fsl/imx-audmux.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright 2012 Freescale Semiconductor, Inc.
   4 // Copyright 2012 Linaro Ltd.
   5 // Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
   6 //
   7 // Initial development of this code was funded by
   8 // Phytec Messtechnik GmbH, https://www.phytec.de
   9
  10 #include <linux/clk.h>
  11 #include <linux/debugfs.h>
  12 #include <linux/err.h>
  13 #include <linux/io.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_device.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19
  20 #include "imx-audmux.h"
  21
  22 #define DRIVER_NAME "imx-audmux"
  23
  24 static struct clk *audmux_clk;
  25 static void __iomem *audmux_base;
  26 static u32 *regcache;
  27 static u32 reg_max;
  28
  29 #define IMX_AUDMUX_V2_PTCR(x)           ((x) * 8)
  30 #define IMX_AUDMUX_V2_PDCR(x)           ((x) * 8 + 4)
  31
  32 #ifdef CONFIG_DEBUG_FS
  33 static struct dentry *audmux_debugfs_root;
  34
  35 /* There is an annoying discontinuity in the SSI numbering with regard
  36  * to the Linux number of the devices */
  37 static const char *audmux_port_string(int port)
  38 {
  39         switch (port) {
  40         case MX31_AUDMUX_PORT1_SSI0:
  41                 return "imx-ssi.0";
  42         case MX31_AUDMUX_PORT2_SSI1:
  43                 return "imx-ssi.1";
  44         case MX31_AUDMUX_PORT3_SSI_PINS_3:
  45                 return "SSI3";
  46         case MX31_AUDMUX_PORT4_SSI_PINS_4:
  47                 return "SSI4";
  48         case MX31_AUDMUX_PORT5_SSI_PINS_5:
  49                 return "SSI5";
  50         case MX31_AUDMUX_PORT6_SSI_PINS_6:
  51                 return "SSI6";
  52         default:
  53                 return "UNKNOWN";
  54         }
  55 }
  56
  57 static ssize_t audmux_read_file(struct file *file, char __user *user_buf,
  58                                 size_t count, loff_t *ppos)
  59 {
  60         ssize_t ret;
  61         char *buf;
  62         uintptr_t port = (uintptr_t)file->private_data;
  63         u32 pdcr, ptcr;
  64
  65         ret = clk_prepare_enable(audmux_clk);
  66         if (ret)
  67                 return ret;
  68
  69         ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
  70         pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
  71
  72         clk_disable_unprepare(audmux_clk);
  73
  74         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
  75         if (!buf)
  76                 return -ENOMEM;
  77
  78         ret = scnprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
  79                        pdcr, ptcr);
  80
  81         if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
  82                 ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  83                                 "TxFS output from %s, ",
  84                                 audmux_port_string((ptcr >> 27) & 0x7));
  85         else
  86                 ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  87                                 "TxFS input, ");
  88
  89         if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
  90                 ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  91                                 "TxClk output from %s",
  92                                 audmux_port_string((ptcr >> 22) & 0x7));
  93         else
  94                 ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  95                                 "TxClk input");
  96
  97         ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
  98
  99         if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
 100                 ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 101                                 "Port is symmetric");
 102         } else {
 103                 if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
 104                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 105                                         "RxFS output from %s, ",
 106                                         audmux_port_string((ptcr >> 17) & 0x7));
 107                 else
 108                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 109                                         "RxFS input, ");
 110
 111                 if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
 112                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 113                                         "RxClk output from %s",
 114                                         audmux_port_string((ptcr >> 12) & 0x7));
