WSL2-Linux-Kernel/drivers/phy/phy-can-transceiver.c

147 строки
4.1 KiB
C

// 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>
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;
};
/* Power on function */
static int can_transceiver_phy_power_on(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, 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);
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;
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;
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);
}
device_property_read_u32(dev, "max-bitrate", &max_bitrate);
if (!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");