xref: /openbmc/linux/sound/soc/fsl/imx-audmux.c (revision 8fcd94ad) 
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 = sysfs_emit(buf, "PDCR: %08x\nPTCR: %08x\n", pdcr, ptcr);
79 
80 	if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
81 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
82 				"TxFS output from %s, ",
83 				audmux_port_string((ptcr >> 27) & 0x7));
84 	else
85 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
86 				"TxFS input, ");
87 
88 	if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
89 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
90 				"TxClk output from %s",
91 				audmux_port_string((ptcr >> 22) & 0x7));
92 	else
93 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
94 				"TxClk input");
95 
96 	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
97 
98 	if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
99 		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
100 				"Port is symmetric");
101 	} else {
102 		if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
103 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
104 					"RxFS output from %s, ",
105 					audmux_port_string((ptcr >> 17) & 0x7));
106 		else
107 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
108 					"RxFS input, ");
109 
110 		if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
111 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
112 					"RxClk output from %s",
113 					audmux_port_string((ptcr >> 12) & 0x7));
114 		else
115 			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
116 					"RxClk input");
117 	}
118 
119 	ret += scnprintf(buf + ret, PAGE_SIZE - ret,
120 			"\nData received from %s\n",
121 			audmux_port_string((pdcr >> 13) & 0x7));
122 
123 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
124 
125 	kfree(buf);
126 
127 	return ret;
128 }
129 
130 static const struct file_operations audmux_debugfs_fops = {
131 	.open = simple_open,
132 	.read = audmux_read_file,
133 	.llseek = default_llseek,
134 };
135 
136 static void audmux_debugfs_init(void)
137 {
138 	uintptr_t i;
139 	char buf[20];
140 
141 	audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
142 
143 	for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
144 		snprintf(buf, sizeof(buf), "ssi%lu", i);
145 		debugfs_create_file(buf, 0444, audmux_debugfs_root,
146 				    (void *)i, &audmux_debugfs_fops);
147 	}
148 }
149 
150 static void audmux_debugfs_remove(void)
151 {
152 	debugfs_remove_recursive(audmux_debugfs_root);
153 }
154 #else
155 static inline void audmux_debugfs_init(void)
156 {
157 }
158 
159 static inline void audmux_debugfs_remove(void)
160 {
161 }
162 #endif
163 
164 static enum imx_audmux_type {
165 	IMX21_AUDMUX,
166 	IMX31_AUDMUX,
167 } audmux_type;
168 
169 static const struct of_device_id imx_audmux_dt_ids[] = {
170 	{ .compatible = "fsl,imx21-audmux", .data = (void *)IMX21_AUDMUX, },
171 	{ .compatible = "fsl,imx31-audmux", .data = (void *)IMX31_AUDMUX, },
172 	{ /* sentinel */ }
173 };
174 MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
175 
176 static const uint8_t port_mapping[] = {
177 	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
178 };
179 
180 int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
181 {
182 	if (audmux_type != IMX21_AUDMUX)
183 		return -EINVAL;
184 
185 	if (!audmux_base)
186 		return -ENOSYS;
187 
188 	if (port >= ARRAY_SIZE(port_mapping))
189 		return -EINVAL;
190 
191 	writel(pcr, audmux_base + port_mapping[port]);
192 
193 	return 0;
194 }
195 EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
196 
197 int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
198 		unsigned int pdcr)
199 {
200 	int ret;
201 
202 	if (audmux_type != IMX31_AUDMUX)
203 		return -EINVAL;
204 
205 	if (!audmux_base)
206 		return -ENOSYS;
207 
208 	ret = clk_prepare_enable(audmux_clk);
209 	if (ret)
210 		return ret;
211 
212 	writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
213 	writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
214 
215 	clk_disable_unprepare(audmux_clk);
216 
217 	return 0;
218 }
219 EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
220 