 115                 else
 116                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 117                                         "RxClk input");
 118         }
 119
 120         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 121                         "\nData received from %s\n",
 122                         audmux_port_string((pdcr >> 13) & 0x7));
 123
 124         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
 125
 126         kfree(buf);
 127
 128         return ret;
 129 }
 130
 131 static const struct file_operations audmux_debugfs_fops = {
 132         .open = simple_open,
 133         .read = audmux_read_file,
 134         .llseek = default_llseek,
 135 };
 136
 137 static void audmux_debugfs_init(void)
 138 {
 139         uintptr_t i;
 140         char buf[20];
 141
 142         audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
 143
 144         for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
 145                 snprintf(buf, sizeof(buf), "ssi%lu", i);
 146                 debugfs_create_file(buf, 0444, audmux_debugfs_root,
 147                                     (void *)i, &audmux_debugfs_fops);
 148         }
 149 }
 150
 151 static void audmux_debugfs_remove(void)
 152 {
 153         debugfs_remove_recursive(audmux_debugfs_root);
 154 }
 155 #else
 156 static inline void audmux_debugfs_init(void)
 157 {
 158 }
 159
 160 static inline void audmux_debugfs_remove(void)
 161 {
 162 }
 163 #endif
 164
 165 static enum imx_audmux_type {
 166         IMX21_AUDMUX,
 167         IMX31_AUDMUX,
 168 } audmux_type;
 169
 170 static const struct of_device_id imx_audmux_dt_ids[] = {
 171         { .compatible = "fsl,imx21-audmux", .data = (void *)IMX21_AUDMUX, },
 172         { .compatible = "fsl,imx31-audmux", .data = (void *)IMX31_AUDMUX, },
 173         { /* sentinel */ }
 174 };
 175 MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
 176
 177 static const uint8_t port_mapping[] = {
 178         0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
 179 };
 180
 181 int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
 182 {
 183         if (audmux_type != IMX21_AUDMUX)
 184                 return -EINVAL;
 185
 186         if (!audmux_base)
 187                 return -ENOSYS;
 188
 189         if (port >= ARRAY_SIZE(port_mapping))
 190                 return -EINVAL;
 191
 192         writel(pcr, audmux_base + port_mapping[port]);
 193
 194         return 0;
 195 }
 196 EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
 197
 198 int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
 199                 unsigned int pdcr)
 200 {
 201         int ret;
 202
 203         if (audmux_type != IMX31_AUDMUX)
 204                 return -EINVAL;
 205
 206         if (!audmux_base)
 207                 return -ENOSYS;
 208
 209         ret = clk_prepare_enable(audmux_clk);
 210         if (ret)
 211                 return ret;
 212
 213         writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
 214         writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
 215
 216         clk_disable_unprepare(audmux_clk);
 217
 218         return 0;
 219 }
 220 EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
 221
 222 static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
 223                 struct device_node *of_node)
 224 {
 225         struct device_node *child;
 226
 227         for_each_available_child_of_node(of_node, child) {
 228                 unsigned int port;
 229                 unsigned int ptcr = 0;
 230                 unsigned int pdcr = 0;
 231                 unsigned int pcr = 0;
 232                 unsigned int val;
 233                 int ret;
 234                 int i = 0;
 235
 236                 ret = of_property_read_u32(child, "fsl,audmux-port", &port);
 237                 if (ret) {
 238                         dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%pOF\"\n",
 239                                         child);
 240                         continue;
 241                 }
 242                 if (!of_property_read_bool(child, "fsl,port-config")) {
 243                         dev_warn(&pdev->dev, "child node \"%pOF\" does not have property fsl,port-config\n",
 244                                         child);
 245                         continue;
 246                 }
 247
 248                 for (i = 0; (ret = of_property_read_u32_index(child,
 249                                         "fsl,port-config", i, &val)) == 0;
