linux/drivers/mfd/mcp-sa11x0.c
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   1/*
   2 *  linux/drivers/mfd/mcp-sa11x0.c
   3 *
   4 *  Copyright (C) 2001-2005 Russell King
   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 as published by
   8 * the Free Software Foundation; either version 2 of the License.
   9 *
  10 *  SA11x0 MCP (Multimedia Communications Port) driver.
  11 *
  12 *  MCP read/write timeouts from Jordi Colomer, rehacked by rmk.
  13 */
  14#include <linux/module.h>
  15#include <linux/init.h>
  16#include <linux/errno.h>
  17#include <linux/kernel.h>
  18#include <linux/delay.h>
  19#include <linux/spinlock.h>
  20#include <linux/slab.h>
  21#include <linux/platform_device.h>
  22
  23#include <asm/dma.h>
  24#include <mach/hardware.h>
  25#include <asm/mach-types.h>
  26#include <asm/system.h>
  27#include <mach/mcp.h>
  28
  29#include <mach/assabet.h>
  30
  31#include "mcp.h"
  32
  33struct mcp_sa11x0 {
  34        u32     mccr0;
  35        u32     mccr1;
  36};
  37
  38#define priv(mcp)       ((struct mcp_sa11x0 *)mcp_priv(mcp))
  39
  40static void
  41mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
  42{
  43        unsigned int mccr0;
  44
  45        divisor /= 32;
  46
  47        mccr0 = Ser4MCCR0 & ~0x00007f00;
  48        mccr0 |= divisor << 8;
  49        Ser4MCCR0 = mccr0;
  50}
  51
  52static void
  53mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
  54{
  55        unsigned int mccr0;
  56
  57        divisor /= 32;
  58
  59        mccr0 = Ser4MCCR0 & ~0x0000007f;
  60        mccr0 |= divisor;
  61        Ser4MCCR0 = mccr0;
  62}
  63
  64/*
  65 * Write data to the device.  The bit should be set after 3 subframe
  66 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
  67 * We really should try doing something more productive while we
  68 * wait.
  69 */
  70static void
  71mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
  72{
  73        int ret = -ETIME;
  74        int i;
  75
  76        Ser4MCDR2 = reg << 17 | MCDR2_Wr | (val & 0xffff);
  77
  78        for (i = 0; i < 2; i++) {
  79                udelay(mcp->rw_timeout);
  80                if (Ser4MCSR & MCSR_CWC) {
  81                        ret = 0;
  82                        break;
  83                }
  84        }
  85
  86        if (ret < 0)
  87                printk(KERN_WARNING "mcp: write timed out\n");
  88}
  89
  90/*
  91 * Read data from the device.  The bit should be set after 3 subframe
  92 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
  93 * We really should try doing something more productive while we
  94 * wait.
  95 */
  96static unsigned int
  97mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
  98{
  99        int ret = -ETIME;
 100        int i;
 101
 102        Ser4MCDR2 = reg << 17 | MCDR2_Rd;
 103
 104        for (i = 0; i < 2; i++) {
 105                udelay(mcp->rw_timeout);
 106                if (Ser4MCSR & MCSR_CRC) {
 107                        ret = Ser4MCDR2 & 0xffff;
 108                        break;
 109                }
 110        }
 111
 112        if (ret < 0)
 113                printk(KERN_WARNING "mcp: read timed out\n");
 114
 115        return ret;
 116}
 117
 118static void mcp_sa11x0_enable(struct mcp *mcp)
 119{
 120        Ser4MCSR = -1;
 121        Ser4MCCR0 |= MCCR0_MCE;
 122}
 123
 124static void mcp_sa11x0_disable(struct mcp *mcp)
 125{
 126        Ser4MCCR0 &= ~MCCR0_MCE;
 127}
 128
 129/*
 130 * Our methods.
