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