linux/sound/arm/pxa2xx-ac97-lib.c
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   1/*
   2 * Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
   3 * which contain:
   4 *
   5 * Author:      Nicolas Pitre
   6 * Created:     Dec 02, 2004
   7 * Copyright:   MontaVista Software Inc.
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/platform_device.h>
  16#include <linux/interrupt.h>
  17#include <linux/clk.h>
  18#include <linux/delay.h>
  19#include <linux/module.h>
  20#include <linux/io.h>
  21#include <linux/gpio.h>
  22
  23#include <sound/ac97_codec.h>
  24#include <sound/pxa2xx-lib.h>
  25
  26#include <mach/irqs.h>
  27#include <mach/regs-ac97.h>
  28#include <mach/audio.h>
  29
  30static DEFINE_MUTEX(car_mutex);
  31static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
  32static volatile long gsr_bits;
  33static struct clk *ac97_clk;
  34static struct clk *ac97conf_clk;
  35static int reset_gpio;
  36
  37extern void pxa27x_assert_ac97reset(int reset_gpio, int on);
  38
  39/*
  40 * Beware PXA27x bugs:
  41 *
  42 *   o Slot 12 read from modem space will hang controller.
  43 *   o CDONE, SDONE interrupt fails after any slot 12 IO.
  44 *
  45 * We therefore have an hybrid approach for waiting on SDONE (interrupt or
  46 * 1 jiffy timeout if interrupt never comes).
  47 */
  48
  49unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
  50{
  51        unsigned short val = -1;
  52        volatile u32 *reg_addr;
  53
  54        mutex_lock(&car_mutex);
  55
  56        /* set up primary or secondary codec space */
  57        if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
  58                reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
  59        else
  60                reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
  61        reg_addr += (reg >> 1);
  62
  63        /* start read access across the ac97 link */
  64        GSR = GSR_CDONE | GSR_SDONE;
  65        gsr_bits = 0;
  66        val = *reg_addr;
  67        if (reg == AC97_GPIO_STATUS)
  68                goto out;
  69        if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
  70            !((GSR | gsr_bits) & GSR_SDONE)) {
  71                printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
  72                                __func__, reg, GSR | gsr_bits);
  73                val = -1;
  74                goto out;
  75        }
  76
  77        /* valid data now */
  78        GSR = GSR_CDONE | GSR_SDONE;
  79        gsr_bits = 0;
  80        val = *reg_addr;
  81        /* but we've just started another cycle... */
  82        wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
  83
  84out:    mutex_unlock(&car_mutex);
  85        return val;
  86}
  87EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
  88
  89void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
  90                        unsigned short val)
  91{
  92        volatile u32 *reg_addr;
  93
  94        mutex_lock(&car_mutex);
  95
  96        /* set up primary or secondary codec space */
  97        if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
  98                reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
  99        else
 100                reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
 101        reg_addr += (reg >> 1);
 102
 103        GSR = GSR_CDONE | GSR_SDONE;
 104        gsr_bits = 0;
 105        *reg_addr = val;
 106        if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
 107            !((GSR | gsr_bits) & GSR_CDONE))
 108                printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
 109                                __func__, reg, GSR | gsr_bits);
 110
 111        mutex_unlock(&car_mutex);
 112}
 113EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
 114
 115#ifdef CONFIG_PXA25x
 116static inline void pxa_ac97_warm_pxa25x(void)
 117{
 118        gsr_bits = 0;
 119
 120        GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
 121        wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
 122}
 123
 124static inline void pxa_ac97_cold_pxa25x(void)
 125{
 126        GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
 127        GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
 128
 129        gsr_bits = 0;
 130
 131        GCR = GCR_COLD_RST;
 132        GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
 133        wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