 250                                 ++i) {
 251                         if (audmux_type == IMX31_AUDMUX) {
 252                                 if (i % 2)
 253                                         pdcr |= val;
 254                                 else
 255                                         ptcr |= val;
 256                         } else {
 257                                 pcr |= val;
 258                         }
 259                 }
 260
 261                 if (ret != -EOVERFLOW) {
 262                         dev_err(&pdev->dev, "Failed to read u32 at index %d of child %pOF\n",
 263                                         i, child);
 264                         continue;
 265                 }
 266
 267                 if (audmux_type == IMX31_AUDMUX) {
 268                         if (i % 2) {
 269                                 dev_err(&pdev->dev, "One pdcr value is missing in child node %pOF\n",
 270                                                 child);
 271                                 continue;
 272                         }
 273                         imx_audmux_v2_configure_port(port, ptcr, pdcr);
 274                 } else {
 275                         imx_audmux_v1_configure_port(port, pcr);
 276                 }
 277         }
 278
 279         return 0;
 280 }
 281
 282 static int imx_audmux_probe(struct platform_device *pdev)
 283 {
 284         audmux_base = devm_platform_ioremap_resource(pdev, 0);
 285         if (IS_ERR(audmux_base))
 286                 return PTR_ERR(audmux_base);
 287
 288         audmux_clk = devm_clk_get(&pdev->dev, "audmux");
 289         if (IS_ERR(audmux_clk)) {
 290                 dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
 291                                 PTR_ERR(audmux_clk));
 292                 audmux_clk = NULL;
 293         }
 294
 295         audmux_type = (uintptr_t)of_device_get_match_data(&pdev->dev);
 296
 297         switch (audmux_type) {
 298         case IMX31_AUDMUX:
 299                 audmux_debugfs_init();
 300                 reg_max = 14;
 301                 break;
 302         case IMX21_AUDMUX:
 303                 reg_max = 6;
 304                 break;
 305         default:
 306                 dev_err(&pdev->dev, "unsupported version!\n");
 307                 return -EINVAL;
 308         }
 309
 310         regcache = devm_kzalloc(&pdev->dev, sizeof(u32) * reg_max, GFP_KERNEL);
 311         if (!regcache)
 312                 return -ENOMEM;
 313
 314         imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
 315
 316         return 0;
 317 }
 318
 319 static int imx_audmux_remove(struct platform_device *pdev)
 320 {
 321         if (audmux_type == IMX31_AUDMUX)
 322                 audmux_debugfs_remove();
 323
 324         return 0;
 325 }
 326
 327 #ifdef CONFIG_PM_SLEEP
 328 static int imx_audmux_suspend(struct device *dev)
 329 {
 330         int i;
 331
 332         clk_prepare_enable(audmux_clk);
 333
 334         for (i = 0; i < reg_max; i++)
 335                 regcache[i] = readl(audmux_base + i * 4);
 336
 337         clk_disable_unprepare(audmux_clk);
 338
 339         return 0;
 340 }
 341
 342 static int imx_audmux_resume(struct device *dev)
 343 {
 344         int i;
 345
 346         clk_prepare_enable(audmux_clk);
 347
 348         for (i = 0; i < reg_max; i++)
 349                 writel(regcache[i], audmux_base + i * 4);
 350
 351         clk_disable_unprepare(audmux_clk);
 352
 353         return 0;
 354 }
 355 #endif /* CONFIG_PM_SLEEP */
 356
 357 static const struct dev_pm_ops imx_audmux_pm = {
 358         SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
 359 };
 360
 361 static struct platform_driver imx_audmux_driver = {
 362         .probe          = imx_audmux_probe,
 363         .remove         = imx_audmux_remove,
 364         .driver = {
 365                 .name   = DRIVER_NAME,
 366                 .pm = &imx_audmux_pm,
 367                 .of_match_table = imx_audmux_dt_ids,
 368         }
 369 };
 370
 371 static int __init imx_audmux_init(void)
 372 {
 373         return platform_driver_register(&imx_audmux_driver);
 374 }
 375 subsys_initcall(imx_audmux_init);
 376
 377 static void __exit imx_audmux_exit(void)
 378 {
 379         platform_driver_unregister(&imx_audmux_driver);
 380 }
 381 module_exit(imx_audmux_exit);
 382
 383 MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
 384 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
 385 MODULE_LICENSE("GPL v2");
 386 MODULE_ALIAS("platform:" DRIVER_NAME);