2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 13:43:55 +08:00
linux-next/drivers/reset/reset-scmi.c
Sudeep Holla 61423712db reset: reset-scmi: add missing handle initialisation
scmi_reset_data->handle needs to be initialised at probe, so that it
can be later used to access scmi reset protocol APIs using the same.

Since it was tested with a module that obtained handle elsewhere,
it was missed easily. Add the missing scmi_reset_data->handle
initialisation to fix the issue.

Fixes: c8ae9c2da1 ("reset: Add support for resets provided by SCMI")
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Reported-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-09-18 13:42:44 +01:00

126 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* ARM System Control and Management Interface (ARM SCMI) reset driver
*
* Copyright (C) 2019 ARM Ltd.
*/
#include <linux/module.h>
#include <linux/of.h>
#include <linux/device.h>
#include <linux/reset-controller.h>
#include <linux/scmi_protocol.h>
/**
* struct scmi_reset_data - reset controller information structure
* @rcdev: reset controller entity
* @handle: ARM SCMI handle used for communication with system controller
*/
struct scmi_reset_data {
struct reset_controller_dev rcdev;
const struct scmi_handle *handle;
};
#define to_scmi_reset_data(p) container_of((p), struct scmi_reset_data, rcdev)
#define to_scmi_handle(p) (to_scmi_reset_data(p)->handle)
/**
* scmi_reset_assert() - assert device reset
* @rcdev: reset controller entity
* @id: ID of the reset to be asserted
*
* This function implements the reset driver op to assert a device's reset
* using the ARM SCMI protocol.
*
* Return: 0 for successful request, else a corresponding error value
*/
static int
scmi_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
{
const struct scmi_handle *handle = to_scmi_handle(rcdev);
return handle->reset_ops->assert(handle, id);
}
/**
* scmi_reset_deassert() - deassert device reset
* @rcdev: reset controller entity
* @id: ID of the reset to be deasserted
*
* This function implements the reset driver op to deassert a device's reset
* using the ARM SCMI protocol.
*
* Return: 0 for successful request, else a corresponding error value
*/
static int
scmi_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
{
const struct scmi_handle *handle = to_scmi_handle(rcdev);
return handle->reset_ops->deassert(handle, id);
}
/**
* scmi_reset_reset() - reset the device
* @rcdev: reset controller entity
* @id: ID of the reset signal to be reset(assert + deassert)
*
* This function implements the reset driver op to trigger a device's
* reset signal using the ARM SCMI protocol.
*
* Return: 0 for successful request, else a corresponding error value
*/
static int
scmi_reset_reset(struct reset_controller_dev *rcdev, unsigned long id)
{
const struct scmi_handle *handle = to_scmi_handle(rcdev);
return handle->reset_ops->reset(handle, id);
}
static const struct reset_control_ops scmi_reset_ops = {
.assert = scmi_reset_assert,
.deassert = scmi_reset_deassert,
.reset = scmi_reset_reset,
};
static int scmi_reset_probe(struct scmi_device *sdev)
{
struct scmi_reset_data *data;
struct device *dev = &sdev->dev;
struct device_node *np = dev->of_node;
const struct scmi_handle *handle = sdev->handle;
if (!handle || !handle->reset_ops)
return -ENODEV;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->rcdev.ops = &scmi_reset_ops;
data->rcdev.owner = THIS_MODULE;
data->rcdev.of_node = np;
data->rcdev.nr_resets = handle->reset_ops->num_domains_get(handle);
data->handle = handle;
return devm_reset_controller_register(dev, &data->rcdev);
}
static const struct scmi_device_id scmi_id_table[] = {
{ SCMI_PROTOCOL_RESET },
{ },
};
MODULE_DEVICE_TABLE(scmi, scmi_id_table);
static struct scmi_driver scmi_reset_driver = {
.name = "scmi-reset",
.probe = scmi_reset_probe,
.id_table = scmi_id_table,
};
module_scmi_driver(scmi_reset_driver);
MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
MODULE_DESCRIPTION("ARM SCMI reset controller driver");
MODULE_LICENSE("GPL v2");