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1// SPDX-License-Identifier: GPL-2.02/*3 * phy-can-transceiver.c - phy driver for CAN transceivers4 *5 * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com6 *7 */8#include <linux/of.h>9#include <linux/phy/phy.h>10#include <linux/platform_device.h>11#include <linux/module.h>12#include <linux/gpio.h>13#include <linux/gpio/consumer.h>14#include <linux/mux/consumer.h>15 16struct can_transceiver_data {17 u32 flags;18#define CAN_TRANSCEIVER_STB_PRESENT BIT(0)19#define CAN_TRANSCEIVER_EN_PRESENT BIT(1)20};21 22struct can_transceiver_phy {23 struct phy *generic_phy;24 struct gpio_desc *standby_gpio;25 struct gpio_desc *enable_gpio;26 struct mux_state *mux_state;27};28 29/* Power on function */30static int can_transceiver_phy_power_on(struct phy *phy)31{32 struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);33 int ret;34 35 if (can_transceiver_phy->mux_state) {36 ret = mux_state_select(can_transceiver_phy->mux_state);37 if (ret) {38 dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret);39 return ret;40 }41 }42 if (can_transceiver_phy->standby_gpio)43 gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0);44 if (can_transceiver_phy->enable_gpio)45 gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1);46 47 return 0;48}49 50/* Power off function */51static int can_transceiver_phy_power_off(struct phy *phy)52{53 struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);54 55 if (can_transceiver_phy->standby_gpio)56 gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1);57 if (can_transceiver_phy->enable_gpio)58 gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0);59 if (can_transceiver_phy->mux_state)60 mux_state_deselect(can_transceiver_phy->mux_state);61 62 return 0;63}64 65static const struct phy_ops can_transceiver_phy_ops = {66 .power_on = can_transceiver_phy_power_on,67 .power_off = can_transceiver_phy_power_off,68 .owner = THIS_MODULE,69};70 71static const struct can_transceiver_data tcan1042_drvdata = {72 .flags = CAN_TRANSCEIVER_STB_PRESENT,73};74 75static const struct can_transceiver_data tcan1043_drvdata = {76 .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT,77};78 79static const struct of_device_id can_transceiver_phy_ids[] = {80 {81 .compatible = "ti,tcan1042",82 .data = &tcan1042_drvdata83 },84 {85 .compatible = "ti,tcan1043",86 .data = &tcan1043_drvdata87 },88 {89 .compatible = "nxp,tjr1443",90 .data = &tcan1043_drvdata91 },92 { }93};94MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids);95 96static int can_transceiver_phy_probe(struct platform_device *pdev)97{98 struct phy_provider *phy_provider;99 struct device *dev = &pdev->dev;100 struct can_transceiver_phy *can_transceiver_phy;101 const struct can_transceiver_data *drvdata;102 const struct of_device_id *match;103 struct phy *phy;104 struct gpio_desc *standby_gpio;105 struct gpio_desc *enable_gpio;106 u32 max_bitrate = 0;107 int err;108 109 can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL);110 if (!can_transceiver_phy)111 return -ENOMEM;112 113 match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node);114 drvdata = match->data;115 116 if (of_property_read_bool(dev->of_node, "mux-states")) {117 struct mux_state *mux_state;118 119 mux_state = devm_mux_state_get(dev, NULL);120 if (IS_ERR(mux_state))121 return dev_err_probe(&pdev->dev, PTR_ERR(mux_state),122 "failed to get mux\n");123 can_transceiver_phy->mux_state = mux_state;124 }125 126 phy = devm_phy_create(dev, dev->of_node,127 &can_transceiver_phy_ops);128 if (IS_ERR(phy)) {129 dev_err(dev, "failed to create can transceiver phy\n");130 return PTR_ERR(phy);131 }132 133 err = device_property_read_u32(dev, "max-bitrate", &max_bitrate);134 if ((err != -EINVAL) && !max_bitrate)135 dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n");136 phy->attrs.max_link_rate = max_bitrate;137 138 can_transceiver_phy->generic_phy = phy;139 140 if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) {141 standby_gpio = devm_gpiod_get_optional(dev, "standby", GPIOD_OUT_HIGH);142 if (IS_ERR(standby_gpio))143 return PTR_ERR(standby_gpio);144 can_transceiver_phy->standby_gpio = standby_gpio;145 }146 147 if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) {148 enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);149 if (IS_ERR(enable_gpio))150 return PTR_ERR(enable_gpio);151 can_transceiver_phy->enable_gpio = enable_gpio;152 }153 154 phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy);155 156 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);157 158 return PTR_ERR_OR_ZERO(phy_provider);159}160 161static struct platform_driver can_transceiver_phy_driver = {162 .probe = can_transceiver_phy_probe,163 .driver = {164 .name = "can-transceiver-phy",165 .of_match_table = can_transceiver_phy_ids,166 },167};168 169module_platform_driver(can_transceiver_phy_driver);170 171MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>");172MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");173MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver");174MODULE_LICENSE("GPL v2");175