linux/drivers/soc/ti/ti_sci_pm_domains.c
Dave Gerlach 4dd6a9973b soc: ti: ti_sci_pm_domains: Populate name for genpd
Commit b6a1d093f9 ("PM / Domains: Extend generic power domain
debugfs") now creates a debugfs directory for each genpd based on the
name of the genpd. Currently no name is given to the genpd created by
ti_sci_pm_domains driver so because of this we see a NULL pointer
dereferences when it is accessed on boot when the debugfs entry creation
is attempted.

Give the genpd a name before registering it to avoid this.

Fixes: 52835d59fc ("soc: ti: Add ti_sci_pm_domains driver")
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2017-08-18 11:59:53 +02:00

205 lines
5.7 KiB
C

/*
* 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>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#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");