1/*
2 * Copyright 2012 Freescale Semiconductor, Inc.
3 * Copyright 2012 Linaro Ltd.
4 * Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
5 *
6 * Initial development of this code was funded by
7 * Phytec Messtechnik GmbH, http://www.phytec.de
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 * GNU General Public License for more details.
18 */
19
20#include <linux/clk.h>
21#include <linux/debugfs.h>
22#include <linux/err.h>
23#include <linux/io.h>
24#include <linux/module.h>
25#include <linux/of.h>
26#include <linux/of_device.h>
27#include <linux/platform_device.h>
28#include <linux/slab.h>
29
30#include "imx-audmux.h"
31
32#define DRIVER_NAME "imx-audmux"
33
34static struct clk *audmux_clk;
35static void __iomem *audmux_base;
36
37#define IMX_AUDMUX_V2_PTCR(x)		((x) * 8)
38#define IMX_AUDMUX_V2_PDCR(x)		((x) * 8 + 4)
39
40#ifdef CONFIG_DEBUG_FS
41static struct dentry *audmux_debugfs_root;
42
43/* There is an annoying discontinuity in the SSI numbering with regard
44 * to the Linux number of the devices */
45static const char *audmux_port_string(int port)
46{
47	switch (port) {
48	case MX31_AUDMUX_PORT1_SSI0:
49		return "imx-ssi.0";
50	case MX31_AUDMUX_PORT2_SSI1:
51		return "imx-ssi.1";
52	case MX31_AUDMUX_PORT3_SSI_PINS_3:
53		return "SSI3";
54	case MX31_AUDMUX_PORT4_SSI_PINS_4:
55		return "SSI4";
56	case MX31_AUDMUX_PORT5_SSI_PINS_5:
57		return "SSI5";
58	case MX31_AUDMUX_PORT6_SSI_PINS_6:
59		return "SSI6";
60	default:
61		return "UNKNOWN";
62	}
63}
64
65static ssize_t audmux_read_file(struct file *file, char __user *user_buf,
66				size_t count, loff_t *ppos)
67{
68	ssize_t ret;
69	char *buf;
70	uintptr_t port = (uintptr_t)file->private_data;
71	u32 pdcr, ptcr;
72
73	if (audmux_clk) {
74		ret = clk_prepare_enable(audmux_clk);
75		if (ret)
76			return ret;
77	}
78
79	ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
80	pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
81
82	if (audmux_clk)
83		clk_disable_unprepare(audmux_clk);
84
85	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
86	if (!buf)
87		return -ENOMEM;
88
89	ret = snprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
90		       pdcr, ptcr);
91
92	if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
93		ret += snprintf(buf + ret, PAGE_SIZE - ret,
94				"TxFS output from %s, ",
95				audmux_port_string((ptcr >> 27) & 0x7));
96	else
97		ret += snprintf(buf + ret, PAGE_SIZE - ret,
98				"TxFS input, ");
99
100	if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
101		ret += snprintf(buf + ret, PAGE_SIZE - ret,
102				"TxClk output from %s",
103				audmux_port_string((ptcr >> 22) & 0x7));
104	else
105		ret += snprintf(buf + ret, PAGE_SIZE - ret,
106				"TxClk input");
107
108	ret += snprintf(buf + ret, PAGE_SIZE - ret, "\n");
109
110	if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
111		ret += snprintf(buf + ret, PAGE_SIZE - ret,
112				"Port is symmetric");
113	} else {
114		if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
115			ret += snprintf(buf + ret, PAGE_SIZE - ret,
116					"RxFS output from %s, ",
117					audmux_port_string((ptcr >> 17) & 0x7));
118		else
119			ret += snprintf(buf + ret, PAGE_SIZE - ret,
120					"RxFS input, ");
121
122		if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
123			ret += snprintf(buf + ret, PAGE_SIZE - ret,
124					"RxClk output from %s",
125					audmux_port_string((ptcr >> 12) & 0x7));
126		else
127			ret += snprintf(buf + ret, PAGE_SIZE - ret,
128					"RxClk input");
129	}
130
131	ret += snprintf(buf + ret, PAGE_SIZE - ret,
132			"\nData received from %s\n",
133			audmux_port_string((pdcr >> 13) & 0x7));
134
135	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
136
137	kfree(buf);
138
139	return ret;
140}
141
142static const struct file_operations audmux_debugfs_fops = {
143	.open = simple_open,
144	.read = audmux_read_file,
145	.llseek = default_llseek,
146};
147
148static void audmux_debugfs_init(void)
149{
150	uintptr_t i;
151	char buf[20];
152
153	audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
154	if (!audmux_debugfs_root) {
155		pr_warning("Failed to create AUDMUX debugfs root\n");
156		return;
157	}
158
159	for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
160		snprintf(buf, sizeof(buf), "ssi%lu", i);
161		if (!debugfs_create_file(buf, 0444, audmux_debugfs_root,
162					 (void *)i, &audmux_debugfs_fops))
163			pr_warning("Failed to create AUDMUX port %lu debugfs file\n",
164				   i);
165	}
166}
167
168static void audmux_debugfs_remove(void)
169{
170	debugfs_remove_recursive(audmux_debugfs_root);
171}
172#else
173static inline void audmux_debugfs_init(void)
174{
175}
176
177static inline void audmux_debugfs_remove(void)
178{
179}
180#endif
181
182static enum imx_audmux_type {
183	IMX21_AUDMUX,
184	IMX31_AUDMUX,
185} audmux_type;
186
187static struct platform_device_id imx_audmux_ids[] = {
188	{
189		.name = "imx21-audmux",
