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	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
130static const struct file_operations audmux_debugfs_fops = {
131	.open = simple_open,
132	.read = audmux_read_file,
133	.llseek = default_llseek,
134};
135
136static 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
150static void audmux_debugfs_remove(void)
151{
152	debugfs_remove_recursive(audmux_debugfs_root);
153}
154#else
155static inline void audmux_debugfs_init(void)
156{
157}
158
159static inline void audmux_debugfs_remove(void)
160{
161}
162#endif
163
164static enum imx_audmux_type {
165	IMX21_AUDMUX,
166	IMX31_AUDMUX,
167} audmux_type;
168
169static 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};
174MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
175
176static const uint8_t port_mapping[] = {
177	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
178};
179
180int 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}
195EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
196
197int 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}
219EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
220
221static 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
281static 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
318static 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
325static 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
339static 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
354static const struct dev_pm_ops imx_audmux_pm = {
355	SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
356};
357
358static 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
368static int __init imx_audmux_init(void)
369{
370	return platform_driver_register(&imx_audmux_driver);
371}
372subsys_initcall(imx_audmux_init);
373
374static void __exit imx_audmux_exit(void)
375{
376	platform_driver_unregister(&imx_audmux_driver);
377}
378module_exit(imx_audmux_exit);
379
380MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
381MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
382MODULE_LICENSE("GPL v2");
383MODULE_ALIAS("platform:" DRIVER_NAME);
384