1 // SPDX-License-Identifier: GPL-2.0
3 * phy-can-transceiver.c - phy driver for CAN transceivers
5 * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com
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>
14 struct can_transceiver_data
{
16 #define CAN_TRANSCEIVER_STB_PRESENT BIT(0)
17 #define CAN_TRANSCEIVER_EN_PRESENT BIT(1)
20 struct can_transceiver_phy
{
21 struct phy
*generic_phy
;
22 struct gpio_desc
*standby_gpio
;
23 struct gpio_desc
*enable_gpio
;
26 /* Power on function */
27 static int can_transceiver_phy_power_on(struct phy
*phy
)
29 struct can_transceiver_phy
*can_transceiver_phy
= phy_get_drvdata(phy
);
31 if (can_transceiver_phy
->standby_gpio
)
32 gpiod_set_value_cansleep(can_transceiver_phy
->standby_gpio
, 0);
33 if (can_transceiver_phy
->enable_gpio
)
34 gpiod_set_value_cansleep(can_transceiver_phy
->enable_gpio
, 1);
39 /* Power off function */
40 static int can_transceiver_phy_power_off(struct phy
*phy
)
42 struct can_transceiver_phy
*can_transceiver_phy
= phy_get_drvdata(phy
);
44 if (can_transceiver_phy
->standby_gpio
)
45 gpiod_set_value_cansleep(can_transceiver_phy
->standby_gpio
, 1);
46 if (can_transceiver_phy
->enable_gpio
)
47 gpiod_set_value_cansleep(can_transceiver_phy
->enable_gpio
, 0);
52 static const struct phy_ops can_transceiver_phy_ops
= {
53 .power_on
= can_transceiver_phy_power_on
,
54 .power_off
= can_transceiver_phy_power_off
,
58 static const struct can_transceiver_data tcan1042_drvdata
= {
59 .flags
= CAN_TRANSCEIVER_STB_PRESENT
,
62 static const struct can_transceiver_data tcan1043_drvdata
= {
63 .flags
= CAN_TRANSCEIVER_STB_PRESENT
| CAN_TRANSCEIVER_EN_PRESENT
,
66 static const struct of_device_id can_transceiver_phy_ids
[] = {
68 .compatible
= "ti,tcan1042",
69 .data
= &tcan1042_drvdata
72 .compatible
= "ti,tcan1043",
73 .data
= &tcan1043_drvdata
77 MODULE_DEVICE_TABLE(of
, can_transceiver_phy_ids
);
79 static int can_transceiver_phy_probe(struct platform_device
*pdev
)
81 struct phy_provider
*phy_provider
;
82 struct device
*dev
= &pdev
->dev
;
83 struct can_transceiver_phy
*can_transceiver_phy
;
84 const struct can_transceiver_data
*drvdata
;
85 const struct of_device_id
*match
;
87 struct gpio_desc
*standby_gpio
;
88 struct gpio_desc
*enable_gpio
;
91 can_transceiver_phy
= devm_kzalloc(dev
, sizeof(struct can_transceiver_phy
), GFP_KERNEL
);
92 if (!can_transceiver_phy
)
95 match
= of_match_node(can_transceiver_phy_ids
, pdev
->dev
.of_node
);
96 drvdata
= match
->data
;
98 phy
= devm_phy_create(dev
, dev
->of_node
,
99 &can_transceiver_phy_ops
);
101 dev_err(dev
, "failed to create can transceiver phy\n");
105 device_property_read_u32(dev
, "max-bitrate", &max_bitrate
);
107 dev_warn(dev
, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n");
108 phy
->attrs
.max_link_rate
= max_bitrate
;
110 can_transceiver_phy
->generic_phy
= phy
;
112 if (drvdata
->flags
& CAN_TRANSCEIVER_STB_PRESENT
) {
113 standby_gpio
= devm_gpiod_get(dev
, "standby", GPIOD_OUT_HIGH
);
114 if (IS_ERR(standby_gpio
))
115 return PTR_ERR(standby_gpio
);
116 can_transceiver_phy
->standby_gpio
= standby_gpio
;
119 if (drvdata
->flags
& CAN_TRANSCEIVER_EN_PRESENT
) {
120 enable_gpio
= devm_gpiod_get(dev
, "enable", GPIOD_OUT_LOW
);
121 if (IS_ERR(enable_gpio
))
122 return PTR_ERR(enable_gpio
);
123 can_transceiver_phy
->enable_gpio
= enable_gpio
;
126 phy_set_drvdata(can_transceiver_phy
->generic_phy
, can_transceiver_phy
);
128 phy_provider
= devm_of_phy_provider_register(dev
, of_phy_simple_xlate
);
130 return PTR_ERR_OR_ZERO(phy_provider
);
133 static struct platform_driver can_transceiver_phy_driver
= {
134 .probe
= can_transceiver_phy_probe
,
136 .name
= "can-transceiver-phy",
137 .of_match_table
= can_transceiver_phy_ids
,
141 module_platform_driver(can_transceiver_phy_driver
);
143 MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>");
144 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
145 MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver");
146 MODULE_LICENSE("GPL v2");