_warn(&pdev->dev, "child node \"%pOF\" does not have property fsl,port-config\n",
244 					child);
245 			continue;
246 		}
247 
248 		for (i = 0; (ret = of_property_read_u32_index(child,
249 					"fsl,port-config", i, &val)) == 0;
250 				++i) {
251 			if (audmux_type == IMX31_AUDMUX) {
252 				if (i % 2)
253 					pdcr |= val;
254 				else
255 					ptcr |= val;
256 			} else {
257 				pcr |= val;
258 			}
259 		}
260 
261 		if (ret != -EOVERFLOW) {
262 			dev_err(&pdev->dev, "Failed to read u32 at index %d of child %pOF\n",
263 					i, child);
264 			continue;
265 		}
266 
267 		if (audmux_type == IMX31_AUDMUX) {
268 			if (i % 2) {
269 				dev_err(&pdev->dev, "One pdcr value is missing in child node %pOF\n",
270 						child);
271 				continue;
272 			}
273 			imx_audmux_v2_configure_port(port, ptcr, pdcr);
274 		} else {
275 			imx_audmux_v1_configure_port(port, pcr);
276 		}
277 	}
278 
279 	return 0;
280 }
281 
282 static int imx_audmux_probe(struct platform_device *pdev)
283 {
284 	audmux_base = devm_platform_ioremap_resource(pdev, 0);
285 	if (IS_ERR(audmux_base))
286 		return PTR_ERR(audmux_base);
287 
288 	audmux_clk = devm_clk_get(&pdev->dev, "audmux");
289 	if (IS_ERR(audmux_clk)) {
290 		dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
291 				PTR_ERR(audmux_clk));
292 		audmux_clk = NULL;
293 	}
294 
295 	audmux_type = (uintptr_t)of_device_get_match_data(&pdev->dev);
296 
297 	switch (audmux_type) {
298 	case IMX31_AUDMUX:
299 		audmux_debugfs_init();
300 		reg_max = 14;
301 		break;
302 	case IMX21_AUDMUX:
303 		reg_max = 6;
304 		break;
305 	default:
306 		dev_err(&pdev->dev, "unsupported version!\n");
307 		return -EINVAL;
308 	}
309 
310 	regcache = devm_kzalloc(&pdev->dev, sizeof(u32) * reg_max, GFP_KERNEL);
311 	if (!regcache)
312 		return -ENOMEM;
313 
314 	imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
315 
316 	return 0;
317 }
318 
319 static int imx_audmux_remove(struct platform_device *pdev)
320 {
321 	if (audmux_type == IMX31_AUDMUX)
322 		audmux_debugfs_remove();
323 
324 	return 0;
325 }
326 
327 #ifdef CONFIG_PM_SLEEP
328 static int imx_audmux_suspend(struct device *dev)
329 {
330 	int i;
331 
332 	clk_prepare_enable(audmux_clk);
333 
334 	for (i = 0; i < reg_max; i++)
335 		regcache[i] = readl(audmux_base + i * 4);
336 
337 	clk_disable_unprepare(audmux_clk);
338 
339 	return 0;
340 }
341 
342 static int imx_audmux_resume(struct device *dev)
343 {
344 	int i;
345 
346 	clk_prepare_enable(audmux_clk);
347 
348 	for (i = 0; i < reg_max; i++)
349 		writel(regcache[i], audmux_base + i * 4);
350 
351 	clk_disable_unprepare(audmux_clk);
352 
353 	return 0;
354 }
355 #endif /* CONFIG_PM_SLEEP */
356 
357 static const struct dev_pm_ops imx_audmux_pm = {
358 	SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
359 };
360 
361 static struct platform_driver imx_audmux_driver = {
362 	.probe		= imx_audmux_probe,
363 	.remove		= imx_audmux_remove,
364 	.driver	= {
365 		.name	= DRIVER_NAME,
366 		.pm = &imx_audmux_pm,
367 		.of_match_table = imx_audmux_dt_ids,
368 	}
369 };
370 
371 static int __init imx_audmux_init(void)
372 {
373 	return platform_driver_register(&imx_audmux_driver);
374 }
375 subsys_initcall(imx_audmux_init);
376 
377 static void __exit imx_audmux_exit(void)
378 {
379 	platform_driver_unregister(&imx_audmux_driver);
380 }
381 module_exit(imx_audmux_exit);
382 
383 MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
384 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
385 MODULE_LICENSE("GPL v2");
386 MODULE_ALIAS("platform:" DRIVER_NAME);
387