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/* SPDX-License-Identifier: GPL-2.0-only */
#include <console/console.h>
#include <device/azalia_device.h>
#include <device/mmio.h>
#include "hda_verb.h"
int hda_codec_detect(u8 *base)
{
u8 reg8;
/* Set Bit 0 to 1 to exit reset state (BAR + 0x8)[0] */
if (azalia_exit_reset(base) < 0)
goto no_codec;
/* Write back the value once reset bit is set. */
write16(base + HDA_GCAP_REG, read16(base + HDA_GCAP_REG));
/*
* Clear the "State Change Status Register" STATESTS bits
* for each of the "SDIN Stat Change Status Flag"
*/
write8(base + HDA_STATESTS_REG, 0xf);
/* Turn off the link and poll RESET# bit until it reads back as 0 */
if (azalia_enter_reset(base) < 0)
goto no_codec;
/* Turn on the link and poll RESET# bit until it reads back as 1 */
if (azalia_exit_reset(base) < 0)
goto no_codec;
/* Read in Codec location (BAR + 0xe)[2..0] */
reg8 = read8(base + HDA_STATESTS_REG);
reg8 &= 0x0f;
if (!reg8)
goto no_codec;
return reg8;
no_codec:
/* Codec not found, put HDA back in reset */
azalia_enter_reset(base);
printk(BIOS_DEBUG, "HDA: No codec!\n");
return 0;
}
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