Maximilian Luz | fc622b3 | 2021-02-12 12:54:34 +0100 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * Surface System Aggregator Module (SSAM) client device registry. |
| 4 | * |
| 5 | * Registry for non-platform/non-ACPI SSAM client devices, i.e. devices that |
| 6 | * cannot be auto-detected. Provides device-hubs and performs instantiation |
| 7 | * for these devices. |
| 8 | * |
| 9 | * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com> |
| 10 | */ |
| 11 | |
| 12 | #include <linux/acpi.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/platform_device.h> |
| 16 | #include <linux/property.h> |
| 17 | |
| 18 | #include <linux/surface_aggregator/controller.h> |
| 19 | #include <linux/surface_aggregator/device.h> |
| 20 | |
| 21 | |
| 22 | /* -- Device registry. ------------------------------------------------------ */ |
| 23 | |
| 24 | /* |
| 25 | * SSAM device names follow the SSAM module alias, meaning they are prefixed |
| 26 | * with 'ssam:', followed by domain, category, target ID, instance ID, and |
| 27 | * function, each encoded as two-digit hexadecimal, separated by ':'. In other |
| 28 | * words, it follows the scheme |
| 29 | * |
| 30 | * ssam:dd:cc:tt:ii:ff |
| 31 | * |
| 32 | * Where, 'dd', 'cc', 'tt', 'ii', and 'ff' are the two-digit hexadecimal |
| 33 | * values mentioned above, respectively. |
| 34 | */ |
| 35 | |
| 36 | /* Root node. */ |
| 37 | static const struct software_node ssam_node_root = { |
| 38 | .name = "ssam_platform_hub", |
| 39 | }; |
| 40 | |
| 41 | /* Devices for Surface Book 2. */ |
| 42 | static const struct software_node *ssam_node_group_sb2[] = { |
| 43 | &ssam_node_root, |
| 44 | NULL, |
| 45 | }; |
| 46 | |
| 47 | /* Devices for Surface Book 3. */ |
| 48 | static const struct software_node *ssam_node_group_sb3[] = { |
| 49 | &ssam_node_root, |
| 50 | NULL, |
| 51 | }; |
| 52 | |
| 53 | /* Devices for Surface Laptop 1. */ |
| 54 | static const struct software_node *ssam_node_group_sl1[] = { |
| 55 | &ssam_node_root, |
| 56 | NULL, |
| 57 | }; |
| 58 | |
| 59 | /* Devices for Surface Laptop 2. */ |
| 60 | static const struct software_node *ssam_node_group_sl2[] = { |
| 61 | &ssam_node_root, |
| 62 | NULL, |
| 63 | }; |
| 64 | |
| 65 | /* Devices for Surface Laptop 3. */ |
| 66 | static const struct software_node *ssam_node_group_sl3[] = { |
| 67 | &ssam_node_root, |
| 68 | NULL, |
| 69 | }; |
| 70 | |
| 71 | /* Devices for Surface Laptop Go. */ |
| 72 | static const struct software_node *ssam_node_group_slg1[] = { |
| 73 | &ssam_node_root, |
| 74 | NULL, |
| 75 | }; |
| 76 | |
| 77 | /* Devices for Surface Pro 5. */ |
| 78 | static const struct software_node *ssam_node_group_sp5[] = { |
| 79 | &ssam_node_root, |
| 80 | NULL, |
| 81 | }; |
| 82 | |
| 83 | /* Devices for Surface Pro 6. */ |
| 84 | static const struct software_node *ssam_node_group_sp6[] = { |
| 85 | &ssam_node_root, |
| 86 | NULL, |
| 87 | }; |
| 88 | |
| 89 | /* Devices for Surface Pro 7. */ |
| 90 | static const struct software_node *ssam_node_group_sp7[] = { |
| 91 | &ssam_node_root, |
| 92 | NULL, |
| 93 | }; |
| 94 | |
| 95 | |
| 96 | /* -- Device registry helper functions. ------------------------------------- */ |
| 97 | |
