/* * STM32 ALSA SoC Digital Audio Interface (SAI) driver. * * Copyright (C) 2016, STMicroelectronics - All Rights Reserved * Author(s): Olivier Moysan for STMicroelectronics. * * License terms: GPL V2.0. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. */ #include #include #include #include #include #include #include #include #include "stm32_sai.h" static LIST_HEAD(sync_providers); static DEFINE_MUTEX(sync_mutex); struct sync_provider { struct list_head link; struct device_node *node; int (*sync_conf)(void *data, int synco); void *data; }; static const struct stm32_sai_conf stm32_sai_conf_f4 = { .version = SAI_STM32F4, }; static const struct stm32_sai_conf stm32_sai_conf_h7 = { .version = SAI_STM32H7, }; static const struct of_device_id stm32_sai_ids[] = { { .compatible = "st,stm32f4-sai", .data = (void *)&stm32_sai_conf_f4 }, { .compatible = "st,stm32h7-sai", .data = (void *)&stm32_sai_conf_h7 }, {} }; static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci) { int ret; /* Enable peripheral clock to allow GCR register access */ ret = clk_prepare_enable(sai->pclk); if (ret) { dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret); return ret; } writel_relaxed(FIELD_PREP(SAI_GCR_SYNCIN_MASK, (synci - 1)), sai->base); clk_disable_unprepare(sai->pclk); return 0; } static int stm32_sai_sync_conf_provider(void *data, int synco) { struct stm32_sai_data *sai = (struct stm32_sai_data *)data; u32 prev_synco; int ret; /* Enable peripheral clock to allow GCR register access */ ret = clk_prepare_enable(sai->pclk); if (ret) { dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret); return ret; } dev_dbg(&sai->pdev->dev, "Set %s%s as synchro provider\n", sai->pdev->dev.of_node->name, synco == STM_SAI_SYNC_OUT_A ? "A" : "B"); prev_synco = FIELD_GET(SAI_GCR_SYNCOUT_MASK, readl_relaxed(sai->base)); if (prev_synco != STM_SAI_SYNC_OUT_NONE && synco != prev_synco) { dev_err(&sai->pdev->dev, "%s%s already set as sync provider\n", sai->pdev->dev.of_node->name, prev_synco == STM_SAI_SYNC_OUT_A ? "A" : "B"); clk_disable_unprepare(sai->pclk); return -EINVAL; } writel_relaxed(FIELD_PREP(SAI_GCR_SYNCOUT_MASK, synco), sai->base); clk_disable_unprepare(sai->pclk); return 0; } static int stm32_sai_set_sync_provider(struct device_node *np, int synco) { struct sync_provider *provider; int ret; mutex_lock(&sync_mutex); list_for_each_entry(provider, &sync_providers, link) { if (provider->node == np) { ret = provider->sync_conf(provider->data, synco); mutex_unlock(&sync_mutex); return ret; } } mutex_unlock(&sync_mutex); /* SAI sync provider not found */ return -ENODEV; } static int stm32_sai_set_sync(struct stm32_sai_data *sai, struct device_node *np_provider, int synco, int synci) { int ret; /* Configure sync client */ stm32_sai_sync_conf_client(sai, synci); /* Configure sync provider */ ret = stm32_sai_set_sync_provider(np_provider, synco); return ret; } static int stm32_sai_sync_add_provider(struct platform_device *pdev, void *data) { struct sync_provider *sp; sp = devm_kzalloc(&pdev->dev, sizeof(*sp), GFP_KERNEL); if (!sp) return -ENOMEM; sp->node = of_node_get(pdev->dev.of_node); sp->data = data; sp->sync_conf = &stm32_sai_sync_conf_provider; mutex_lock(&sync_mutex); list_add(&sp->link, &sync_providers); mutex_unlock(&sync_mutex); return 0; } static void stm32_sai_sync_del_provider(struct device_node *np) { struct sync_provider *sp; mutex_lock(&sync_mutex); list_for_each_entry(sp, &sync_providers, link) { if (sp->node == np) { list_del(&sp->link); of_node_put(sp->node); break; } } mutex_unlock(&sync_mutex); } static int stm32_sai_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct stm32_sai_data *sai; struct reset_control *rst; struct resource *res; const struct of_device_id *of_id; int ret; sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL); if (!sai) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); sai->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(sai->base)) return PTR_ERR(sai->base); of_id = of_match_device(stm32_sai_ids, &pdev->dev); if (of_id) sai->conf = (struct stm32_sai_conf *)of_id->data; else return -EINVAL; if (!STM_SAI_IS_F4(sai)) { sai->pclk = devm_clk_get(&pdev->dev, "pclk"); if (IS_ERR(sai->pclk)) { dev_err(&pdev->dev, "missing bus clock pclk\n"); return PTR_ERR(sai->pclk); } } sai->clk_x8k = devm_clk_get(&pdev->dev, "x8k"); if (IS_ERR(sai->clk_x8k)) { dev_err(&pdev->dev, "missing x8k parent clock\n"); return PTR_ERR(sai->clk_x8k); } sai->clk_x11k = devm_clk_get(&pdev->dev, "x11k"); if (IS_ERR(sai->clk_x11k)) { dev_err(&pdev->dev, "missing x11k parent clock\n"); return PTR_ERR(sai->clk_x11k); } /* init irqs */ sai->irq = platform_get_irq(pdev, 0); if (sai->irq < 0) { dev_err(&pdev->dev, "no irq for node %s\n", pdev->name); return sai->irq; } /* reset */ rst = devm_reset_control_get_exclusive(&pdev->dev, NULL); if (!IS_ERR(rst)) { reset_control_assert(rst); udelay(2); reset_control_deassert(rst); } ret = stm32_sai_sync_add_provider(pdev, sai); if (ret < 0) return ret; sai->set_sync = &stm32_sai_set_sync; sai->pdev = pdev; platform_set_drvdata(pdev, sai); ret = of_platform_populate(np, NULL, NULL, &pdev->dev); if (ret < 0) stm32_sai_sync_del_provider(np); return ret; } static int stm32_sai_remove(struct platform_device *pdev) { of_platform_depopulate(&pdev->dev); stm32_sai_sync_del_provider(pdev->dev.of_node); return 0; } MODULE_DEVICE_TABLE(of, stm32_sai_ids); static struct platform_driver stm32_sai_driver = { .driver = { .name = "st,stm32-sai", .of_match_table = stm32_sai_ids, }, .probe = stm32_sai_probe, .remove = stm32_sai_remove, }; module_platform_driver(stm32_sai_driver); MODULE_DESCRIPTION("STM32 Soc SAI Interface"); MODULE_AUTHOR("Olivier Moysan "); MODULE_ALIAS("platform:st,stm32-sai"); MODULE_LICENSE("GPL v2");