1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2024 Linaro Ltd. 4 */ 5 6 #include <linux/device.h> 7 #include <linux/mod_devicetable.h> 8 #include <linux/module.h> 9 #include <linux/pci-pwrctrl.h> 10 #include <linux/platform_device.h> 11 #include <linux/property.h> 12 #include <linux/pwrseq/consumer.h> 13 #include <linux/slab.h> 14 #include <linux/types.h> 15 16 struct pci_pwrctrl_pwrseq_data { 17 struct pci_pwrctrl ctx; 18 struct pwrseq_desc *pwrseq; 19 }; 20 21 struct pci_pwrctrl_pwrseq_pdata { 22 const char *target; 23 /* 24 * Called before doing anything else to perform device-specific 25 * verification between requesting the power sequencing handle. 26 */ 27 int (*validate_device)(struct device *dev); 28 }; 29 30 static int pci_pwrctrl_pwrseq_qcm_wcn_validate_device(struct device *dev) 31 { 32 /* 33 * Old device trees for some platforms already define wifi nodes for 34 * the WCN family of chips since before power sequencing was added 35 * upstream. 36 * 37 * These nodes don't consume the regulator outputs from the PMU, and 38 * if we allow this driver to bind to one of such "incomplete" nodes, 39 * we'll see a kernel log error about the indefinite probe deferral. 40 * 41 * Check the existence of the regulator supply that exists on all 42 * WCN models before moving forward. 43 */ 44 if (!device_property_present(dev, "vddaon-supply")) 45 return -ENODEV; 46 47 return 0; 48 } 49 50 static const struct pci_pwrctrl_pwrseq_pdata pci_pwrctrl_pwrseq_qcom_wcn_pdata = { 51 .target = "wlan", 52 .validate_device = pci_pwrctrl_pwrseq_qcm_wcn_validate_device, 53 }; 54 55 static void devm_pci_pwrctrl_pwrseq_power_off(void *data) 56 { 57 struct pwrseq_desc *pwrseq = data; 58 59 pwrseq_power_off(pwrseq); 60 } 61 62 static int pci_pwrctrl_pwrseq_probe(struct platform_device *pdev) 63 { 64 const struct pci_pwrctrl_pwrseq_pdata *pdata; 65 struct pci_pwrctrl_pwrseq_data *data; 66 struct device *dev = &pdev->dev; 67 int ret; 68 69 pdata = device_get_match_data(dev); 70 if (!pdata || !pdata->target) 71 return -EINVAL; 72 73 if (pdata->validate_device) { 74 ret = pdata->validate_device(dev); 75 if (ret) 76 return ret; 77 } 78 79 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 80 if (!data) 81 return -ENOMEM; 82 83 data->pwrseq = devm_pwrseq_get(dev, pdata->target); 84 if (IS_ERR(data->pwrseq)) 85 return dev_err_probe(dev, PTR_ERR(data->pwrseq), 86 "Failed to get the power sequencer\n"); 87 88 ret = pwrseq_power_on(data->pwrseq); 89 if (ret) 90 return dev_err_probe(dev, ret, 91 "Failed to power-on the device\n"); 92 93 ret = devm_add_action_or_reset(dev, devm_pci_pwrctrl_pwrseq_power_off, 94 data->pwrseq); 95 if (ret) 96 return ret; 97 98 pci_pwrctrl_init(&data->ctx, dev); 99 100 ret = devm_pci_pwrctrl_device_set_ready(dev, &data->ctx); 101 if (ret) 102 return dev_err_probe(dev, ret, 103 "Failed to register the pwrctrl wrapper\n"); 104 105 return 0; 106 } 107 108 static const struct of_device_id pci_pwrctrl_pwrseq_of_match[] = { 109 { 110 /* ATH11K in QCA6390 package. */ 111 .compatible = "pci17cb,1101", 112 .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, 113 }, 114 { 115 /* ATH11K in WCN6855 package. */ 116 .compatible = "pci17cb,1103", 117 .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, 118 }, 119 { 120 /* ATH12K in WCN7850 package. */ 121 .compatible = "pci17cb,1107", 122 .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, 123 }, 124 { } 125 }; 126 MODULE_DEVICE_TABLE(of, pci_pwrctrl_pwrseq_of_match); 127 128 static struct platform_driver pci_pwrctrl_pwrseq_driver = { 129 .driver = { 130 .name = "pci-pwrctrl-pwrseq", 131 .of_match_table = pci_pwrctrl_pwrseq_of_match, 132 }, 133 .probe = pci_pwrctrl_pwrseq_probe, 134 }; 135 module_platform_driver(pci_pwrctrl_pwrseq_driver); 136 137 MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>"); 138 MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices"); 139 MODULE_LICENSE("GPL"); 140