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 scnprintf(buf, PAGE_SIZE, "%.*s\n", (int)sizeof(resp.value), 123 (char *)&resp.value); 124 } 125 126 static ssize_t version_show(struct device *dev, struct device_attribute *attr, 127 char *buf) 128 { 129 return get_info(dev, buf, CMD_GET_EC_LABEL); 130 } 131 132 static DEVICE_ATTR_RO(version); 133 134 static ssize_t build_revision_show(struct device *dev, 135 struct device_attribute *attr, char *buf) 136 { 137 return get_info(dev, buf, CMD_GET_EC_REV); 138 } 139 140 static DEVICE_ATTR_RO(build_revision); 141 142 static ssize_t build_date_show(struct device *dev, 143 struct device_attribute *attr, char *buf) 144 { 145 return get_info(dev, buf, CMD_GET_EC_BUILD_DATE); 146 } 147 148 static DEVICE_ATTR_RO(build_date); 149 150 static ssize_t model_number_show(struct device *dev, 151 struct device_attribute *attr, char *buf) 152 { 153 return get_info(dev, buf, CMD_GET_EC_MODEL); 154 } 155 156 static DEVICE_ATTR_RO(model_number); 157 158 static int send_usb_charge(struct wilco_ec_device *ec, 159 struct usb_charge_request *rq, 160 struct usb_charge_response *rs) 161 { 162 struct wilco_ec_message msg; 163 int ret; 164 165 memset(&msg, 0, sizeof(msg)); 166 msg.type = WILCO_EC_MSG_LEGACY; 167 msg.request_data = rq; 168 msg.request_size = sizeof(*rq); 169 msg.response_data = rs; 170 msg.response_size = sizeof(*rs); 171 ret = wilco_ec_mailbox(ec, &msg); 172 if (ret < 0) 173 return ret; 174 if (rs->status) 175 return -EIO; 176 177 return 0; 178 } 179 180 static ssize_t usb_charge_show(struct device *dev, 181 struct device_attribute *attr, char *buf) 182 { 183 struct wilco_ec_device *ec = dev_get_drvdata(dev); 184 struct usb_charge_request rq; 185 struct usb_charge_response rs; 186 int ret; 187 188 memset(&rq, 0, sizeof(rq)); 189 rq.cmd = CMD_USB_CHARGE; 190 rq.op = USB_CHARGE_GET; 191 192 ret = send_usb_charge(ec, &rq, &rs); 193 if (ret < 0) 194 return ret; 195 196 return sprintf(buf, "%d\n", rs.val); 197 } 198 199 static ssize_t usb_charge_store(struct device *dev, 200 struct device_attribute *attr, 201 const char *buf, size_t count) 202 { 203 struct wilco_ec_device *ec = dev_get_drvdata(dev); 204 struct usb_charge_request rq; 205 struct usb_charge_response rs; 206 int ret; 207 u8 val; 208 209 ret = kstrtou8(buf, 10, &val); 210 if (ret < 0) 211 return ret; 212 if (val > 1) 213 return -EINVAL; 214 215 memset(&rq, 0, sizeof(rq)); 216 rq.cmd = CMD_USB_CHARGE; 217 rq.op = USB_CHARGE_SET; 218 rq.val = val; 219 220 ret = send_usb_charge(ec, &rq, &rs); 221 if (ret < 0) 222 return ret; 223 224 return count; 225 } 226 227 static DEVICE_ATTR_RW(usb_charge); 228 229 static struct attribute *wilco_dev_attrs[] = { 230 &dev_attr_boot_on_ac.attr, 231 &dev_attr_build_date.attr, 232 &dev_attr_build_revision.attr, 233 &dev_attr_model_number.attr, 234 &dev_attr_usb_charge.attr, 235 &dev_attr_version.attr, 236 NULL, 237 }; 238 239 static struct attribute_group wilco_dev_attr_group = { 240 .attrs = wilco_dev_attrs, 241 }; 242 243 int wilco_ec_add_sysfs(struct wilco_ec_device *ec) 244 { 245 return sysfs_create_group(&ec->dev->kobj, &wilco_dev_attr_group); 246 } 247 248 void wilco_ec_remove_sysfs(struct wilco_ec_device *ec) 249 { 250 sysfs_remove_group(&ec->dev->kobj, &wilco_dev_attr_group); 251 } 252