[linux-block.git] / drivers / phy / phy-can-transceiver.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>
#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");
Commit	Line	Data
a4a86d27 AG	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* phy-can-transceiver.c - phy driver for CAN transceivers
	4	*
	5	* Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com
	6	*
	7	*/
	8	#include<linux/phy/phy.h>
	9	#include<linux/platform_device.h>
	10	#include<linux/module.h>
	11	#include<linux/gpio.h>
	12	#include<linux/gpio/consumer.h>
e4d43712	13	#include <linux/mux/consumer.h>
a4a86d27 AG	14
	15	struct can_transceiver_data {
	16	u32 flags;
	17	#define CAN_TRANSCEIVER_STB_PRESENT BIT(0)
	18	#define CAN_TRANSCEIVER_EN_PRESENT BIT(1)
	19	};
	20
	21	struct can_transceiver_phy {
	22	struct phy *generic_phy;
	23	struct gpio_desc *standby_gpio;
	24	struct gpio_desc *enable_gpio;
e4d43712	25	struct mux_state *mux_state;
a4a86d27 AG	26	};
	27
	28	/* Power on function */
	29	static int can_transceiver_phy_power_on(struct phy *phy)
	30	{
	31	struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
e4d43712 AG	32	int ret;
	33
	34	if (can_transceiver_phy->mux_state) {
	35	ret = mux_state_select(can_transceiver_phy->mux_state);
	36	if (ret) {
	37	dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret);
	38	return ret;
	39	}
	40	}
a4a86d27 AG	41	if (can_transceiver_phy->standby_gpio)
	42	gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0);
	43	if (can_transceiver_phy->enable_gpio)
	44	gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1);
	45
	46	return 0;
	47	}
	48
	49	/* Power off function */
	50	static int can_transceiver_phy_power_off(struct phy *phy)
	51	{
	52	struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
	53
	54	if (can_transceiver_phy->standby_gpio)
	55	gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1);
	56	if (can_transceiver_phy->enable_gpio)
	57	gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0);
e4d43712 AG	58	if (can_transceiver_phy->mux_state)
e4d43712 AG	59	mux_state_deselect(can_transceiver_phy->mux_state);
a4a86d27 AG	60
	61	return 0;
	62	}
	63
	64	static const struct phy_ops can_transceiver_phy_ops = {
	65	.power_on = can_transceiver_phy_power_on,
	66	.power_off = can_transceiver_phy_power_off,
	67	.owner = THIS_MODULE,
	68	};
	69
	70	static const struct can_transceiver_data tcan1042_drvdata = {
	71	.flags = CAN_TRANSCEIVER_STB_PRESENT,
	72	};
	73
	74	static const struct can_transceiver_data tcan1043_drvdata = {
	75	.flags = CAN_TRANSCEIVER_STB_PRESENT \| CAN_TRANSCEIVER_EN_PRESENT,
	76	};
	77
	78	static const struct of_device_id can_transceiver_phy_ids[] = {
	79	{
	80	.compatible = "ti,tcan1042",
	81	.data = &tcan1042_drvdata
	82	},
	83	{
	84	.compatible = "ti,tcan1043",
	85	.data = &tcan1043_drvdata
	86	},
	87	{ }
	88	};
	89	MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids);
	90
	91	static int can_transceiver_phy_probe(struct platform_device *pdev)
	92	{
	93	struct phy_provider *phy_provider;
	94	struct device *dev = &pdev->dev;
	95	struct can_transceiver_phy *can_transceiver_phy;
	96	const struct can_transceiver_data *drvdata;
	97	const struct of_device_id *match;
	98	struct phy *phy;
	99	struct gpio_desc *standby_gpio;
	100	struct gpio_desc *enable_gpio;
	101	u32 max_bitrate = 0;
bc30c15f	102	int err;
a4a86d27 AG	103
	104	can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL);
	105	if (!can_transceiver_phy)
	106	return -ENOMEM;
	107
	108	match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node);
	109	drvdata = match->data;
	110
e4d43712 AG	111	if (of_property_read_bool(dev->of_node, "mux-states")) {
	112	struct mux_state *mux_state;
	113
	114	mux_state = devm_mux_state_get(dev, NULL);
	115	if (IS_ERR(mux_state))
	116	return dev_err_probe(&pdev->dev, PTR_ERR(mux_state),
	117	"failed to get mux\n");
	118	can_transceiver_phy->mux_state = mux_state;
	119	}
	120
a4a86d27 AG	121	phy = devm_phy_create(dev, dev->of_node,
	122	&can_transceiver_phy_ops);
	123	if (IS_ERR(phy)) {
	124	dev_err(dev, "failed to create can transceiver phy\n");
	125	return PTR_ERR(phy);
	126	}
	127
bc30c15f GU	128	err = device_property_read_u32(dev, "max-bitrate", &max_bitrate);
bc30c15f GU	129	if ((err != -EINVAL) && !max_bitrate)
a4a86d27 AG	130	dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n");
	131	phy->attrs.max_link_rate = max_bitrate;
	132
	133	can_transceiver_phy->generic_phy = phy;
	134
	135	if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) {
be24d248	136	standby_gpio = devm_gpiod_get_optional(dev, "standby", GPIOD_OUT_HIGH);
a4a86d27 AG	137	if (IS_ERR(standby_gpio))
	138	return PTR_ERR(standby_gpio);
	139	can_transceiver_phy->standby_gpio = standby_gpio;
	140	}
	141
	142	if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) {
be24d248	143	enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
a4a86d27 AG	144	if (IS_ERR(enable_gpio))
	145	return PTR_ERR(enable_gpio);
	146	can_transceiver_phy->enable_gpio = enable_gpio;
	147	}
	148
	149	phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy);
	150
	151	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
	152
	153	return PTR_ERR_OR_ZERO(phy_provider);
	154	}
	155
	156	static struct platform_driver can_transceiver_phy_driver = {
	157	.probe = can_transceiver_phy_probe,
	158	.driver = {
	159	.name = "can-transceiver-phy",
	160	.of_match_table = can_transceiver_phy_ids,
	161	},
	162	};
	163
	164	module_platform_driver(can_transceiver_phy_driver);
	165
	166	MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>");
	167	MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
	168	MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver");
	169	MODULE_LICENSE("GPL v2");