drivers/pwm/pwm-lpss-platform.c

1 // SPDX-License-Identifier: GPL-2.0-only
3  * Intel Low Power Subsystem PWM controller driver
7  * Derived from the original pwm-lpss.c
17 #include "pwm-lpss.h"
26 	info = device_get_match_data(&pdev->dev);  in pwm_lpss_probe_platform()
28 		return -ENODEV;  in pwm_lpss_probe_platform()
34 	lpwm = devm_pwm_lpss_probe(&pdev->dev, base, info);  in pwm_lpss_probe_platform()
41 	 * On Cherry Trail devices the GFX0._PS0 AML checks if the controller  in pwm_lpss_probe_platform()
43 	 * believes is the correct state to the PWM controller.  in pwm_lpss_probe_platform()
44 	 * Because of this we must disallow direct-complete, which keeps the  in pwm_lpss_probe_platform()
45 	 * controller (runtime)suspended on resume, to avoid 2 issues:  in pwm_lpss_probe_platform()
46 	 * 1. The controller getting turned on without the linux-pm code  in pwm_lpss_probe_platform()
47 	 *    knowing about this. On devices where the controller is unused  in pwm_lpss_probe_platform()
50 	 * 2. The state restoring code unexpectedly messing with the controller  in pwm_lpss_probe_platform()
52 	 * Leaving the controller runtime-suspended (skipping runtime-resume +  in pwm_lpss_probe_platform()
53 	 * normal-suspend) during suspend is fine.  in pwm_lpss_probe_platform()
55 	if (info->other_devices_aml_touches_pwm_regs)  in pwm_lpss_probe_platform()
56 		dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE|  in pwm_lpss_probe_platform()
59 	pm_runtime_set_active(&pdev->dev);  in pwm_lpss_probe_platform()
60 	pm_runtime_enable(&pdev->dev);  in pwm_lpss_probe_platform()
67 	pm_runtime_disable(&pdev->dev);  in pwm_lpss_remove_platform()
81 		.name = "pwm-lpss",
89 MODULE_DESCRIPTION("PWM platform driver for Intel LPSS");
92 MODULE_ALIAS("platform:pwm-lpss");