1 /*
2 * STM32 ALSA SoC Digital Audio Interface (SAI) driver.
3 *
4 * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
5 * Author(s): Olivier Moysan <olivier.moysan@st.com> for STMicroelectronics.
6 *
7 * License terms: GPL V2.0.
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License version 2 as published by
11 * the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
16 * details.
17 */
18
19 #include <linux/clk.h>
20 #include <linux/delay.h>
21 #include <linux/module.h>
22 #include <linux/of_platform.h>
23 #include <linux/reset.h>
24
25 #include <sound/dmaengine_pcm.h>
26 #include <sound/core.h>
27
28 #include "stm32_sai.h"
29
30 static const struct stm32_sai_conf stm32_sai_conf_f4 = {
31 .version = SAI_STM32F4,
32 };
33
34 static const struct stm32_sai_conf stm32_sai_conf_h7 = {
35 .version = SAI_STM32H7,
36 };
37
38 static const struct of_device_id stm32_sai_ids[] = {
39 { .compatible = "st,stm32f4-sai", .data = (void *)&stm32_sai_conf_f4 },
40 { .compatible = "st,stm32h7-sai", .data = (void *)&stm32_sai_conf_h7 },
41 {}
42 };
43
stm32_sai_probe(struct platform_device * pdev)44 static int stm32_sai_probe(struct platform_device *pdev)
45 {
46 struct device_node *np = pdev->dev.of_node;
47 struct stm32_sai_data *sai;
48 struct reset_control *rst;
49 struct resource *res;
50 void __iomem *base;
51 const struct of_device_id *of_id;
52
53 sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
54 if (!sai)
55 return -ENOMEM;
56
57 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
58 base = devm_ioremap_resource(&pdev->dev, res);
59 if (IS_ERR(base))
60 return PTR_ERR(base);
61
62 of_id = of_match_device(stm32_sai_ids, &pdev->dev);
63 if (of_id)
64 sai->conf = (struct stm32_sai_conf *)of_id->data;
65 else
66 return -EINVAL;
67
68 sai->clk_x8k = devm_clk_get(&pdev->dev, "x8k");
69 if (IS_ERR(sai->clk_x8k)) {
70 dev_err(&pdev->dev, "missing x8k parent clock\n");
71 return PTR_ERR(sai->clk_x8k);
72 }
73
74 sai->clk_x11k = devm_clk_get(&pdev->dev, "x11k");
75 if (IS_ERR(sai->clk_x11k)) {
76 dev_err(&pdev->dev, "missing x11k parent clock\n");
77 return PTR_ERR(sai->clk_x11k);
78 }
79
80 /* init irqs */
81 sai->irq = platform_get_irq(pdev, 0);
82 if (sai->irq < 0) {
83 dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
84 return sai->irq;
85 }
86
87 /* reset */
88 rst = reset_control_get_exclusive(&pdev->dev, NULL);
89 if (!IS_ERR(rst)) {
90 reset_control_assert(rst);
91 udelay(2);
92 reset_control_deassert(rst);
93 }
94
95 sai->pdev = pdev;
96 platform_set_drvdata(pdev, sai);
97
98 return of_platform_populate(np, NULL, NULL, &pdev->dev);
99 }
100
stm32_sai_remove(struct platform_device * pdev)101 static int stm32_sai_remove(struct platform_device *pdev)
102 {
103 of_platform_depopulate(&pdev->dev);
104
105 return 0;
106 }
107
108 MODULE_DEVICE_TABLE(of, stm32_sai_ids);
109
110 static struct platform_driver stm32_sai_driver = {
111 .driver = {
112 .name = "st,stm32-sai",
113 .of_match_table = stm32_sai_ids,
114 },
115 .probe = stm32_sai_probe,
116 .remove = stm32_sai_remove,
117 };
118
119 module_platform_driver(stm32_sai_driver);
120
121 MODULE_DESCRIPTION("STM32 Soc SAI Interface");
122 MODULE_AUTHOR("Olivier Moysan <olivier.moysan@st.com>");
123 MODULE_ALIAS("platform:st,stm32-sai");
124 MODULE_LICENSE("GPL v2");
125