1 /*
2 * Atmel SSC driver
3 *
4 * Copyright (C) 2007 Atmel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #include <linux/platform_device.h>
12 #include <linux/list.h>
13 #include <linux/clk.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/spinlock.h>
17 #include <linux/atmel-ssc.h>
18 #include <linux/slab.h>
19 #include <linux/module.h>
20
21 #include <linux/of.h>
22
23 #include "../../sound/soc/atmel/atmel_ssc_dai.h"
24
25 /* Serialize access to ssc_list and user count */
26 static DEFINE_SPINLOCK(user_lock);
27 static LIST_HEAD(ssc_list);
28
ssc_request(unsigned int ssc_num)29 struct ssc_device *ssc_request(unsigned int ssc_num)
30 {
31 int ssc_valid = 0;
32 struct ssc_device *ssc;
33
34 spin_lock(&user_lock);
35 list_for_each_entry(ssc, &ssc_list, list) {
36 if (ssc->pdev->dev.of_node) {
37 if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")
38 == ssc_num) {
39 ssc->pdev->id = ssc_num;
40 ssc_valid = 1;
41 break;
42 }
43 } else if (ssc->pdev->id == ssc_num) {
44 ssc_valid = 1;
45 break;
46 }
47 }
48
49 if (!ssc_valid) {
50 spin_unlock(&user_lock);
51 pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
52 return ERR_PTR(-ENODEV);
53 }
54
55 if (ssc->user) {
56 spin_unlock(&user_lock);
57 dev_dbg(&ssc->pdev->dev, "module busy\n");
58 return ERR_PTR(-EBUSY);
59 }
60 ssc->user++;
61 spin_unlock(&user_lock);
62
63 clk_prepare(ssc->clk);
64
65 return ssc;
66 }
67 EXPORT_SYMBOL(ssc_request);
68
ssc_free(struct ssc_device * ssc)69 void ssc_free(struct ssc_device *ssc)
70 {
71 bool disable_clk = true;
72
73 spin_lock(&user_lock);
74 if (ssc->user)
75 ssc->user--;
76 else {
77 disable_clk = false;
78 dev_dbg(&ssc->pdev->dev, "device already free\n");
79 }
80 spin_unlock(&user_lock);
81
82 if (disable_clk)
83 clk_unprepare(ssc->clk);
84 }
85 EXPORT_SYMBOL(ssc_free);
86
87 static struct atmel_ssc_platform_data at91rm9200_config = {
88 .use_dma = 0,
89 .has_fslen_ext = 0,
90 };
91
92 static struct atmel_ssc_platform_data at91sam9rl_config = {
93 .use_dma = 0,
94 .has_fslen_ext = 1,
95 };
96
97 static struct atmel_ssc_platform_data at91sam9g45_config = {
98 .use_dma = 1,
99 .has_fslen_ext = 1,
100 };
101
102 static const struct platform_device_id atmel_ssc_devtypes[] = {
103 {
104 .name = "at91rm9200_ssc",
105 .driver_data = (unsigned long) &at91rm9200_config,
106 }, {
107 .name = "at91sam9rl_ssc",
108 .driver_data = (unsigned long) &at91sam9rl_config,
109 }, {
110 .name = "at91sam9g45_ssc",
111 .driver_data = (unsigned long) &at91sam9g45_config,
112 }, {
113 /* sentinel */
114 }
115 };
116
117 #ifdef CONFIG_OF
118 static const struct of_device_id atmel_ssc_dt_ids[] = {
119 {
120 .compatible = "atmel,at91rm9200-ssc",
121 .data = &at91rm9200_config,
122 }, {
123 .compatible = "atmel,at91sam9rl-ssc",
124 .data = &at91sam9rl_config,
125 }, {
126 .compatible = "atmel,at91sam9g45-ssc",
127 .data = &at91sam9g45_config,
128 }, {
129 /* sentinel */
130 }
131 };
132 MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);
133 #endif
134
135 static inline const struct atmel_ssc_platform_data * __init
atmel_ssc_get_driver_data(struct platform_device * pdev)136 atmel_ssc_get_driver_data(struct platform_device *pdev)
137 {
138 if (pdev->dev.of_node) {
139 const struct of_device_id *match;
140 match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);
141 if (match == NULL)
142 return NULL;
143 return match->data;
144 }
145
146 return (struct atmel_ssc_platform_data *)
147 platform_get_device_id(pdev)->driver_data;
148 }
149
150 #ifdef CONFIG_SND_ATMEL_SOC_SSC
