linux/sound/soc/fsl/imx-audmux.c
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   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
  24static struct clk *audmux_clk;
  25static void __iomem *audmux_base;
  26static u32 *regcache;
  27static 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
  33static 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 */
  37static 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
  57static 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        if (audmux_clk) {
  66                ret = clk_prepare_enable(audmux_clk);
  67                if (ret)
  68                        return ret;
  69        }
  70
  71        ptcr = readl(audmux_base + IMX_AUDMUX_V2_PTCR(port));
  72        pdcr = readl(audmux_base + IMX_AUDMUX_V2_PDCR(port));
  73
  74        if (audmux_clk)
  75                clk_disable_unprepare(audmux_clk);
  76
  77        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
  78        if (!buf)
  79                return -ENOMEM;
  80
  81        ret = scnprintf(buf, PAGE_SIZE, "PDCR: %08x\nPTCR: %08x\n",
  82                       pdcr, ptcr);
  83
  84        if (ptcr & IMX_AUDMUX_V2_PTCR_TFSDIR)
  85                ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  86                                "TxFS output from %s, ",
  87                                audmux_port_string((ptcr >> 27) & 0x7));
  88        else
  89                ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  90                                "TxFS input, ");
  91
  92        if (ptcr & IMX_AUDMUX_V2_PTCR_TCLKDIR)
  93                ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  94                                "TxClk output from %s",
  95                                audmux_port_string((ptcr >> 22) & 0x7));
  96        else
  97                ret += scnprintf(buf + ret, PAGE_SIZE - ret,
  98                                "TxClk input");
  99
 100        ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 101
 102        if (ptcr & IMX_AUDMUX_V2_PTCR_SYN) {
 103                ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 104                                "Port is symmetric");
 105        } else {
 106                if (ptcr & IMX_AUDMUX_V2_PTCR_RFSDIR)
 107                        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 108                                        "RxFS output from %s, ",
 109                                        audmux_port_string((ptcr >> 17) & 0x7));
 110                else
 111                        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 112                                        "RxFS input, ");
 113
 114                if (ptcr & IMX_AUDMUX_V2_PTCR_RCLKDIR)
 115                        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 116                                        "RxClk output from %s",
 117                                        audmux_port_string((ptcr >> 12) & 0x7));
 118                else
 119                        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 120                                        "RxClk input");
 121        }
 122
 123        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 124                        "\nData received from %s\n",
 125                        audmux_port_string((pdcr >> 13) & 0x7));
 126
 127        ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
 128
 129        kfree(buf);
 130
 131        return ret;
 132}
 133
 134static const struct file_operations audmux_debugfs_fops = {
 135        .open = simple_open,
 136        .read = audmux_read_file,
 137        .llseek = default_llseek,
 138};
 139
 140static void audmux_debugfs_init(void)
 141{
 142        uintptr_t i;
 143        char buf[20];
 144
 145        audmux_debugfs_root = debugfs_create_dir("audmux", NULL);
 146
 147        for (i = 0; i < MX31_AUDMUX_PORT7_SSI_PINS_7 + 1; i++) {
 148                snprintf(buf, sizeof(buf), "ssi%lu", i);
