1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * SCMI Generic power domain support. 4 * 5 * Copyright (C) 2018-2021 ARM Ltd. 6 */ 7 8 #include <linux/err.h> 9 #include <linux/io.h> 10 #include <linux/module.h> 11 #include <linux/pm_domain.h> 12 #include <linux/scmi_protocol.h> 13 14 static const struct scmi_power_proto_ops *power_ops; 15 16 struct scmi_pm_domain { 17 struct generic_pm_domain genpd; 18 const struct scmi_protocol_handle *ph; 19 const char *name; 20 u32 domain; 21 }; 22 23 #define to_scmi_pd(gpd) container_of(gpd, struct scmi_pm_domain, genpd) 24 25 static int scmi_pd_power(struct generic_pm_domain *domain, u32 state) 26 { 27 struct scmi_pm_domain *pd = to_scmi_pd(domain); 28 29 return power_ops->state_set(pd->ph, pd->domain, state); 30 } 31 32 static int scmi_pd_power_on(struct generic_pm_domain *domain) 33 { 34 return scmi_pd_power(domain, SCMI_POWER_STATE_GENERIC_ON); 35 } 36 37 static int scmi_pd_power_off(struct generic_pm_domain *domain) 38 { 39 return scmi_pd_power(domain, SCMI_POWER_STATE_GENERIC_OFF); 40 } 41 42 static int scmi_pm_domain_probe(struct scmi_device *sdev) 43 { 44 int num_domains, i; 45 struct device *dev = &sdev->dev; 46 struct device_node *np = dev->of_node; 47 struct scmi_pm_domain *scmi_pd; 48 struct genpd_onecell_data *scmi_pd_data; 49 struct generic_pm_domain **domains; 50 const struct scmi_handle *handle = sdev->handle; 51 struct scmi_protocol_handle *ph; 52 53 if (!handle) 54 return -ENODEV; 55 56 power_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_POWER, &ph); 57 if (IS_ERR(power_ops)) 58 return PTR_ERR(power_ops); 59 60 num_domains = power_ops->num_domains_get(ph); 61 if (num_domains < 0) { 62 dev_err(dev, "number of domains not found\n"); 63 return num_domains; 64 } 65 66 scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL); 67 if (!scmi_pd) 68 return -ENOMEM; 69 70 scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL); 71 if (!scmi_pd_data) 72 return -ENOMEM; 73 74 domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL); 75 if (!domains) 76 return -ENOMEM; 77 78 for (i = 0; i < num_domains; i++, scmi_pd++) { 79 u32 state; 80 81 if (power_ops->state_get(ph, i, &state)) { 82 dev_warn(dev, "failed to get state for domain %d\n", i); 83 continue; 84 } 85 86 /* 87 * Register the explicit power on request to the firmware so 88 * that it is tracked as used by OSPM agent and not 89 * accidentally turned off with OSPM's knowledge 90 */ 91 if (state == SCMI_POWER_STATE_GENERIC_ON) 92 power_ops->state_set(ph, i, state); 93 94 scmi_pd->domain = i; 95 scmi_pd->ph = ph; 96 scmi_pd->name = power_ops->name_get(ph, i); 97 scmi_pd->genpd.name = scmi_pd->name; 98 scmi_pd->genpd.power_off = scmi_pd_power_off; 99 scmi_pd->genpd.power_on = scmi_pd_power_on; 100 scmi_pd->genpd.flags = GENPD_FLAG_ACTIVE_WAKEUP; 101 102 pm_genpd_init(&scmi_pd->genpd, NULL, 103 state == SCMI_POWER_STATE_GENERIC_OFF); 104 105 domains[i] = &scmi_pd->genpd; 106 } 107 108 scmi_pd_data->domains = domains; 109 scmi_pd_data->num_domains = num_domains; 110 111 dev_set_drvdata(dev, scmi_pd_data); 112 113 return of_genpd_add_provider_onecell(np, scmi_pd_data); 114 } 115 116 static void scmi_pm_domain_remove(struct scmi_device *sdev) 117 { 118 int i; 119 struct genpd_onecell_data *scmi_pd_data; 120 struct device *dev = &sdev->dev; 121 struct device_node *np = dev->of_node; 122 123 of_genpd_del_provider(np); 124 125 scmi_pd_data = dev_get_drvdata(dev); 126 for (i = 0; i < scmi_pd_data->num_domains; i++) { 127 if (!scmi_pd_data->domains[i]) 128 continue; 129 pm_genpd_remove(scmi_pd_data->domains[i]); 130 } 131 } 132 133 static const struct scmi_device_id scmi_id_table[] = { 134 { SCMI_PROTOCOL_POWER, "genpd" }, 135 { }, 136 }; 137 MODULE_DEVICE_TABLE(scmi, scmi_id_table); 138 139 static struct scmi_driver scmi_power_domain_driver = { 140 .name = "scmi-power-domain", 141 .probe = scmi_pm_domain_probe, 142 .remove = scmi_pm_domain_remove, 143 .id_table = scmi_id_table, 144 }; 145 module_scmi_driver(scmi_power_domain_driver); 146 147 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); 148 MODULE_DESCRIPTION("ARM SCMI power domain driver"); 149 MODULE_LICENSE("GPL v2"); 150