ubuntu-linux-kernel/sound/soc/stm/stm32_sai.c

275 lines
6.5 KiB
C

/*
* 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 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 <olivier.moysan@st.com>");
MODULE_ALIAS("platform:st,stm32-sai");
MODULE_LICENSE("GPL v2");