^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) * General Purpose I2C multiplexer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2017 Axentia Technologies AB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Author: Peter Rosin <peda@axentia.se>
^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/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/i2c-mux.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/mux/consumer.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/of_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) struct mux {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) struct mux_control *control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) bool do_not_deselect;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) static int i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) struct mux *mux = i2c_mux_priv(muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) ret = mux_control_select(mux->control, chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) mux->do_not_deselect = ret < 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) static int i2c_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) struct mux *mux = i2c_mux_priv(muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) if (mux->do_not_deselect)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) return mux_control_deselect(mux->control);
^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 struct i2c_adapter *mux_parent_adapter(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) struct device_node *np = dev->of_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) struct device_node *parent_np;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) struct i2c_adapter *parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) parent_np = of_parse_phandle(np, "i2c-parent", 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) if (!parent_np) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) dev_err(dev, "Cannot parse i2c-parent\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) return ERR_PTR(-ENODEV);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) parent = of_find_i2c_adapter_by_node(parent_np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) of_node_put(parent_np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) if (!parent)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) return ERR_PTR(-EPROBE_DEFER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) return parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) static const struct of_device_id i2c_mux_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) { .compatible = "i2c-mux", },
^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) MODULE_DEVICE_TABLE(of, i2c_mux_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) static int i2c_mux_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) struct device_node *np = dev->of_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) struct device_node *child;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) struct i2c_mux_core *muxc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) struct mux *mux;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) struct i2c_adapter *parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) int children;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) if (!np)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) if (!mux)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) mux->control = devm_mux_control_get(dev, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) if (IS_ERR(mux->control))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) return dev_err_probe(dev, PTR_ERR(mux->control),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) "failed to get control-mux\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) parent = mux_parent_adapter(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (IS_ERR(parent))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) return dev_err_probe(dev, PTR_ERR(parent),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) "failed to get i2c-parent adapter\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) children = of_get_child_count(np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) muxc = i2c_mux_alloc(parent, dev, children, 0, 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) i2c_mux_select, i2c_mux_deselect);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) if (!muxc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) goto err_parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) muxc->priv = mux;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) platform_set_drvdata(pdev, muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) muxc->mux_locked = of_property_read_bool(np, "mux-locked");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) for_each_child_of_node(np, child) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) u32 chan;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) ret = of_property_read_u32(child, "reg", &chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) if (ret < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) dev_err(dev, "no reg property for node '%pOFn'\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) child);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) goto err_children;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) if (chan >= mux_control_states(mux->control)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) dev_err(dev, "invalid reg %u\n", chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) goto err_children;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) ret = i2c_mux_add_adapter(muxc, 0, chan, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) goto err_children;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) dev_info(dev, "%d-port mux on %s adapter\n", children, parent->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) err_children:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) i2c_mux_del_adapters(muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) err_parent:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) i2c_put_adapter(parent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static int i2c_mux_remove(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) i2c_mux_del_adapters(muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) i2c_put_adapter(muxc->parent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) static struct platform_driver i2c_mux_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) .probe = i2c_mux_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) .remove = i2c_mux_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) .name = "i2c-mux-gpmux",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) .of_match_table = i2c_mux_of_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) module_platform_driver(i2c_mux_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) MODULE_DESCRIPTION("General Purpose I2C multiplexer driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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