diff options
Diffstat (limited to '')
| -rw-r--r-- | sound/soc/stm/stm32_sai.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/sound/soc/stm/stm32_sai.c b/sound/soc/stm/stm32_sai.c new file mode 100644 index 000000000..540c4a004 --- /dev/null +++ b/sound/soc/stm/stm32_sai.c @@ -0,0 +1,211 @@ +/* + * 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 %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(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 %s\n", np_provider->name); + return -ENODEV; + } + + sai_provider = platform_get_drvdata(pdev); + if (!sai_provider) { + dev_err(&sai_client->pdev->dev, + "SAI sync provider data not found\n"); + ret = -EINVAL; + goto out_put_dev; + } + + /* Configure sync client */ + ret = stm32_sai_sync_conf_client(sai_client, synci); + if (ret < 0) + goto out_put_dev; + + /* Configure sync provider */ + ret = stm32_sai_sync_conf_provider(sai_provider, synco); + +out_put_dev: + put_device(&pdev->dev); + return ret; +} + +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"); |