1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Platform driver for OneXPlayer, AOK ZOE, and Aya Neo Handhelds that expose 4 * fan reading and control via hwmon sysfs. 5 * 6 * Old OXP boards have the same DMI strings and they are told apart by 7 * the boot cpu vendor (Intel/AMD). Currently only AMD boards are 8 * supported but the code is made to be simple to add other handheld 9 * boards in the future. 10 * Fan control is provided via pwm interface in the range [0-255]. 11 * Old AMD boards use [0-100] as range in the EC, the written value is 12 * scaled to accommodate for that. Newer boards like the mini PRO and 13 * AOK ZOE are not scaled but have the same EC layout. 14 * 15 * Copyright (C) 2022 Joaquín I. Aramendía <samsagax@gmail.com> 16 */ 17 18 #include <linux/acpi.h> 19 #include <linux/dev_printk.h> 20 #include <linux/dmi.h> 21 #include <linux/hwmon.h> 22 #include <linux/init.h> 23 #include <linux/kernel.h> 24 #include <linux/module.h> 25 #include <linux/platform_device.h> 26 #include <linux/processor.h> 27 28 /* Handle ACPI lock mechanism */ 29 static u32 oxp_mutex; 30 31 #define ACPI_LOCK_DELAY_MS 500 32 33 static bool lock_global_acpi_lock(void) 34 { 35 return ACPI_SUCCESS(acpi_acquire_global_lock(ACPI_LOCK_DELAY_MS, &oxp_mutex)); 36 } 37 38 static bool unlock_global_acpi_lock(void) 39 { 40 return ACPI_SUCCESS(acpi_release_global_lock(oxp_mutex)); 41 } 42 43 enum oxp_board { 44 aok_zoe_a1 = 1, 45 aya_neo_2, 46 aya_neo_air, 47 aya_neo_air_pro, 48 aya_neo_geek, 49 oxp_mini_amd, 50 oxp_mini_amd_pro, 51 }; 52 53 static enum oxp_board board; 54 55 #define OXP_SENSOR_FAN_REG 0x76 /* Fan reading is 2 registers long */ 56 #define OXP_SENSOR_PWM_ENABLE_REG 0x4A /* PWM enable is 1 register long */ 57 #define OXP_SENSOR_PWM_REG 0x4B /* PWM reading is 1 register long */ 58 59 static const struct dmi_system_id dmi_table[] = { 60 { 61 .matches = { 62 DMI_MATCH(DMI_BOARD_VENDOR, "AOKZOE"), 63 DMI_EXACT_MATCH(DMI_BOARD_NAME, "AOKZOE A1 AR07"), 64 }, 65 .driver_data = (void *)aok_zoe_a1, 66 }, 67 { 68 .matches = { 69 DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"), 70 DMI_EXACT_MATCH(DMI_BOARD_NAME, "AYANEO 2"), 71 }, 72 .driver_data = (void *)aya_neo_2, 73 }, 74 { 75 .matches = { 76 DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"), 77 DMI_EXACT_MATCH(DMI_BOARD_NAME, "AIR"), 78 }, 79 .driver_data = (void *)aya_neo_air, 80 }, 81 { 82 .matches = { 83 DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"), 84 DMI_EXACT_MATCH(DMI_BOARD_NAME, "AIR Pro"), 85 }, 86 .driver_data = (void *)aya_neo_air_pro, 87 }, 88 { 89 .matches = { 90 DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"), 91 DMI_EXACT_MATCH(DMI_BOARD_NAME, "GEEK"), 92 }, 93 .driver_data = (void *)aya_neo_geek, 94 }, 95 { 96 .matches = { 97 DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"), 98 DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONE XPLAYER"), 99 }, 100 .driver_data = (void *)oxp_mini_amd, 101 }, 102 { 103 .matches = { 104 DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"), 105 DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONEXPLAYER mini A07"), 106 }, 107 .driver_data = (void *)oxp_mini_amd, 108 }, 109 { 110 .matches = { 111 DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"), 112 DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONEXPLAYER Mini Pro"), 113 }, 114 .driver_data = (void *)oxp_mini_amd_pro, 115 }, 116 {}, 117 }; 118 119 /* Helper functions to handle EC read/write */ 120 static int read_from_ec(u8 reg, int size, long *val) 121 { 122 int i; 123 int ret; 124 u8 buffer; 125 126 if (!lock_global_acpi_lock()) 127 return -EBUSY; 128 129 *val = 0; 130 for (i = 0; i < size; i++) { 131 ret = ec_read(reg + i, &buffer); 132 if (ret) 133 return ret; 134 *val <<= i * 8; 135 *val += buffer; 136 } 137 138 if (!unlock_global_acpi_lock()) 139 return -EBUSY; 140 141 return 0; 142 } 143 144 static int write_to_ec(const struct device *dev, u8 reg, u8 value) 145 { 146 int ret; 147 148 if (!lock_global_acpi_lock()) 149 return -EBUSY; 150 151 ret = ec_write(reg, value); 152 153 if (!unlock_global_acpi_lock()) 154 return -EBUSY; 155 156 return ret; 157 } 158 159 static int oxp_pwm_enable(const struct device *dev) 160 { 161 return write_to_ec(dev, OXP_SENSOR_PWM_ENABLE_REG, 0x01); 162 } 163 164 static int oxp_pwm_disable(const struct device *dev) 165 { 166 return write_to_ec(dev, OXP_SENSOR_PWM_ENABLE_REG, 