1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Atmel SSC driver 4 * 5 * Copyright (C) 2007 Atmel Corporation 6 */ 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 */ 23 static DEFINE_MUTEX(user_lock); 24 static LIST_HEAD(ssc_list); 25 26 struct 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 } 64 EXPORT_SYMBOL(ssc_request); 65 66 void 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 } 82 EXPORT_SYMBOL(ssc_free); 83 84 static struct atmel_ssc_platform_data at91rm9200_config = { 85 .use_dma = 0, 86 .has_fslen_ext = 0, 87 }; 88 89 static struct atmel_ssc_platform_data at91sam9rl_config = { 90 .use_dma = 0, 91 .has_fslen_ext = 1, 92 }; 93 94 static struct atmel_ssc_platform_data at91sam9g45_config = { 95 .use_dma = 1, 96 .has_fslen_ext = 1, 97 }; 98 99 static 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_OF 115 static 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 }; 129 MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids); 130 #endif 131 132 static 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_SSC 148 static 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 } 168 169 static 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 #else 177 static 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 } 184 185 static inline void ssc_sound_dai_remove(struct ssc_device *ssc) 186 { 187 } 188 #endif 189 190 static 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 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 216 ssc->regs = devm_ioremap_resource(&pdev->dev, regs); 217 if (IS_ERR(ssc->regs)) 218 return PTR_ERR(ssc->regs); 219 220 ssc->phybase = regs->start; 221 222 ssc->clk = devm_clk_get(&pdev->dev, "pclk"); 223 if (IS_ERR(ssc->clk)) { 224 dev_dbg(&pdev->dev, "no pclk clock defined\n"); 225 return -ENXIO; 226 } 227 228 /* disable all interrupts */ 229 clk_prepare_enable(ssc->clk); 230 ssc_writel(ssc->regs, IDR, -1); 231 ssc_readl(ssc->regs, SR); 232 clk_disable_unprepare(ssc->clk); 233 234 ssc->irq = platform_get_irq(pdev, 0); 235 if (ssc->irq < 0) { 236 dev_dbg(&pdev->dev, "could not get irq\n"); 237 return ssc->irq; 238 } 239 240 mutex_lock(&user_lock); 241 list_add_tail(&ssc->list, &ssc_list); 242 mutex_unlock(&user_lock); 243 244 platform_set_drvdata(pdev, ssc); 245 246 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n", 247 ssc->regs, ssc->irq); 248 249 if (ssc_sound_dai_probe(ssc)) 250 dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n"); 251 252 return 0; 253 } 254 255 static int ssc_remove(struct platform_device *pdev) 256 { 257 struct ssc_device *ssc = platform_get_drvdata(pdev); 258 259 ssc_sound_dai_remove(ssc); 260 261 mutex_lock(&user_lock); 262 list_del(&ssc->list); 263 mutex_unlock(&user_lock); 264 265 return 0; 266 } 267 268 static struct platform_driver ssc_driver = { 269 .driver = { 270 .name = "ssc", 271 .of_match_table = of_match_ptr(atmel_ssc_dt_ids), 272 }, 273 .id_table = atmel_ssc_devtypes, 274 .probe = ssc_probe, 275 .remove = ssc_remove, 276 }; 277 module_platform_driver(ssc_driver); 278 279 MODULE_AUTHOR("Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>"); 280 MODULE_DESCRIPTION("SSC driver for Atmel AT91"); 281 MODULE_LICENSE("GPL"); 282 MODULE_ALIAS("platform:ssc"); 283