linux/drivers/spmi/spmi.c

586 lines
15 KiB
C

/*
* Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only 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/kernel.h>
#include <linux/errno.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/spmi.h>
#include <linux/pm_runtime.h>
#include <dt-bindings/spmi/spmi.h>
#define CREATE_TRACE_POINTS
#include <trace/events/spmi.h>
static DEFINE_IDA(ctrl_ida);
static void spmi_dev_release(struct device *dev)
{
struct spmi_device *sdev = to_spmi_device(dev);
kfree(sdev);
}
static const struct device_type spmi_dev_type = {
.release = spmi_dev_release,
};
static void spmi_ctrl_release(struct device *dev)
{
struct spmi_controller *ctrl = to_spmi_controller(dev);
ida_simple_remove(&ctrl_ida, ctrl->nr);
kfree(ctrl);
}
static const struct device_type spmi_ctrl_type = {
.release = spmi_ctrl_release,
};
static int spmi_device_match(struct device *dev, struct device_driver *drv)
{
if (of_driver_match_device(dev, drv))
return 1;
if (drv->name)
return strncmp(dev_name(dev), drv->name,
SPMI_NAME_SIZE) == 0;
return 0;
}
/**
* spmi_device_add() - add a device previously constructed via spmi_device_alloc()
* @sdev: spmi_device to be added
*/
int spmi_device_add(struct spmi_device *sdev)
{
struct spmi_controller *ctrl = sdev->ctrl;
int err;
dev_set_name(&sdev->dev, "%d-%02x", ctrl->nr, sdev->usid);
err = device_add(&sdev->dev);
if (err < 0) {
dev_err(&sdev->dev, "Can't add %s, status %d\n",
dev_name(&sdev->dev), err);
goto err_device_add;
}
dev_dbg(&sdev->dev, "device %s registered\n", dev_name(&sdev->dev));
err_device_add:
return err;
}
EXPORT_SYMBOL_GPL(spmi_device_add);
/**
* spmi_device_remove(): remove an SPMI device
* @sdev: spmi_device to be removed
*/
void spmi_device_remove(struct spmi_device *sdev)
{
device_unregister(&sdev->dev);
}
EXPORT_SYMBOL_GPL(spmi_device_remove);
static inline int
spmi_cmd(struct spmi_controller *ctrl, u8 opcode, u8 sid)
{
int ret;
if (!ctrl || !ctrl->cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
ret = ctrl->cmd(ctrl, opcode, sid);
trace_spmi_cmd(opcode, sid, ret);
return ret;
}
static inline int spmi_read_cmd(struct spmi_controller *ctrl, u8 opcode,
u8 sid, u16 addr, u8 *buf, size_t len)
{
int ret;
if (!ctrl || !ctrl->read_cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
trace_spmi_read_begin(opcode, sid, addr);
ret = ctrl->read_cmd(ctrl, opcode, sid, addr, buf, len);
trace_spmi_read_end(opcode, sid, addr, ret, len, buf);
return ret;
}
static inline int spmi_write_cmd(struct spmi_controller *ctrl, u8 opcode,
u8 sid, u16 addr, const u8 *buf, size_t len)
{
int ret;
if (!ctrl || !ctrl->write_cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
trace_spmi_write_begin(opcode, sid, addr, len, buf);
ret = ctrl->write_cmd(ctrl, opcode, sid, addr, buf, len);
trace_spmi_write_end(opcode, sid, addr, ret);
return ret;
}
/**
* spmi_register_read() - register read
* @sdev: SPMI device.
* @addr: slave register address (5-bit address).
* @buf: buffer to be populated with data from the Slave.
*
* Reads 1 byte of data from a Slave device register.
*/
int spmi_register_read(struct spmi_device *sdev, u8 addr, u8 *buf)
{
/* 5-bit register address */
if (addr > 0x1F)
return -EINVAL;
return spmi_read_cmd(sdev->ctrl, SPMI_CMD_READ, sdev->usid, addr,
buf, 1);
}
EXPORT_SYMBOL_GPL(spmi_register_read);
/**
* spmi_ext_register_read() - extended register read
* @sdev: SPMI device.
