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/platform_device.h>
  21#include <linux/mfd/mcp.h>
  22
  23#include <mach/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
  32struct mcp_sa11x0 {
  33        u32     mccr0;
  34        u32     mccr1;
  35};
  36
  37#define priv(mcp)       ((struct mcp_sa11x0 *)mcp_priv(mcp))
  38
  39static void
  40mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
  41{
  42        unsigned int mccr0;
  43
  44        divisor /= 32;
  45
  46        mccr0 = Ser4MCCR0 & ~0x00007f00;
  47        mccr0 |= divisor << 8;
  48        Ser4MCCR0 = mccr0;
  49}
  50
  51static void
  52mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
  53{
  54        unsigned int mccr0;
  55
  56        divisor /= 32;
  57
  58        mccr0 = Ser4MCCR0 & ~0x0000007f;
  59        mccr0 |= divisor;
  60        Ser4MCCR0 = mccr0;
  61}
  62
  63/*
  64 * Write data to the device.  The bit should be set after 3 subframe
  65 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
  66 * We really should try doing something more productive while we
  67 * wait.
  68 */
  69static void
  70mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
  71{
  72        int ret = -ETIME;
  73        int i;
  74
  75        Ser4MCDR2 = reg << 17 | MCDR2_Wr | (val & 0xffff);
  76
  77        for (i = 0; i < 2; i++) {
  78                udelay(mcp->rw_timeout);
  79                if (Ser4MCSR & MCSR_CWC) {
  80                        ret = 0;
  81                        break;
  82                }
  83        }
  84
  85        if (ret < 0)
  86                printk(KERN_WARNING "mcp: write timed out\n");
  87}
  88
  89/*
  90 * Read data from the device.  The bit should be set after 3 subframe
  91 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
  92 * We really should try doing something more productive while we
  93 * wait.
  94 */
  95static unsigned int
  96mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
  97{
  98        int ret = -ETIME;
  99        int i;
 100
 101        Ser4MCDR2 = reg << 17 | MCDR2_Rd;
 102
 103        for (i = 0; i < 2; i++) {
 104                udelay(mcp->rw_timeout);
 105                if (Ser4MCSR & MCSR_CRC) {
 106                        ret = Ser4MCDR2 & 0xffff;
 107                        break;
 108                }
 109        }
 110
 111        if (ret < 0)
 112                printk(KERN_WARNING "mcp: read timed out\n");
 113
 114        return ret;
 115}
 116
 117static void mcp_sa11x0_enable(struct mcp *mcp)
 118{
 119        Ser4MCSR = -1;
 120        Ser4MCCR0 |= MCCR0_MCE;
 121}
 122
 123static void mcp_sa11x0_disable(struct mcp *mcp)
 124{
 125        Ser4MCCR0 &= ~MCCR0_MCE;
 126}
 127
 128/*
 129 * Our methods.
 130 */
 131static struct mcp_ops mcp_sa11x0 = {
 132        .set_telecom_divisor    = mcp_sa11x0_set_telecom_divisor,
 133        .set_audio_divisor      = mcp_sa11x0_set_audio_divisor,
 134        .reg_write              = mcp_sa11x0_write,
 135        .reg_read               = mcp_sa11x0_read,
 136        .enable                 = mcp_sa11x0_enable,
 137        .disable                = mcp_sa11x0_disable,
 138};
 139
 140static int mcp_sa11x0_probe(struct platform_device *pdev)
 141{
 142        struct mcp_plat_data *data = pdev->dev.platform_data;
 143        struct mcp *mcp;
 144        int ret;
 145
 146        if (!data)
 147                return -ENODEV;
 148
 149        if (!request_mem_region(0x80060000, 0x60, "sa11x0-mcp"))
 150                return -EBUSY;
 151
 152        mcp = mcp_host_alloc(&pdev->dev, sizeof(struct mcp_sa11x0));
 153        if (!mcp) {
 154                ret = -ENOMEM;
 155                goto release;
 156        }
 157
 158        mcp->owner              = THIS_MODULE;
 159        mcp->ops                = &mcp_sa11x0;
 160        mcp->sclk_rate          = data->sclk_rate;
 161        mcp->dma_audio_rd       = DMA_Ser4MCP0Rd;
 162        mcp->dma_audio_wr       = DMA_Ser4MCP0Wr;
 163        mcp->dma_telco_rd       = DMA_Ser4MCP1Rd;
 164        mcp->dma_telco_wr       = DMA_Ser4MCP1Wr;
 165        mcp->gpio_base          = data->gpio_base;
 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