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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/* Serialize access to ssc_list and user count */
24static DEFINE_SPINLOCK(user_lock);
25static LIST_HEAD(ssc_list);
26
27struct ssc_device *ssc_request(unsigned int ssc_num)
28{
29 int ssc_valid = 0;
30 struct ssc_device *ssc;
31
32 spin_lock(&user_lock);
33 list_for_each_entry(ssc, &ssc_list, list) {
34 if (ssc->pdev->dev.of_node) {
35 if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")
36 == ssc_num) {
37 ssc->pdev->id = ssc_num;
38 ssc_valid = 1;
39 break;
40 }
41 } else if (ssc->pdev->id == ssc_num) {
42 ssc_valid = 1;
43 break;
44 }
45 }
46
47 if (!ssc_valid) {
48 spin_unlock(&user_lock);
49 pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
50 return ERR_PTR(-ENODEV);
51 }
52
53 if (ssc->user) {
54 spin_unlock(&user_lock);
55 dev_dbg(&ssc->pdev->dev, "module busy\n");
56 return ERR_PTR(-EBUSY);
57 }
58 ssc->user++;
59 spin_unlock(&user_lock);
60
61 clk_prepare(ssc->clk);
62
63 return ssc;
64}
65EXPORT_SYMBOL(ssc_request);
66
67void ssc_free(struct ssc_device *ssc)
68{
69 bool disable_clk = true;
70
71 spin_lock(&user_lock);
72 if (ssc->user)
73 ssc->user--;
74 else {
75 disable_clk = false;
76 dev_dbg(&ssc->pdev->dev, "device already free\n");
77 }
78 spin_unlock(&user_lock);
79
80 if (disable_clk)
81 clk_unprepare(ssc->clk);
82}
83EXPORT_SYMBOL(ssc_free);
84
85static struct atmel_ssc_platform_data at91rm9200_config = {
86 .use_dma = 0,
87 .has_fslen_ext = 0,
88};
89
90static struct atmel_ssc_platform_data at91sam9rl_config = {
91 .use_dma = 0,
92 .has_fslen_ext = 1,
93};
94
95static struct atmel_ssc_platform_data at91sam9g45_config = {
96 .use_dma = 1,
97 .has_fslen_ext = 1,
98};
99
100static const struct platform_device_id atmel_ssc_devtypes[] = {
101 {
102 .name = "at91rm9200_ssc",
103 .driver_data = (unsigned long) &at91rm9200_config,
104 }, {
105 .name = "at91sam9rl_ssc",
106 .driver_data = (unsigned long) &at91sam9rl_config,
107 }, {
108 .name = "at91sam9g45_ssc",
109 .driver_data = (unsigned long) &at91sam9g45_config,
110 }, {
111 /* sentinel */
112 }
113};
114
115#ifdef CONFIG_OF
116static const struct of_device_id atmel_ssc_dt_ids[] = {
117 {
118 .compatible = "atmel,at91rm9200-ssc",
119 .data = &at91rm9200_config,
120 }, {
121 .compatible = "atmel,at91sam9rl-ssc",
122 .data = &at91sam9rl_config,
123 }, {
124 .compatible = "atmel,at91sam9g45-ssc",
125 .data = &at91sam9g45_config,
126 }, {
127 /* sentinel */
128 }
129};
130MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);
131#endif
132
133static inline const struct atmel_ssc_platform_data * __init
134 atmel_ssc_get_driver_data(struct platform_device *pdev)
135{
136 if (pdev->dev.of_node) {
137 const struct of_device_id *match;
138 match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);
139 if (match == NULL)
140 return NULL;
141 return match->data;
142 }
143
144 return (struct atmel_ssc_platform_data *)
145 platform_get_device_id(pdev)->driver_data;
146}
147
148static int ssc_probe(struct platform_device *pdev)
149{
150 struct resource *regs;
151 struct ssc_device *ssc;
152 const struct atmel_ssc_platform_data *plat_dat;
153
154 ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);
155 if (!ssc) {
156 dev_dbg(&pdev->dev, "out of memory\n");
157 return -ENOMEM;
158 }
159
160 ssc->pdev = pdev;
161
162 plat_dat = atmel_ssc_get_driver_data(pdev);
163 if (!plat_dat)
164 return -ENODEV;
165 ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
166
167 if (pdev->dev.of_node) {
168 struct device_node *np = pdev->dev.of_node;
169 ssc->clk_from_rk_pin =
170 of_property_read_bool(np, "atmel,clk-from-rk-pin");
171 }
172
173 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
174 ssc->regs = devm_ioremap_resource(&pdev->dev, regs);
175 if (IS_ERR(ssc->regs))
176 return PTR_ERR(ssc->regs);
177
178 ssc->phybase = regs->start;
179
180 ssc->clk = devm_clk_get(&pdev->dev, "pclk");
181 if (IS_ERR(ssc->clk)) {
182 dev_dbg(&pdev->dev, "no pclk clock defined\n");
183 return -ENXIO;
184 }
185
186 /* disable all interrupts */
187 clk_prepare_enable(ssc->clk);
188 ssc_writel(ssc->regs, IDR, -1);
189 ssc_readl(ssc->regs, SR);
190 clk_disable_unprepare(ssc->clk);
191
192 ssc->irq = platform_get_irq(pdev, 0);
193 if (!ssc->irq) {
194 dev_dbg(&pdev->dev, "could not get irq\n");
195 return -ENXIO;
196 }
197
198 spin_lock(&user_lock);
199 list_add_tail(&ssc->list, &ssc_list);
