| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * TI SCI Generic Power Domain Driver |
| * |
| * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/ |
| * J Keerthy <j-keerthy@ti.com> |
| * Dave Gerlach <d-gerlach@ti.com> |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_domain.h> |
| #include <linux/slab.h> |
| #include <linux/soc/ti/ti_sci_protocol.h> |
| |
| /** |
| * struct ti_sci_genpd_dev_data: holds data needed for every device attached |
| * to this genpd |
| * @idx: index of the device that identifies it with the system |
| * control processor. |
| */ |
| struct ti_sci_genpd_dev_data { |
| int idx; |
| }; |
| |
| /** |
| * struct ti_sci_pm_domain: TI specific data needed for power domain |
| * @ti_sci: handle to TI SCI protocol driver that provides ops to |
| * communicate with system control processor. |
| * @dev: pointer to dev for the driver for devm allocs |
| * @pd: generic_pm_domain for use with the genpd framework |
| */ |
| struct ti_sci_pm_domain { |
| const struct ti_sci_handle *ti_sci; |
| struct device *dev; |
| struct generic_pm_domain pd; |
| }; |
| |
| #define genpd_to_ti_sci_pd(gpd) container_of(gpd, struct ti_sci_pm_domain, pd) |
| |
| /** |
| * ti_sci_dev_id(): get prepopulated ti_sci id from struct dev |
| * @dev: pointer to device associated with this genpd |
| * |
| * Returns device_id stored from ti,sci_id property |
| */ |
| static int ti_sci_dev_id(struct device *dev) |
| { |
| struct generic_pm_domain_data *genpd_data = dev_gpd_data(dev); |
| struct ti_sci_genpd_dev_data *sci_dev_data = genpd_data->data; |
| |
| return sci_dev_data->idx; |
| } |
| |
| /** |
| * ti_sci_dev_to_sci_handle(): get pointer to ti_sci_handle |
| * @dev: pointer to device associated with this genpd |
| * |
| * Returns ti_sci_handle to be used to communicate with system |
| * control processor. |
| */ |
| static const struct ti_sci_handle *ti_sci_dev_to_sci_handle(struct device *dev) |
| { |
| struct generic_pm_domain *pd = pd_to_genpd(dev->pm_domain); |
| struct ti_sci_pm_domain *ti_sci_genpd = genpd_to_ti_sci_pd(pd); |
| |
| return ti_sci_genpd->ti_sci; |
| } |
| |
| /** |
| * ti_sci_dev_start(): genpd device start hook called to turn device on |
| * @dev: pointer to device associated with this genpd to be powered on |
| */ |
| static int ti_sci_dev_start(struct device *dev) |
| { |
| const struct ti_sci_handle *ti_sci = ti_sci_dev_to_sci_handle(dev); |
| int idx = ti_sci_dev_id(dev); |
| |
| return ti_sci->ops.dev_ops.get_device(ti_sci, idx); |
| } |
| |
| /** |
| * ti_sci_dev_stop(): genpd device stop hook called to turn device off |
| * @dev: pointer to device associated with this genpd to be powered off |
| */ |
| static int ti_sci_dev_stop(struct device *dev) |
| { |
| const struct ti_sci_handle *ti_sci = ti_sci_dev_to_sci_handle(dev); |
| int idx = ti_sci_dev_id(dev); |
| |
| return ti_sci->ops.dev_ops.put_device(ti_sci, idx); |
| } |
| |
| static int ti_sci_pd_attach_dev(struct generic_pm_domain *domain, |
| struct device *dev) |
| { |
| struct device_node *np = dev->of_node; |
| struct of_phandle_args pd_args; |
| struct ti_sci_pm_domain *ti_sci_genpd = genpd_to_ti_sci_pd(domain); |
| const struct ti_sci_handle *ti_sci = ti_sci_genpd->ti_sci; |
| struct ti_sci_genpd_dev_data *sci_dev_data; |
| struct generic_pm_domain_data *genpd_data; |
| int idx, ret = 0; |
| |
| ret = of_parse_phandle_with_args(np, "power-domains", |
| "#power-domain-cells", 0, &pd_args); |
| if (ret < 0) |
| return ret; |
| |
| if (pd_args.args_count != 1) |
| return -EINVAL; |
| |
| idx = pd_args.args[0]; |
| |
| /* |
| * Check the validity of the requested idx, if the index is not valid |
| * the PMMC will return a NAK here and we will not allocate it. |
| */ |
| ret = ti_sci->ops.dev_ops.is_valid(ti_sci, idx); |
| if (ret) |
| return -EINVAL; |
| |
| sci_dev_data = kzalloc(sizeof(*sci_dev_data), GFP_KERNEL); |
| if (!sci_dev_data) |
| return -ENOMEM; |
| |
| sci_dev_data->idx = idx; |
| |
| genpd_data = dev_gpd_data(dev); |
| genpd_data->data = sci_dev_data; |
| |
| return 0; |
| } |
| |
| static void ti_sci_pd_detach_dev(struct generic_pm_domain *domain, |
| struct device *dev) |
| { |
| struct generic_pm_domain_data *genpd_data = dev_gpd_data(dev); |
| struct ti_sci_genpd_dev_data *sci_dev_data = genpd_data->data; |
| |
| kfree(sci_dev_data); |
| genpd_data->data = NULL; |
| } |
| |
| static const struct of_device_id ti_sci_pm_domain_matches[] = { |
| { .compatible = "ti,sci-pm-domain", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, ti_sci_pm_domain_matches); |
| |
| static int ti_sci_pm_domain_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct device_node *np = dev->of_node; |
| struct ti_sci_pm_domain *ti_sci_pd; |
| int ret; |
| |
| ti_sci_pd = devm_kzalloc(dev, sizeof(*ti_sci_pd), GFP_KERNEL); |
| if (!ti_sci_pd) |
| return -ENOMEM; |
| |
| ti_sci_pd->ti_sci = devm_ti_sci_get_handle(dev); |
| if (IS_ERR(ti_sci_pd->ti_sci)) |
| return PTR_ERR(ti_sci_pd->ti_sci); |
| |
| ti_sci_pd->dev = dev; |
| |
| ti_sci_pd->pd.name = "ti_sci_pd"; |
| |
| ti_sci_pd->pd.attach_dev = ti_sci_pd_attach_dev; |
| ti_sci_pd->pd.detach_dev = ti_sci_pd_detach_dev; |
| |
| ti_sci_pd->pd.dev_ops.start = ti_sci_dev_start; |
| ti_sci_pd->pd.dev_ops.stop = ti_sci_dev_stop; |
| |
| pm_genpd_init(&ti_sci_pd->pd, NULL, true); |
| |
| ret = of_genpd_add_provider_simple(np, &ti_sci_pd->pd); |
| |
| return ret; |
| } |
| |
| static struct platform_driver ti_sci_pm_domains_driver = { |
| .probe = ti_sci_pm_domain_probe, |
| .driver = { |
| .name = "ti_sci_pm_domains", |
| .of_match_table = ti_sci_pm_domain_matches, |
| }, |
| }; |
| module_platform_driver(ti_sci_pm_domains_driver); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver"); |
| MODULE_AUTHOR("Dave Gerlach"); |