* @addr: slave register address (8-bit address).
* @buf: buffer to be populated with data from the Slave.
* @len: the request number of bytes to read (up to 16 bytes).
*
* Reads up to 16 bytes of data from the extended register space on a
* Slave device.
*/
int spmi_ext_register_read(struct spmi_device *sdev, u8 addr, u8 *buf,
size_t len)
{
/* 8-bit register address, up to 16 bytes */
if (len == 0 || len > 16)
return -EINVAL;
return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READ, sdev->usid, addr,
buf, len);
}
EXPORT_SYMBOL_GPL(spmi_ext_register_read);
/**
* spmi_ext_register_readl() - extended register read long
* @sdev: SPMI device.
* @addr: slave register address (16-bit address).
* @buf: buffer to be populated with data from the Slave.
* @len: the request number of bytes to read (up to 8 bytes).
*
* Reads up to 8 bytes of data from the extended register space on a
* Slave device using 16-bit address.
*/
int spmi_ext_register_readl(struct spmi_device *sdev, u16 addr, u8 *buf,
size_t len)
{
/* 16-bit register address, up to 8 bytes */
if (len == 0 || len > 8)
return -EINVAL;
return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READL, sdev->usid, addr,
buf, len);
}
EXPORT_SYMBOL_GPL(spmi_ext_register_readl);
/**
* spmi_register_write() - register write
* @sdev: SPMI device
* @addr: slave register address (5-bit address).
* @data: buffer containing the data to be transferred to the Slave.
*
* Writes 1 byte of data to a Slave device register.
*/
int spmi_register_write(struct spmi_device *sdev, u8 addr, u8 data)
{
/* 5-bit register address */
if (addr > 0x1F)
return -EINVAL;
return spmi_write_cmd(sdev->ctrl, SPMI_CMD_WRITE, sdev->usid, addr,
&data, 1);
}
EXPORT_SYMBOL_GPL(spmi_register_write);
/**
* spmi_register_zero_write() - register zero write
* @sdev: SPMI device.
* @data: the data to be written to register 0 (7-bits).
*
* Writes data to register 0 of the Slave device.
*/
int spmi_register_zero_write(struct spmi_device *sdev, u8 data)
{
return spmi_write_cmd(sdev->ctrl, SPMI_CMD_ZERO_WRITE, sdev->usid, 0,
&data, 1);
}
EXPORT_SYMBOL_GPL(spmi_register_zero_write);
/**
* spmi_ext_register_write() - extended register write
* @sdev: SPMI device.
* @addr: slave register address (8-bit address).
* @buf: buffer containing the data to be transferred to the Slave.
* @len: the request number of bytes to read (up to 16 bytes).
*
* Writes up to 16 bytes of data to the extended register space of a
* Slave device.
*/
int spmi_ext_register_write(struct spmi_device *sdev, u8 addr, const u8 *buf,
size_t len)
{
/* 8-bit register address, up to 16 bytes */
if (len == 0 || len > 16)
return -EINVAL;
return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITE, sdev->usid, addr,
buf, len);
}
EXPORT_SYMBOL_GPL(spmi_ext_register_write);
/**
* spmi_ext_register_writel() - extended register write long
* @sdev: SPMI device.
* @addr: slave register address (16-bit address).
* @buf: buffer containing the data to be transferred to the Slave.
* @len: the request number of bytes to read (up to 8 bytes).
*
* Writes up to 8 bytes of data to the extended register space of a
* Slave device using 16-bit address.
*/
int spmi_ext_register_writel(struct spmi_device *sdev, u16 addr, const u8 *buf,
size_t len)
{
/* 4-bit Slave Identifier, 16-bit register address, up to 8 bytes */
if (len == 0 || len > 8)
return -EINVAL;
return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITEL, sdev->usid,
addr, buf, len);
}
EXPORT_SYMBOL_GPL(spmi_ext_register_writel);
/**
* spmi_command_reset() - sends RESET command to the specified slave
* @sdev: SPMI device.
*
* The Reset command initializes the Slave and forces all registers to
* their reset values. The Slave shall enter the STARTUP state after
* receiving a Reset command.
