sound/pci/oxygen/oxygen_io.c

   1 /*
   2  * C-Media CMI8788 driver - helper functions
   3  *
   4  * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
   5  *
   6  *
   7  *  This driver is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License, version 2.
   9  *
  10  *  This driver is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this driver; if not, write to the Free Software
  17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  18  */
  19
  20 #include <linux/delay.h>
  21 #include <linux/sched.h>
  22 #include <sound/core.h>
  23 #include <asm/io.h>
  24 #include "oxygen.h"
  25
  26 u8 oxygen_read8(struct oxygen *chip, unsigned int reg)
  27 {
  28         return inb(chip->addr + reg);
  29 }
  30 EXPORT_SYMBOL(oxygen_read8);
  31
  32 u16 oxygen_read16(struct oxygen *chip, unsigned int reg)
  33 {
  34         return inw(chip->addr + reg);
  35 }
  36 EXPORT_SYMBOL(oxygen_read16);
  37
  38 u32 oxygen_read32(struct oxygen *chip, unsigned int reg)
  39 {
  40         return inl(chip->addr + reg);
  41 }
  42 EXPORT_SYMBOL(oxygen_read32);
  43
  44 void oxygen_write8(struct oxygen *chip, unsigned int reg, u8 value)
  45 {
  46         outb(value, chip->addr + reg);
  47 }
  48 EXPORT_SYMBOL(oxygen_write8);
  49
  50 void oxygen_write16(struct oxygen *chip, unsigned int reg, u16 value)
  51 {
  52         outw(value, chip->addr + reg);
  53 }
  54 EXPORT_SYMBOL(oxygen_write16);
  55
  56 void oxygen_write32(struct oxygen *chip, unsigned int reg, u32 value)
  57 {
  58         outl(value, chip->addr + reg);
  59 }
  60 EXPORT_SYMBOL(oxygen_write32);
  61
  62 void oxygen_write8_masked(struct oxygen *chip, unsigned int reg,
  63                           u8 value, u8 mask)
  64 {
  65         u8 tmp = inb(chip->addr + reg);
  66         outb((tmp & ~mask) | (value & mask), chip->addr + reg);
  67 }
  68 EXPORT_SYMBOL(oxygen_write8_masked);
  69
  70 void oxygen_write16_masked(struct oxygen *chip, unsigned int reg,
  71                            u16 value, u16 mask)
  72 {
  73         u16 tmp = inw(chip->addr + reg);
  74         outw((tmp & ~mask) | (value & mask), chip->addr + reg);
  75 }
  76 EXPORT_SYMBOL(oxygen_write16_masked);
  77
  78 void oxygen_write32_masked(struct oxygen *chip, unsigned int reg,
  79                            u32 value, u32 mask)
  80 {
  81         u32 tmp = inl(chip->addr + reg);
  82         outl((tmp & ~mask) | (value & mask), chip->addr + reg);
  83 }
  84 EXPORT_SYMBOL(oxygen_write32_masked);
  85
  86 static int oxygen_ac97_wait(struct oxygen *chip, unsigned int mask)
  87 {
  88         u8 status = 0;
  89
  90         /*
  91          * Reading the status register also clears the bits, so we have to save
  92          * the read bits in status.
  93          */
  94         wait_event_timeout(chip->ac97_waitqueue,
  95                            ({ status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
  96                               status & mask; }),
  97                            msecs_to_jiffies(1) + 1);
  98         /*
  99          * Check even after a timeout because this function should not require
 100          * the AC'97 interrupt to be enabled.
 101          */
 102         status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
 103         return status & mask ? 0 : -EIO;
 104 }
 105
 106 /*
 107  * About 10% of AC'97 register reads or writes fail to complete, but even those
 108  * where the controller indicates completion aren't guaranteed to have actually
 109  * happened.
 110  *
 111  * It's hard to assign blame to either the controller or the codec because both
 112  * were made by C-Media ...
