1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright 2019 Google LLC 4 * 5 * Sysfs properties to view and modify EC-controlled features on Wilco devices. 6 * The entries will appear under /sys/bus/platform/devices/GOOG000C:00/ 7 * 8 * See Documentation/ABI/testing/sysfs-platform-wilco-ec for more information. 9 */ 10 11 #include <linux/device.h> 12 #include <linux/kernel.h> 13 #include <linux/platform_data/wilco-ec.h> 14 #include <linux/string.h> 15 #include <linux/sysfs.h> 16 #include <linux/types.h> 17 18 #define CMD_KB_CMOS 0x7C 19 #define SUB_CMD_KB_CMOS_AUTO_ON 0x03 20 21 struct boot_on_ac_request { 22 u8 cmd; /* Always CMD_KB_CMOS */ 23 u8 reserved1; 24 u8 sub_cmd; /* Always SUB_CMD_KB_CMOS_AUTO_ON */ 25 u8 reserved3to5[3]; 26 u8 val; /* Either 0 or 1 */ 27 u8 reserved7; 28 } __packed; 29 30 #define CMD_USB_CHARGE 0x39 31 32 enum usb_charge_op { 33 USB_CHARGE_GET = 0, 34 USB_CHARGE_SET = 1, 35 }; 36 37 struct usb_charge_request { 38 u8 cmd; /* Always CMD_USB_CHARGE */ 39 u8 reserved; 40 u8 op; /* One of enum usb_charge_op */ 41 u8 val; /* When setting, either 0 or 1 */ 42 } __packed; 43 44 struct usb_charge_response { 45 u8 reserved; 46 u8 status; /* Set by EC to 0 on success, other value on failure */ 47 u8 val; /* When getting, set by EC to either 0 or 1 */ 48 } __packed; 49 50 #define CMD_EC_INFO 0x38 51 enum get_ec_info_op { 52 CMD_GET_EC_LABEL = 0, 53 CMD_GET_EC_REV = 1, 54 CMD_GET_EC_MODEL = 2, 55 CMD_GET_EC_BUILD_DATE = 3, 56 }; 57 58 struct get_ec_info_req { 59 u8 cmd; /* Always CMD_EC_INFO */ 60 u8 reserved; 61 u8 op; /* One of enum get_ec_info_op */ 62 } __packed; 63 64 struct get_ec_info_resp { 65 u8 reserved[2]; 66 char value[9]; /* __nonstring: might not be null terminated */ 67 } __packed; 68 69 static ssize_t boot_on_ac_store(struct device *dev, 70 struct device_attribute *attr, 71 const char *buf, size_t count) 72 { 73 struct wilco_ec_device *ec = dev_get_drvdata(dev); 74 struct boot_on_ac_request rq; 75 struct wilco_ec_message msg; 76 int ret; 77 u8 val; 78 79 ret = kstrtou8(buf, 10, &val); 80 if (ret < 0) 81 return ret; 82 if (val > 1) 83 return -EINVAL; 84 85 memset(&rq, 0, sizeof(rq)); 86 rq.cmd = CMD_KB_CMOS; 87 rq.sub_cmd = SUB_CMD_KB_CMOS_AUTO_ON; 88 rq.val = val; 89 90 memset(&msg, 0, sizeof(msg)); 91 msg.type = WILCO_EC_MSG_LEGACY; 92 msg.request_data = &rq; 93 msg.request_size = sizeof(rq); 94 ret = wilco_ec_mailbox(ec, &msg); 95 if (ret < 0) 96 return ret; 97 98 return count; 99 } 100 101 static DEVICE_ATTR_WO(boot_on_ac); 102 103 static ssize_t get_info(struct device *dev, char *buf, enum get_ec_info_op op) 104 { 105 struct wilco_ec_device *ec = dev_get_drvdata(dev); 106 struct get_ec_info_req req = { .cmd = CMD_EC_INFO, .op = op }; 107 struct get_ec_info_resp resp; 108 int ret; 109 110 struct wilco_ec_message msg = { 111 .type = WILCO_EC_MSG_LEGACY, 112 .request_data = &req, 113 .request_size = sizeof(req), 114 .response_data = &resp, 115 .response_size = sizeof(resp), 116 }; 117 118 ret = wilco_ec_mailbox(ec, &msg); 119 if (ret < 0) 120 return ret; 121 122 return sysfs_emit(buf, "%.