diff options
Diffstat (limited to 'drivers/misc/atmel-ssc.c')
| -rw-r--r-- | drivers/misc/atmel-ssc.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/drivers/misc/atmel-ssc.c b/drivers/misc/atmel-ssc.c new file mode 100644 index 000000000..7f9f562d6 --- /dev/null +++ b/drivers/misc/atmel-ssc.c @@ -0,0 +1,282 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Atmel SSC driver + * + * Copyright (C) 2007 Atmel Corporation + */ + +#include <linux/platform_device.h> +#include <linux/list.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/mutex.h> +#include <linux/atmel-ssc.h> +#include <linux/slab.h> +#include <linux/module.h> + +#include <linux/of.h> + +#include "../../sound/soc/atmel/atmel_ssc_dai.h" + +/* Serialize access to ssc_list and user count */ +static DEFINE_MUTEX(user_lock); +static LIST_HEAD(ssc_list); + +struct ssc_device *ssc_request(unsigned int ssc_num) +{ + int ssc_valid = 0; + struct ssc_device *ssc; + + mutex_lock(&user_lock); + list_for_each_entry(ssc, &ssc_list, list) { + if (ssc->pdev->dev.of_node) { + if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc") + == ssc_num) { + ssc->pdev->id = ssc_num; + ssc_valid = 1; + break; + } + } else if (ssc->pdev->id == ssc_num) { + ssc_valid = 1; + break; + } + } + + if (!ssc_valid) { + mutex_unlock(&user_lock); + pr_err("ssc: ssc%d platform device is missing\n", ssc_num); + return ERR_PTR(-ENODEV); + } + + if (ssc->user) { + mutex_unlock(&user_lock); + dev_dbg(&ssc->pdev->dev, "module busy\n"); + return ERR_PTR(-EBUSY); + } + ssc->user++; + mutex_unlock(&user_lock); + + clk_prepare(ssc->clk); + + return ssc; +} +EXPORT_SYMBOL(ssc_request); + +void ssc_free(struct ssc_device *ssc) +{ + bool disable_clk = true; + + mutex_lock(&user_lock); + if (ssc->user) + ssc->user--; + else { + disable_clk = false; + dev_dbg(&ssc->pdev->dev, "device already free\n"); + } + mutex_unlock(&user_lock); + + if (disable_clk) + clk_unprepare(ssc->clk); +} +EXPORT_SYMBOL(ssc_free); + +static struct atmel_ssc_platform_data at91rm9200_config = { + .use_dma = 0, + .has_fslen_ext = 0, +}; + +static struct atmel_ssc_platform_data at91sam9rl_config = { + .use_dma = 0, + .has_fslen_ext = 1, +}; + +static struct atmel_ssc_platform_data at91sam9g45_config = { + .use_dma = 1, + .has_fslen_ext = 1, +}; + +static const struct platform_device_id atmel_ssc_devtypes[] = { + { + .name = "at91rm9200_ssc", + .driver_data = (unsigned long) &at91rm9200_config, + }, { + .name = "at91sam9rl_ssc", + .driver_data = (unsigned long) &at91sam9rl_config, + }, { + .name = "at91sam9g45_ssc", + .driver_data = (unsigned long) &at91sam9g45_config, + }, { + /* sentinel */ + } +}; + +#ifdef CONFIG_OF +static const struct of_device_id atmel_ssc_dt_ids[] = { + { + .compatible = "atmel,at91rm9200-ssc", + .data = &at91rm9200_config, + }, { + .compatible = "atmel,at91sam9rl-ssc", + .data = &at91sam9rl_config, + }, { + .compatible = "atmel,at91sam9g45-ssc", + .data = &at91sam9g45_config, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids); +#endif + +static inline const struct atmel_ssc_platform_data * + atmel_ssc_get_driver_data(struct platform_device *pdev) +{ + if (pdev->dev.of_node) { + const struct of_device_id *match; + match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node); + if (match == NULL) + return NULL; + return match->data; + } + + return (struct atmel_ssc_platform_data *) + platform_get_device_id(pdev)->driver_data; +} + +#ifdef CONFIG_SND_ATMEL_SOC_SSC +static int ssc_sound_dai_probe(struct ssc_device *ssc) +{ + struct device_node *np = ssc->pdev->dev.of_node; + int ret; + int id; + + ssc->sound_dai = false; + + if (!of_property_read_bool(np, "#sound-dai-cells")) + return 0; + + id = of_alias_get_id(np, "ssc"); + if (id < 0) + return id; + + ret = atmel_ssc_set_audio(id); + ssc->sound_dai = !ret; + + return ret; +} + +static void ssc_sound_dai_remove(struct ssc_device *ssc) +{ + if (!ssc->sound_dai) + return; + + atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc")); +} +#else +static inline int ssc_sound_dai_probe(struct ssc_device *ssc) +{ + if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells")) + return -ENOTSUPP; + + return 0; +} + +static inline void ssc_sound_dai_remove(struct ssc_device *ssc) +{ +} +#endif + +static int ssc_probe(struct platform_device *pdev) +{ + struct resource *regs; + struct ssc_device *ssc; + const struct atmel_ssc_platform_data *plat_dat; + + ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL); + if (!ssc) { + dev_dbg(&pdev->dev, "out of memory\n"); + return -ENOMEM; + } + + ssc->pdev = pdev; + + plat_dat = atmel_ssc_get_driver_data(pdev); + if (!plat_dat) + return -ENODEV; + ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat; + + if (pdev->dev.of_node) { + struct device_node *np = pdev->dev.of_node; + ssc->clk_from_rk_pin = + of_property_read_bool(np, "atmel,clk-from-rk-pin"); + } + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ssc->regs = devm_ioremap_resource(&pdev->dev, regs); + if (IS_ERR(ssc->regs)) + return PTR_ERR(ssc->regs); + + ssc->phybase = regs->start; + + ssc->clk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(ssc->clk)) { + dev_dbg(&pdev->dev, "no pclk clock defined\n"); + return -ENXIO; + } + + /* disable all interrupts */ + clk_prepare_enable(ssc->clk); + ssc_writel(ssc->regs, IDR, -1); + ssc_readl(ssc->regs, SR); + clk_disable_unprepare(ssc->clk); + + ssc->irq = platform_get_irq(pdev, 0); + if (ssc->irq < 0) { + dev_dbg(&pdev->dev, "could not get irq\n"); + return ssc->irq; + } + + mutex_lock(&user_lock); + list_add_tail(&ssc->list, &ssc_list); + mutex_unlock(&user_lock); + + platform_set_drvdata(pdev, ssc); + + dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n", + ssc->regs, ssc->irq); + + if (ssc_sound_dai_probe(ssc)) + dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n"); + + return 0; +} + +static int ssc_remove(struct platform_device *pdev) +{ + struct ssc_device *ssc = platform_get_drvdata(pdev); + + ssc_sound_dai_remove(ssc); + + mutex_lock(&user_lock); + list_del(&ssc->list); + mutex_unlock(&user_lock); + + return 0; +} + +static struct platform_driver ssc_driver = { + .driver = { + .name = "ssc", + .of_match_table = of_match_ptr(atmel_ssc_dt_ids), + }, + .id_table = atmel_ssc_devtypes, + .probe = ssc_probe, + .remove = ssc_remove, +}; +module_platform_driver(ssc_driver); + +MODULE_AUTHOR("Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>"); +MODULE_DESCRIPTION("SSC driver for Atmel AT91"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ssc"); |