xref: /linux/drivers/hwmon/powerz.c (revision 3bf3e21c15d4386a5f15118ec39bbc1b67ea5759)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2023 Thomas Weißschuh <linux@weissschuh.net>
4  */
5 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
6 
7 #include <linux/completion.h>
8 #include <linux/device.h>
9 #include <linux/hwmon.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/types.h>
13 #include <linux/usb.h>
14 
15 #define DRIVER_NAME	"powerz"
16 #define POWERZ_EP_CMD_OUT	0x01
17 #define POWERZ_EP_DATA_IN	0x81
18 
19 struct powerz_sensor_data {
20 	u8 _unknown_1[8];
21 	__le32 V_bus;
22 	__le32 I_bus;
23 	__le32 V_bus_avg;
24 	__le32 I_bus_avg;
25 	u8 _unknown_2[8];
26 	u8 temp[2];
27 	__le16 V_cc1;
28 	__le16 V_cc2;
29 	__le16 V_dp;
30 	__le16 V_dm;
31 	__le16 V_dd;
32 	u8 _unknown_3[4];
33 } __packed;
34 
35 struct powerz_priv {
36 	char transfer_buffer[64];	/* first member to satisfy DMA alignment */
37 	struct mutex mutex;
38 	struct completion completion;
39 	struct urb *urb;
40 	int status;
41 };
42 
43 static const struct hwmon_channel_info *const powerz_info[] = {
44 	HWMON_CHANNEL_INFO(in,
45 			   HWMON_I_INPUT | HWMON_I_LABEL | HWMON_I_AVERAGE,
46 			   HWMON_I_INPUT | HWMON_I_LABEL,
47 			   HWMON_I_INPUT | HWMON_I_LABEL,
48 			   HWMON_I_INPUT | HWMON_I_LABEL,
49 			   HWMON_I_INPUT | HWMON_I_LABEL,
50 			   HWMON_I_INPUT | HWMON_I_LABEL),
51 	HWMON_CHANNEL_INFO(curr,
52 			   HWMON_C_INPUT | HWMON_C_LABEL | HWMON_C_AVERAGE),
53 	    HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_LABEL),
54 	NULL
55 };
56 
57 static umode_t powerz_is_visible(const void *data, enum hwmon_sensor_types type,
58 				 u32 attr, int channel)
59 {
60 	return 0444;
61 }
62 
63 static int powerz_read_string(struct device *dev, enum hwmon_sensor_types type,
64 			      u32 attr, int channel, const char **str)
65 {
66 	if (type == hwmon_curr && attr == hwmon_curr_label) {
67 		*str = "IBUS";
68 	} else if (type == hwmon_in && attr == hwmon_in_label) {
69 		if (channel == 0)
70 			*str = "VBUS";
71 		else if (channel == 1)
72 			*str = "VCC1";
73 		else if (channel == 2)
74 			*str = "VCC2";
75 		else if (channel == 3)
76 			*str = "VDP";
77 		else if (channel == 4)
78 			*str = "VDM";
79 		else if (channel == 5)
80 			*str = "VDD";
81 		else
82 			return -EOPNOTSUPP;
83 	} else if (type == hwmon_temp && attr == hwmon_temp_label) {
84 		*str = "TEMP";
85 	} else {
86 		return -EOPNOTSUPP;
87 	}
88 
89 	return 0;
90 }
91 
92 static void powerz_usb_data_complete(struct urb *urb)
93 {
94 	struct powerz_priv *priv = urb->context;
95 
96 	complete(&priv->completion);
97 }
98 
99 static void powerz_usb_cmd_complete(struct urb *urb)
100 {
101 	struct powerz_priv *priv = urb->context;
102 
103 	usb_fill_bulk_urb(urb, urb->dev,
104 			  usb_rcvbulkpipe(urb->dev, POWERZ_EP_DATA_IN),
105 			  priv->transfer_buffer, sizeof(priv->transfer_buffer),
106 			  powerz_usb_data_complete, priv);
107 
108 	priv->status = usb_submit_urb(urb, GFP_ATOMIC);
109 	if (priv->status)
110 		complete(&priv->completion);
111 }
112 
113 static int powerz_read_data(struct usb_device *udev, struct powerz_priv *priv)
114 {
115 	int ret;
116 
117 	priv->status = -ETIMEDOUT;
118 	reinit_completion(&priv->completion);
119 
120 	priv->transfer_buffer[0] = 0x0c;
121 	priv->transfer_buffer[1] = 0x00;
122 	priv->transfer_buffer[2] = 0x02;
123 	priv->transfer_buffer[3] = 0x00;
124 
125 	usb_fill_bulk_urb(priv->urb, udev,
126 			  usb_sndbulkpipe(udev, POWERZ_EP_CMD_OUT),
127 			  priv->transfer_buffer, 4, powerz_usb_cmd_complete,
128 			  priv);
129 	ret = usb_submit_urb(priv->urb, GFP_KERNEL);
130 	if (ret)
131 		return ret;
132 
133 	if (!wait_for_completion_interruptible_timeout
134 	    (&priv->completion, msecs_to_jiffies(5))) {
135 		usb_kill_urb(priv->urb);
136 		return -EIO;
137 	}
138 
139 	if (priv->urb->actual_length < sizeof(struct powerz_sensor_data))
140 		return -EIO;
141 
142 	return priv->status;
