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-rw-r--r--drivers/phy/phy-can-transceiver.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c
new file mode 100644
index 000000000..ce511ad5d
--- /dev/null
+++ b/drivers/phy/phy-can-transceiver.c
@@ -0,0 +1,169 @@
+// 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");