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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Atmel SSC driver4 *5 * Copyright (C) 2007 Atmel Corporation6 */7 8#include <linux/platform_device.h>9#include <linux/list.h>10#include <linux/clk.h>11#include <linux/err.h>12#include <linux/io.h>13#include <linux/mutex.h>14#include <linux/atmel-ssc.h>15#include <linux/slab.h>16#include <linux/module.h>17 18#include <linux/of.h>19 20#include "../../sound/soc/atmel/atmel_ssc_dai.h"21 22/* Serialize access to ssc_list and user count */23static DEFINE_MUTEX(user_lock);24static LIST_HEAD(ssc_list);25 26struct ssc_device *ssc_request(unsigned int ssc_num)27{28 int ssc_valid = 0;29 struct ssc_device *ssc;30 31 mutex_lock(&user_lock);32 list_for_each_entry(ssc, &ssc_list, list) {33 if (ssc->pdev->dev.of_node) {34 if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")35 == ssc_num) {36 ssc->pdev->id = ssc_num;37 ssc_valid = 1;38 break;39 }40 } else if (ssc->pdev->id == ssc_num) {41 ssc_valid = 1;42 break;43 }44 }45 46 if (!ssc_valid) {47 mutex_unlock(&user_lock);48 pr_err("ssc: ssc%d platform device is missing\n", ssc_num);49 return ERR_PTR(-ENODEV);50 }51 52 if (ssc->user) {53 mutex_unlock(&user_lock);54 dev_dbg(&ssc->pdev->dev, "module busy\n");55 return ERR_PTR(-EBUSY);56 }57 ssc->user++;58 mutex_unlock(&user_lock);59 60 clk_prepare(ssc->clk);61 62 return ssc;63}64EXPORT_SYMBOL(ssc_request);65 66void ssc_free(struct ssc_device *ssc)67{68 bool disable_clk = true;69 70 mutex_lock(&user_lock);71 if (ssc->user)72 ssc->user--;73 else {74 disable_clk = false;75 dev_dbg(&ssc->pdev->dev, "device already free\n");76 }77 mutex_unlock(&user_lock);78 79 if (disable_clk)80 clk_unprepare(ssc->clk);81}82EXPORT_SYMBOL(ssc_free);83 84static struct atmel_ssc_platform_data at91rm9200_config = {85 .use_dma = 0,86 .has_fslen_ext = 0,87};88 89static struct atmel_ssc_platform_data at91sam9rl_config = {90 .use_dma = 0,91 .has_fslen_ext = 1,92};93 94static struct atmel_ssc_platform_data at91sam9g45_config = {95 .use_dma = 1,96 .has_fslen_ext = 1,97};98 99static const struct platform_device_id atmel_ssc_devtypes[] = {100 {101 .name = "at91rm9200_ssc",102 .driver_data = (unsigned long) &at91rm9200_config,103 }, {104 .name = "at91sam9rl_ssc",105 .driver_data = (unsigned long) &at91sam9rl_config,106 }, {107 .name = "at91sam9g45_ssc",108 .driver_data = (unsigned long) &at91sam9g45_config,109 }, {110 /* sentinel */111 }112};113 114#ifdef CONFIG_OF115static const struct of_device_id atmel_ssc_dt_ids[] = {116 {117 .compatible = "atmel,at91rm9200-ssc",118 .data = &at91rm9200_config,119 }, {120 .compatible = "atmel,at91sam9rl-ssc",121 .data = &at91sam9rl_config,122 }, {123 .compatible = "atmel,at91sam9g45-ssc",124 .data = &at91sam9g45_config,125 }, {126 /* sentinel */127 }128};129MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);130#endif131 132static inline const struct atmel_ssc_platform_data *133 atmel_ssc_get_driver_data(struct platform_device *pdev)134{135 if (pdev->dev.of_node) {136 const struct of_device_id *match;137 match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);138 if (match == NULL)139 return NULL;140 return match->data;141 }142 143 return (struct atmel_ssc_platform_data *)144 