 149                debugfs_create_file(buf, 0444, audmux_debugfs_root,
 150                                    (void *)i, &audmux_debugfs_fops);
 151        }
 152}
 153
 154static void audmux_debugfs_remove(void)
 155{
 156        debugfs_remove_recursive(audmux_debugfs_root);
 157}
 158#else
 159static inline void audmux_debugfs_init(void)
 160{
 161}
 162
 163static inline void audmux_debugfs_remove(void)
 164{
 165}
 166#endif
 167
 168static enum imx_audmux_type {
 169        IMX21_AUDMUX,
 170        IMX31_AUDMUX,
 171} audmux_type;
 172
 173static const struct of_device_id imx_audmux_dt_ids[] = {
 174        { .compatible = "fsl,imx21-audmux", .data = (void *)IMX21_AUDMUX, },
 175        { .compatible = "fsl,imx31-audmux", .data = (void *)IMX31_AUDMUX, },
 176        { /* sentinel */ }
 177};
 178MODULE_DEVICE_TABLE(of, imx_audmux_dt_ids);
 179
 180static const uint8_t port_mapping[] = {
 181        0x0, 0x4, 0x8, 0x10, 0x14, 0x1c,
 182};
 183
 184int imx_audmux_v1_configure_port(unsigned int port, unsigned int pcr)
 185{
 186        if (audmux_type != IMX21_AUDMUX)
 187                return -EINVAL;
 188
 189        if (!audmux_base)
 190                return -ENOSYS;
 191
 192        if (port >= ARRAY_SIZE(port_mapping))
 193                return -EINVAL;
 194
 195        writel(pcr, audmux_base + port_mapping[port]);
 196
 197        return 0;
 198}
 199EXPORT_SYMBOL_GPL(imx_audmux_v1_configure_port);
 200
 201int imx_audmux_v2_configure_port(unsigned int port, unsigned int ptcr,
 202                unsigned int pdcr)
 203{
 204        int ret;
 205
 206        if (audmux_type != IMX31_AUDMUX)
 207                return -EINVAL;
 208
 209        if (!audmux_base)
 210                return -ENOSYS;
 211
 212        if (audmux_clk) {
 213                ret = clk_prepare_enable(audmux_clk);
 214                if (ret)
 215                        return ret;
 216        }
 217
 218        writel(ptcr, audmux_base + IMX_AUDMUX_V2_PTCR(port));
 219        writel(pdcr, audmux_base + IMX_AUDMUX_V2_PDCR(port));
 220
 221        if (audmux_clk)
 222                clk_disable_unprepare(audmux_clk);
 223
 224        return 0;
 225}
 226EXPORT_SYMBOL_GPL(imx_audmux_v2_configure_port);
 227
 228static int imx_audmux_parse_dt_defaults(struct platform_device *pdev,
 229                struct device_node *of_node)
 230{
 231        struct device_node *child;
 232
 233        for_each_available_child_of_node(of_node, child) {
 234                unsigned int port;
 235                unsigned int ptcr = 0;
 236                unsigned int pdcr = 0;
 237                unsigned int pcr = 0;
 238                unsigned int val;
 239                int ret;
 240                int i = 0;
 241
 242                ret = of_property_read_u32(child, "fsl,audmux-port", &port);
 243                if (ret) {
 244                        dev_warn(&pdev->dev, "Failed to get fsl,audmux-port of child node \"%pOF\"\n",
 245                                        child);
 246                        continue;
 247                }
 248                if (!of_property_read_bool(child, "fsl,port-config")) {
 249                        dev_warn(&pdev->dev, "child node \"%pOF\" does not have property fsl,port-config\n",
 250                                        child);
 251                        continue;
 252                }
 253
 254                for (i = 0; (ret = of_property_read_u32_index(child,
 255                                        "fsl,port-config", i, &val)) == 0;
 256                                ++i) {
 257                        if (audmux_type == IMX31_AUDMUX) {
 258                                if (i % 2)
 259                                        pdcr |= val;
 260                                else
 261                                        ptcr |= val;
 262                        } else {
 263                                pcr |= val;
 264                        }
 265                }
 266
