// SPDX-License-Identifier: GPL-2.0 /* * Cirrus Logic CS42448/CS42888 Audio CODEC DAI SPI driver * * Copyright 2026 NXP * */ #include #include #include #include #include #include "cs42xx8.h" /* * CS42448/CS42888 SPI register access (from datasheet Figure 23): * * The SPI frame is 3 bytes: * Byte 0: chip address [7:1] = 1001111, bit[0] = R/W (0=write, 1=read) * Write: 0x9E, Read: 0x9F * Byte 1: MAP - Memory Address Pointer * bit[7] = INCR (auto-increment for burst), bits[6:0] = address * Byte 2: data byte * * We configure reg_bits=16 so that regmap treats the address field as 2 bytes * (big-endian). The chip address byte (0x9E/0x9F) is placed in the high byte * via write_flag_mask / read_flag_mask, and the MAP register address occupies * the low byte. Currently INCR (MAP bit[7]) is not set and use_single_read/write * are enabled. This produces the correct 3-byte on-wire frame without any * custom bus implementation: * * write: [0x9E, MAP_addr, data] * read: [0x9F, MAP_addr] -> [data] */ static int cs42xx8_spi_probe(struct spi_device *spi) { struct cs42xx8_driver_data *drvdata; struct regmap_config config; int ret; drvdata = (struct cs42xx8_driver_data *)spi_get_device_match_data(spi); if (!drvdata) return dev_err_probe(&spi->dev, -EINVAL, "failed to find driver data\n"); config = cs42xx8_regmap_config; /* * reg_bits=16 makes regmap send a 2-byte address field (big-endian). * write_flag_mask/read_flag_mask are OR'd into that address field: */ config.reg_bits = 16; config.write_flag_mask = 0x9E; config.read_flag_mask = 0x9F; ret = cs42xx8_probe(&spi->dev, devm_regmap_init_spi(spi, &config), drvdata); if (ret) return ret; pm_runtime_enable(&spi->dev); pm_request_idle(&spi->dev); return 0; } static void cs42xx8_spi_remove(struct spi_device *spi) { pm_runtime_disable(&spi->dev); } static const struct of_device_id cs42xx8_of_match[] = { { .compatible = "cirrus,cs42448", .data = &cs42448_data, }, { .compatible = "cirrus,cs42888", .data = &cs42888_data, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, cs42xx8_of_match); static const struct spi_device_id cs42xx8_spi_id[] = { { .name = "cs42448", .driver_data = (kernel_ulong_t)&cs42448_data }, { .name = "cs42888", .driver_data = (kernel_ulong_t)&cs42888_data }, { } }; MODULE_DEVICE_TABLE(spi, cs42xx8_spi_id); static struct spi_driver cs42xx8_spi_driver = { .driver = { .name = "cs42xx8", .pm = pm_ptr(&cs42xx8_pm), .of_match_table = cs42xx8_of_match, }, .probe = cs42xx8_spi_probe, .remove = cs42xx8_spi_remove, .id_table = cs42xx8_spi_id, }; module_spi_driver(cs42xx8_spi_driver); MODULE_DESCRIPTION("Cirrus Logic CS42448/CS42888 ALSA SoC Codec SPI Driver"); MODULE_AUTHOR("Chancel Liu "); MODULE_LICENSE("GPL");