1 /* 2 * Atmel SSC driver 3 * 4 * Copyright (C) 2007 Atmel Corporation 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <linux/platform_device.h> 12 #include <linux/list.h> 13 #include <linux/clk.h> 14 #include <linux/err.h> 15 #include <linux/io.h> 16 #include <linux/spinlock.h> 17 #include <linux/atmel-ssc.h> 18 #include <linux/slab.h> 19 #include <linux/module.h> 20 21 #include <linux/of.h> 22 23 #include "../../sound/soc/atmel/atmel_ssc_dai.h" 24 25 /* Serialize access to ssc_list and user count */ 26 static DEFINE_SPINLOCK(user_lock); 27 static LIST_HEAD(ssc_list); 28 29 struct ssc_device *ssc_request(unsigned int ssc_num) 30 { 31 int ssc_valid = 0; 32 struct ssc_device *ssc; 33 34 spin_lock(&user_lock); 35 list_for_each_entry(ssc, &ssc_list, list) { 36 if (ssc->pdev->dev.of_node) { 37 if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc") 38 == ssc_num) { 39 ssc->pdev->id = ssc_num; 40 ssc_valid = 1; 41 break; 42 } 43 } else if (ssc->pdev->id == ssc_num) { 44 ssc_valid = 1; 45 break; 46 } 47 } 48 49 if (!ssc_valid) { 50 spin_unlock(&user_lock); 51 pr_err("ssc: ssc%d platform device is missing\n", ssc_num); 52 return ERR_PTR(-ENODEV); 53 } 54 55 if (ssc->user) { 56 spin_unlock(&user_lock); 57 dev_dbg(&ssc->pdev->dev, "module busy\n"); 58 return ERR_PTR(-EBUSY); 59 } 60 ssc->user++; 61 spin_unlock(&user_lock); 62 63 clk_prepare(ssc->clk); 64 65 return ssc; 66 } 67 EXPORT_SYMBOL(ssc_request); 68 69 void ssc_free(struct ssc_device *ssc) 70 { 71 bool disable_clk = true; 72 73 spin_lock(&user_lock); 74 if (ssc->user) 75 ssc->user--; 76 else { 77 disable_clk = false; 78 dev_dbg(&ssc->pdev->dev, "device already free\n"); 79 } 80 spin_unlock(&user_lock); 81 82 if (disable_clk) 83 clk_unprepare(ssc->clk); 84 } 85 EXPORT_SYMBOL(ssc_free); 86 87 static struct atmel_ssc_platform_data at91rm9200_config = { 88 .use_dma = 0, 89 .has_fslen_ext = 0, 90 }; 91 92 static struct atmel_ssc_platform_data at91sam9rl_config = { 93 .use_dma = 0, 94 .has_fslen_ext = 1, 95 }; 96 97 static struct atmel_ssc_platform_data at91sam9g45_config = { 98 .use_dma = 1, 99 .has_fslen_ext = 1, 100 }; 101 102 static const struct platform_device_id atmel_ssc_devtypes[] = { 103 { 104 .name = "at91rm9200_ssc", 105 .driver_data = (unsigned long) &at91rm9200_config, 106 }, { 107 .name = "at91sam9rl_ssc", 108 .driver_data = (unsigned long) &at91sam9rl_config, 109 }, { 110 .name = "at91sam9g45_ssc", 111 .driver_data = (unsigned long) &at91sam9g45_config, 112 }, { 113 /* sentinel */ 114 } 115 }; 116 117 #ifdef CONFIG_OF 118 static const struct of_device_id atmel_ssc_dt_ids[] = { 119 { 120 .compatible = "atmel,at91rm9200-ssc", 121 .data = &at91rm9200_config, 122 }, { 123 .compatible = "atmel,at91sam9rl-ssc", 124 .data = &at91sam9rl_config, 125 }, { 126 .compatible = "atmel,at91sam9g45-ssc", 127 .data = &at91sam9g45_config, 128 }, { 129 /* sentinel */ 130 } 131 }; 132 MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids); 133 #endif 134 135 static inline const struct atmel_ssc_platform_data * 136 atmel_ssc_get_driver_data(struct platform_device *pdev) 137 { 138 if (pdev->dev.of_node) { 139 const struct of_device_id *match; 140 match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node); 141 if (match == NULL) 142 return NULL; 143 return match->data; 144 } 145 146 return (struct atmel_ssc_platform_data *) 147 platform_get_device_id(pdev)->driver_data; 148 } 149 150 #ifdef CONFIG_SND_ATMEL_SOC_SSC 151 static int ssc_sound_dai_probe(struct ssc_device *ssc) 152 { 153 struct device_node *np = ssc->pdev->dev.of_node; 154 int ret; 155 int id; 156 157 ssc->sound_dai = false; 158 159 if (!of_property_read_bool(np, "#sound-dai-cells")) 160 return 0; 161 162 id = of_alias_get_id(np, "ssc"); 163 if (id < 0) 164 return id; 165 166 ret = atmel_ssc_set_audio(id); 167 ssc->sound_dai = !ret; 168 169 return ret; 170 } 171 172 static void ssc_sound_dai_remove(struct ssc_device *ssc) 173 { 174 if (!ssc->sound_dai) 175 return; 176 177 atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc")); 178 } 179 #else 180 static inline int ssc_sound_dai_probe(struct ssc_device *ssc) 181 { 182 if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells")) 183 return -ENOTSUPP; 184 185 return 0; 186 } 187 188 static inline void ssc_sound_dai_remove(struct ssc_device *ssc) 189 { 190 } 191 #endif 192 193 static int ssc_probe(struct platform_device *pdev) 194 { 195 struct resource *regs; 196 struct ssc_device *ssc; 197 const struct atmel_ssc_platform_data *plat_dat; 198 199 ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL); 200 if (!ssc) { 201 dev_dbg(&pdev->dev, "out of memory\n"); 202 return -ENOMEM; 203 } 204 205 ssc->pdev = pdev; 206 207 plat_dat = atmel_ssc_get_driver_data(pdev); 208 if (!plat_dat) 209 return -ENODEV; 210 ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat; 211 212 if (pdev->dev.of_node) { 213 struct device_node *np = pdev->dev.of_node; 214 ssc->clk_from_rk_pin = 215 of_property_read_bool(np, "atmel,clk-from-rk-pin"); 216 } 217 218 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 219 ssc->regs = devm_ioremap_resource(&pdev->dev, regs); 220 if (IS_ERR(ssc->regs)) 221 return PTR_ERR(ssc->regs); 222 223 ssc->phybase = regs->start; 224 225 ssc->clk = devm_clk_get(&pdev->dev, "pclk"); 226 if (IS_ERR(ssc->clk)) { 227 dev_dbg(&pdev->dev, "no pclk clock defined\n"); 228 return -ENXIO; 229 } 230 231 /* disable all interrupts */ 232 clk_prepare_enable(ssc->clk); 233 ssc_writel(ssc->regs, IDR, -1); 234 ssc_readl(ssc->regs, SR); 235 clk_disable_unprepare(ssc->clk); 236 237 ssc->irq = platform_get_irq(pdev, 0); 238 if (!ssc->irq) { 239 dev_dbg(&pdev->dev, "could not get irq\n"); 240 return -ENXIO; 241 } 242 243 spin_lock(&user_lock); 244 list_add_tail(&ssc->list, &ssc_list); 245 spin_unlock(&user_lock); 246 247 platform_set_drvdata(pdev, ssc); 248 249 dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n", 250 ssc->regs, ssc->irq); 251 252 if (ssc_sound_dai_probe(ssc)) 253 dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n"); 254 255 return 0; 256 } 257 258 static int ssc_remove(struct platform_device *pdev) 259 { 260 struct ssc_device *ssc = platform_get_drvdata(pdev); 261 262 ssc_sound_dai_remove(ssc); 263 264 spin_lock(&user_lock); 265 list_del(&ssc->list); 266 spin_unlock(&user_lock); 267 268 return 0; 269 } 270 271 static struct platform_driver ssc_driver = { 272 .driver = { 273 .name = "ssc", 274 .of_match_table = of_match_ptr(atmel_ssc_dt_ids), 275 }, 276 .id_table = atmel_ssc_devtypes, 277 .probe = ssc_probe, 278 .remove = ssc_remove, 279 }; 280 module_platform_driver(ssc_driver); 281 282 MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>"); 283 MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91"); 284 MODULE_LICENSE("GPL"); 285 MODULE_ALIAS("platform:ssc"); 286