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/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
  32 struct mcp_sa11x0 {
  33         u32     mccr0;
  34         u32     mccr1;
  35 };
  36
  37 #define priv(mcp)       ((struct mcp_sa11x0 *)mcp_priv(mcp))
  38
  39 static void
  40 mcp_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
  51 static void
  52 mcp_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  */
  69 static void
  70 mcp_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  */
  95 static unsigned int
  96 mcp_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
 117 static void mcp_sa11x0_enable(struct mcp *mcp)
 118 {
 119         Ser4MCSR = -1;
 120         Ser4MCCR0 |= MCCR0_MCE;
 121 }
 122
 123 static void mcp_sa11x0_disable(struct mcp *mcp)
 124 {
 125         Ser4MCCR0 &= ~MCCR0_MCE;
 126 }
 127
 128 /*
 129  * Our methods.
 130  */
 131 static 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
 140 static 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
 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");