 134}
 135#endif
 136
 137#ifdef CONFIG_PXA27x
 138static inline void pxa_ac97_warm_pxa27x(void)
 139{
 140        gsr_bits = 0;
 141
 142        /* warm reset broken on Bulverde, so manually keep AC97 reset high */
 143        pxa27x_assert_ac97reset(reset_gpio, 1);
 144        udelay(10);
 145        GCR |= GCR_WARM_RST;
 146        pxa27x_assert_ac97reset(reset_gpio, 0);
 147        udelay(500);
 148}
 149
 150static inline void pxa_ac97_cold_pxa27x(void)
 151{
 152        unsigned int timeout;
 153
 154        GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
 155        GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
 156
 157        gsr_bits = 0;
 158
 159        /* PXA27x Developers Manual section 13.5.2.2.1 */
 160        clk_enable(ac97conf_clk);
 161        udelay(5);
 162        clk_disable(ac97conf_clk);
 163        GCR = GCR_COLD_RST | GCR_WARM_RST;
 164        timeout = 100;     /* wait for the codec-ready bit to be set */
 165        while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
 166                mdelay(1);
 167}
 168#endif
 169
 170#ifdef CONFIG_PXA3xx
 171static inline void pxa_ac97_warm_pxa3xx(void)
 172{
 173        int timeout = 100;
 174
 175        gsr_bits = 0;
 176
 177        /* Can't use interrupts */
 178        GCR |= GCR_WARM_RST;
 179        while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
 180                mdelay(1);
 181}
 182
 183static inline void pxa_ac97_cold_pxa3xx(void)
 184{
 185        int timeout = 1000;
 186
 187        /* Hold CLKBPB for 100us */
 188        GCR = 0;
 189        GCR = GCR_CLKBPB;
 190        udelay(100);
 191        GCR = 0;
 192
 193        GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
 194        GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
 195
 196        gsr_bits = 0;
 197
 198        /* Can't use interrupts on PXA3xx */
 199        GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
 200
 201        GCR = GCR_WARM_RST | GCR_COLD_RST;
 202        while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
 203                mdelay(10);
 204}
 205#endif
 206
 207bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
 208{
 209        unsigned long gsr;
 210
 211#ifdef CONFIG_PXA25x
 212        if (cpu_is_pxa25x())
 213                pxa_ac97_warm_pxa25x();
 214        else
 215#endif
 216#ifdef CONFIG_PXA27x
 217        if (cpu_is_pxa27x())
 218                pxa_ac97_warm_pxa27x();
 219        else
 220#endif
 221#ifdef CONFIG_PXA3xx
 222        if (cpu_is_pxa3xx())
 223                pxa_ac97_warm_pxa3xx();
 224        else
 225#endif
 226                BUG();
 227        gsr = GSR | gsr_bits;
 228        if (!(gsr & (GSR_PCR | GSR_SCR))) {
 229                printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
 230                                 __func__, gsr);
 231
 232                return false;
 233        }
 234
 235        return true;
 236}
 237EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
 238
 239bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
 240{
 241        unsigned long gsr;
 242
 243#ifdef CONFIG_PXA25x
 244        if (cpu_is_pxa25x())
 245                pxa_ac97_cold_pxa25x();
 246        else
 247#endif
 248#ifdef CONFIG_PXA27x
 249        if (cpu_is_pxa27x())
 250                pxa_ac97_cold_pxa27x();
 251        else
 252#endif
 253#ifdef CONFIG_PXA3xx
 254        if (cpu_is_pxa3xx())
 255                pxa_ac97_cold_pxa3xx();
 256        else
 257#endif
 258                BUG();
 259
 260        gsr = GSR | gsr_bits;
 261        if (!(gsr & (GSR_PCR | GSR_SCR))) {
 262                printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
 263                                 __func__, gsr);
 264
 265                return false;
 266        }
 267
 268        return true;
 269}
 270EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
 271
 272
 273void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
 274{
 275        GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
 276        GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
 277}
 278EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
 279
 280static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
 281{
 282        long status;
 283
 284        status = GSR;
 285        if (status) {
 286                GSR = status;
 287                gsr_bits |= status;
 288                wake_up(&gsr_wq);
 289
