^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2006 Juergen Beisert, Pengutronix
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2009 Wolfram Sang, Pengutronix
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Check max730x.c for further details.
^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/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/spi/spi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/spi/max7301.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) /* A write to the MAX7301 means one message with one transfer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static int max7301_spi_write(struct device *dev, unsigned int reg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) unsigned int val)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) struct spi_device *spi = to_spi_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) u16 word = ((reg & 0x7F) << 8) | (val & 0xFF);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) return spi_write_then_read(spi, &word, sizeof(word), NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) /* A read from the MAX7301 means two transfers; here, one message each */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) static int max7301_spi_read(struct device *dev, unsigned int reg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) u16 word;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) struct spi_device *spi = to_spi_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) word = 0x8000 | (reg << 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) ret = spi_write_then_read(spi, &word, sizeof(word), &word,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) sizeof(word));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) return word & 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) static int max7301_probe(struct spi_device *spi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) struct max7301 *ts;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) /* bits_per_word cannot be configured in platform data */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) spi->bits_per_word = 16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) ret = spi_setup(spi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) ts = devm_kzalloc(&spi->dev, sizeof(struct max7301), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) if (!ts)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) ts->read = max7301_spi_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) ts->write = max7301_spi_write;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) ts->dev = &spi->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) ret = __max730x_probe(ts);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static int max7301_remove(struct spi_device *spi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) return __max730x_remove(&spi->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) static const struct spi_device_id max7301_id[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) { "max7301", 0 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) MODULE_DEVICE_TABLE(spi, max7301_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) static struct spi_driver max7301_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) .name = "max7301",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) .probe = max7301_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) .remove = max7301_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) .id_table = max7301_id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) static int __init max7301_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) return spi_register_driver(&max7301_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) /* register after spi postcore initcall and before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) * subsys initcalls that may rely on these GPIOs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) subsys_initcall(max7301_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static void __exit max7301_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) spi_unregister_driver(&max7301_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) module_exit(max7301_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) MODULE_LICENSE("GPL v2");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) MODULE_DESCRIPTION("MAX7301 GPIO-Expander");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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