*/
int spmi_command_reset(struct spmi_device *sdev)
{
return spmi_cmd(sdev->ctrl, SPMI_CMD_RESET, sdev->usid);
}
EXPORT_SYMBOL_GPL(spmi_command_reset);
/**
* spmi_command_sleep() - sends SLEEP command to the specified SPMI device
* @sdev: SPMI device.
*
* The Sleep command causes the Slave to enter the user defined SLEEP state.
*/
int spmi_command_sleep(struct spmi_device *sdev)
{
return spmi_cmd(sdev->ctrl, SPMI_CMD_SLEEP, sdev->usid);
}
EXPORT_SYMBOL_GPL(spmi_command_sleep);
/**
* spmi_command_wakeup() - sends WAKEUP command to the specified SPMI device
* @sdev: SPMI device.
*
* The Wakeup command causes the Slave to move from the SLEEP state to
* the ACTIVE state.
*/
int spmi_command_wakeup(struct spmi_device *sdev)
{
return spmi_cmd(sdev->ctrl, SPMI_CMD_WAKEUP, sdev->usid);
}
EXPORT_SYMBOL_GPL(spmi_command_wakeup);
/**
* spmi_command_shutdown() - sends SHUTDOWN command to the specified SPMI device
* @sdev: SPMI device.
*
* The Shutdown command causes the Slave to enter the SHUTDOWN state.
*/
int spmi_command_shutdown(struct spmi_device *sdev)
{
return spmi_cmd(sdev->ctrl, SPMI_CMD_SHUTDOWN, sdev->usid);
}
EXPORT_SYMBOL_GPL(spmi_command_shutdown);
static int spmi_drv_probe(struct device *dev)
{
const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);
struct spmi_device *sdev = to_spmi_device(dev);
int err;
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
err = sdrv->probe(sdev);
if (err)
goto fail_probe;
return 0;
fail_probe:
pm_runtime_disable(dev);
pm_runtime_set_suspended(dev);
pm_runtime_put_noidle(dev);
return err;
}
static int spmi_drv_remove(struct device *dev)
{
const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);
pm_runtime_get_sync(dev);
sdrv->remove(to_spmi_device(dev));
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
pm_runtime_set_suspended(dev);
pm_runtime_put_noidle(dev);
return 0;
}
static struct bus_type spmi_bus_type = {
.name = "spmi",
.match = spmi_device_match,
.probe = spmi_drv_probe,
.remove = spmi_drv_remove,
};
/**
* spmi_controller_alloc() - Allocate a new SPMI device
* @ctrl: associated controller
*
* Caller is responsible for either calling spmi_device_add() to add the
* newly allocated controller, or calling spmi_device_put() to discard it.
*/
struct spmi_device *spmi_device_alloc(struct spmi_controller *ctrl)
{
struct spmi_device *sdev;
sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
if (!sdev)
return NULL;
sdev->ctrl = ctrl;
device_initialize(&sdev->dev);
sdev->dev.parent = &ctrl->dev;
sdev->dev.bus = &spmi_bus_type;
sdev->dev.type = &spmi_dev_type;
return sdev;
}
EXPORT_SYMBOL_GPL(spmi_device_alloc);
/**
* spmi_controller_alloc() - Allocate a new SPMI controller
* @parent: parent device
* @size: size of private data
*
* Caller is responsible for either calling spmi_controller_add() to add the
* newly allocated controller, or calling spmi_controller_put() to discard it.
