LXR linux/drivers/pwm/pwm-lpss-platform.c

   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 */
  19static 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 */
  26static 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 */
  34static 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
  41static 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
  68static 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
  76static 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
  90static 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
  95static 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};
 102MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
 103
 104static 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};
 113module_platform_driver(pwm_lpss_driver_platform);
 114
 115MODULE_DESCRIPTION("PWM platform driver for Intel LPSS");
 116MODULE_LICENSE("GPL v2");
 117MODULE_ALIAS("platform:pwm-lpss");
 118