 113  */
 114
 115 void oxygen_write_ac97(struct oxygen *chip, unsigned int codec,
 116                        unsigned int index, u16 data)
 117 {
 118         unsigned int count, succeeded;
 119         u32 reg;
 120
 121         reg = data;
 122         reg |= index << OXYGEN_AC97_REG_ADDR_SHIFT;
 123         reg |= OXYGEN_AC97_REG_DIR_WRITE;
 124         reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
 125         succeeded = 0;
 126         for (count = 5; count > 0; --count) {
 127                 udelay(5);
 128                 oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
 129                 /* require two "completed" writes, just to be sure */
 130                 if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_WRITE_DONE) >= 0 &&
 131                     ++succeeded >= 2)
 132                         return;
 133         }
 134         snd_printk(KERN_ERR "AC'97 write timeout\n");
 135 }
 136 EXPORT_SYMBOL(oxygen_write_ac97);
 137
 138 u16 oxygen_read_ac97(struct oxygen *chip, unsigned int codec,
 139                      unsigned int index)
 140 {
 141         unsigned int count;
 142         unsigned int last_read = UINT_MAX;
 143         u32 reg;
 144
 145         reg = index << OXYGEN_AC97_REG_ADDR_SHIFT;
 146         reg |= OXYGEN_AC97_REG_DIR_READ;
 147         reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
 148         for (count = 5; count > 0; --count) {
 149                 udelay(5);
 150                 oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
 151                 udelay(10);
 152                 if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_READ_DONE) >= 0) {
 153                         u16 value = oxygen_read16(chip, OXYGEN_AC97_REGS);
 154                         /* we require two consecutive reads of the same value */
 155                         if (value == last_read)
 156                                 return value;
 157                         last_read = value;
 158                         /*
 159                          * Invert the register value bits to make sure that two
 160                          * consecutive unsuccessful reads do not return the same
 161                          * value.
 162                          */
 163                         reg ^= 0xffff;
 164                 }
 165         }
 166         snd_printk(KERN_ERR "AC'97 read timeout on codec %u\n", codec);
 167         return 0;
 168 }
 169 EXPORT_SYMBOL(oxygen_read_ac97);
 170
 171 void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
 172                               unsigned int index, u16 data, u16 mask)
 173 {
 174         u16 value = oxygen_read_ac97(chip, codec, index);
 175         value &= ~mask;
 176         value |= data & mask;
 177         oxygen_write_ac97(chip, codec, index, value);
 178 }
 179 EXPORT_SYMBOL(oxygen_write_ac97_masked);
 180
 181 void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
 182 {
 183         unsigned int count;
 184
 185         /* should not need more than 7.68 us (24 * 320 ns) */
 186         count = 10;
 187         while ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) & OXYGEN_SPI_BUSY)
 188                && count > 0) {
 189                 udelay(1);
 190                 --count;
 191         }
 192
 193         oxygen_write8(chip, OXYGEN_SPI_DATA1, data);
 194         oxygen_write8(chip, OXYGEN_SPI_DATA2, data >> 8);
 195         if (control & OXYGEN_SPI_DATA_LENGTH_3)
 196                 oxygen_write8(chip, OXYGEN_SPI_DATA3, data >> 16);
 197         oxygen_write8(chip, OXYGEN_SPI_CONTROL, control);
 198 }
 199 EXPORT_SYMBOL(oxygen_write_spi);
 200
 201 void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data)
 202 {
 203         unsigned long timeout;
 204
 205         /* should not need more than about 300 us */
 206         timeout = jiffies + msecs_to_jiffies(1);
 207         do {
 208                 if (!(oxygen_read16(chip, OXYGEN_2WIRE_BUS_STATUS)
 209                       & OXYGEN_2WIRE_BUSY))
 210                         break;
 211                 udelay(1);
 212                 cond_resched();
 213         } while (time_after_eq(timeout, jiffies));
 214
 215         oxygen_write8(chip, OXYGEN_2WIRE_MAP, map);
 216         oxygen_write8(chip, OXYGEN_2WIRE_DATA, data);
 217         oxygen_write8(chip, OXYGEN_2WIRE_CONTROL,
 218                       device | OXYGEN_2WIRE_DIR_WRITE);
 219 }
 220 EXPORT_SYMBOL(oxygen_write_i2c);