0x00); 167 } 168 169 /* Callbacks for hwmon interface */ 170 static umode_t oxp_ec_hwmon_is_visible(const void *drvdata, 171 enum hwmon_sensor_types type, u32 attr, int channel) 172 { 173 switch (type) { 174 case hwmon_fan: 175 return 0444; 176 case hwmon_pwm: 177 return 0644; 178 default: 179 return 0; 180 } 181 } 182 183 static int oxp_platform_read(struct device *dev, enum hwmon_sensor_types type, 184 u32 attr, int channel, long *val) 185 { 186 int ret; 187 188 switch (type) { 189 case hwmon_fan: 190 switch (attr) { 191 case hwmon_fan_input: 192 return read_from_ec(OXP_SENSOR_FAN_REG, 2, val); 193 default: 194 break; 195 } 196 break; 197 case hwmon_pwm: 198 switch (attr) { 199 case hwmon_pwm_input: 200 ret = read_from_ec(OXP_SENSOR_PWM_REG, 1, val); 201 if (ret) 202 return ret; 203 switch (board) { 204 case aya_neo_2: 205 case aya_neo_air: 206 case aya_neo_air_pro: 207 case aya_neo_geek: 208 case oxp_mini_amd: 209 *val = (*val * 255) / 100; 210 break; 211 case oxp_mini_amd_pro: 212 case aok_zoe_a1: 213 default: 214 break; 215 } 216 return 0; 217 case hwmon_pwm_enable: 218 return read_from_ec(OXP_SENSOR_PWM_ENABLE_REG, 1, val); 219 default: 220 break; 221 } 222 break; 223 default: 224 break; 225 } 226 return -EOPNOTSUPP; 227 } 228 229 static int oxp_platform_write(struct device *dev, enum hwmon_sensor_types type, 230 u32 attr, int channel, long val) 231 { 232 switch (type) { 233 case hwmon_pwm: 234 switch (attr) { 235 case hwmon_pwm_enable: 236 if (val == 1) 237 return oxp_pwm_enable(dev); 238 else if (val == 0) 239 return oxp_pwm_disable(dev); 240 return -EINVAL; 241 case hwmon_pwm_input: 242 if (val < 0 || val > 255) 243 return -EINVAL; 244 switch (board) { 245 case aya_neo_2: 246 case aya_neo_air: 247 case aya_neo_air_pro: 248 case aya_neo_geek: 249 case oxp_mini_amd: 250 val = (val * 100) / 255; 251 break; 252 case aok_zoe_a1: 253 case oxp_mini_amd_pro: 254 default: 255 break; 256 } 257 return write_to_ec(dev, OXP_SENSOR_PWM_REG, val); 258 default: 259 break; 260 } 261 break; 262 default: 263 break; 264 } 265 return -EOPNOTSUPP; 266 } 267 268 /* Known sensors in the OXP EC controllers */ 269 static const struct hwmon_channel_info * const oxp_platform_sensors[] = { 270 HWMON_CHANNEL_INFO(fan, 271 HWMON_F_INPUT), 272 HWMON_CHANNEL_INFO(pwm, 273 HWMON_PWM_INPUT | HWMON_PWM_ENABLE), 274 NULL, 275 }; 276 277 static const struct hwmon_ops oxp_ec_hwmon_ops = { 278 .is_visible = oxp_ec_hwmon_is_visible, 279 .read = oxp_platform_read, 280 .write = oxp_platform_write, 281 }; 282 283 static const struct hwmon_chip_info oxp_ec_chip_info = { 284 .ops = &oxp_ec_hwmon_ops, 285 .info = oxp_platform_sensors, 286 }; 287 288 /* Initialization logic */ 289 static int oxp_platform_probe(struct platform_device *pdev) 290 { 291 const struct dmi_system_id *dmi_entry; 292 struct device *dev = &pdev->dev; 293 struct device *hwdev; 294 295 /* 296 * Have to check for AMD processor here because DMI strings are the 297 * same between Intel and AMD boards, the only way to tell them apart 298 * is the CPU. 299 * Intel boards seem to have different EC registers and values to 300 * read/write. 301 */ 302 dmi_entry = dmi_first_match(dmi_table); 303 if (!dmi_entry || boot_cpu_data.x86_vendor != X86_VENDOR_AMD) 304 return -ENODEV; 305 306 board = (enum oxp_board)(unsigned long)dmi_entry->driver_data; 307 308 hwdev = devm_hwmon_device_register_with_info(dev, "oxpec", NULL, 309 &oxp_ec_chip_info, NULL); 310 311 return PTR_ERR_OR_ZERO(hwdev); 312 } 313 314 static struct platform_driver oxp_platform_driver = { 315 .driver = { 316 .name = "oxp-platform", 317 }, 318 .probe = oxp_platform_probe, 319 }; 320 321 static struct platform_device *oxp_platform_device; 322 323 static int __init oxp_platform_init(void) 324 { 325 oxp_platform_device = 326 platform_create_bundle(&oxp_platform_driver, 327 oxp_platform_probe, NULL, 0, NULL, 0); 328 329 return PTR_ERR_OR_ZERO(oxp_platform_device); 330 } 331 332 static void __exit oxp_platform_exit(void) 333 { 334 platform_device_unregister(oxp_platform_device); 335 platform_driver_unregister(&oxp_platform_driver); 336 } 337 338 MODULE_DEVICE_TABLE(dmi, dmi_table); 339 340 module_init(oxp_platform_init); 341 module_exit(oxp_platform_exit); 342 343 MODULE_AUTHOR("Joaquín Ignacio Aramendía <samsagax@gmail.com>"); 344 MODULE_DESCRIPTION("Platform driver that handles EC sensors of OneXPlayer devices"); 345 MODULE_LICENSE("GPL"); 346