 267                if (ret != -EOVERFLOW) {
 268                        dev_err(&pdev->dev, "Failed to read u32 at index %d of child %pOF\n",
 269                                        i, child);
 270                        continue;
 271                }
 272
 273                if (audmux_type == IMX31_AUDMUX) {
 274                        if (i % 2) {
 275                                dev_err(&pdev->dev, "One pdcr value is missing in child node %pOF\n",
 276                                                child);
 277                                continue;
 278                        }
 279                        imx_audmux_v2_configure_port(port, ptcr, pdcr);
 280                } else {
 281                        imx_audmux_v1_configure_port(port, pcr);
 282                }
 283        }
 284
 285        return 0;
 286}
 287
 288static int imx_audmux_probe(struct platform_device *pdev)
 289{
 290        audmux_base = devm_platform_ioremap_resource(pdev, 0);
 291        if (IS_ERR(audmux_base))
 292                return PTR_ERR(audmux_base);
 293
 294        audmux_clk = devm_clk_get(&pdev->dev, "audmux");
 295        if (IS_ERR(audmux_clk)) {
 296                dev_dbg(&pdev->dev, "cannot get clock: %ld\n",
 297                                PTR_ERR(audmux_clk));
 298                audmux_clk = NULL;
 299        }
 300
 301        audmux_type = (enum imx_audmux_type)of_device_get_match_data(&pdev->dev);
 302
 303        switch (audmux_type) {
 304        case IMX31_AUDMUX:
 305                audmux_debugfs_init();
 306                reg_max = 14;
 307                break;
 308        case IMX21_AUDMUX:
 309                reg_max = 6;
 310                break;
 311        default:
 312                dev_err(&pdev->dev, "unsupported version!\n");
 313                return -EINVAL;
 314        }
 315
 316        regcache = devm_kzalloc(&pdev->dev, sizeof(u32) * reg_max, GFP_KERNEL);
 317        if (!regcache)
 318                return -ENOMEM;
 319
 320        imx_audmux_parse_dt_defaults(pdev, pdev->dev.of_node);
 321
 322        return 0;
 323}
 324
 325static int imx_audmux_remove(struct platform_device *pdev)
 326{
 327        if (audmux_type == IMX31_AUDMUX)
 328                audmux_debugfs_remove();
 329
 330        return 0;
 331}
 332
 333#ifdef CONFIG_PM_SLEEP
 334static int imx_audmux_suspend(struct device *dev)
 335{
 336        int i;
 337
 338        clk_prepare_enable(audmux_clk);
 339
 340        for (i = 0; i < reg_max; i++)
 341                regcache[i] = readl(audmux_base + i * 4);
 342
 343        clk_disable_unprepare(audmux_clk);
 344
 345        return 0;
 346}
 347
 348static int imx_audmux_resume(struct device *dev)
 349{
 350        int i;
 351
 352        clk_prepare_enable(audmux_clk);
 353
 354        for (i = 0; i < reg_max; i++)
 355                writel(regcache[i], audmux_base + i * 4);
 356
 357        clk_disable_unprepare(audmux_clk);
 358
 359        return 0;
 360}
 361#endif /* CONFIG_PM_SLEEP */
 362
 363static const struct dev_pm_ops imx_audmux_pm = {
 364        SET_SYSTEM_SLEEP_PM_OPS(imx_audmux_suspend, imx_audmux_resume)
 365};
 366
 367static struct platform_driver imx_audmux_driver = {
 368        .probe          = imx_audmux_probe,
 369        .remove         = imx_audmux_remove,
 370        .driver = {
 371                .name   = DRIVER_NAME,
 372                .pm = &imx_audmux_pm,
 373                .of_match_table = imx_audmux_dt_ids,
 374        }
 375};
 376
 377static int __init imx_audmux_init(void)
 378{
 379        return platform_driver_register(&imx_audmux_driver);
 380}
 381subsys_initcall(imx_audmux_init);
 382
 383static void __exit imx_audmux_exit(void)
 384{
 385        platform_driver_unregister(&imx_audmux_driver);
 386}
 387module_exit(imx_audmux_exit);
 388
 389MODULE_DESCRIPTION("Freescale i.MX AUDMUX driver");
 390MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
 391MODULE_LICENSE("GPL v2");
 392MODULE_ALIAS("platform:" DRIVER_NAME);
 393