linux/drivers/spmi/spmi.c
Gilad Avidov 0b9641f572 spmi: remove wakeup command before slave probe
According to spmi spec a slave powers up into startup state and then
transitions into active state. Thus, the wakeup command is not required
before calling the slave's probe. The wakeup command is only needed for
slaves that are in sleep state after receiving the sleep command.

Cc: galak@codeaurora.org
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Sagar Dharia <sdharia@codeaurora.org>
Acked-by: Josh Cartwright <joshc@eso.teric.us>
Signed-off-by: Gilad Avidov <gavidov@codeaurora.org>
Tested-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 23:51:36 +01:00

569 lines
14 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>
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)
{
if (!ctrl || !ctrl->cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
return ctrl->cmd(ctrl, opcode, sid);
}
static inline int spmi_read_cmd(struct spmi_controller *ctrl, u8 opcode,
u8 sid, u16 addr, u8 *buf, size_t len)
{
if (!ctrl || !ctrl->read_cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
return ctrl->read_cmd(ctrl, opcode, sid, addr, buf, len);
}
static inline int spmi_write_cmd(struct spmi_controller *ctrl, u8 opcode,
u8 sid, u16 addr, const u8 *buf, size_t len)
{
if (!ctrl || !ctrl->write_cmd || ctrl->dev.type != &spmi_ctrl_type)
return -EINVAL;
return ctrl->write_cmd(ctrl, opcode, sid, addr, buf, len);
}
/**
* 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)
{
sdrv->driver.bus = &spmi_bus_type;
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");