1 // SPDX-License-Identifier: GPL-2.0+
3  * Surface Book (2 and later) hot-plug driver.
5  * Surface Book devices (can) have a hot-pluggable discrete GPU (dGPU). This
6  * driver is responsible for out-of-band hot-plug event signaling on these
7  * devices. It is specifically required when the hot-plug device is in D3cold
8  * and can thus not generate PCIe hot-plug events itself.
11  * device-check notifications to be picked up by the PCIe hot-plug driver.
13  * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
32 	{ "base_presence-int-gpio",   &shps_base_presence_int,   1 },
33 	{ "base_presence-gpio",       &shps_base_presence,       1 },
34 	{ "device_power-int-gpio",    &shps_device_power_int,    1 },
35 	{ "device_power-gpio",        &shps_device_power,        1 },
36 	{ "device_presence-int-gpio", &shps_device_presence_int, 1 },
37 	{ "device_presence-gpio",     &shps_device_presence,     1 },
41 /* 5515a847-ed55-4b27-8352-cd320e10360a */
75 #define SHPS_IRQ_NOT_PRESENT		((unsigned int)-1)
85 	acpi_handle handle = ACPI_HANDLE(&pdev->dev);  in shps_dsm_notify_irq()
90 	mutex_lock(&sdev->lock[type]);  in shps_dsm_notify_irq()
92 	value = gpiod_get_value_cansleep(sdev->gpio[type]);  in shps_dsm_notify_irq()
94 		mutex_unlock(&sdev->lock[type]);  in shps_dsm_notify_irq()
95 		dev_err(&pdev->dev, "failed to get gpio: %d (irq=%d)\n", type, value);  in shps_dsm_notify_irq()
99 	dev_dbg(&pdev->dev, "IRQ notification via DSM (irq=%d, value=%d)\n", type, value);  in shps_dsm_notify_irq()
107 		dev_err(&pdev->dev, "IRQ notification via DSM failed (irq=%d, gpio=%d)\n",  in shps_dsm_notify_irq()
110 	} else if (result->buffer.length != 1 || result->buffer.pointer[0] != 0) {  in shps_dsm_notify_irq()
111 		dev_err(&pdev->dev,  in shps_dsm_notify_irq()
116 	mutex_unlock(&sdev->lock[type]);  in shps_dsm_notify_irq()
129 		if (irq == sdev->irq[type])  in shps_handle_irq()
146 	acpi_handle handle = ACPI_HANDLE(&pdev->dev);  in shps_setup_irq()
157 		dev_dbg(&pdev->dev, "IRQ notification via DSM not present (irq=%d)\n", type);  in shps_setup_irq()
161 	gpiod = devm_gpiod_get(&pdev->dev, shps_gpio_names[type], GPIOD_ASIS);  in shps_setup_irq()
169 	irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "shps-irq-%d", type);  in shps_setup_irq()
171 		return -ENOMEM;  in shps_setup_irq()
173 	status = devm_request_threaded_irq(&pdev->dev, irq, NULL, shps_handle_irq,  in shps_setup_irq()
178 	dev_dbg(&pdev->dev, "set up irq %d as type %d\n", irq, type);  in shps_setup_irq()
180 	sdev->gpio[type] = gpiod;  in shps_setup_irq()
181 	sdev->irq[type] = irq;  in shps_setup_irq()
193 		if (sdev->irq[i] != SHPS_IRQ_NOT_PRESENT)  in surface_hotplug_remove()
194 			disable_irq(sdev->irq[i]);  in surface_hotplug_remove()
196 		mutex_destroy(&sdev->lock[i]);  in surface_hotplug_remove()
209 	 * however that doesn't have a hot-pluggable PCIe device. It also  in surface_hotplug_probe()
213 	if (gpiod_count(&pdev->dev, NULL) < 0)  in surface_hotplug_probe()
214 		return -ENODEV;  in surface_hotplug_probe()
216 	status = devm_acpi_dev_add_driver_gpios(&pdev->dev, shps_acpi_gpios);  in surface_hotplug_probe()
220 	sdev = devm_kzalloc(&pdev->dev, sizeof(*sdev), GFP_KERNEL);  in surface_hotplug_probe()
222 		return -ENOMEM;  in surface_hotplug_probe()
231 		sdev->irq[i] = SHPS_IRQ_NOT_PRESENT;  in surface_hotplug_probe()
235 		mutex_init(&sdev->lock[i]);  in surface_hotplug_probe()
239 			dev_err(&pdev->dev, "failed to set up IRQ %d: %d\n", i, status);  in surface_hotplug_probe()
244 	/* Ensure everything is up-to-date. */  in surface_hotplug_probe()
246 		if (sdev->irq[i] != SHPS_IRQ_NOT_PRESENT)  in surface_hotplug_probe()
274 MODULE_DESCRIPTION("Surface Hot-Plug Signaling Driver for Surface Book Devices");