platform_get_device_id(pdev)->driver_data;145}146 147#ifdef CONFIG_SND_ATMEL_SOC_SSC148static int ssc_sound_dai_probe(struct ssc_device *ssc)149{150 struct device_node *np = ssc->pdev->dev.of_node;151 int ret;152 int id;153 154 ssc->sound_dai = false;155 156 if (!of_property_read_bool(np, "#sound-dai-cells"))157 return 0;158 159 id = of_alias_get_id(np, "ssc");160 if (id < 0)161 return id;162 163 ret = atmel_ssc_set_audio(id);164 ssc->sound_dai = !ret;165 166 return ret;167}168 169static void ssc_sound_dai_remove(struct ssc_device *ssc)170{171 if (!ssc->sound_dai)172 return;173 174 atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc"));175}176#else177static inline int ssc_sound_dai_probe(struct ssc_device *ssc)178{179 if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells"))180 return -ENOTSUPP;181 182 return 0;183}184 185static inline void ssc_sound_dai_remove(struct ssc_device *ssc)186{187}188#endif189 190static int ssc_probe(struct platform_device *pdev)191{192 struct resource *regs;193 struct ssc_device *ssc;194 const struct atmel_ssc_platform_data *plat_dat;195 196 ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);197 if (!ssc) {198 dev_dbg(&pdev->dev, "out of memory\n");199 return -ENOMEM;200 }201 202 ssc->pdev = pdev;203 204 plat_dat = atmel_ssc_get_driver_data(pdev);205 if (!plat_dat)206 return -ENODEV;207 ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;208 209 if (pdev->dev.of_node) {210 struct device_node *np = pdev->dev.of_node;211 ssc->clk_from_rk_pin =212 of_property_read_bool(np, "atmel,clk-from-rk-pin");213 }214 215 ssc->regs = devm_platform_get_and_ioremap_resource(pdev, 0, ®s);216 if (IS_ERR(ssc->regs))217 return PTR_ERR(ssc->regs);218 219 ssc->phybase = regs->start;220 221 ssc->clk = devm_clk_get(&pdev->dev, "pclk");222 if (IS_ERR(ssc->clk)) {223 dev_dbg(&pdev->dev, "no pclk clock defined\n");224 return -ENXIO;225 }226 227 /* disable all interrupts */228 clk_prepare_enable(ssc->clk);229 ssc_writel(ssc->regs, IDR, -1);230 ssc_readl(ssc->regs, SR);231 clk_disable_unprepare(ssc->clk);232 233 ssc->irq = platform_get_irq(pdev, 0);234 if (ssc->irq < 0) {235 dev_dbg(&pdev->dev, "could not get irq\n");236 return ssc->irq;237 }238 239 mutex_lock(&user_lock);240 list_add_tail(&ssc->list, &ssc_list);241 mutex_unlock(&user_lock);242 243 platform_set_drvdata(pdev, ssc);244 245 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",246 ssc->regs, ssc->irq);247 248 if (ssc_sound_dai_probe(ssc))249 dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n");250 251 return 0;252}253 254static void ssc_remove(struct platform_device *pdev)255{256 struct ssc_device *ssc = platform_get_drvdata(pdev);257 258 ssc_sound_dai_remove(ssc);259 260 mutex_lock(&user_lock);261 list_del(&ssc->list);262 mutex_unlock(&user_lock);263}264 265static struct platform_driver ssc_driver = {266 .driver = {267 .name = "ssc",268 .of_match_table = of_match_ptr(atmel_ssc_dt_ids),269 },270 .id_table = atmel_ssc_devtypes,271 .probe = ssc_probe,272 .remove_new = ssc_remove,273};274module_platform_driver(ssc_driver);275 276MODULE_AUTHOR("Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>");277MODULE_DESCRIPTION("SSC driver for Atmel AT91");278MODULE_LICENSE("GPL");279MODULE_ALIAS("platform:ssc");280