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

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * STK1160 driver
   4  *
   5  * Copyright (C) 2012 Ezequiel Garcia
   6  * <elezegarcia--a.t--gmail.com>
   7  *
   8  * Copyright (C) 2016 Marcel Hasler
   9  * <mahasler--a.t--gmail.com>
  10  *
  11  * Based on Easycap driver by R.M. Thomas
  12  *      Copyright (C) 2010 R.M. Thomas
  13  *      <rmthomas--a.t--sciolus.org>
  14  */
  15
  16 #include <linux/delay.h>
  17
  18 #include "stk1160.h"
  19 #include "stk1160-reg.h"
  20
  21 static int stk1160_ac97_wait_transfer_complete(struct stk1160 *dev)
  22 {
  23         unsigned long timeout = jiffies + msecs_to_jiffies(STK1160_AC97_TIMEOUT);
  24         u8 value;
  25
  26         /* Wait for AC97 transfer to complete */
  27         while (time_is_after_jiffies(timeout)) {
  28                 stk1160_read_reg(dev, STK1160_AC97CTL_0, &value);
  29
  30                 if (!(value & (STK1160_AC97CTL_0_CR | STK1160_AC97CTL_0_CW)))
  31                         return 0;
  32
  33                 usleep_range(50, 100);
  34         }
  35
  36         stk1160_err("AC97 transfer took too long, this should never happen!");
  37         return -EBUSY;
  38 }
  39
  40 static void stk1160_write_ac97(struct stk1160 *dev, u16 reg, u16 value)
  41 {
  42         /* Set codec register address */
  43         stk1160_write_reg(dev, STK1160_AC97_ADDR, reg);
  44
  45         /* Set codec command */
  46         stk1160_write_reg(dev, STK1160_AC97_CMD, value & 0xff);
  47         stk1160_write_reg(dev, STK1160_AC97_CMD + 1, (value & 0xff00) >> 8);
  48
  49         /* Set command write bit to initiate write operation */
  50         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c);
  51
  52         /* Wait for command write bit to be cleared */
  53         stk1160_ac97_wait_transfer_complete(dev);
  54 }
  55
  56 #ifdef DEBUG
  57 static u16 stk1160_read_ac97(struct stk1160 *dev, u16 reg)
  58 {
  59         u8 vall = 0;
  60         u8 valh = 0;
  61
  62         /* Set codec register address */
  63         stk1160_write_reg(dev, STK1160_AC97_ADDR, reg);
  64
  65         /* Set command read bit to initiate read operation */
  66         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8b);
  67
  68         /* Wait for command read bit to be cleared */
  69         if (stk1160_ac97_wait_transfer_complete(dev) < 0)
  70                 return 0;
  71
  72
  73         /* Retrieve register value */
  74         stk1160_read_reg(dev, STK1160_AC97_CMD, &vall);
  75         stk1160_read_reg(dev, STK1160_AC97_CMD + 1, &valh);
  76
  77         return (valh << 8) | vall;
  78 }
  79
  80 void stk1160_ac97_dump_regs(struct stk1160 *dev)
  81 {
  82         u16 value;
  83
  84         value = stk1160_read_ac97(dev, 0x12); /* CD volume */
  85         stk1160_dbg("0x12 == 0x%04x", value);
  86
  87         value = stk1160_read_ac97(dev, 0x10); /* Line-in volume */
  88         stk1160_dbg("0x10 == 0x%04x", value);
  89
  90         value = stk1160_read_ac97(dev, 0x0e); /* MIC volume (mono) */
  91         stk1160_dbg("0x0e == 0x%04x", value);
  92
  93         value = stk1160_read_ac97(dev, 0x16); /* Aux volume */
  94         stk1160_dbg("0x16 == 0x%04x", value);
  95
  96         value = stk1160_read_ac97(dev, 0x1a); /* Record select */
  97         stk1160_dbg("0x1a == 0x%04x", value);
  98
  99         value = stk1160_read_ac97(dev, 0x02); /* Master volume */
 100         stk1160_dbg("0x02 == 0x%04x", value);
 101
 102         value = stk1160_read_ac97(dev, 0x1c); /* Record gain */
 103         stk1160_dbg("0x1c == 0x%04x", value);
 104 }
 105 #endif
 106
 107 static int stk1160_has_audio(struct stk1160 *dev)
 108 {
 109         u8 value;
 110
 111         stk1160_read_reg(dev, STK1160_POSV_L, &value);
 112         return !(value & STK1160_POSV_L_ACDOUT);
 113 }
 114
 115 static int stk1160_has_ac97(struct stk1160 *dev)
 116 {
 117         u8 value;
 118
 119         stk1160_read_reg(dev, STK1160_POSV_L, &value);
 120         return !(value & STK1160_POSV_L_ACSYNC);
 121 }
 122
 123 void stk1160_ac97_setup(struct stk1160 *dev)
 124 {
 125         if (!stk1160_has_audio(dev)) {
 126                 stk1160_info("Device doesn't support audio, skipping AC97 setup.");
 127                 return;
 128         }
 129
 130         if (!stk1160_has_ac97(dev)) {
 131                 stk1160_info("Device uses internal 8-bit ADC, skipping AC97 setup.");
 132                 return;
 133         }
 134
 135         /* Two-step reset AC97 interface and hardware codec */
 136         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x94);
 137         stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c);
 138
 139         /* Set 16-bit audio data and choose L&R channel*/
 140         stk1160_write_reg(dev, STK1160_AC97CTL_1 + 2, 0x01);
 141         stk1160_write_reg(dev, STK1160_AC97CTL_1 + 3, 0x00);
 142
 143         /* Setup channels */
 144         stk1160_write_ac97(dev, 0x12, 0x8808); /* CD volume */
 145         stk1160_write_ac97(dev, 0x10, 0x0808); /* Line-in volume */
 146         stk1160_write_ac97(dev, 0x0e, 0x0008); /* MIC volume (mono) */
 147         stk1160_write_ac97(dev, 0x16, 0x0808); /* Aux volume */
 148         stk1160_write_ac97(dev, 0x1a, 0x0404); /* Record select */
 149         stk1160_write_ac97(dev, 0x02, 0x0000); /* Master volume */
 150         stk1160_write_ac97(dev, 0x1c, 0x0808); /* Record gain */
 151
 152 #ifdef DEBUG
 153         stk1160_ac97_dump_regs(dev);
 154 #endif
 155 }