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
24static struct clk *audmux_clk;
25static void __iomem *audmux_base;
26static u32 *regcache;
27static 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
33static 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 */
37static 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
57static 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	if (audmux_clk) {
66		ret = clk_prepare_enable(audmux_clk);
67		if (ret)
68			return ret;
69	}
70
71	ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
72	pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
73
74	if (audmux_clk)
75		clk_disable_unprepare(audmux_clk);
76
77	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
78	if (!buf)
79		return -ENOMEM;
80
81	ret = scnprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
82		       pdcr, ptcr);
83
84	if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
85		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
86				"TxFS output from %s, ",
87				audmux_port_string((ptcr >> 27) & 0x7));
88	else
89		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
90				"TxFS input, ");
91
92	if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
93		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
94				"TxClk output from %s",
95				audmux_port_string((ptcr >> 22) & 0x7));
96	else
97		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
98				"TxClk input");
99
100	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
101
102	if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
103		ret += scnprintf(buf + ret, PAGE_SIZE - ret,
104				"Port is symmetric");
105	} else {
106		if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
107			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
108					"RxFS output from %s, ",
109					audmux_port_string((ptcr >> 17) & 0x7));
110		else
111			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
112					"RxFS input, ");
113
114		if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
115			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
116					"RxClk output from %s",
117					audmux_port_string((ptcr >> 12) & 0x7));
118		else
119			ret += scnprintf(buf + ret, PAGE_SIZE - ret,
120					"RxClk input");
121	}
122
123	ret += scnprintf(buf + ret, PAGE_SIZE - ret,
124			"\nData received from %s\n",
125			audmux_port_string((pdcr >> 13) & 0x7));
126
127	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
128
129	kfree(buf);
130
131	return ret;
132}
133
134static const struct file_operations audmux_debugfs_fops = {
135	.open = simple_open,
136	.read = audmux_read_file,
137	.llseek = default_llseek,
138};
139
140static void audmux_debugfs_init(void)
141{
142	uintptr_t i;
143	char buf[20];
144
145	audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
146
147	for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
148		snprintf(buf, sizeof(buf), "ssi%lu", i);
149		debugfs_create_file(buf, 0444, audmux_debugfs_root,
150				    (void *)i, &audmux_debugfs_fops);
151	}
152}
153
154static void audmux_debugfs_remove(void)
155{
156	debugfs_remove_recursive(audmux_debugfs_root);
157}
158#else
159static inline void audmux_debugfs_init(void)
160{
161}
162
163static inline void audmux_debugfs_remove(void)
164{
165}
166#endif
167
168static enum imx_audmux_type {
169	IMX21_AUDMUX,
170	IMX31_AUDMUX,
171} audmux_type;
172
173static const struct platform_device_id imx_audmux_ids[] = {
174	{
175		.name = "imx21-audmux",
176		.driver_data = IMX21_AUDMUX,
177	}, {
178		.name = "imx31-audmux",
179		.driver_data = IMX31_AUDMUX,
180	}, {
181		/* sentinel */
182	}
183};
184MODULE_DEVICE_TABLE(platform, imx_audmux_ids);
185
186static const struct of_device_id imx_audmux_dt_ids[] = {
187	{ .compatible = "fsl,imx21-audmux", .data = &imx_audmux_ids[0], },
188	{ .compatible = "fsl,imx31-audmux", .data = &imx_audmux_ids[1], },
189	{ /* sentinel */ }
190};
191MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
192
193static const uint8_t port_mapping[] = {
194	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
195};
196
197int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
198{
199	if (audmux_type != IMX21_AUDMUX)
200		return -EINVAL;
201
202	if (!audmux_base)
203		return -ENOSYS;
204
205	if (port >= ARRAY_SIZE(port_mapping))
206		return -EINVAL;
207
208	writel(pcr, audmux_base + port_mapping[port]);
209
210	return 0;
211}
212EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
213
214int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
215		unsigned int pdcr)
216{
217	int ret;
218
219	if (audmux_type != IMX31_AUDMUX)