190		.driver_data = IMX21_AUDMUX,
191	}, {
192		.name = "imx31-audmux",
193		.driver_data = IMX31_AUDMUX,
194	}, {
195		/* sentinel */
196	}
197};
198MODULE_DEVICE_TABLE(platform, imx_audmux_ids);
199
200static const struct of_device_id imx_audmux_dt_ids[] = {
201	{ .compatible = "fsl,imx21-audmux", .data = &imx_audmux_ids[0], },
202	{ .compatible = "fsl,imx31-audmux", .data = &imx_audmux_ids[1], },
203	{ /* sentinel */ }
204};
205MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
206
207static const uint8_t port_mapping[] = {
208	0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
209};
210
211int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
212{
213	if (audmux_type != IMX21_AUDMUX)
214		return -EINVAL;
215
216	if (!audmux_base)
217		return -ENOSYS;
218
219	if (port >= ARRAY_SIZE(port_mapping))
220		return -EINVAL;
221
222	writel(pcr, audmux_base + port_mapping[port]);
223
224	return 0;
225}
226EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
227
228int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
229		unsigned int pdcr)
230{
231	int ret;
232
233	if (audmux_type != IMX31_AUDMUX)
234		return -EINVAL;
235
236	if (!audmux_base)
237		return -ENOSYS;
238
239	if (audmux_clk) {
240		ret = clk_prepare_enable(audmux_clk);
241		if (ret)
242			return ret;
243	}
244
245	writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
246	writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
247
248	if (audmux_clk)
249		clk_disable_unprepare(audmux_clk);
250
251	return 0;
252}
253EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
254
255static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
256		struct device_node *of_node)
257{
258	struct device_node *child;
259
260	for_each_available_child_of_node(of_node, child) {
261		unsigned int port;
262		unsigned int ptcr = 0;
263		unsigned int pdcr = 0;
264		unsigned int pcr = 0;
265		unsigned int val;
266		int ret;
267		int i = 0;
268
269		ret = of_property_read_u32(child, "fsl,audmux-port", &port);
270		if (ret) {
271			dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%s\"\n",
272					child->full_name);
273			continue;
274		}
275		if (!of_property_read_bool(child, "fsl,port-config")) {
276			dev_warn(&pdev->dev, "child node \"%s\" does not have property fsl,port-config\n",
277					child->full_name);
278			continue;
279		}
280
281		for (i = 0; (ret = of_property_read_u32_index(child,
282					"fsl,port-config", i, &val)) == 0;
283				++i) {
284			if (audmux_type == IMX31_AUDMUX) {
285				if (i % 2)
286					pdcr |= val;
287				else
288					ptcr |= val;
289			} else {
290				pcr |= val;
291			}
292		}
293
294		if (ret != -EOVERFLOW) {
295			dev_err(&pdev->dev, "Failed to read u32 at index %d of child %s\n",
296					i, child->full_name);
297			continue;
298		}
299
300		if (audmux_type == IMX31_AUDMUX) {
301			if (i % 2) {
302				dev_err(&pdev->dev, "One pdcr value is missing in child node %s\n",
303						child->full_name);
304				continue;
305			}
306			imx_audmux_v2_configure_port(port, ptcr, pdcr);
307		} else {
308			imx_audmux_v1_configure_port(port, pcr);
309		}
310	}
311
312	return 0;
313}
314
315static int imx_audmux_probe(struct platform_device *pdev)
316{
317	struct resource *res;
318	const struct of_device_id *of_id =
319			of_match_device(imx_audmux_dt_ids, &pdev->dev);
320
321	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
322	audmux_base = devm_ioremap_resource(&pdev->dev, res);
323	if (IS_ERR(audmux_base))
324		return PTR_ERR(audmux_base);
325
326	audmux_clk = devm_clk_get(&pdev->dev, "audmux");
327	if (IS_ERR(audmux_clk)) {
328		dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
329				PTR_ERR(audmux_clk));
330		audmux_clk = NULL;
331	}
332
333	if (of_id)
334		pdev->id_entry = of_id->data;
335	audmux_type = pdev->id_entry->driver_data;
336	if (audmux_type == IMX31_AUDMUX)
337		audmux_debugfs_init();
338
339	if (of_id)
340		imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
341
342	return 0;
343}
344
345static int imx_audmux_remove(struct platform_device *pdev)
346{
347	if (audmux_type == IMX31_AUDMUX)
348		audmux_debugfs_remove();
349
350	return 0;
351}
352
353static struct platform_driver imx_audmux_driver = {
354	.probe		= imx_audmux_probe,
355	.remove		= imx_audmux_remove,
356	.id_table	= imx_audmux_ids,
357	.driver	= {
358		.name	= DRIVER_NAME,
359		.of_match_table = imx_audmux_dt_ids,
360	}
361};
362
363static int __init imx_audmux_init(void)
364{
365	return platform_driver_register(&imx_audmux_driver);
366}
367subsys_initcall(imx_audmux_init);
368
369static void __exit imx_audmux_exit(void)
370{
371	platform_driver_unregister(&imx_audmux_driver);
372}
373module_exit(imx_audmux_exit);
374
375MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
376MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
377MODULE_LICENSE("GPL v2");
378MODULE_ALIAS("platform:" DRIVER_NAME);
379