ssc_sound_dai_probe(struct ssc_device * ssc)151 static int ssc_sound_dai_probe(struct ssc_device *ssc)
152 {
153 struct device_node *np = ssc->pdev->dev.of_node;
154 int ret;
155 int id;
156
157 ssc->sound_dai = false;
158
159 if (!of_property_read_bool(np, "#sound-dai-cells"))
160 return 0;
161
162 id = of_alias_get_id(np, "ssc");
163 if (id < 0)
164 return id;
165
166 ret = atmel_ssc_set_audio(id);
167 ssc->sound_dai = !ret;
168
169 return ret;
170 }
171
ssc_sound_dai_remove(struct ssc_device * ssc)172 static void ssc_sound_dai_remove(struct ssc_device *ssc)
173 {
174 if (!ssc->sound_dai)
175 return;
176
177 atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc"));
178 }
179 #else
ssc_sound_dai_probe(struct ssc_device * ssc)180 static inline int ssc_sound_dai_probe(struct ssc_device *ssc)
181 {
182 if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells"))
183 return -ENOTSUPP;
184
185 return 0;
186 }
187
ssc_sound_dai_remove(struct ssc_device * ssc)188 static inline void ssc_sound_dai_remove(struct ssc_device *ssc)
189 {
190 }
191 #endif
192
ssc_probe(struct platform_device * pdev)193 static int ssc_probe(struct platform_device *pdev)
194 {
195 struct resource *regs;
196 struct ssc_device *ssc;
197 const struct atmel_ssc_platform_data *plat_dat;
198
199 ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);
200 if (!ssc) {
201 dev_dbg(&pdev->dev, "out of memory\n");
202 return -ENOMEM;
203 }
204
205 ssc->pdev = pdev;
206
207 plat_dat = atmel_ssc_get_driver_data(pdev);
208 if (!plat_dat)
209 return -ENODEV;
210 ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
211
212 if (pdev->dev.of_node) {
213 struct device_node *np = pdev->dev.of_node;
214 ssc->clk_from_rk_pin =
215 of_property_read_bool(np, "atmel,clk-from-rk-pin");
216 }
217
218 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
219 ssc->regs = devm_ioremap_resource(&pdev->dev, regs);
220 if (IS_ERR(ssc->regs))
221 return PTR_ERR(ssc->regs);
222
223 ssc->phybase = regs->start;
224
225 ssc->clk = devm_clk_get(&pdev->dev, "pclk");
226 if (IS_ERR(ssc->clk)) {
227 dev_dbg(&pdev->dev, "no pclk clock defined\n");
228 return -ENXIO;
229 }
230
231 /* disable all interrupts */
232 clk_prepare_enable(ssc->clk);
233 ssc_writel(ssc->regs, IDR, -1);
234 ssc_readl(ssc->regs, SR);
235 clk_disable_unprepare(ssc->clk);
236
237 ssc->irq = platform_get_irq(pdev, 0);
238 if (!ssc->irq) {
239 dev_dbg(&pdev->dev, "could not get irq\n");
240 return -ENXIO;
241 }
242
243 spin_lock(&user_lock);
244 list_add_tail(&ssc->list, &ssc_list);
245 spin_unlock(&user_lock);
246
247 platform_set_drvdata(pdev, ssc);
248
249 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
250 ssc->regs, ssc->irq);
251
252 if (ssc_sound_dai_probe(ssc))
253 dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n");
254
255 return 0;
256 }
257
ssc_remove(struct platform_device * pdev)258 static int ssc_remove(struct platform_device *pdev)
259 {
260 struct ssc_device *ssc = platform_get_drvdata(pdev);
261
262 ssc_sound_dai_remove(ssc);
263
264 spin_lock(&user_lock);
265 list_del(&ssc->list);
266 spin_unlock(&user_lock);
267
268 return 0;
269 }
270
271 static struct platform_driver ssc_driver = {
272 .driver = {
273 .name = "ssc",
274 .of_match_table = of_match_ptr(atmel_ssc_dt_ids),
275 },
276 .id_table = atmel_ssc_devtypes,
277 .probe = ssc_probe,
278 .remove = ssc_remove,
279 };
280 module_platform_driver(ssc_driver);
281
282 MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
283 MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
284 MODULE_LICENSE("GPL");
285 MODULE_ALIAS("platform:ssc");
286
