Merge tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu...
[linux-2.6-block.git] / drivers / misc / atmel-ssc.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Atmel SSC driver
4  *
5  * Copyright (C) 2007 Atmel Corporation
6  */
7
8 #include <linux/platform_device.h>
9 #include <linux/list.h>
10 #include <linux/clk.h>
11 #include <linux/err.h>
12 #include <linux/io.h>
13 #include <linux/spinlock.h>
14 #include <linux/atmel-ssc.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17
18 #include <linux/of.h>
19
20 #include "../../sound/soc/atmel/atmel_ssc_dai.h"
21
22 /* Serialize access to ssc_list and user count */
23 static DEFINE_SPINLOCK(user_lock);
24 static LIST_HEAD(ssc_list);
25
26 struct ssc_device *ssc_request(unsigned int ssc_num)
27 {
28         int ssc_valid = 0;
29         struct ssc_device *ssc;
30
31         spin_lock(&user_lock);
32         list_for_each_entry(ssc, &ssc_list, list) {
33                 if (ssc->pdev->dev.of_node) {
34                         if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")
35                                 == ssc_num) {
36                                 ssc->pdev->id = ssc_num;
37                                 ssc_valid = 1;
38                                 break;
39                         }
40                 } else if (ssc->pdev->id == ssc_num) {
41                         ssc_valid = 1;
42                         break;
43                 }
44         }
45
46         if (!ssc_valid) {
47                 spin_unlock(&user_lock);
48                 pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
49                 return ERR_PTR(-ENODEV);
50         }
51
52         if (ssc->user) {
53                 spin_unlock(&user_lock);
54                 dev_dbg(&ssc->pdev->dev, "module busy\n");
55                 return ERR_PTR(-EBUSY);
56         }
57         ssc->user++;
58         spin_unlock(&user_lock);
59
60         clk_prepare(ssc->clk);
61
62         return ssc;
63 }
64 EXPORT_SYMBOL(ssc_request);
65
66 void ssc_free(struct ssc_device *ssc)
67 {
68         bool disable_clk = true;
69
70         spin_lock(&user_lock);
71         if (ssc->user)
72                 ssc->user--;
73         else {
74                 disable_clk = false;
75                 dev_dbg(&ssc->pdev->dev, "device already free\n");
76         }
77         spin_unlock(&user_lock);
78
79         if (disable_clk)
80                 clk_unprepare(ssc->clk);
81 }
82 EXPORT_SYMBOL(ssc_free);
83
84 static struct atmel_ssc_platform_data at91rm9200_config = {
85         .use_dma = 0,
86         .has_fslen_ext = 0,
87 };
88
89 static struct atmel_ssc_platform_data at91sam9rl_config = {
90         .use_dma = 0,
91         .has_fslen_ext = 1,
92 };
93
94 static struct atmel_ssc_platform_data at91sam9g45_config = {
95         .use_dma = 1,
96         .has_fslen_ext = 1,
97 };
98
99 static const struct platform_device_id atmel_ssc_devtypes[] = {
100         {
101                 .name = "at91rm9200_ssc",
102                 .driver_data = (unsigned long) &at91rm9200_config,
103         }, {
104                 .name = "at91sam9rl_ssc",
105                 .driver_data = (unsigned long) &at91sam9rl_config,
106         }, {
107                 .name = "at91sam9g45_ssc",
108                 .driver_data = (unsigned long) &at91sam9g45_config,
109         }, {
110                 /* sentinel */
111         }
112 };
113
114 #ifdef CONFIG_OF
115 static const struct of_device_id atmel_ssc_dt_ids[] = {
116         {
117                 .compatible = "atmel,at91rm9200-ssc",
118                 .data = &at91rm9200_config,
119         }, {
120                 .compatible = "atmel,at91sam9rl-ssc",
121                 .data = &at91sam9rl_config,
122         }, {
123                 .compatible = "atmel,at91sam9g45-ssc",
124                 .data = &at91sam9g45_config,
125         }, {
126                 /* sentinel */
127         }
128 };
129 MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);
130 #endif
131
132 static inline const struct atmel_ssc_platform_data *
133         atmel_ssc_get_driver_data(struct platform_device *pdev)
134 {
135         if (pdev->dev.of_node) {
136                 const struct of_device_id *match;
137                 match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);
138                 if (match == NULL)
139                         return NULL;
