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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * dptf_pch_fivr: DPTF PCH FIVR Participant driver4 * Copyright (c) 2020, Intel Corporation.5 */6 7#include <linux/acpi.h>8#include <linux/kernel.h>9#include <linux/module.h>10#include <linux/platform_device.h>11 12struct pch_fivr_resp {13 u64 status;14 u64 result;15};16 17static int pch_fivr_read(acpi_handle handle, char *method, struct pch_fivr_resp *fivr_resp)18{19 struct acpi_buffer resp = { sizeof(struct pch_fivr_resp), fivr_resp};20 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };21 struct acpi_buffer format = { sizeof("NN"), "NN" };22 union acpi_object *obj;23 acpi_status status;24 int ret = -EFAULT;25 26 status = acpi_evaluate_object(handle, method, NULL, &buffer);27 if (ACPI_FAILURE(status))28 return ret;29 30 obj = buffer.pointer;31 if (!obj || obj->type != ACPI_TYPE_PACKAGE)32 goto release_buffer;33 34 status = acpi_extract_package(obj, &format, &resp);35 if (ACPI_FAILURE(status))36 goto release_buffer;37 38 if (fivr_resp->status)39 goto release_buffer;40 41 ret = 0;42 43release_buffer:44 kfree(buffer.pointer);45 return ret;46}47 48/*49 * Presentation of attributes which are defined for INTC10xx50 * They are:51 * freq_mhz_low_clock : Set PCH FIVR switching freq for52 * FIVR clock 19.2MHz and 24MHz53 * freq_mhz_high_clock : Set PCH FIVR switching freq for54 * FIVR clock 38.4MHz55 */56#define PCH_FIVR_SHOW(name, method) \57static ssize_t name##_show(struct device *dev,\58 struct device_attribute *attr,\59 char *buf)\60{\61 struct acpi_device *acpi_dev = dev_get_drvdata(dev);\62 struct pch_fivr_resp fivr_resp;\63 int status;\64\65 status = pch_fivr_read(acpi_dev->handle, #method, &fivr_resp);\66 if (status)\67 return status;\68\69 return sprintf(buf, "%llu\n", fivr_resp.result);\70}71 72#define PCH_FIVR_STORE(name, method) \73static ssize_t name##_store(struct device *dev,\74 struct device_attribute *attr,\75 const char *buf, size_t count)\76{\77 struct acpi_device *acpi_dev = dev_get_drvdata(dev);\78 acpi_status status;\79 u32 val;\80\81 if (kstrtouint(buf, 0, &val) < 0)\82 return -EINVAL;\83\84 status = acpi_execute_simple_method(acpi_dev->handle, #method, val);\85 if (ACPI_SUCCESS(status))\86 return count;\87\88 return -EINVAL;\89}90 91PCH_FIVR_SHOW(freq_mhz_low_clock, GFC0)92PCH_FIVR_SHOW(freq_mhz_high_clock, GFC1)93PCH_FIVR_SHOW(ssc_clock_info, GEMI)94PCH_FIVR_SHOW(fivr_switching_freq_mhz, GFCS)95PCH_FIVR_SHOW(fivr_switching_fault_status, GFFS)96PCH_FIVR_STORE(freq_mhz_low_clock, RFC0)97PCH_FIVR_STORE(freq_mhz_high_clock, RFC1)98 99static DEVICE_ATTR_RW(freq_mhz_low_clock);100static DEVICE_ATTR_RW(freq_mhz_high_clock);101static DEVICE_ATTR_RO(ssc_clock_info);102static DEVICE_ATTR_RO(fivr_switching_freq_mhz);103static DEVICE_ATTR_RO(fivr_switching_fault_status);104 105static struct attribute *fivr_attrs[] = {106 &dev_attr_freq_mhz_low_clock.attr,107 &dev_attr_freq_mhz_high_clock.attr,108 &dev_attr_ssc_clock_info.attr,109 &dev_attr_fivr_switching_freq_mhz.attr,110 &dev_attr_fivr_switching_fault_status.attr,111 NULL112};113 114static const struct attribute_group pch_fivr_attribute_group = {115 .attrs = fivr_attrs,116 .name = "pch_fivr_switch_frequency"117};118 119static int pch_fivr_add(struct platform_device *pdev)120{121 struct acpi_device *acpi_dev;122 unsigned long long ptype;123 acpi_status status;124 int result;125 126 acpi_dev = ACPI_COMPANION(&(pdev->dev));127 if (!acpi_dev)128 return -ENODEV;129 130 status = acpi_evaluate_integer(acpi_dev->handle, "PTYP", NULL, &ptype);131 if (ACPI_FAILURE(status) || ptype != 0x05)132 return -ENODEV;133 134 result = sysfs_create_group(&pdev->dev.kobj,135 &pch_fivr_attribute_group);136 if (result)137 return result;138 139 platform_set_drvdata(pdev, acpi_dev);140 141 return 0;142}143 144static void pch_fivr_remove(struct platform_device *pdev)145{146 sysfs_remove_group(&pdev->dev.kobj, &pch_fivr_attribute_group);147}148 149static const struct acpi_device_id pch_fivr_device_ids[] = {150 {"INTC1045", 0},151 {"INTC1049", 0},152 {"INTC1064", 0},153 {"INTC106B", 0},154 {"INTC10A3", 0},155 {"", 0},156};157MODULE_DEVICE_TABLE(acpi, pch_fivr_device_ids);158 159static struct platform_driver pch_fivr_driver = {160 .probe = pch_fivr_add,161 .remove_new = pch_fivr_remove,162 .driver = {163 .name = "dptf_pch_fivr",164 .acpi_match_table = pch_fivr_device_ids,165 },166};167 168module_platform_driver(pch_fivr_driver);169 170MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");171MODULE_LICENSE("GPL v2");172MODULE_DESCRIPTION("ACPI DPTF PCH FIVR driver");173