| /* |
| * STM32 ALSA SoC Digital Audio Interface (SAI) driver. |
| * |
| * Copyright (C) 2016, STMicroelectronics - All Rights Reserved |
| * Author(s): Olivier Moysan <olivier.moysan@st.com> 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 <linux/bitfield.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/module.h> |
| #include <linux/of_platform.h> |
| #include <linux/reset.h> |
| |
| #include <sound/dmaengine_pcm.h> |
| #include <sound/core.h> |
| |
| #include "stm32_sai.h" |
| |
| static const struct stm32_sai_conf stm32_sai_conf_f4 = { |
| .version = SAI_STM32F4, |
| .has_spdif = false, |
| }; |
| |
| static const struct stm32_sai_conf stm32_sai_conf_h7 = { |
| .version = SAI_STM32H7, |
| .has_spdif = true, |
| }; |
| |
| 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(struct stm32_sai_data *sai, int synco) |
| { |
| 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 %pOFn%s as synchro provider\n", |
| sai->pdev->dev.of_node, |
| 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, "%pOFn%s already set as sync provider\n", |
| sai->pdev->dev.of_node, |
| 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(struct stm32_sai_data *sai_client, |
| struct device_node *np_provider, |
| int synco, int synci) |
| { |
| struct platform_device *pdev = of_find_device_by_node(np_provider); |
| struct stm32_sai_data *sai_provider; |
| int ret; |
| |
| if (!pdev) { |
| dev_err(&sai_client->pdev->dev, |
| "Device not found for node %pOFn\n", np_provider); |
| return -ENODEV; |
| } |
| |
| sai_provider = platform_get_drvdata(pdev); |
| if (!sai_provider) { |
| dev_err(&sai_client->pdev->dev, |
| "SAI sync provider data not found\n"); |
| return -EINVAL; |
| } |
| |
| /* Configure sync client */ |
| ret = stm32_sai_sync_conf_client(sai_client, synci); |
| if (ret < 0) |
| return ret; |
| |
| /* Configure sync provider */ |
| return stm32_sai_sync_conf_provider(sai_provider, synco); |
| } |
| |
| static int stm32_sai_probe(struct platform_device *pdev) |
| { |
| struct stm32_sai_data *sai; |
| struct reset_control *rst; |
| struct resource *res; |
| const struct of_device_id *of_id; |
| |
| 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); |
| } |
| |
| sai->pdev = pdev; |
| sai->set_sync = &stm32_sai_set_sync; |
| platform_set_drvdata(pdev, sai); |
| |
| return devm_of_platform_populate(&pdev->dev); |
| } |
| |
| 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, |
| }; |
| |
| module_platform_driver(stm32_sai_driver); |
| |
| MODULE_DESCRIPTION("STM32 Soc SAI Interface"); |
| MODULE_AUTHOR("Olivier Moysan <olivier.moysan@st.com>"); |
| MODULE_ALIAS("platform:st,stm32-sai"); |
| MODULE_LICENSE("GPL v2"); |