* The allocated private data region may be accessed via
* spmi_controller_get_drvdata()
*/
struct spmi_controller *spmi_controller_alloc(struct device *parent,
size_t size)
{
struct spmi_controller *ctrl;
int id;
if (WARN_ON(!parent))
return NULL;
ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL);
if (!ctrl)
return NULL;
device_initialize(&ctrl->dev);
ctrl->dev.type = &spmi_ctrl_type;
ctrl->dev.bus = &spmi_bus_type;
ctrl->dev.parent = parent;
ctrl->dev.of_node = parent->of_node;
spmi_controller_set_drvdata(ctrl, &ctrl[1]);
id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL);
if (id < 0) {
dev_err(parent,
"unable to allocate SPMI controller identifier.\n");
spmi_controller_put(ctrl);
return NULL;
}
ctrl->nr = id;
dev_set_name(&ctrl->dev, "spmi-%d", id);
dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
return ctrl;
}
EXPORT_SYMBOL_GPL(spmi_controller_alloc);
static void of_spmi_register_devices(struct spmi_controller *ctrl)
{
struct device_node *node;
int err;
if (!ctrl->dev.of_node)
return;
for_each_available_child_of_node(ctrl->dev.of_node, node) {
struct spmi_device *sdev;
u32 reg[2];
dev_dbg(&ctrl->dev, "adding child %s\n", node->full_name);
err = of_property_read_u32_array(node, "reg", reg, 2);
if (err) {
dev_err(&ctrl->dev,
"node %s err (%d) does not have 'reg' property\n",
node->full_name, err);
continue;
}
if (reg[1] != SPMI_USID) {
dev_err(&ctrl->dev,
"node %s contains unsupported 'reg' entry\n",
node->full_name);
continue;
}
if (reg[0] >= SPMI_MAX_SLAVE_ID) {
dev_err(&ctrl->dev,
"invalid usid on node %s\n",
node->full_name);
continue;
}
dev_dbg(&ctrl->dev, "read usid %02x\n", reg[0]);
sdev = spmi_device_alloc(ctrl);
if (!sdev)
continue;
sdev->dev.of_node = node;
sdev->usid = (u8) reg[0];
err = spmi_device_add(sdev);
if (err) {
dev_err(&sdev->dev,
"failure adding device. status %d\n", err);
spmi_device_put(sdev);
}
}
}
/**
* spmi_controller_add() - Add an SPMI controller
* @ctrl: controller to be registered.
*
* Register a controller previously allocated via spmi_controller_alloc() with
* the SPMI core.
*/
int spmi_controller_add(struct spmi_controller *ctrl)
{
int ret;
/* Can't register until after driver model init */
if (WARN_ON(!spmi_bus_type.p))
return -EAGAIN;
ret = device_add(&ctrl->dev);
if (ret)
return ret;
if (IS_ENABLED(CONFIG_OF))
of_spmi_register_devices(ctrl);
dev_dbg(&ctrl->dev, "spmi-%d registered: dev:%p\n",
ctrl->nr, &ctrl->dev);
return 0;
};
EXPORT_SYMBOL_GPL(spmi_controller_add);
/* Remove a device associated with a controller */
static int spmi_ctrl_remove_device(struct device *dev, void *data)
{
struct spmi_device *spmidev = to_spmi_device(dev);
if (dev->type == &spmi_dev_type)
spmi_device_remove(spmidev);
return 0;
}
/**
* spmi_controller_remove(): remove an SPMI controller
* @ctrl: controller to remove
*
* Remove a SPMI controller. Caller is responsible for calling
* spmi_controller_put() to discard the allocated controller.
*/
void spmi_controller_remove(struct spmi_controller *ctrl)
{
int dummy;
if (!ctrl)
return;
dummy = device_for_each_child(&ctrl->dev, NULL,
spmi_ctrl_remove_device);
device_del(&ctrl->dev);
}
EXPORT_SYMBOL_GPL(spmi_controller_remove);
/**
* spmi_driver_register() - Register client driver with SPMI core
* @sdrv: client driver to be associated with client-device.
*
* This API will register the client driver with the SPMI framework.
* It is typically called from the driver's module-init function.
*/
int __spmi_driver_register(struct spmi_driver *sdrv, struct module *owner)
{
sdrv->driver.bus = &spmi_bus_type;
sdrv->driver.owner = owner;
return driver_register(&sdrv->driver);
}
EXPORT_SYMBOL_GPL(__spmi_driver_register);
static void __exit spmi_exit(void)
{
bus_unregister(&spmi_bus_type);
}
module_exit(spmi_exit);
static int __init spmi_init(void)
{
return bus_register(&spmi_bus_type);
}
postcore_initcall(spmi_init);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("SPMI module");
MODULE_ALIAS("platform:spmi");