^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) * 1-Wire implementation for the ds2781 chip
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Author: Renata Sayakhova <renata@oktetlabs.ru>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Based on w1-ds2780 driver
^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/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/module.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/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/w1.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include "w1_ds2781.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #define W1_FAMILY_DS2781 0x3D
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) static int w1_ds2781_do_io(struct device *dev, char *buf, int addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) size_t count, int io)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) if (addr > DS2781_DATA_SIZE || addr < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) count = min_t(int, count, DS2781_DATA_SIZE - addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) if (w1_reset_select_slave(sl) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) if (io) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) w1_write_8(sl->master, W1_DS2781_WRITE_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) w1_write_8(sl->master, addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) w1_write_block(sl->master, buf, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) w1_write_8(sl->master, W1_DS2781_READ_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) w1_write_8(sl->master, addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) count = w1_read_block(sl->master, buf, count);
^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)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) int io)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) if (!dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) mutex_lock(&sl->master->bus_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) ret = w1_ds2781_do_io(dev, buf, addr, count, io);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) mutex_unlock(&sl->master->bus_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) EXPORT_SYMBOL(w1_ds2781_io);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) if (!dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) mutex_lock(&sl->master->bus_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) if (w1_reset_select_slave(sl) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) w1_write_8(sl->master, cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) w1_write_8(sl->master, addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) mutex_unlock(&sl->master->bus_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) EXPORT_SYMBOL(w1_ds2781_eeprom_cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) struct bin_attribute *bin_attr, char *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) loff_t off, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) struct device *dev = container_of(kobj, struct device, kobj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) return w1_ds2781_io(dev, buf, off, count, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) static BIN_ATTR_RO(w1_slave, DS2781_DATA_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static struct bin_attribute *w1_ds2781_bin_attrs[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) &bin_attr_w1_slave,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) static const struct attribute_group w1_ds2781_group = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) .bin_attrs = w1_ds2781_bin_attrs,
^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) static const struct attribute_group *w1_ds2781_groups[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) &w1_ds2781_group,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) static int w1_ds2781_add_slave(struct w1_slave *sl)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) struct platform_device *pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) pdev = platform_device_alloc("ds2781-battery", PLATFORM_DEVID_AUTO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) if (!pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) pdev->dev.parent = &sl->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) ret = platform_device_add(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) goto pdev_add_failed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) dev_set_drvdata(&sl->dev, pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) pdev_add_failed:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) platform_device_put(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) static void w1_ds2781_remove_slave(struct w1_slave *sl)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) struct platform_device *pdev = dev_get_drvdata(&sl->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) platform_device_unregister(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) static const struct w1_family_ops w1_ds2781_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) .add_slave = w1_ds2781_add_slave,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) .remove_slave = w1_ds2781_remove_slave,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) .groups = w1_ds2781_groups,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) static struct w1_family w1_ds2781_family = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) .fid = W1_FAMILY_DS2781,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) .fops = &w1_ds2781_fops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) module_w1_family(w1_ds2781_family);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2781));