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1// SPDX-License-Identifier: GPL-2.02/*3 * DesignWare PWM Controller driver (PCI part)4 *5 * Copyright (C) 2018-2020 Intel Corporation6 *7 * Author: Felipe Balbi (Intel)8 * Author: Jarkko Nikula <jarkko.nikula@linux.intel.com>9 * Author: Raymond Tan <raymond.tan@intel.com>10 *11 * Limitations:12 * - The hardware cannot generate a 0 % or 100 % duty cycle. Both high and low13 * periods are one or more input clock periods long.14 */15 16#define DEFAULT_MOUDLE_NAMESPACE dwc_pwm17 18#include <linux/bitops.h>19#include <linux/export.h>20#include <linux/kernel.h>21#include <linux/module.h>22#include <linux/pci.h>23#include <linux/pm_runtime.h>24#include <linux/pwm.h>25 26#include "pwm-dwc.h"27 28/* Elkhart Lake */29static const struct dwc_pwm_info ehl_pwm_info = {30 .nr = 2,31 .size = 0x1000,32};33 34static int dwc_pwm_init_one(struct device *dev, struct dwc_pwm_drvdata *ddata, unsigned int idx)35{36 struct pwm_chip *chip;37 struct dwc_pwm *dwc;38 int ret;39 40 chip = dwc_pwm_alloc(dev);41 if (IS_ERR(chip))42 return PTR_ERR(chip);43 44 dwc = to_dwc_pwm(chip);45 dwc->base = ddata->io_base + (ddata->info->size * idx);46 47 ret = devm_pwmchip_add(dev, chip);48 if (ret)49 return ret;50 51 ddata->chips[idx] = chip;52 return 0;53}54 55static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)56{57 const struct dwc_pwm_info *info;58 struct device *dev = &pci->dev;59 struct dwc_pwm_drvdata *ddata;60 unsigned int idx;61 int ret;62 63 ret = pcim_enable_device(pci);64 if (ret)65 return dev_err_probe(dev, ret, "Failed to enable device\n");66 67 pci_set_master(pci);68 69 ret = pcim_iomap_regions(pci, BIT(0), pci_name(pci));70 if (ret)71 return dev_err_probe(dev, ret, "Failed to iomap PCI BAR\n");72 73 info = (const struct dwc_pwm_info *)id->driver_data;74 ddata = devm_kzalloc(dev, struct_size(ddata, chips, info->nr), GFP_KERNEL);75 if (!ddata)76 return -ENOMEM;77 78 /*79 * No need to check for pcim_iomap_table() failure,80 * pcim_iomap_regions() already does it for us.81 */82 ddata->io_base = pcim_iomap_table(pci)[0];83 ddata->info = info;84 85 for (idx = 0; idx < ddata->info->nr; idx++) {86 ret = dwc_pwm_init_one(dev, ddata, idx);87 if (ret)88 return ret;89 }90 91 dev_set_drvdata(dev, ddata);92 93 pm_runtime_put(dev);94 pm_runtime_allow(dev);95 96 return 0;97}98 99static void dwc_pwm_remove(struct pci_dev *pci)100{101 pm_runtime_forbid(&pci->dev);102 pm_runtime_get_noresume(&pci->dev);103}104 105static int dwc_pwm_suspend(struct device *dev)106{107 struct dwc_pwm_drvdata *ddata = dev_get_drvdata(dev);108 unsigned int idx;109 110 for (idx = 0; idx < ddata->info->nr; idx++) {111 struct pwm_chip *chip = ddata->chips[idx];112 struct dwc_pwm *dwc = to_dwc_pwm(chip);113 unsigned int i;114 115 for (i = 0; i < DWC_TIMERS_TOTAL; i++) {116 if (chip->pwms[i].state.enabled) {117 dev_err(dev, "PWM %u in use by consumer (%s)\n",118 i, chip->pwms[i].label);119 return -EBUSY;120 }121 dwc->ctx[i].cnt = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(i));122 dwc->ctx[i].cnt2 = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(i));123 dwc->ctx[i].ctrl = dwc_pwm_readl(dwc, DWC_TIM_CTRL(i));124 }125 }126 127 return 0;128}129 130static int dwc_pwm_resume(struct device *dev)131{132 struct dwc_pwm_drvdata *ddata = dev_get_drvdata(dev);133 unsigned int idx;134 135 for (idx = 0; idx < ddata->info->nr; idx++) {136 struct pwm_chip *chip = ddata->chips[idx];137 struct dwc_pwm *dwc = to_dwc_pwm(chip);138 unsigned int i;139 140 for (i = 0; i < DWC_TIMERS_TOTAL; i++) {141 dwc_pwm_writel(dwc, dwc->ctx[i].cnt, DWC_TIM_LD_CNT(i));142 dwc_pwm_writel(dwc, dwc->ctx[i].cnt2, DWC_TIM_LD_CNT2(i));143 dwc_pwm_writel(dwc, dwc->ctx[i].ctrl, DWC_TIM_CTRL(i));144 }145 }146 147 return 0;148}149 150static DEFINE_SIMPLE_DEV_PM_OPS(dwc_pwm_pm_ops, dwc_pwm_suspend, dwc_pwm_resume);151 152static const struct pci_device_id dwc_pwm_id_table[] = {153 { PCI_VDEVICE(INTEL, 0x4bb7), (kernel_ulong_t)&ehl_pwm_info },154 { } /* Terminating Entry */155};156MODULE_DEVICE_TABLE(pci, dwc_pwm_id_table);157 158static struct pci_driver dwc_pwm_driver = {159 .name = "pwm-dwc",160 .probe = dwc_pwm_probe,161 .remove = dwc_pwm_remove,162 .id_table = dwc_pwm_id_table,163 .driver = {164 .pm = pm_sleep_ptr(&dwc_pwm_pm_ops),165 },166};167 168module_pci_driver(dwc_pwm_driver);169 170MODULE_AUTHOR("Felipe Balbi (Intel)");171MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");172MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");173MODULE_DESCRIPTION("DesignWare PWM Controller");174MODULE_LICENSE("GPL");175