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 of_device_id stm32_sai_ids[] = { 31 { .compatible = "st,stm32f4-sai", .data = (void *)SAI_STM32F4 }, 32 {} 33 }; 34 35 static int stm32_sai_probe(struct platform_device *pdev) 36 { 37 struct device_node *np = pdev->dev.of_node; 38 struct stm32_sai_data *sai; 39 struct reset_control *rst; 40 struct resource *res; 41 void __iomem *base; 42 const struct of_device_id *of_id; 43 44 sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL); 45 if (!sai) 46 return -ENOMEM; 47 48 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 49 base = devm_ioremap_resource(&pdev->dev, res); 50 if (IS_ERR(base)) 51 return PTR_ERR(base); 52 53 of_id = of_match_device(stm32_sai_ids, &pdev->dev); 54 if (of_id) 55 sai->version = (enum stm32_sai_version)of_id->data; 56 else 57 return -EINVAL; 58 59 sai->clk_x8k = devm_clk_get(&pdev->dev, "x8k"); 60 if (IS_ERR(sai->clk_x8k)) { 61 dev_err(&pdev->dev, "missing x8k parent clock\n"); 62 return PTR_ERR(sai->clk_x8k); 63 } 64 65 sai->clk_x11k = devm_clk_get(&pdev->dev, "x11k"); 66 if (IS_ERR(sai->clk_x11k)) { 67 dev_err(&pdev->dev, "missing x11k parent clock\n"); 68 return PTR_ERR(sai->clk_x11k); 69 } 70 71 /* init irqs */ 72 sai->irq = platform_get_irq(pdev, 0); 73 if (sai->irq < 0) { 74 dev_err(&pdev->dev, "no irq for node %s\n", pdev->name); 75 return sai->irq; 76 } 77 78 /* reset */ 79 rst = reset_control_get(&pdev->dev, NULL); 80 if (!IS_ERR(rst)) { 81 reset_control_assert(rst); 82 udelay(2); 83 reset_control_deassert(rst); 84 } 85 86 sai->pdev = pdev; 87 platform_set_drvdata(pdev, sai); 88 89 return of_platform_populate(np, NULL, NULL, &pdev->dev); 90 } 91 92 static int stm32_sai_remove(struct platform_device *pdev) 93 { 94 of_platform_depopulate(&pdev->dev); 95 96 return 0; 97 } 98 99 MODULE_DEVICE_TABLE(of, stm32_sai_ids); 100 101 static struct platform_driver stm32_sai_driver = { 102 .driver = { 103 .name = "st,stm32-sai", 104 .of_match_table = stm32_sai_ids, 105 }, 106 .probe = stm32_sai_probe, 107 .remove = stm32_sai_remove, 108 }; 109 110 module_platform_driver(stm32_sai_driver); 111 112 MODULE_DESCRIPTION("STM32 Soc SAI Interface"); 113 MODULE_AUTHOR("Olivier Moysan <olivier.moysan@st.com>"); 114 MODULE_ALIAS("platform:st,stm32-sai"); 115 MODULE_LICENSE("GPL v2"); 116