| 98 | static int ssam_uid_from_string(const char *str, struct ssam_device_uid *uid) |
| 99 | { |
| 100 | u8 d, tc, tid, iid, fn; |
| 101 | int n; |
| 102 | |
| 103 | n = sscanf(str, "ssam:%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn); |
| 104 | if (n != 5) |
| 105 | return -EINVAL; |
| 106 | |
| 107 | uid->domain = d; |
| 108 | uid->category = tc; |
| 109 | uid->target = tid; |
| 110 | uid->instance = iid; |
| 111 | uid->function = fn; |
| 112 | |
| 113 | return 0; |
| 114 | } |
| 115 | |
| 116 | static int ssam_hub_remove_devices_fn(struct device *dev, void *data) |
| 117 | { |
| 118 | if (!is_ssam_device(dev)) |
| 119 | return 0; |
| 120 | |
| 121 | ssam_device_remove(to_ssam_device(dev)); |
| 122 | return 0; |
| 123 | } |
| 124 | |
| 125 | static void ssam_hub_remove_devices(struct device *parent) |
| 126 | { |
| 127 | device_for_each_child_reverse(parent, NULL, ssam_hub_remove_devices_fn); |
| 128 | } |
| 129 | |
| 130 | static int ssam_hub_add_device(struct device *parent, struct ssam_controller *ctrl, |
| 131 | struct fwnode_handle *node) |
| 132 | { |
| 133 | struct ssam_device_uid uid; |
| 134 | struct ssam_device *sdev; |
| 135 | int status; |
| 136 | |
| 137 | status = ssam_uid_from_string(fwnode_get_name(node), &uid); |
| 138 | if (status) |
| 139 | return status; |
| 140 | |
| 141 | sdev = ssam_device_alloc(ctrl, uid); |
| 142 | if (!sdev) |
| 143 | return -ENOMEM; |
| 144 | |
| 145 | sdev->dev.parent = parent; |
| 146 | sdev->dev.fwnode = node; |
| 147 | |
| 148 | status = ssam_device_add(sdev); |
| 149 | if (status) |
| 150 | ssam_device_put(sdev); |
| 151 | |
| 152 | return status; |
| 153 | } |
| 154 | |
| 155 | static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *ctrl, |
| 156 | struct fwnode_handle *node) |
| 157 | { |
| 158 | struct fwnode_handle *child; |
| 159 | int status; |
| 160 | |
| 161 | fwnode_for_each_child_node(node, child) { |
| 162 | /* |
| 163 | * Try to add the device specified in the firmware node. If |
| 164 | * this fails with -EINVAL, the node does not specify any SSAM |
| 165 | * device, so ignore it and continue with the next one. |
| 166 | */ |
| 167 | |
| 168 | status = ssam_hub_add_device(parent, ctrl, child); |
| 169 | if (status && status != -EINVAL) |
| 170 | goto err; |
| 171 | } |
| 172 | |
| 173 | return 0; |
| 174 | err: |
| 175 | ssam_hub_remove_devices(parent); |
| 176 | return status; |
| 177 | } |
| 178 | |
| 179 | |
| 180 | /* -- SSAM platform/meta-hub driver. ---------------------------------------- */ |
| 181 | |
| 182 | static const struct acpi_device_id ssam_platform_hub_match[] = { |
| 183 | /* Surface Pro 4, 5, and 6 (OMBR < 0x10) */ |
| 184 | { "MSHW0081", (unsigned long)ssam_node_group_sp5 }, |
| 185 | |
| 186 | /* Surface Pro 6 (OMBR >= 0x10) */ |
| 187 | { "MSHW0111", (unsigned long)ssam_node_group_sp6 }, |
| 188 | |
| 189 | /* Surface Pro 7 */ |
| 190 | { "MSHW0116", (unsigned long)ssam_node_group_sp7 }, |
| 191 | |
| 192 | /* Surface Book 2 */ |
| 193 | { "MSHW0107", (unsigned long)ssam_node_group_sb2 }, |
| 194 | |
| 195 | /* Surface Book 3 */ |
| 196 | { "MSHW0117", (unsigned long)ssam_node_group_sb3 }, |
| 197 | |
| 198 | /* Surface Laptop 1 */ |