220		return -EINVAL;
221
222	if (!audmux_base)
223		return -ENOSYS;
224
225	if (audmux_clk) {
226		ret = clk_prepare_enable(audmux_clk);
227		if (ret)
228			return ret;
229	}
230
231	writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
232	writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
233
234	if (audmux_clk)
235		clk_disable_unprepare(audmux_clk);
236
237	return 0;
238}
239EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
240
241static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
242		struct device_node *of_node)
243{
244	struct device_node *child;
245
246	for_each_available_child_of_node(of_node, child) {
247		unsigned int port;
248		unsigned int ptcr = 0;
249		unsigned int pdcr = 0;
250		unsigned int pcr = 0;
251		unsigned int val;
252		int ret;
253		int i = 0;
254
255		ret = of_property_read_u32(child, "fsl,audmux-port", &port);
256		if (ret) {
257			dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%pOF\"\n",
258					child);
259			continue;
260		}
261		if (!of_property_read_bool(child, "fsl,port-config")) {
262			dev_warn(&pdev->dev, "child node \"%pOF\" does not have property fsl,port-config\n",
263					child);
264			continue;
265		}
266
267		for (i = 0; (ret = of_property_read_u32_index(child,
268					"fsl,port-config", i, &val)) == 0;
269				++i) {
270			if (audmux_type == IMX31_AUDMUX) {
271				if (i % 2)
272					pdcr |= val;
273				else
274					ptcr |= val;
275			} else {
276				pcr |= val;
277			}
278		}
279
280		if (ret != -EOVERFLOW) {
281			dev_err(&pdev->dev, "Failed to read u32 at index %d of child %pOF\n",
282					i, child);
283			continue;
284		}
285
286		if (audmux_type == IMX31_AUDMUX) {
287			if (i % 2) {
288				dev_err(&pdev->dev, "One pdcr value is missing in child node %pOF\n",
289						child);
290				continue;
291			}
292			imx_audmux_v2_configure_port(port, ptcr, pdcr);
293		} else {
294			imx_audmux_v1_configure_port(port, pcr);
295		}
296	}
297
298	return 0;
299}
300
301static int imx_audmux_probe(struct platform_device *pdev)
302{
303	const struct of_device_id *of_id =
304			of_match_device(imx_audmux_dt_ids, &pdev->dev);
305
306	audmux_base = devm_platform_ioremap_resource(pdev, 0);
307	if (IS_ERR(audmux_base))
308		return PTR_ERR(audmux_base);
309
310	audmux_clk = devm_clk_get(&pdev->dev, "audmux");
311	if (IS_ERR(audmux_clk)) {
312		dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
313				PTR_ERR(audmux_clk));
314		audmux_clk = NULL;
315	}
316
317	if (of_id)
318		pdev->id_entry = of_id->data;
319	audmux_type = pdev->id_entry->driver_data;
320
321	switch (audmux_type) {
322	case IMX31_AUDMUX:
323		audmux_debugfs_init();
324		reg_max = 14;
325		break;
326	case IMX21_AUDMUX:
327		reg_max = 6;
328		break;
329	default:
330		dev_err(&pdev->dev, "unsupported version!\n");
331		return -EINVAL;
332	}
333
334	regcache = devm_kzalloc(&pdev->dev, sizeof(u32) * reg_max, GFP_KERNEL);
335	if (!regcache)
336		return -ENOMEM;
337
338	if (of_id)
339		imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
340
341	return 0;
342}
343
344static 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#ifdef CONFIG_PM_SLEEP
353static int imx_audmux_suspend(struct device *dev)
354{
355	int i;
356
357	clk_prepare_enable(audmux_clk);
358
359	for (i = 0; i < reg_max; i++)
360		regcache[i] = readl(audmux_base + i * 4);
361
362	clk_disable_unprepare(audmux_clk);
363
364	return 0;
365}
366
367static int imx_audmux_resume(struct device *dev)
368{
369	int i;
370
371	clk_prepare_enable(audmux_clk);
372
373	for (i = 0; i < reg_max; i++)
374		writel(regcache[i], audmux_base + i * 4);
375
376	clk_disable_unprepare(audmux_clk);
377
378	return 0;
379}
380#endif /* CONFIG_PM_SLEEP */
381
382static const struct dev_pm_ops imx_audmux_pm = {
383	SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
384};
385
386static struct platform_driver imx_audmux_driver = {
387	.probe		= imx_audmux_probe,
388	.remove		= imx_audmux_remove,
389	.id_table	= imx_audmux_ids,
390	.driver	= {
391		.name	= DRIVER_NAME,
392		.pm = &imx_audmux_pm,
393		.of_match_table = imx_audmux_dt_ids,
394	}
395};
396
397static int __init imx_audmux_init(void)
398{
399	return platform_driver_register(&imx_audmux_driver);
400}
401subsys_initcall(imx_audmux_init);
402
403static void __exit imx_audmux_exit(void)
404{
405	platform_driver_unregister(&imx_audmux_driver);
406}
407module_exit(imx_audmux_exit);
408
409MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
410MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
411MODULE_LICENSE("GPL v2");
412MODULE_ALIAS("platform:" DRIVER_NAME);
413