diff options
Diffstat (limited to 'drivers/pmdomain/arm/scmi_pm_domain.c')
| -rw-r--r-- | drivers/pmdomain/arm/scmi_pm_domain.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/pmdomain/arm/scmi_pm_domain.c b/drivers/pmdomain/arm/scmi_pm_domain.c new file mode 100644 index 0000000000..0e05a79de8 --- /dev/null +++ b/drivers/pmdomain/arm/scmi_pm_domain.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SCMI Generic power domain support. + * + * Copyright (C) 2018-2021 ARM Ltd. + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/pm_domain.h> +#include <linux/scmi_protocol.h> + +static const struct scmi_power_proto_ops *power_ops; + +struct scmi_pm_domain { + struct generic_pm_domain genpd; + const struct scmi_protocol_handle *ph; + const char *name; + u32 domain; +}; + +#define to_scmi_pd(gpd) container_of(gpd, struct scmi_pm_domain, genpd) + +static int scmi_pd_power(struct generic_pm_domain *domain, bool power_on) +{ + int ret; + u32 state, ret_state; + struct scmi_pm_domain *pd = to_scmi_pd(domain); + + if (power_on) + state = SCMI_POWER_STATE_GENERIC_ON; + else + state = SCMI_POWER_STATE_GENERIC_OFF; + + ret = power_ops->state_set(pd->ph, pd->domain, state); + if (!ret) + ret = power_ops->state_get(pd->ph, pd->domain, &ret_state); + if (!ret && state != ret_state) + return -EIO; + + return ret; +} + +static int scmi_pd_power_on(struct generic_pm_domain *domain) +{ + return scmi_pd_power(domain, true); +} + +static int scmi_pd_power_off(struct generic_pm_domain *domain) +{ + return scmi_pd_power(domain, false); +} + +static int scmi_pm_domain_probe(struct scmi_device *sdev) +{ + int num_domains, i; + struct device *dev = &sdev->dev; + struct device_node *np = dev->of_node; + struct scmi_pm_domain *scmi_pd; + struct genpd_onecell_data *scmi_pd_data; + struct generic_pm_domain **domains; + const struct scmi_handle *handle = sdev->handle; + struct scmi_protocol_handle *ph; + + if (!handle) + return -ENODEV; + + power_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_POWER, &ph); + if (IS_ERR(power_ops)) + return PTR_ERR(power_ops); + + num_domains = power_ops->num_domains_get(ph); + if (num_domains < 0) { + dev_err(dev, "number of domains not found\n"); + return num_domains; + } + + scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL); + if (!scmi_pd) + return -ENOMEM; + + scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL); + if (!scmi_pd_data) + return -ENOMEM; + + domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL); + if (!domains) + return -ENOMEM; + + for (i = 0; i < num_domains; i++, scmi_pd++) { + u32 state; + + if (power_ops->state_get(ph, i, &state)) { + dev_warn(dev, "failed to get state for domain %d\n", i); + continue; + } + + scmi_pd->domain = i; + scmi_pd->ph = ph; + scmi_pd->name = power_ops->name_get(ph, i); + scmi_pd->genpd.name = scmi_pd->name; + scmi_pd->genpd.power_off = scmi_pd_power_off; + scmi_pd->genpd.power_on = scmi_pd_power_on; + + pm_genpd_init(&scmi_pd->genpd, NULL, + state == SCMI_POWER_STATE_GENERIC_OFF); + + domains[i] = &scmi_pd->genpd; + } + + scmi_pd_data->domains = domains; + scmi_pd_data->num_domains = num_domains; + + dev_set_drvdata(dev, scmi_pd_data); + + return of_genpd_add_provider_onecell(np, scmi_pd_data); +} + +static void scmi_pm_domain_remove(struct scmi_device *sdev) +{ + int i; + struct genpd_onecell_data *scmi_pd_data; + struct device *dev = &sdev->dev; + struct device_node *np = dev->of_node; + + of_genpd_del_provider(np); + + scmi_pd_data = dev_get_drvdata(dev); + for (i = 0; i < scmi_pd_data->num_domains; i++) { + if (!scmi_pd_data->domains[i]) + continue; + pm_genpd_remove(scmi_pd_data->domains[i]); + } +} + +static const struct scmi_device_id scmi_id_table[] = { + { SCMI_PROTOCOL_POWER, "genpd" }, + { }, +}; +MODULE_DEVICE_TABLE(scmi, scmi_id_table); + +static struct scmi_driver scmi_power_domain_driver = { + .name = "scmi-power-domain", + .probe = scmi_pm_domain_probe, + .remove = scmi_pm_domain_remove, + .id_table = scmi_id_table, +}; +module_scmi_driver(scmi_power_domain_driver); + +MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); +MODULE_DESCRIPTION("ARM SCMI power domain driver"); +MODULE_LICENSE("GPL v2"); |