1 /* 2 * Intel Low Power Subsystem PWM controller driver 3 * 4 * Copyright (C) 2014, Intel Corporation 5 * 6 * Derived from the original pwm-lpss.c 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/acpi.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/platform_device.h> 17 #include <linux/pm_runtime.h> 18 19 #include "pwm-lpss.h" 20 21 /* BayTrail */ 22 static const struct pwm_lpss_boardinfo pwm_lpss_byt_info = { 23 .clk_rate = 25000000, 24 .npwm = 1, 25 .base_unit_bits = 16, 26 }; 27 28 /* Braswell */ 29 static const struct pwm_lpss_boardinfo pwm_lpss_bsw_info = { 30 .clk_rate = 19200000, 31 .npwm = 1, 32 .base_unit_bits = 16, 33 .other_devices_aml_touches_pwm_regs = true, 34 }; 35 36 /* Broxton */ 37 static const struct pwm_lpss_boardinfo pwm_lpss_bxt_info = { 38 .clk_rate = 19200000, 39 .npwm = 4, 40 .base_unit_bits = 22, 41 .bypass = true, 42 }; 43 44 static int pwm_lpss_probe_platform(struct platform_device *pdev) 45 { 46 const struct pwm_lpss_boardinfo *info; 47 const struct acpi_device_id *id; 48 struct pwm_lpss_chip *lpwm; 49 struct resource *r; 50 51 id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); 52 if (!id) 53 return -ENODEV; 54 55 info = (const struct pwm_lpss_boardinfo *)id->driver_data; 56 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 57 58 lpwm = pwm_lpss_probe(&pdev->dev, r, info); 59 if (IS_ERR(lpwm)) 60 return PTR_ERR(lpwm); 61 62 platform_set_drvdata(pdev, lpwm); 63 64 dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_SMART_PREPARE); 65 pm_runtime_set_active(&pdev->dev); 66 pm_runtime_enable(&pdev->dev); 67 68 return 0; 69 } 70 71 static int pwm_lpss_remove_platform(struct platform_device *pdev) 72 { 73 struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev); 74 75 pm_runtime_disable(&pdev->dev); 76 return pwm_lpss_remove(lpwm); 77 } 78 79 static int pwm_lpss_prepare(struct device *dev) 80 { 81 struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev); 82 83 /* 84 * If other device's AML code touches the PWM regs on suspend/resume 85 * force runtime-resume the PWM controller to allow this. 86 */ 87 if (lpwm->info->other_devices_aml_touches_pwm_regs) 88 return 0; /* Force runtime-resume */ 89 90 return 1; /* If runtime-suspended leave as is */ 91 } 92 93 static const struct dev_pm_ops pwm_lpss_platform_pm_ops = { 94 .prepare = pwm_lpss_prepare, 95 SET_SYSTEM_SLEEP_PM_OPS(pwm_lpss_suspend, pwm_lpss_resume) 96 }; 97 98 static const struct acpi_device_id pwm_lpss_acpi_match[] = { 99 { "80860F09", (unsigned long)&pwm_lpss_byt_info }, 100 { "80862288", (unsigned long)&pwm_lpss_bsw_info }, 101 { "80862289", (unsigned long)&pwm_lpss_bsw_info }, 102 { "80865AC8", (unsigned long)&pwm_lpss_bxt_info }, 103 { }, 104 }; 105 MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match); 106 107 static struct platform_driver pwm_lpss_driver_platform = { 108 .driver = { 109 .name = "pwm-lpss", 110 .acpi_match_table = pwm_lpss_acpi_match, 111 .pm = &pwm_lpss_platform_pm_ops, 112 }, 113 .probe = pwm_lpss_probe_platform, 114 .remove = pwm_lpss_remove_platform, 115 }; 116 module_platform_driver(pwm_lpss_driver_platform); 117 118 MODULE_DESCRIPTION("PWM platform driver for Intel LPSS"); 119 MODULE_LICENSE("GPL v2"); 120 MODULE_ALIAS("platform:pwm-lpss"); 121