^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /* MDIO bus multiplexer using kernel multiplexer subsystem
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright 2019 NXP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/mdio-mux.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/mux/consumer.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) struct mdio_mux_multiplexer_state {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) struct mux_control *muxc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) bool do_deselect;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) void *mux_handle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * mdio_mux_multiplexer_switch_fn - This function is called by the mdio-mux
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * layer when it thinks the mdio bus
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * multiplexer needs to switch.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * @current_child: current value of the mux register.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * @desired_child: value of the 'reg' property of the target child MDIO node.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * @data: Private data used by this switch_fn passed to mdio_mux_init function
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * via mdio_mux_init(.., .., .., .., data, ..).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * The first time this function is called, current_child == -1.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * If current_child == desired_child, then the mux is already set to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * correct bus.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) static int mdio_mux_multiplexer_switch_fn(int current_child, int desired_child,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) struct platform_device *pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) struct mdio_mux_multiplexer_state *s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) pdev = (struct platform_device *)data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) s = platform_get_drvdata(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) if (!(current_child ^ desired_child))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) if (s->do_deselect)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) ret = mux_control_deselect(s->muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) dev_err(&pdev->dev, "mux_control_deselect failed in %s: %d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) __func__, ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) ret = mux_control_select(s->muxc, desired_child);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (!ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) dev_dbg(&pdev->dev, "%s %d -> %d\n", __func__, current_child,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) desired_child);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) s->do_deselect = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) s->do_deselect = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static int mdio_mux_multiplexer_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) struct mdio_mux_multiplexer_state *s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) if (!s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) s->muxc = devm_mux_control_get(dev, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) if (IS_ERR(s->muxc)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) ret = PTR_ERR(s->muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) if (ret != -EPROBE_DEFER)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) dev_err(&pdev->dev, "Failed to get mux: %d\n", ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) platform_set_drvdata(pdev, s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) ret = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) mdio_mux_multiplexer_switch_fn, &s->mux_handle,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) pdev, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) static int mdio_mux_multiplexer_remove(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) struct mdio_mux_multiplexer_state *s = platform_get_drvdata(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) mdio_mux_uninit(s->mux_handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) if (s->do_deselect)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) mux_control_deselect(s->muxc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) static const struct of_device_id mdio_mux_multiplexer_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) { .compatible = "mdio-mux-multiplexer", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) {},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) MODULE_DEVICE_TABLE(of, mdio_mux_multiplexer_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) static struct platform_driver mdio_mux_multiplexer_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) .name = "mdio-mux-multiplexer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) .of_match_table = mdio_mux_multiplexer_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) .probe = mdio_mux_multiplexer_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) .remove = mdio_mux_multiplexer_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) module_platform_driver(mdio_mux_multiplexer_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) MODULE_DESCRIPTION("MDIO bus multiplexer using kernel multiplexer subsystem");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) MODULE_AUTHOR("Pankaj Bansal <pankaj.bansal@nxp.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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