drivers/mfd/mcp-sa11x0.c

   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
  33 struct mcp_sa11x0 {
  34         u32     mccr0;
  35         u32     mccr1;
  36 };
  37
  38 #define priv(mcp)       ((struct mcp_sa11x0 *)mcp_priv(mcp))
  39
  40 static void
  41 mcp_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
  52 static void
  53 mcp_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  */
  70 static void
  71 mcp_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  */
  96 static unsigned int
  97 mcp_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
 118 static void mcp_sa11x0_enable(struct mcp *mcp)
 119 {
 120         Ser4MCSR = -1;
 121         Ser4MCCR0 |= MCCR0_MCE;
 122 }
 123
 124 static void mcp_sa11x0_disable(struct mcp *mcp)
 125 {
 126         Ser4MCCR0 &= ~MCCR0_MCE;
 127 }
 128
 129 /*
 130  * Our methods.
 131  */
 132 static 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
 141 static 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
 210 static 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
 221 static 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
 232 static 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  */
 245 MODULE_ALIAS("platform:sa11x0-mcp");
 246
 247 static 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  */
 260 static int __init mcp_sa11x0_init(void)
 261 {
 262         return platform_driver_register(&mcp_sa11x0_driver);
 263 }
 264
 265 static void __exit mcp_sa11x0_exit(void)
 266 {
 267         platform_driver_unregister(&mcp_sa11x0_driver);
 268 }
 269
 270 module_init(mcp_sa11x0_init);
 271 module_exit(mcp_sa11x0_exit);
 272
 273 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 274 MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
 275 MODULE_LICENSE("GPL");