^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Linux driver model AC97 bus interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Author: Nicolas Pitre
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Created: Jan 14, 2005
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright: (C) MontaVista Software Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <sound/ac97_codec.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * snd_ac97_check_id() - Reads and checks the vendor ID of the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * @ac97: The AC97 device to check
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * @id: The ID to compare to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * @id_mask: Mask that is applied to the device ID before comparing to @id
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * If @id is 0 this function returns true if the read device vendor ID is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * a valid ID. If @id is non 0 this functions returns true if @id
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * matches the read vendor ID. Otherwise the function returns false.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static bool snd_ac97_check_id(struct snd_ac97 *ac97, unsigned int id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) unsigned int id_mask)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) ac97->id = ac97->bus->ops->read(ac97, AC97_VENDOR_ID1) << 16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) ac97->id |= ac97->bus->ops->read(ac97, AC97_VENDOR_ID2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) if (ac97->id == 0x0 || ac97->id == 0xffffffff)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) if (id != 0 && id != (ac97->id & id_mask))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) * snd_ac97_reset() - Reset AC'97 device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) * @ac97: The AC'97 device to reset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) * @try_warm: Try a warm reset first
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) * @id: Expected device vendor ID
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * @id_mask: Mask that is applied to the device ID before comparing to @id
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * This function resets the AC'97 device. If @try_warm is true the function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * first performs a warm reset. If the warm reset is successful the function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) * returns 1. Otherwise or if @try_warm is false the function issues cold reset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * followed by a warm reset. If this is successful the function returns 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * otherwise a negative error code. If @id is 0 any valid device ID will be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) * accepted, otherwise only the ID that matches @id and @id_mask is accepted.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) unsigned int id_mask)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) const struct snd_ac97_bus_ops *ops = ac97->bus->ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) if (try_warm && ops->warm_reset) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) ops->warm_reset(ac97);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) if (snd_ac97_check_id(ac97, id, id_mask))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) if (ops->reset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) ops->reset(ac97);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) if (ops->warm_reset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) ops->warm_reset(ac97);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) if (snd_ac97_check_id(ac97, id, id_mask))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) EXPORT_SYMBOL_GPL(snd_ac97_reset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) * Let drivers decide whether they want to support given codec from their
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) * probe method. Drivers have direct access to the struct snd_ac97
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) * structure and may decide based on the id field amongst other things.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) static int ac97_bus_match(struct device *dev, struct device_driver *drv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) struct bus_type ac97_bus_type = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) .name = "ac97",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) .match = ac97_bus_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) static int __init ac97_bus_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) return bus_register(&ac97_bus_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) subsys_initcall(ac97_bus_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) static void __exit ac97_bus_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) bus_unregister(&ac97_bus_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) module_exit(ac97_bus_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) EXPORT_SYMBOL(ac97_bus_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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