xref: /linux/drivers/hwmon/powerz.c (revision 53597deca0e38c30e6cd4ba2114fa42d2bcd85bb)
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/dma-mapping.h>
10 #include <linux/hwmon.h>
11 #include <linux/module.h>
12 #include <linux/mutex.h>
13 #include <linux/types.h>
14 #include <linux/usb.h>
15 
16 #define DRIVER_NAME	"powerz"
17 #define POWERZ_EP_CMD_OUT	0x01
18 #define POWERZ_EP_DATA_IN	0x81
19 
20 struct powerz_sensor_data {
21 	u8 _unknown_1[8];
22 	__le32 V_bus;
23 	__le32 I_bus;
24 	__le32 V_bus_avg;
25 	__le32 I_bus_avg;
26 	u8 _unknown_2[8];
27 	u8 temp[2];
28 	__le16 V_cc1;
29 	__le16 V_cc2;
30 	__le16 V_dp;
31 	__le16 V_dm;
32 	__le16 V_dd;
33 	u8 _unknown_3[4];
34 } __packed;
35 
36 struct powerz_priv {
37 	__dma_from_device_group_begin();
38 	char transfer_buffer[64];
39 	__dma_from_device_group_end();
40 	struct mutex mutex;
41 	struct completion completion;
42 	struct urb *urb;
43 	int status;
44 };
45 
46 static const struct hwmon_channel_info *const powerz_info[] = {
47 	HWMON_CHANNEL_INFO(in,
48 			   HWMON_I_INPUT | HWMON_I_LABEL | HWMON_I_AVERAGE,
49 			   HWMON_I_INPUT | HWMON_I_LABEL,
50 			   HWMON_I_INPUT | HWMON_I_LABEL,
51 			   HWMON_I_INPUT | HWMON_I_LABEL,
52 			   HWMON_I_INPUT | HWMON_I_LABEL,
53 			   HWMON_I_INPUT | HWMON_I_LABEL),
54 	HWMON_CHANNEL_INFO(curr,
55 			   HWMON_C_INPUT | HWMON_C_LABEL | HWMON_C_AVERAGE),
56 	    HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_LABEL),
57 	NULL
58 };
59 
60 static int powerz_read_string(struct device *dev, enum hwmon_sensor_types type,
61 			      u32 attr, int channel, const char **str)
62 {
63 	if (type == hwmon_curr && attr == hwmon_curr_label) {
64 		*str = "IBUS";
65 	} else if (type == hwmon_in && attr == hwmon_in_label) {
66 		if (channel == 0)
67 			*str = "VBUS";
68 		else if (channel == 1)
69 			*str = "VCC1";
70 		else if (channel == 2)
71 			*str = "VCC2";
72 		else if (channel == 3)
73 			*str = "VDP";
74 		else if (channel == 4)
75 			*str = "VDM";
76 		else if (channel == 5)
77 			*str = "VDD";
78 		else
79 			return -EOPNOTSUPP;
80 	} else if (type == hwmon_temp && attr == hwmon_temp_label) {
81 		*str = "TEMP";
82 	} else {
83 		return -EOPNOTSUPP;
84 	}
85 
86 	return 0;
87 }
88 
89 static void powerz_usb_data_complete(struct urb *urb)
90 {
91 	struct powerz_priv *priv = urb->context;
92 
93 	complete(&priv->completion);
94 }
95 
96 static void powerz_usb_cmd_complete(struct urb *urb)
97 {
98 	struct powerz_priv *priv = urb->context;
99 
100 	usb_fill_bulk_urb(urb, urb->dev,
101 			  usb_rcvbulkpipe(urb->dev, POWERZ_EP_DATA_IN),
102 			  priv->transfer_buffer, sizeof(priv->transfer_buffer),
103 			  powerz_usb_data_complete, priv);
104 
105 	priv->status = usb_submit_urb(urb, GFP_ATOMIC);
106 	if (priv->status)
107 		complete(&priv->completion);
108 }
109 
110 static int powerz_read_data(struct usb_device *udev, struct powerz_priv *priv)
111 {
112 	long rc;
113 	int ret;
114 
115 	if (!priv->urb)
116 		return -ENODEV;
117 
118 	priv->status = -ETIMEDOUT;
119 	reinit_completion(&priv->completion);
120 
121 	priv->transfer_buffer[0] = 0x0c;
122 	priv->transfer_buffer[1] = 0x00;
123 	priv->transfer_buffer[2] = 0x02;
124 	priv->transfer_buffer[3] = 0x00;
125 
126 	usb_fill_bulk_urb(priv->urb, udev,
127 			  usb_sndbulkpipe(udev, POWERZ_EP_CMD_OUT),
128 			  priv->transfer_buffer, 4, powerz_usb_cmd_complete,
129 			  priv);
130 	ret = usb_submit_urb(priv->urb, GFP_KERNEL);
131 	if (ret)
132 		return ret;
133 
134 	rc = wait_for_completion_interruptible_timeout(&priv->completion,
135 						       msecs_to_jiffies(5));
136 	if (rc < 0) {
137 		usb_kill_urb(priv->urb);
138 		return rc;
139 	}
140 
141 	if (rc == 0) {
142 		usb_kill_urb(priv->urb);
143 		return -EIO;
144 	}
145 
146 	if (priv->urb->actual_length < sizeof(struct powerz_sensor_data))
147 		return -EIO;
148 
149 	return priv->status;
150 }
151 