*s\n", (int)sizeof(resp.value), (char *)&resp.value); 123 } 124 125 static ssize_t version_show(struct device *dev, struct device_attribute *attr, 126 char *buf) 127 { 128 return get_info(dev, buf, CMD_GET_EC_LABEL); 129 } 130 131 static DEVICE_ATTR_RO(version); 132 133 static ssize_t build_revision_show(struct device *dev, 134 struct device_attribute *attr, char *buf) 135 { 136 return get_info(dev, buf, CMD_GET_EC_REV); 137 } 138 139 static DEVICE_ATTR_RO(build_revision); 140 141 static ssize_t build_date_show(struct device *dev, 142 struct device_attribute *attr, char *buf) 143 { 144 return get_info(dev, buf, CMD_GET_EC_BUILD_DATE); 145 } 146 147 static DEVICE_ATTR_RO(build_date); 148 149 static ssize_t model_number_show(struct device *dev, 150 struct device_attribute *attr, char *buf) 151 { 152 return get_info(dev, buf, CMD_GET_EC_MODEL); 153 } 154 155 static DEVICE_ATTR_RO(model_number); 156 157 static int send_usb_charge(struct wilco_ec_device *ec, 158 struct usb_charge_request *rq, 159 struct usb_charge_response *rs) 160 { 161 struct wilco_ec_message msg; 162 int ret; 163 164 memset(&msg, 0, sizeof(msg)); 165 msg.type = WILCO_EC_MSG_LEGACY; 166 msg.request_data = rq; 167 msg.request_size = sizeof(*rq); 168 msg.response_data = rs; 169 msg.response_size = sizeof(*rs); 170 ret = wilco_ec_mailbox(ec, &msg); 171 if (ret < 0) 172 return ret; 173 if (rs->status) 174 return -EIO; 175 176 return 0; 177 } 178 179 static ssize_t usb_charge_show(struct device *dev, 180 struct device_attribute *attr, char *buf) 181 { 182 struct wilco_ec_device *ec = dev_get_drvdata(dev); 183 struct usb_charge_request rq; 184 struct usb_charge_response rs; 185 int ret; 186 187 memset(&rq, 0, sizeof(rq)); 188 rq.cmd = CMD_USB_CHARGE; 189 rq.op = USB_CHARGE_GET; 190 191 ret = send_usb_charge(ec, &rq, &rs); 192 if (ret < 0) 193 return ret; 194 195 return sysfs_emit(buf, "%d\n", rs.val); 196 } 197 198 static ssize_t usb_charge_store(struct device *dev, 199 struct device_attribute *attr, 200 const char *buf, size_t count) 201 { 202 struct wilco_ec_device *ec = dev_get_drvdata(dev); 203 struct usb_charge_request rq; 204 struct usb_charge_response rs; 205 int ret; 206 u8 val; 207 208 ret = kstrtou8(buf, 10, &val); 209 if (ret < 0) 210 return ret; 211 if (val > 1) 212 return -EINVAL; 213 214 memset(&rq, 0, sizeof(rq)); 215 rq.cmd = CMD_USB_CHARGE; 216 rq.op = USB_CHARGE_SET; 217 rq.val = val; 218 219 ret = send_usb_charge(ec, &rq, &rs); 220 if (ret < 0) 221 return ret; 222 223 return count; 224 } 225 226 static DEVICE_ATTR_RW(usb_charge); 227 228 static struct attribute *wilco_dev_attrs[] = { 229 &dev_attr_boot_on_ac.attr, 230 &dev_attr_build_date.attr, 231 &dev_attr_build_revision.attr, 232 &dev_attr_model_number.attr, 233 &dev_attr_usb_charge.attr, 234 &dev_attr_version.attr, 235 NULL, 236 }; 237 238 static const struct attribute_group wilco_dev_attr_group = { 239 .attrs = wilco_dev_attrs, 240 }; 241 242 int wilco_ec_add_sysfs(struct wilco_ec_device *ec) 243 { 244 return sysfs_create_group(&ec->dev->kobj, &wilco_dev_attr_group); 245 } 246 247 void wilco_ec_remove_sysfs(struct wilco_ec_device *ec) 248 { 249 sysfs_remove_group(&ec->dev->kobj, &wilco_dev_attr_group); 250 } 251