221 static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
222 		struct device_node *of_node)
223 {
224 	struct device_node *child;
225 
226 	for_each_available_child_of_node(of_node, child) {
227 		unsigned int port;
228 		unsigned int ptcr = 0;
229 		unsigned int pdcr = 0;
230 		unsigned int pcr = 0;
231 		unsigned int val;
232 		int ret;
233 		int i = 0;
234 
235 		ret = of_property_read_u32(child, "fsl,audmux-port", &port);
236 		if (ret) {
237 			dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%pOF\"\n",
238 					child);
239 			continue;
240 		}
241 		if (!of_property_read_bool(child, "fsl,port-config")) {
242 			dev_warn(&pdev->dev, "child node \"%pOF\" does not have property fsl,port-config\n",
243 					child);
244 			continue;
245 		}
246 
247 		for (i = 0; (ret = of_property_read_u32_index(child,
248 					"fsl,port-config", i, &val)) == 0;
249 				++i) {
250 			if (audmux_type == IMX31_AUDMUX) {
251 				if (i % 2)
252 					pdcr |= val;
253 				else
254 					ptcr |= val;
255 			} else {
256 				pcr |= val;
257 			}
258 		}
259 
260 		if (ret != -EOVERFLOW) {
261 			dev_err(&pdev->dev, "Failed to read u32 at index %d of child %pOF\n",
262 					i, child);
263 			continue;
264 		}
265 
266 		if (audmux_type == IMX31_AUDMUX) {
267 			if (i % 2) {
268 				dev_err(&pdev->dev, "One pdcr value is missing in child node %pOF\n",
269 						child);
270 				continue;
271 			}
272 			imx_audmux_v2_configure_port(port, ptcr, pdcr);
273 		} else {
274 			imx_audmux_v1_configure_port(port, pcr);
275 		}
276 	}
277 
278 	return 0;
279 }
280 
281 static int imx_audmux_probe(struct platform_device *pdev)
282 {
283 	audmux_base = devm_platform_ioremap_resource(pdev, 0);
284 	if (IS_ERR(audmux_base))
285 		return PTR_ERR(audmux_base);
286 
287 	audmux_clk = devm_clk_get(&pdev->dev, "audmux");
288 	if (IS_ERR(audmux_clk)) {
289 		dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
290 				PTR_ERR(audmux_clk));
291 		audmux_clk = NULL;
292 	}
293 
294 	audmux_type = (uintptr_t)of_device_get_match_data(&pdev->dev);
295 
296 	switch (audmux_type) {
297 	case IMX31_AUDMUX:
298 		audmux_debugfs_init();
299 		reg_max = 14;
300 		break;
301 	case IMX21_AUDMUX:
302 		reg_max = 6;
303 		break;
304 	default:
305 		dev_err(&pdev->dev, "unsupported version!\n");
306 		return -EINVAL;
307 	}
308 
309 	regcache = devm_kzalloc(&pdev->dev, sizeof(u32) * reg_max, GFP_KERNEL);
310 	if (!regcache)
311 		return -ENOMEM;
312 
313 	imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
314 
315 	return 0;
316 }
317 
318 static void imx_audmux_remove(struct platform_device *pdev)
319 {
320 	if (audmux_type == IMX31_AUDMUX)
321 		audmux_debugfs_remove();
322 }
323 
324 #ifdef CONFIG_PM_SLEEP
325 static int imx_audmux_suspend(struct device *dev)
326 {
327 	int i;
328 
329 	clk_prepare_enable(audmux_clk);
330 
331 	for (i = 0; i < reg_max; i++)
332 		regcache[i] = readl(audmux_base + i * 4);
333 
334 	clk_disable_unprepare(audmux_clk);
335 
336 	return 0;
337 }
338 
339 static int imx_audmux_resume(struct device *dev)
340 {
341 	int i;
342 
343 	clk_prepare_enable(audmux_clk);
344 
345 	for (i = 0; i < reg_max; i++)
346 		writel(regcache[i], audmux_base + i * 4);
347 
348 	clk_disable_unprepare(audmux_clk);
349 
350 	return 0;
351 }
352 #endif /* CONFIG_PM_SLEEP */
353 
354 static const struct dev_pm_ops imx_audmux_pm = {
355 	SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
356 };
357 
358 static struct platform_driver imx_audmux_driver = {
359 	.probe		= imx_audmux_probe,
360 	.remove_new	= imx_audmux_remove,
361 	.driver	= {
362 		.name	= DRIVER_NAME,
363 		.pm = &imx_audmux_pm,
364 		.of_match_table = imx_audmux_dt_ids,
365 	}
366 };
367 
368 static int __init imx_audmux_init(void)
369 {
370 	return platform_driver_register(&imx_audmux_driver);
371 }
372 subsys_initcall(imx_audmux_init);
373 
374 static void __exit imx_audmux_exit(void)
375 {
376 	platform_driver_unregister(&imx_audmux_driver);
377 }
378 module_exit(imx_audmux_exit);
379 
380 MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
381 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
382 MODULE_LICENSE("GPL v2");
383 MODULE_ALIAS("platform:" DRIVER_NAME);
384