Input: atlas_btns - modernize the driver

Rework the driver to use modern style:

- Remove global state by introducing a per-device structure
- Use devm for resource management (input device allocation)
- Use dev_err_probe() for error reporting in the probe path
- Clean up unused definitions and headers.

Assisted-by: Gemini:gemini-3.1-pro
Link: https://patch.msgid.link/ahp6qt_viW3l-NlX@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/misc/atlas_btns.c b/drivers/input/misc/atlas_btns.c
index 835ad45a9d65c04e3d2f4feb351c1fef1b8b554a..5805a1a3bb057733c2eb71891b19290f7677a833 100644 (file)
--- a/drivers/input/misc/atlas_btns.c
+++ b/drivers/input/misc/atlas_btns.c
@@ -15,17 +15,18 @@
 #include <linux/types.h>
 #include <linux/acpi.h>
 #include <linux/platform_device.h>
-#include <linux/uaccess.h>
 
 #define ACPI_ATLAS_NAME                "Atlas ACPI"
-#define ACPI_ATLAS_CLASS       "Atlas"
 
-static unsigned short atlas_keymap[16];
-static struct input_dev *input_dev;
+struct atlas_btns {
+       struct input_dev *input_dev;
+       unsigned short keymap[16];
+};
 
 /* button handling code */
 static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
-                   u32 function, void *handler_context, void **return_context)
+                                          u32 function, void *handler_context,
+                                          void **return_context)
 {
        *return_context =
                (function != ACPI_REGION_DEACTIVATE) ? handler_context : NULL;
@@ -34,33 +35,37 @@ static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
 }
 
 static acpi_status acpi_atlas_button_handler(u32 function,
-                     acpi_physical_address address,
-                     u32 bit_width, u64 *value,
-                     void *handler_context, void *region_context)
+                                            acpi_physical_address address,
+                                            u32 bit_width, u64 *value,
+                                            void *handler_context,
+                                            void *region_context)
 {
-       acpi_status status;
+       struct atlas_btns *atlas = region_context;
 
        if (function == ACPI_WRITE) {
                int code = address & 0x0f;
                int key_down = !(address & 0x10);
 
-               input_event(input_dev, EV_MSC, MSC_SCAN, code);
-               input_report_key(input_dev, atlas_keymap[code], key_down);
-               input_sync(input_dev);
+               input_event(atlas->input_dev, EV_MSC, MSC_SCAN, code);
+               input_report_key(atlas->input_dev, atlas->keymap[code],
+                                key_down);
+               input_sync(atlas->input_dev);
 
-               status = AE_OK;
-       } else {
-               pr_warn("shrugged on unexpected function: function=%x,address=%lx,value=%x\n",
-                       function, (unsigned long)address, (u32)*value);
-               status = AE_BAD_PARAMETER;
+               return AE_OK;
        }
 
-       return status;
+       dev_warn(atlas->input_dev->dev.parent,
+                "unexpected function: function=%x,address=%lx,value=%x\n",
+                function, (unsigned long)address, (u32)*value);
+
+       return AE_BAD_PARAMETER;
 }
 
 static int atlas_acpi_button_probe(struct platform_device *pdev)
 {
        struct acpi_device *device;
+       struct atlas_btns *atlas;
+       struct input_dev *input_dev;
        acpi_status status;
        int i;
        int err;
@@ -69,65 +74,62 @@ static int atlas_acpi_button_probe(struct platform_device *pdev)
        if (!device)
                return -ENODEV;
 
-       input_dev = input_allocate_device();
-       if (!input_dev) {
-               pr_err("unable to allocate input device\n");
+       atlas = devm_kzalloc(&pdev->dev, sizeof(*atlas), GFP_KERNEL);
+       if (!atlas)
                return -ENOMEM;
-       }
+
+       input_dev = devm_input_allocate_device(&pdev->dev);
+       if (!input_dev)
+               return -ENOMEM;
+
+       atlas->input_dev = input_dev;
 
        input_dev->name = "Atlas ACPI button driver";
        input_dev->phys = "ASIM0000/atlas/input0";
        input_dev->id.bustype = BUS_HOST;
-       input_dev->keycode = atlas_keymap;
-       input_dev->keycodesize = sizeof(unsigned short);
-       input_dev->keycodemax = ARRAY_SIZE(atlas_keymap);
+       input_dev->keycode = atlas->keymap;
+       input_dev->keycodesize = sizeof(atlas->keymap[0]);
+       input_dev->keycodemax = ARRAY_SIZE(atlas->keymap);
 
        input_set_capability(input_dev, EV_MSC, MSC_SCAN);
-       __set_bit(EV_KEY, input_dev->evbit);
-       for (i = 0; i < ARRAY_SIZE(atlas_keymap); i++) {
+       for (i = 0; i < ARRAY_SIZE(atlas->keymap); i++) {
                if (i < 9) {
-                       atlas_keymap[i] = KEY_F1 + i;
-                       __set_bit(KEY_F1 + i, input_dev->keybit);
-               } else
-                       atlas_keymap[i] = KEY_RESERVED;
+                       atlas->keymap[i] = KEY_F1 + i;
+                       input_set_capability(input_dev, EV_KEY, KEY_F1 + i);
+               } else {
+                       atlas->keymap[i] = KEY_RESERVED;
+               }
        }
 
        err = input_register_device(input_dev);
-       if (err) {
-               pr_err("couldn't register input device\n");
-               input_free_device(input_dev);
-               return err;
-       }
+       if (err)
+               return dev_err_probe(&pdev->dev, err,
+                                    "couldn't register input device\n");
 
        /* hookup button handler */
        status = acpi_install_address_space_handler(device->handle,
-                               0x81, &acpi_atlas_button_handler,
-                               &acpi_atlas_button_setup, device);
-       if (ACPI_FAILURE(status)) {
-               pr_err("error installing addr spc handler\n");
-               input_unregister_device(input_dev);
-               err = -EINVAL;
-       }
+                                                   0x81,
+                                                   &acpi_atlas_button_handler,
+                                                   &acpi_atlas_button_setup,
+                                                   atlas);
+       if (ACPI_FAILURE(status))
+               return dev_err_probe(&pdev->dev, -EINVAL,
+                                    "error installing addr spc handler\n");
 
-       return err;
+       return 0;
 }
 
 static void atlas_acpi_button_remove(struct platform_device *pdev)
 {
        struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
-       acpi_status status;
 
-       status = acpi_remove_address_space_handler(device->handle,
-                               0x81, &acpi_atlas_button_handler);
-       if (ACPI_FAILURE(status))
-               pr_err("error removing addr spc handler\n");
-
-       input_unregister_device(input_dev);
+       acpi_remove_address_space_handler(device->handle, 0x81,
+                                         &acpi_atlas_button_handler);
 }
 
 static const struct acpi_device_id atlas_device_ids[] = {
-       {"ASIM0000", 0},
-       {"", 0},
+       { "ASIM0000" },
+       { "" }
 };
 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
 
@@ -144,4 +146,3 @@ module_platform_driver(atlas_acpi_driver);
 MODULE_AUTHOR("Jaya Kumar");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Atlas button driver");
-