drivers/media/usb/stk1160/stk1160-ac97.c

   1 /*
   2  * STK1160 driver
   3  *
   4  * Copyright (C) 2012 Ezequiel Garcia
   5  * <elezegarcia--a.t--gmail.com>
   6  *
   7  * Copyright (C) 2016 Marcel Hasler
   8  * <mahasler--a.t--gmail.com>
   9  *
  10  * Based on Easycap driver by R.M. Thomas
  11  *      Copyright (C) 2010 R.M. Thomas
  12  *      <rmthomas--a.t--sciolus.org>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  */
  25
  26 #include <linux/delay.h>
  27
  28 #include "stk1160.h"
  29 #include "stk1160-reg.h"
  30
  31 static int stk1160_ac97_wait_transfer_complete(struct stk1160 *dev)
  32 {
  33         unsigned long timeout = jiffies + msecs_to_jiffies(STK1160_AC97_TIMEOUT);
  34         u8 value;
  35
  36         /* Wait for AC97 transfer to complete */
  37         while (time_is_after_jiffies(timeout)) {
  38                 stk1160_read_reg(dev, STK1160_AC97CTL_0, &value);
  39
  40                 if (!(value & (STK1160_AC97CTL_0_CR | STK1160_AC97CTL_0_CW)))
  41                         return 0;
  42
  43                 usleep_range(50, 100);
  44         }
  45
  46         stk1160_err("AC97 transfer took too long, this should never happen!");
  47         return -EBUSY;
  48 }
  49
  50 static void stk1160_write_ac97(struct stk1160 *dev, u16 reg, u16 value)
  51 {
  52         /* Set codec register address */
  53         stk1160_write_reg(dev, STK1160_AC97_ADDR, reg);
  54
  55         /* Set codec command */
  56         stk1160_write_reg(dev, STK1160_AC97_CMD, value & 0xff);
  57         stk1160_write_reg(dev, STK1160_AC97_CMD + 1, (value & 0xff00) >> 8);
  58
  59         /* Set command write bit to initiate write operation */
  60         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c);
  61
  62         /* Wait for command write bit to be cleared */
  63         stk1160_ac97_wait_transfer_complete(dev);
  64 }
  65
  66 #ifdef DEBUG
  67 static u16 stk1160_read_ac97(struct stk1160 *dev, u16 reg)
  68 {
  69         u8 vall = 0;
  70         u8 valh = 0;
  71
  72         /* Set codec register address */
  73         stk1160_write_reg(dev, STK1160_AC97_ADDR, reg);
  74
  75         /* Set command read bit to initiate read operation */
  76         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8b);
  77
  78         /* Wait for command read bit to be cleared */
  79         if (stk1160_ac97_wait_transfer_complete(dev) < 0)
  80                 return 0;
  81
  82
  83         /* Retrieve register value */
  84         stk1160_read_reg(dev, STK1160_AC97_CMD, &vall);
  85         stk1160_read_reg(dev, STK1160_AC97_CMD + 1, &valh);
  86
  87         return (valh << 8) | vall;
  88 }
  89
  90 void stk1160_ac97_dump_regs(struct stk1160 *dev)
  91 {
  92         u16 value;
  93
  94         value = stk1160_read_ac97(dev, 0x12); /* CD volume */
  95         stk1160_dbg("0x12 == 0x%04x", value);
  96
  97         value = stk1160_read_ac97(dev, 0x10); /* Line-in volume */
  98         stk1160_dbg("0x10 == 0x%04x", value);
  99
 100         value = stk1160_read_ac97(dev, 0x0e); /* MIC volume (mono) */
 101         stk1160_dbg("0x0e == 0x%04x", value);
 102
 103         value = stk1160_read_ac97(dev, 0x16); /* Aux volume */
 104         stk1160_dbg("0x16 == 0x%04x", value);
 105
 106         value = stk1160_read_ac97(dev, 0x1a); /* Record select */
 107         stk1160_dbg("0x1a == 0x%04x", value);
 108
 109         value = stk1160_read_ac97(dev, 0x02); /* Master volume */
 110         stk1160_dbg("0x02 == 0x%04x", value);
 111
 112         value = stk1160_read_ac97(dev, 0x1c); /* Record gain */
 113         stk1160_dbg("0x1c == 0x%04x", value);
 114 }
 115 #endif
 116
 117 static int stk1160_has_audio(struct stk1160 *dev)
 118 {
 119         u8 value;
 120
 121         stk1160_read_reg(dev, STK1160_POSV_L, &value);
 122         return !(value & STK1160_POSV_L_ACDOUT);
 123 }
 124
 125 static int stk1160_has_ac97(struct stk1160 *dev)
 126 {
 127         u8 value;
 128
 129         stk1160_read_reg(dev, STK1160_POSV_L, &value);
 130         return !(value & STK1160_POSV_L_ACSYNC);
 131 }
 132
 133 void stk1160_ac97_setup(struct stk1160 *dev)
 134 {
 135         if (!stk1160_has_audio(dev)) {
 136                 stk1160_info("Device doesn't support audio, skipping AC97 setup.");
 137                 return;
 138         }
 139
 140         if (!stk1160_has_ac97(dev)) {
 141                 stk1160_info("Device uses internal 8-bit ADC, skipping AC97 setup.");
 142                 return;
 143         }
 144
 145         /* Two-step reset AC97 interface and hardware codec */
 146         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x94);
 147         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c);
 148
 149         /* Set 16-bit audio data and choose L&R channel*/
 150         stk1160_write_reg(dev, STK1160_AC97CTL_1 + 2, 0x01);
 151         stk1160_write_reg(dev, STK1160_AC97CTL_1 + 3, 0x00);
 152
 153         /* Setup channels */
 154         stk1160_write_ac97(dev, 0x12, 0x8808); /* CD volume */
 155         stk1160_write_ac97(dev, 0x10, 0x0808); /* Line-in volume */
 156         stk1160_write_ac97(dev, 0x0e, 0x0008); /* MIC volume (mono) */
 157         stk1160_write_ac97(dev, 0x16, 0x0808); /* Aux volume */
 158         stk1160_write_ac97(dev, 0x1a, 0x0404); /* Record select */
 159         stk1160_write_ac97(dev, 0x02, 0x0000); /* Master volume */
 160         stk1160_write_ac97(dev, 0x1c, 0x0808); /* Record gain */
 161
 162 #ifdef DEBUG
 163         stk1160_ac97_dump_regs(dev);
 164 #endif
 165 }