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
23static struct clk *audmux_clk;
24static void __iomem *audmux_base;
25static u32 *regcache;
26static 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
32static 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 */
36static 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
56static 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
129static const struct file_operations audmux_debugfs_fops = {
130	.open = simple_open,
131	.read = audmux_read_file,
132	.llseek = default_llseek,
133};
134
135static 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
149static void audmux_debugfs_remove(void)
150{
151	debugfs_remove_recursive(audmux_debugfs_root);
152}
153#else
154static inline void audmux_debugfs_init(void)
155{
156}
157
158static inline void audmux_debugfs_remove(void)
159{
160}
161#endif
162
163static enum imx_audmux_type {
164	IMX21_AUDMUX,
165	IMX31_AUDMUX,
166} audmux_type;
167
168static 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};
173MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
174
175static const uint8_t port_mapping[] = {
176	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
177};
178
179int 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}
194EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
195
196int 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}
218EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
219
220static 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
280static 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
317static 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
324static 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
338static 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
353static const struct dev_pm_ops imx_audmux_pm = {
354	SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
355};
356
357static 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
367static int __init imx_audmux_init(void)
368{
369	return platform_driver_register(&imx_audmux_driver);
370}
371subsys_initcall(imx_audmux_init);
372
373static void __exit imx_audmux_exit(void)
374{
375	platform_driver_unregister(&imx_audmux_driver);
376}
377module_exit(imx_audmux_exit);
378
379MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
380MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
381MODULE_LICENSE("GPL v2");
382MODULE_ALIAS("platform:" DRIVER_NAME);
383