1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Intel Low Power Subsystem PWM controller driver 4 * 5 * Copyright (C) 2014, Intel Corporation 6 * 7 * Derived from the original pwm-lpss.c 8 */ 9 10 #include <linux/acpi.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/platform_device.h> 14 #include <linux/pm_runtime.h> 15 16 #include "pwm-lpss.h" 17 18 /* BayTrail */ 19 static const struct pwm_lpss_boardinfo pwm_lpss_byt_info = { 20 .clk_rate = 25000000, 21 .npwm = 1, 22 .base_unit_bits = 16, 23 }; 24 25 /* Braswell */ 26 static const struct pwm_lpss_boardinfo pwm_lpss_bsw_info = { 27 .clk_rate = 19200000, 28 .npwm = 1, 29 .base_unit_bits = 16, 30 .other_devices_aml_touches_pwm_regs = true, 31 }; 32 33 /* Broxton */ 34 static const struct pwm_lpss_boardinfo pwm_lpss_bxt_info = { 35 .clk_rate = 19200000, 36 .npwm = 4, 37 .base_unit_bits = 22, 38 .bypass = true, 39 }; 40 41 static int pwm_lpss_probe_platform(struct platform_device *pdev) 42 { 43 const struct pwm_lpss_boardinfo *info; 44 const struct acpi_device_id *id; 45 struct pwm_lpss_chip *lpwm; 46 struct resource *r; 47 48 id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); 49 if (!id) 50 return -ENODEV; 51 52 info = (const struct pwm_lpss_boardinfo *)id->driver_data; 53 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 54 55 lpwm = pwm_lpss_probe(&pdev->dev, r, info); 56 if (IS_ERR(lpwm)) 57 return PTR_ERR(lpwm); 58 59 platform_set_drvdata(pdev, lpwm); 60 61 dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_SMART_PREPARE); 62 pm_runtime_set_active(&pdev->dev); 63 pm_runtime_enable(&pdev->dev); 64 65 return 0; 66 } 67 68 static int pwm_lpss_remove_platform(struct platform_device *pdev) 69 { 70 struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev); 71 72 pm_runtime_disable(&pdev->dev); 73 return pwm_lpss_remove(lpwm); 74 } 75 76 static int pwm_lpss_prepare(struct device *dev) 77 { 78 struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev); 79 80 /* 81 * If other device's AML code touches the PWM regs on suspend/resume 82 * force runtime-resume the PWM controller to allow this. 83 */ 84 if (lpwm->info->other_devices_aml_touches_pwm_regs) 85 return 0; /* Force runtime-resume */ 86 87 return 1; /* If runtime-suspended leave as is */ 88 } 89 90 static const struct dev_pm_ops pwm_lpss_platform_pm_ops = { 91 .prepare = pwm_lpss_prepare, 92 SET_SYSTEM_SLEEP_PM_OPS(pwm_lpss_suspend, pwm_lpss_resume) 93 }; 94 95 static const struct acpi_device_id pwm_lpss_acpi_match[] = { 96 { "80860F09", (unsigned long)&pwm_lpss_byt_info }, 97 { "80862288", (unsigned long)&pwm_lpss_bsw_info }, 98 { "80862289", (unsigned long)&pwm_lpss_bsw_info }, 99 { "80865AC8", (unsigned long)&pwm_lpss_bxt_info }, 100 { }, 101 }; 102 MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match); 103 104 static struct platform_driver pwm_lpss_driver_platform = { 105 .driver = { 106 .name = "pwm-lpss", 107 .acpi_match_table = pwm_lpss_acpi_match, 108 .pm = &pwm_lpss_platform_pm_ops, 109 }, 110 .probe = pwm_lpss_probe_platform, 111 .remove = pwm_lpss_remove_platform, 112 }; 113 module_platform_driver(pwm_lpss_driver_platform); 114 115 MODULE_DESCRIPTION("PWM platform driver for Intel LPSS"); 116 MODULE_LICENSE("GPL v2"); 117 MODULE_ALIAS("platform:pwm-lpss"); 118