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/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 | |
16 | struct can_transceiver_data { |
17 | u32 flags; |
18 | #define CAN_TRANSCEIVER_STB_PRESENT BIT(0) |
19 | #define CAN_TRANSCEIVER_EN_PRESENT BIT(1) |
20 | }; |
21 | |
22 | struct 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 */ |
30 | static 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(mstate: 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(desc: can_transceiver_phy->standby_gpio, value: 0); |
44 | if (can_transceiver_phy->enable_gpio) |
45 | gpiod_set_value_cansleep(desc: can_transceiver_phy->enable_gpio, value: 1); |
46 | |
47 | return 0; |
48 | } |
49 | |
50 | /* Power off function */ |
51 | static 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(desc: can_transceiver_phy->standby_gpio, value: 1); |
57 | if (can_transceiver_phy->enable_gpio) |
58 | gpiod_set_value_cansleep(desc: can_transceiver_phy->enable_gpio, value: 0); |
59 | if (can_transceiver_phy->mux_state) |
60 | mux_state_deselect(mstate: can_transceiver_phy->mux_state); |
61 | |
62 | return 0; |
63 | } |
64 | |
65 | static 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 | |
71 | static const struct can_transceiver_data tcan1042_drvdata = { |
72 | .flags = CAN_TRANSCEIVER_STB_PRESENT, |
73 | }; |
74 | |
75 | static const struct can_transceiver_data tcan1043_drvdata = { |
76 | .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT, |
77 | }; |
78 | |
79 | static const struct of_device_id can_transceiver_phy_ids[] = { |
80 | { |
81 | .compatible = "ti,tcan1042" , |
82 | .data = &tcan1042_drvdata |
83 | }, |
84 | { |
85 | .compatible = "ti,tcan1043" , |
86 | .data = &tcan1043_drvdata |
87 | }, |
88 | { |
89 | .compatible = "nxp,tjr1443" , |
90 | .data = &tcan1043_drvdata |
91 | }, |
92 | { } |
93 | }; |
94 | MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids); |
95 | |
96 | static 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, size: sizeof(struct can_transceiver_phy), GFP_KERNEL); |
110 | if (!can_transceiver_phy) |
111 | return -ENOMEM; |
112 | |
113 | match = of_match_node(matches: can_transceiver_phy_ids, node: pdev->dev.of_node); |
114 | drvdata = match->data; |
115 | |
116 | if (of_property_read_bool(np: dev->of_node, propname: "mux-states" )) { |
117 | struct mux_state *mux_state; |
118 | |
119 | mux_state = devm_mux_state_get(dev, NULL); |
120 | if (IS_ERR(ptr: mux_state)) |
121 | return dev_err_probe(dev: &pdev->dev, err: PTR_ERR(ptr: mux_state), |
122 | fmt: "failed to get mux\n" ); |
123 | can_transceiver_phy->mux_state = mux_state; |
124 | } |
125 | |
126 | phy = devm_phy_create(dev, node: dev->of_node, |
127 | ops: &can_transceiver_phy_ops); |
128 | if (IS_ERR(ptr: phy)) { |
129 | dev_err(dev, "failed to create can transceiver phy\n" ); |
130 | return PTR_ERR(ptr: phy); |
131 | } |
132 | |
133 | err = device_property_read_u32(dev, propname: "max-bitrate" , val: &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, con_id: "standby" , flags: GPIOD_OUT_HIGH); |
142 | if (IS_ERR(ptr: standby_gpio)) |
143 | return PTR_ERR(ptr: 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, con_id: "enable" , flags: GPIOD_OUT_LOW); |
149 | if (IS_ERR(ptr: enable_gpio)) |
150 | return PTR_ERR(ptr: enable_gpio); |
151 | can_transceiver_phy->enable_gpio = enable_gpio; |
152 | } |
153 | |
154 | phy_set_drvdata(phy: can_transceiver_phy->generic_phy, data: can_transceiver_phy); |
155 | |
156 | phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); |
157 | |
158 | return PTR_ERR_OR_ZERO(ptr: phy_provider); |
159 | } |
160 | |
161 | static 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 | |
169 | module_platform_driver(can_transceiver_phy_driver); |
170 | |
171 | MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>" ); |
172 | MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>" ); |
173 | MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver" ); |
174 | MODULE_LICENSE("GPL v2" ); |
175 | |