143 }
144 
145 static int powerz_read(struct device *dev, enum hwmon_sensor_types type,
146 		       u32 attr, int channel, long *val)
147 {
148 	struct usb_interface *intf = to_usb_interface(dev->parent);
149 	struct usb_device *udev = interface_to_usbdev(intf);
150 	struct powerz_priv *priv = usb_get_intfdata(intf);
151 	struct powerz_sensor_data *data;
152 	int ret;
153 
154 	if (!priv)
155 		return -EIO;	/* disconnected */
156 
157 	mutex_lock(&priv->mutex);
158 	ret = powerz_read_data(udev, priv);
159 	if (ret)
160 		goto out;
161 
162 	data = (struct powerz_sensor_data *)priv->transfer_buffer;
163 
164 	if (type == hwmon_curr) {
165 		if (attr == hwmon_curr_input)
166 			*val = ((s32)le32_to_cpu(data->I_bus)) / 1000;
167 		else if (attr == hwmon_curr_average)
168 			*val = ((s32)le32_to_cpu(data->I_bus_avg)) / 1000;
169 		else
170 			ret = -EOPNOTSUPP;
171 	} else if (type == hwmon_in) {
172 		if (attr == hwmon_in_input) {
173 			if (channel == 0)
174 				*val = le32_to_cpu(data->V_bus) / 1000;
175 			else if (channel == 1)
176 				*val = le16_to_cpu(data->V_cc1) / 10;
177 			else if (channel == 2)
178 				*val = le16_to_cpu(data->V_cc2) / 10;
179 			else if (channel == 3)
180 				*val = le16_to_cpu(data->V_dp) / 10;
181 			else if (channel == 4)
182 				*val = le16_to_cpu(data->V_dm) / 10;
183 			else if (channel == 5)
184 				*val = le16_to_cpu(data->V_dd) / 10;
185 			else
186 				ret = -EOPNOTSUPP;
187 		} else if (attr == hwmon_in_average && channel == 0) {
188 			*val = le32_to_cpu(data->V_bus_avg) / 1000;
189 		} else {
190 			ret = -EOPNOTSUPP;
191 		}
192 	} else if (type == hwmon_temp && attr == hwmon_temp_input) {
193 		*val = data->temp[1] * 2000 + data->temp[0] * 1000 / 128;
194 	} else {
195 		ret = -EOPNOTSUPP;
196 	}
197 
198 out:
199 	mutex_unlock(&priv->mutex);
200 	return ret;
201 }
202 
203 static const struct hwmon_ops powerz_hwmon_ops = {
204 	.is_visible = powerz_is_visible,
205 	.read = powerz_read,
206 	.read_string = powerz_read_string,
207 };
208 
209 static const struct hwmon_chip_info powerz_chip_info = {
210 	.ops = &powerz_hwmon_ops,
211 	.info = powerz_info,
212 };
213 
214 static int powerz_probe(struct usb_interface *intf,
215 			const struct usb_device_id *id)
216 {
217 	struct powerz_priv *priv;
218 	struct device *hwmon_dev;
219 	struct device *parent;
220 
221 	parent = &intf->dev;
222 
223 	priv = devm_kzalloc(parent, sizeof(*priv), GFP_KERNEL);
224 	if (!priv)
225 		return -ENOMEM;
226 
227 	priv->urb = usb_alloc_urb(0, GFP_KERNEL);
228 	if (!priv->urb)
229 		return -ENOMEM;
230 	mutex_init(&priv->mutex);
231 	init_completion(&priv->completion);
232 
233 	hwmon_dev =
234 	    devm_hwmon_device_register_with_info(parent, DRIVER_NAME, priv,
235 						 &powerz_chip_info, NULL);
236 	if (IS_ERR(hwmon_dev)) {
237 		usb_free_urb(priv->urb);
238 		return PTR_ERR(hwmon_dev);
239 	}
240 
241 	usb_set_intfdata(intf, priv);
242 
243 	return 0;
244 }
245 
246 static void powerz_disconnect(struct usb_interface *intf)
247 {
248 	struct powerz_priv *priv = usb_get_intfdata(intf);
249 
250 	mutex_lock(&priv->mutex);
251 	usb_kill_urb(priv->urb);
252 	usb_free_urb(priv->urb);
253 	mutex_unlock(&priv->mutex);
254 }
255 
256 static const struct usb_device_id powerz_id_table[] = {
257 	{ USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0061, 0x00) },	/* ChargerLAB POWER-Z KM002C */
258 	{ USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0063, 0x00) },	/* ChargerLAB POWER-Z KM003C */
259 	{ }
260 };
261 
262 MODULE_DEVICE_TABLE(usb, powerz_id_table);
263 
264 static struct usb_driver powerz_driver = {
265 	.name = DRIVER_NAME,
266 	.id_table = powerz_id_table,
267 	.probe = powerz_probe,
268 	.disconnect = powerz_disconnect,
269 };
270 
271 module_usb_driver(powerz_driver);
272 
273 MODULE_LICENSE("GPL");
274 MODULE_AUTHOR("Thomas Weißschuh <linux@weissschuh.net>");
275 MODULE_DESCRIPTION("ChargerLAB POWER-Z USB-C tester");
276