// SPDX-License-Identifier: GPL-2.0 /* * phy-can-transceiver.c - phy driver for CAN transceivers * * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com * */ #include<linux/phy/phy.h> #include<linux/platform_device.h> #include<linux/module.h> #include<linux/gpio.h> #include<linux/gpio/consumer.h> #include <linux/mux/consumer.h> struct can_transceiver_data { u32 flags; #define CAN_TRANSCEIVER_STB_PRESENT BIT(0) #define CAN_TRANSCEIVER_EN_PRESENT BIT(1) }; struct can_transceiver_phy { struct phy *generic_phy; struct gpio_desc *standby_gpio; struct gpio_desc *enable_gpio; struct mux_state *mux_state; }; /* Power on function */ static int can_transceiver_phy_power_on(struct phy *phy) { struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); int ret; if (can_transceiver_phy->mux_state) { ret = mux_state_select(can_transceiver_phy->mux_state); if (ret) { dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret); return ret; } } if (can_transceiver_phy->standby_gpio) gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0); if (can_transceiver_phy->enable_gpio) gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1); return 0; } /* Power off function */ static int can_transceiver_phy_power_off(struct phy *phy) { struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); if (can_transceiver_phy->standby_gpio) gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1); if (can_transceiver_phy->enable_gpio) gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0); if (can_transceiver_phy->mux_state) mux_state_deselect(can_transceiver_phy->mux_state); return 0; } static const struct phy_ops can_transceiver_phy_ops = { .power_on = can_transceiver_phy_power_on, .power_off = can_transceiver_phy_power_off, .owner = THIS_MODULE, }; static const struct can_transceiver_data tcan1042_drvdata = { .flags = CAN_TRANSCEIVER_STB_PRESENT, }; static const struct can_transceiver_data tcan1043_drvdata = { .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT, }; static const struct of_device_id can_transceiver_phy_ids[] = { { .compatible = "ti,tcan1042", .data = &tcan1042_drvdata }, { .compatible = "ti,tcan1043", .data = &tcan1043_drvdata }, { } }; MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids); static int can_transceiver_phy_probe(struct platform_device *pdev) { struct phy_provider *phy_provider; struct device *dev = &pdev->dev; struct can_transceiver_phy *can_transceiver_phy; const struct can_transceiver_data *drvdata; const struct of_device_id *match; struct phy *phy; struct gpio_desc *standby_gpio; struct gpio_desc *enable_gpio; u32 max_bitrate = 0; int err; can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL); if (!can_transceiver_phy) return -ENOMEM; match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); drvdata = match->data; if (of_property_read_bool(dev->of_node, "mux-states")) { struct mux_state *mux_state; mux_state = devm_mux_state_get(dev, NULL); if (IS_ERR(mux_state)) return dev_err_probe(&pdev->dev, PTR_ERR(mux_state), "failed to get mux\n"); can_transceiver_phy->mux_state = mux_state; } phy = devm_phy_create(dev, dev->of_node, &can_transceiver_phy_ops); if (IS_ERR(phy)) { dev_err(dev, "failed to create can transceiver phy\n"); return PTR_ERR(phy); } err = device_property_read_u32(dev, "max-bitrate", &max_bitrate); if ((err != -EINVAL) && !max_bitrate) dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n"); phy->attrs.max_link_rate = max_bitrate; can_transceiver_phy->generic_phy = phy; if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) { standby_gpio = devm_gpiod_get_optional(dev, "standby", GPIOD_OUT_HIGH); if (IS_ERR(standby_gpio)) return PTR_ERR(standby_gpio); can_transceiver_phy->standby_gpio = standby_gpio; } if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) { enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW); if (IS_ERR(enable_gpio)) return PTR_ERR(enable_gpio); can_transceiver_phy->enable_gpio = enable_gpio; } phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); return PTR_ERR_OR_ZERO(phy_provider); } static struct platform_driver can_transceiver_phy_driver = { .probe = can_transceiver_phy_probe, .driver = { .name = "can-transceiver-phy", .of_match_table = can_transceiver_phy_ids, }, }; module_platform_driver(can_transceiver_phy_driver); MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>"); MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>"); MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver"); MODULE_LICENSE("GPL v2");