152 static int powerz_read(struct device *dev, enum hwmon_sensor_types type,
153 		       u32 attr, int channel, long *val)
154 {
155 	struct usb_interface *intf = to_usb_interface(dev->parent);
156 	struct usb_device *udev = interface_to_usbdev(intf);
157 	struct powerz_priv *priv = usb_get_intfdata(intf);
158 	struct powerz_sensor_data *data;
159 	int ret;
160 
161 	if (!priv)
162 		return -EIO;	/* disconnected */
163 
164 	mutex_lock(&priv->mutex);
165 	ret = powerz_read_data(udev, priv);
166 	if (ret)
167 		goto out;
168 
169 	data = (struct powerz_sensor_data *)priv->transfer_buffer;
170 
171 	if (type == hwmon_curr) {
172 		if (attr == hwmon_curr_input)
173 			*val = ((s32)le32_to_cpu(data->I_bus)) / 1000;
174 		else if (attr == hwmon_curr_average)
175 			*val = ((s32)le32_to_cpu(data->I_bus_avg)) / 1000;
176 		else
177 			ret = -EOPNOTSUPP;
178 	} else if (type == hwmon_in) {
179 		if (attr == hwmon_in_input) {
180 			if (channel == 0)
181 				*val = le32_to_cpu(data->V_bus) / 1000;
182 			else if (channel == 1)
183 				*val = le16_to_cpu(data->V_cc1) / 10;
184 			else if (channel == 2)
185 				*val = le16_to_cpu(data->V_cc2) / 10;
186 			else if (channel == 3)
187 				*val = le16_to_cpu(data->V_dp) / 10;
188 			else if (channel == 4)
189 				*val = le16_to_cpu(data->V_dm) / 10;
190 			else if (channel == 5)
191 				*val = le16_to_cpu(data->V_dd) / 10;
192 			else
193 				ret = -EOPNOTSUPP;
194 		} else if (attr == hwmon_in_average && channel == 0) {
195 			*val = le32_to_cpu(data->V_bus_avg) / 1000;
196 		} else {
197 			ret = -EOPNOTSUPP;
198 		}
199 	} else if (type == hwmon_temp && attr == hwmon_temp_input) {
200 		*val = data->temp[1] * 2000 + data->temp[0] * 1000 / 128;
201 	} else {
202 		ret = -EOPNOTSUPP;
203 	}
204 
205 out:
206 	mutex_unlock(&priv->mutex);
207 	return ret;
208 }
209 
210 static const struct hwmon_ops powerz_hwmon_ops = {
211 	.visible = 0444,
212 	.read = powerz_read,
213 	.read_string = powerz_read_string,
214 };
215 
216 static const struct hwmon_chip_info powerz_chip_info = {
217 	.ops = &powerz_hwmon_ops,
218 	.info = powerz_info,
219 };
220 
221 static int powerz_probe(struct usb_interface *intf,
222 			const struct usb_device_id *id)
223 {
224 	struct powerz_priv *priv;
225 	struct device *hwmon_dev;
226 	struct device *parent;
227 
228 	parent = &intf->dev;
229 
230 	priv = devm_kzalloc(parent, sizeof(*priv), GFP_KERNEL);
231 	if (!priv)
232 		return -ENOMEM;
233 
234 	priv->urb = usb_alloc_urb(0, GFP_KERNEL);
235 	if (!priv->urb)
236 		return -ENOMEM;
237 	mutex_init(&priv->mutex);
238 	init_completion(&priv->completion);
239 
240 	usb_set_intfdata(intf, priv);
241 
242 	hwmon_dev =
243 	    devm_hwmon_device_register_with_info(parent, DRIVER_NAME, priv,
244 						 &powerz_chip_info, NULL);
245 	if (IS_ERR(hwmon_dev)) {
246 		usb_free_urb(priv->urb);
247 		return PTR_ERR(hwmon_dev);
248 	}
249 
250 	return 0;
251 }
252 
253 static void powerz_disconnect(struct usb_interface *intf)
254 {
255 	struct powerz_priv *priv = usb_get_intfdata(intf);
256 
257 	mutex_lock(&priv->mutex);
258 	usb_kill_urb(priv->urb);
259 	usb_free_urb(priv->urb);
260 	priv->urb = NULL;
261 	mutex_unlock(&priv->mutex);
262 }
263 
264 static const struct usb_device_id powerz_id_table[] = {
265 	{ USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0061, 0x00) },	/* ChargerLAB POWER-Z KM002C */
266 	{ USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0063, 0x00) },	/* ChargerLAB POWER-Z KM003C */
267 	{ }
268 };
269 
270 MODULE_DEVICE_TABLE(usb, powerz_id_table);
271 
272 static struct usb_driver powerz_driver = {
273 	.name = DRIVER_NAME,
274 	.id_table = powerz_id_table,
275 	.probe = powerz_probe,
276 	.disconnect = powerz_disconnect,
277 };
278 
279 module_usb_driver(powerz_driver);
280 
281 MODULE_LICENSE("GPL");
282 MODULE_AUTHOR("Thomas Weißschuh <linux@weissschuh.net>");
283 MODULE_DESCRIPTION("ChargerLAB POWER-Z USB-C tester");
284