| 199 | { "MSHW0086", (unsigned long)ssam_node_group_sl1 }, |
| 200 | |
| 201 | /* Surface Laptop 2 */ |
| 202 | { "MSHW0112", (unsigned long)ssam_node_group_sl2 }, |
| 203 | |
| 204 | /* Surface Laptop 3 (13", Intel) */ |
| 205 | { "MSHW0114", (unsigned long)ssam_node_group_sl3 }, |
| 206 | |
| 207 | /* Surface Laptop 3 (15", AMD) */ |
| 208 | { "MSHW0110", (unsigned long)ssam_node_group_sl3 }, |
| 209 | |
| 210 | /* Surface Laptop Go 1 */ |
| 211 | { "MSHW0118", (unsigned long)ssam_node_group_slg1 }, |
| 212 | |
| 213 | { }, |
| 214 | }; |
| 215 | MODULE_DEVICE_TABLE(acpi, ssam_platform_hub_match); |
| 216 | |
| 217 | static int ssam_platform_hub_probe(struct platform_device *pdev) |
| 218 | { |
| 219 | const struct software_node **nodes; |
| 220 | struct ssam_controller *ctrl; |
| 221 | struct fwnode_handle *root; |
| 222 | int status; |
| 223 | |
| 224 | nodes = (const struct software_node **)acpi_device_get_match_data(&pdev->dev); |
| 225 | if (!nodes) |
| 226 | return -ENODEV; |
| 227 | |
| 228 | /* |
| 229 | * As we're adding the SSAM client devices as children under this device |
| 230 | * and not the SSAM controller, we need to add a device link to the |
| 231 | * controller to ensure that we remove all of our devices before the |
| 232 | * controller is removed. This also guarantees proper ordering for |
| 233 | * suspend/resume of the devices on this hub. |
| 234 | */ |
| 235 | ctrl = ssam_client_bind(&pdev->dev); |
| 236 | if (IS_ERR(ctrl)) |
| 237 | return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl); |
| 238 | |
| 239 | status = software_node_register_node_group(nodes); |
| 240 | if (status) |
| 241 | return status; |
| 242 | |
| 243 | root = software_node_fwnode(&ssam_node_root); |
| 244 | if (!root) { |
| 245 | software_node_unregister_node_group(nodes); |
| 246 | return -ENOENT; |
| 247 | } |
| 248 | |
| 249 | set_secondary_fwnode(&pdev->dev, root); |
| 250 | |
| 251 | status = ssam_hub_add_devices(&pdev->dev, ctrl, root); |
| 252 | if (status) { |
| 253 | set_secondary_fwnode(&pdev->dev, NULL); |
| 254 | software_node_unregister_node_group(nodes); |
| 255 | } |
| 256 | |
| 257 | platform_set_drvdata(pdev, nodes); |
| 258 | return status; |
| 259 | } |
| 260 | |
| 261 | static int ssam_platform_hub_remove(struct platform_device *pdev) |
| 262 | { |
| 263 | const struct software_node **nodes = platform_get_drvdata(pdev); |
| 264 | |
| 265 | ssam_hub_remove_devices(&pdev->dev); |
| 266 | set_secondary_fwnode(&pdev->dev, NULL); |
| 267 | software_node_unregister_node_group(nodes); |
| 268 | return 0; |
| 269 | } |
| 270 | |
| 271 | static struct platform_driver ssam_platform_hub_driver = { |
| 272 | .probe = ssam_platform_hub_probe, |
| 273 | .remove = ssam_platform_hub_remove, |
| 274 | .driver = { |
| 275 | .name = "surface_aggregator_platform_hub", |
| 276 | .acpi_match_table = ssam_platform_hub_match, |
| 277 | .probe_type = PROBE_PREFER_ASYNCHRONOUS, |
| 278 | }, |
| 279 | }; |
| 280 | module_platform_driver(ssam_platform_hub_driver); |
| 281 | |
| 282 | MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>"); |
| 283 | MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module"); |
| 284 | MODULE_LICENSE("GPL"); |