200 spin_unlock(&user_lock);
201
202 platform_set_drvdata(pdev, ssc);
203
204 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
205 ssc->regs, ssc->irq);
206
207 return 0;
208}
209
210static int ssc_remove(struct platform_device *pdev)
211{
212 struct ssc_device *ssc = platform_get_drvdata(pdev);
213
214 spin_lock(&user_lock);
215 list_del(&ssc->list);
216 spin_unlock(&user_lock);
217
218 return 0;
219}
220
221static struct platform_driver ssc_driver = {
222 .driver = {
223 .name = "ssc",
224 .of_match_table = of_match_ptr(atmel_ssc_dt_ids),
225 },
226 .id_table = atmel_ssc_devtypes,
227 .probe = ssc_probe,
228 .remove = ssc_remove,
229};
230module_platform_driver(ssc_driver);
231
232MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
233MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
234MODULE_LICENSE("GPL");
235MODULE_ALIAS("platform:ssc");
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/* Serialize access to ssc_list and user count */
22static DEFINE_SPINLOCK(user_lock);
23static LIST_HEAD(ssc_list);
24
25struct ssc_device *ssc_request(unsigned int ssc_num)
26{
27 int ssc_valid = 0;
28 struct ssc_device *ssc;
29
30 spin_lock(&user_lock);
31 list_for_each_entry(ssc, &ssc_list, list) {
32 if (ssc->pdev->id == ssc_num) {
33 ssc_valid = 1;
34 break;
35 }
36 }
37
38 if (!ssc_valid) {
39 spin_unlock(&user_lock);
40 pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
41 return ERR_PTR(-ENODEV);
42 }
43
44 if (ssc->user) {
45 spin_unlock(&user_lock);
46 dev_dbg(&ssc->pdev->dev, "module busy\n");
47 return ERR_PTR(-EBUSY);
48 }
49 ssc->user++;
50 spin_unlock(&user_lock);
51
52 clk_enable(ssc->clk);
53
54 return ssc;
55}
56EXPORT_SYMBOL(ssc_request);
57
58void ssc_free(struct ssc_device *ssc)
59{
60 spin_lock(&user_lock);
61 if (ssc->user) {
62 ssc->user--;
63 clk_disable(ssc->clk);
64 } else {
65 dev_dbg(&ssc->pdev->dev, "device already free\n");
66 }
67 spin_unlock(&user_lock);
68}
69EXPORT_SYMBOL(ssc_free);
70
71static int __init ssc_probe(struct platform_device *pdev)
72{
73 int retval = 0;
74 struct resource *regs;
75 struct ssc_device *ssc;
76
77 ssc = kzalloc(sizeof(struct ssc_device), GFP_KERNEL);
78 if (!ssc) {
79 dev_dbg(&pdev->dev, "out of memory\n");
80 retval = -ENOMEM;
81 goto out;
82 }
83
84 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
85 if (!regs) {
86 dev_dbg(&pdev->dev, "no mmio resource defined\n");
87 retval = -ENXIO;
88 goto out_free;
89 }
90
91 ssc->clk = clk_get(&pdev->dev, "pclk");
92 if (IS_ERR(ssc->clk)) {
93 dev_dbg(&pdev->dev, "no pclk clock defined\n");
94 retval = -ENXIO;
95 goto out_free;
96 }
97
98 ssc->pdev = pdev;
99 ssc->regs = ioremap(regs->start, resource_size(regs));
100 if (!ssc->regs) {
101 dev_dbg(&pdev->dev, "ioremap failed\n");
102 retval = -EINVAL;
103 goto out_clk;
104 }
105
106 /* disable all interrupts */
107 clk_enable(ssc->clk);
108 ssc_writel(ssc->regs, IDR, ~0UL);
109 ssc_readl(ssc->regs, SR);
110 clk_disable(ssc->clk);
111
112 ssc->irq = platform_get_irq(pdev, 0);
113 if (!ssc->irq) {
114 dev_dbg(&pdev->dev, "could not get irq\n");
115 retval = -ENXIO;
116 goto out_unmap;
117 }
118
119 spin_lock(&user_lock);
120 list_add_tail(&ssc->list, &ssc_list);
121 spin_unlock(&user_lock);
122
123 platform_set_drvdata(pdev, ssc);
124
125 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
126 ssc->regs, ssc->irq);
127
128 goto out;
129
130out_unmap:
131 iounmap(ssc->regs);
132out_clk:
133 clk_put(ssc->clk);
134out_free:
135 kfree(ssc);
136out:
137 return retval;
138}
139
140static int __devexit ssc_remove(struct platform_device *pdev)
141{
142 struct ssc_device *ssc = platform_get_drvdata(pdev);
143
144 spin_lock(&user_lock);
145 iounmap(ssc->regs);
146 clk_put(ssc->clk);
147 list_del(&ssc->list);
148 kfree(ssc);
149 spin_unlock(&user_lock);
150
151 return 0;
152}
153
154static struct platform_driver ssc_driver = {
155 .remove = __devexit_p(ssc_remove),
156 .driver = {
157 .name = "ssc",
158 .owner = THIS_MODULE,
159 },
160};
161
162static int __init ssc_init(void)
163{
164 return platform_driver_probe(&ssc_driver, ssc_probe);
165}
166module_init(ssc_init);
167
168static void __exit ssc_exit(void)
169{
170 platform_driver_unregister(&ssc_driver);
171}
172module_exit(ssc_exit);
173
174MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
175MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
176MODULE_LICENSE("GPL");
177MODULE_ALIAS("platform:ssc");