140                 return match->data;
141         }
142
143         return (struct atmel_ssc_platform_data *)
144                 platform_get_device_id(pdev)->driver_data;
145 }
146
147 #ifdef CONFIG_SND_ATMEL_SOC_SSC
148 static int ssc_sound_dai_probe(struct ssc_device *ssc)
149 {
150         struct device_node *np = ssc->pdev->dev.of_node;
151         int ret;
152         int id;
153
154         ssc->sound_dai = false;
155
156         if (!of_property_read_bool(np, "#sound-dai-cells"))
157                 return 0;
158
159         id = of_alias_get_id(np, "ssc");
160         if (id < 0)
161                 return id;
162
163         ret = atmel_ssc_set_audio(id);
164         ssc->sound_dai = !ret;
165
166         return ret;
167 }
168
169 static void ssc_sound_dai_remove(struct ssc_device *ssc)
170 {
171         if (!ssc->sound_dai)
172                 return;
173
174         atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc"));
175 }
176 #else
177 static inline int ssc_sound_dai_probe(struct ssc_device *ssc)
178 {
179         if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells"))
180                 return -ENOTSUPP;
181
182         return 0;
183 }
184
185 static inline void ssc_sound_dai_remove(struct ssc_device *ssc)
186 {
187 }
188 #endif
189
190 static int ssc_probe(struct platform_device *pdev)
191 {
192         struct resource *regs;
193         struct ssc_device *ssc;
194         const struct atmel_ssc_platform_data *plat_dat;
195
196         ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);
197         if (!ssc) {
198                 dev_dbg(&pdev->dev, "out of memory\n");
199                 return -ENOMEM;
200         }
201
202         ssc->pdev = pdev;
203
204         plat_dat = atmel_ssc_get_driver_data(pdev);
205         if (!plat_dat)
206                 return -ENODEV;
207         ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
208
209         if (pdev->dev.of_node) {
210                 struct device_node *np = pdev->dev.of_node;
211                 ssc->clk_from_rk_pin =
212                         of_property_read_bool(np, "atmel,clk-from-rk-pin");
213         }
214
215         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
216         ssc->regs = devm_ioremap_resource(&pdev->dev, regs);
217         if (IS_ERR(ssc->regs))
218                 return PTR_ERR(ssc->regs);
219
220         ssc->phybase = regs->start;
221
222         ssc->clk = devm_clk_get(&pdev->dev, "pclk");
223         if (IS_ERR(ssc->clk)) {
224                 dev_dbg(&pdev->dev, "no pclk clock defined\n");
225                 return -ENXIO;
226         }
227
228         /* disable all interrupts */
229         clk_prepare_enable(ssc->clk);
230         ssc_writel(ssc->regs, IDR, -1);
231         ssc_readl(ssc->regs, SR);
232         clk_disable_unprepare(ssc->clk);
233
234         ssc->irq = platform_get_irq(pdev, 0);
235         if (!ssc->irq) {
236                 dev_dbg(&pdev->dev, "could not get irq\n");
237                 return -ENXIO;
238         }
239
240         spin_lock(&user_lock);
241         list_add_tail(&ssc->list, &ssc_list);
242         spin_unlock(&user_lock);
243
244         platform_set_drvdata(pdev, ssc);
245
246         dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
247                         ssc->regs, ssc->irq);
248
249         if (ssc_sound_dai_probe(ssc))
250                 dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n");
251
252         return 0;
253 }
254
255 static int ssc_remove(struct platform_device *pdev)
256 {
257         struct ssc_device *ssc = platform_get_drvdata(pdev);
258
259         ssc_sound_dai_remove(ssc);
260
261         spin_lock(&user_lock);
262         list_del(&ssc->list);
263         spin_unlock(&user_lock);
264
265         return 0;
266 }
267
268 static struct platform_driver ssc_driver = {
269         .driver         = {
270                 .name           = "ssc",
271                 .of_match_table = of_match_ptr(atmel_ssc_dt_ids),
272         },
273         .id_table       = atmel_ssc_devtypes,
274         .probe          = ssc_probe,
275         .remove         = ssc_remove,
276 };
277 module_platform_driver(ssc_driver);
278
279 MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
280 MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
281 MODULE_LICENSE("GPL");
282 MODULE_ALIAS("platform:ssc");