 290                /* Although we don't use those we still need to clear them
 291                   since they tend to spuriously trigger when MMC is used
 292                   (hardware bug? go figure)... */
 293                if (cpu_is_pxa27x()) {
 294                        MISR = MISR_EOC;
 295                        PISR = PISR_EOC;
 296                        MCSR = MCSR_EOC;
 297                }
 298
 299                return IRQ_HANDLED;
 300        }
 301
 302        return IRQ_NONE;
 303}
 304
 305#ifdef CONFIG_PM
 306int pxa2xx_ac97_hw_suspend(void)
 307{
 308        GCR |= GCR_ACLINK_OFF;
 309        clk_disable(ac97_clk);
 310        return 0;
 311}
 312EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
 313
 314int pxa2xx_ac97_hw_resume(void)
 315{
 316        clk_enable(ac97_clk);
 317        return 0;
 318}
 319EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
 320#endif
 321
 322int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
 323{
 324        int ret;
 325        pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
 326
 327        if (pdata) {
 328                switch (pdata->reset_gpio) {
 329                case 95:
 330                case 113:
 331                        reset_gpio = pdata->reset_gpio;
 332                        break;
 333                case 0:
 334                        reset_gpio = 113;
 335                        break;
 336                case -1:
 337                        break;
 338                default:
 339                        dev_err(&dev->dev, "Invalid reset GPIO %d\n",
 340                                pdata->reset_gpio);
 341                }
 342        } else {
 343                if (cpu_is_pxa27x())
 344                        reset_gpio = 113;
 345        }
 346
 347        if (cpu_is_pxa27x()) {
 348                /*
 349                 * This gpio is needed for a work-around to a bug in the ac97
 350                 * controller during warm reset.  The direction and level is set
 351                 * here so that it is an output driven high when switching from
 352                 * AC97_nRESET alt function to generic gpio.
 353                 */
 354                ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
 355                                       "pxa27x ac97 reset");
 356                if (ret < 0) {
 357                        pr_err("%s: gpio_request_one() failed: %d\n",
 358                               __func__, ret);
 359                        goto err_conf;
 360                }
 361                pxa27x_assert_ac97reset(reset_gpio, 0);
 362
 363                ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
 364                if (IS_ERR(ac97conf_clk)) {
 365                        ret = PTR_ERR(ac97conf_clk);
 366                        ac97conf_clk = NULL;
 367                        goto err_conf;
 368                }
 369        }
 370
 371        ac97_clk = clk_get(&dev->dev, "AC97CLK");
 372        if (IS_ERR(ac97_clk)) {
 373                ret = PTR_ERR(ac97_clk);
 374                ac97_clk = NULL;
 375                goto err_clk;
 376        }
 377
 378        ret = clk_enable(ac97_clk);
 379        if (ret)
 380                goto err_clk2;
 381
 382        ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
 383        if (ret < 0)
 384                goto err_irq;
 385
 386        return 0;
 387
 388err_irq:
 389        GCR |= GCR_ACLINK_OFF;
 390err_clk2:
 391        clk_put(ac97_clk);
 392        ac97_clk = NULL;
 393err_clk:
 394        if (ac97conf_clk) {
 395                clk_put(ac97conf_clk);
 396                ac97conf_clk = NULL;
 397        }
 398err_conf:
 399        return ret;
 400}
 401EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
 402
 403void pxa2xx_ac97_hw_remove(struct platform_device *dev)
 404{
 405        if (cpu_is_pxa27x())
 406                gpio_free(reset_gpio);
 407        GCR |= GCR_ACLINK_OFF;
 408        free_irq(IRQ_AC97, NULL);
 409        if (ac97conf_clk) {
 410                clk_put(ac97conf_clk);
 411                ac97conf_clk = NULL;
 412        }
 413        clk_disable(ac97_clk);
 414        clk_put(ac97_clk);
 415        ac97_clk = NULL;
 416}
 417EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
 418
 419MODULE_AUTHOR("Nicolas Pitre");
 420MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
 421MODULE_LICENSE("GPL");
 422
 423
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