 131 */
 132static struct mcp_ops mcp_sa11x0 = {
 133        .set_telecom_divisor    = mcp_sa11x0_set_telecom_divisor,
 134        .set_audio_divisor      = mcp_sa11x0_set_audio_divisor,
 135        .reg_write              = mcp_sa11x0_write,
 136        .reg_read               = mcp_sa11x0_read,
 137        .enable                 = mcp_sa11x0_enable,
 138        .disable                = mcp_sa11x0_disable,
 139};
 140
 141static int mcp_sa11x0_probe(struct platform_device *pdev)
 142{
 143        struct mcp_plat_data *data = pdev->dev.platform_data;
 144        struct mcp *mcp;
 145        int ret;
 146
 147        if (!data)
 148                return -ENODEV;
 149
 150        if (!request_mem_region(0x80060000, 0x60, "sa11x0-mcp"))
 151                return -EBUSY;
 152
 153        mcp = mcp_host_alloc(&pdev->dev, sizeof(struct mcp_sa11x0));
 154        if (!mcp) {
 155                ret = -ENOMEM;
 156                goto release;
 157        }
 158
 159        mcp->owner              = THIS_MODULE;
 160        mcp->ops                = &mcp_sa11x0;
 161        mcp->sclk_rate          = data->sclk_rate;
 162        mcp->dma_audio_rd       = DMA_Ser4MCP0Rd;
 163        mcp->dma_audio_wr       = DMA_Ser4MCP0Wr;
 164        mcp->dma_telco_rd       = DMA_Ser4MCP1Rd;
 165        mcp->dma_telco_wr       = DMA_Ser4MCP1Wr;
 166
 167        platform_set_drvdata(pdev, mcp);
 168
 169        if (machine_is_assabet()) {
 170                ASSABET_BCR_set(ASSABET_BCR_CODEC_RST);
 171        }
 172
 173        /*
 174         * Setup the PPC unit correctly.
 175         */
 176        PPDR &= ~PPC_RXD4;
 177        PPDR |= PPC_TXD4 | PPC_SCLK | PPC_SFRM;
 178        PSDR |= PPC_RXD4;
 179        PSDR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
 180        PPSR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
 181
 182        /*
 183         * Initialise device.  Note that we initially
 184         * set the sampling rate to minimum.
 185         */
 186        Ser4MCSR = -1;
 187        Ser4MCCR1 = data->mccr1;
 188        Ser4MCCR0 = data->mccr0 | 0x7f7f;
 189
 190        /*
 191         * Calculate the read/write timeout (us) from the bit clock
 192         * rate.  This is the period for 3 64-bit frames.  Always
 193         * round this time up.
 194         */
 195        mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
 196                          mcp->sclk_rate;
 197
 198        ret = mcp_host_register(mcp);
 199        if (ret == 0)
 200                goto out;
 201
 202 release:
 203        release_mem_region(0x80060000, 0x60);
 204        platform_set_drvdata(pdev, NULL);
 205
 206 out:
 207        return ret;
 208}
 209
 210static int mcp_sa11x0_remove(struct platform_device *dev)
 211{
 212        struct mcp *mcp = platform_get_drvdata(dev);
 213
 214        platform_set_drvdata(dev, NULL);
 215        mcp_host_unregister(mcp);
 216        release_mem_region(0x80060000, 0x60);
 217
 218        return 0;
 219}
 220
 221static int mcp_sa11x0_suspend(struct platform_device *dev, pm_message_t state)
 222{
 223        struct mcp *mcp = platform_get_drvdata(dev);
 224
 225        priv(mcp)->mccr0 = Ser4MCCR0;
 226        priv(mcp)->mccr1 = Ser4MCCR1;
 227        Ser4MCCR0 &= ~MCCR0_MCE;
 228
 229        return 0;
 230}
 231
 232static int mcp_sa11x0_resume(struct platform_device *dev)
 233{
 234        struct mcp *mcp = platform_get_drvdata(dev);
 235
 236        Ser4MCCR1 = priv(mcp)->mccr1;
 237        Ser4MCCR0 = priv(mcp)->mccr0;
 238
 239        return 0;
 240}
 241
 242/*
 243 * The driver for the SA11x0 MCP port.
 244 */
 245MODULE_ALIAS("platform:sa11x0-mcp");
 246
 247static struct platform_driver mcp_sa11x0_driver = {
 248        .probe          = mcp_sa11x0_probe,
 249        .remove         = mcp_sa11x0_remove,
 250        .suspend        = mcp_sa11x0_suspend,
 251        .resume         = mcp_sa11x0_resume,
 252        .driver         = {
 253                .name   = "sa11x0-mcp",
 254        },
 255};
 256
 257/*
 258 * This needs re-working
 259 */
 260static int __init mcp_sa11x0_init(void)
 261{
 262        return platform_driver_register(&mcp_sa11x0_driver);
 263}
 264
 265static void __exit mcp_sa11x0_exit(void)
 266{
 267        platform_driver_unregister(&mcp_sa11x0_driver);
 268}
 269
 270module_init(mcp_sa11x0_init);
 271module_exit(mcp_sa11x0_exit);
 272
 273MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 274MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
 275MODULE_LICENSE("GPL");
 276