389 lines
9.3 KiB
C
389 lines
9.3 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-only
|
||
|
|
/*
|
||
|
|
* Copyright (c) 2011-2016 Synaptics Incorporated
|
||
|
|
* Copyright (c) 2011 Unixphere
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/i2c.h>
|
||
|
|
#include <linux/rmi.h>
|
||
|
|
#include <linux/of.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/regulator/consumer.h>
|
||
|
|
#include "rmi_driver.h"
|
||
|
|
|
||
|
|
#define BUFFER_SIZE_INCREMENT 32
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct rmi_i2c_xport - stores information for i2c communication
|
||
|
|
*
|
||
|
|
* @xport: The transport interface structure
|
||
|
|
* @client: The I2C client device structure
|
||
|
|
*
|
||
|
|
* @page_mutex: Locks current page to avoid changing pages in unexpected ways.
|
||
|
|
* @page: Keeps track of the current virtual page
|
||
|
|
*
|
||
|
|
* @tx_buf: Buffer used for transmitting data to the sensor over i2c.
|
||
|
|
* @tx_buf_size: Size of the buffer
|
||
|
|
*
|
||
|
|
* @supplies: Array of voltage regulators
|
||
|
|
* @startup_delay: Milliseconds to pause after powering up the regulators
|
||
|
|
*/
|
||
|
|
struct rmi_i2c_xport {
|
||
|
|
struct rmi_transport_dev xport;
|
||
|
|
struct i2c_client *client;
|
||
|
|
|
||
|
|
struct mutex page_mutex;
|
||
|
|
int page;
|
||
|
|
|
||
|
|
u8 *tx_buf;
|
||
|
|
size_t tx_buf_size;
|
||
|
|
|
||
|
|
struct regulator_bulk_data supplies[2];
|
||
|
|
u32 startup_delay;
|
||
|
|
};
|
||
|
|
|
||
|
|
#define RMI_PAGE_SELECT_REGISTER 0xff
|
||
|
|
#define RMI_I2C_PAGE(addr) (((addr) >> 8) & 0xff)
|
||
|
|
|
||
|
|
/*
|
||
|
|
* rmi_set_page - Set RMI page
|
||
|
|
* @xport: The pointer to the rmi_transport_dev struct
|
||
|
|
* @page: The new page address.
|
||
|
|
*
|
||
|
|
* RMI devices have 16-bit addressing, but some of the transport
|
||
|
|
* implementations (like SMBus) only have 8-bit addressing. So RMI implements
|
||
|
|
* a page address at 0xff of every page so we can reliable page addresses
|
||
|
|
* every 256 registers.
|
||
|
|
*
|
||
|
|
* The page_mutex lock must be held when this function is entered.
|
||
|
|
*
|
||
|
|
* Returns zero on success, non-zero on failure.
|
||
|
|
*/
|
||
|
|
static int rmi_set_page(struct rmi_i2c_xport *rmi_i2c, u8 page)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = rmi_i2c->client;
|
||
|
|
u8 txbuf[2] = {RMI_PAGE_SELECT_REGISTER, page};
|
||
|
|
int retval;
|
||
|
|
|
||
|
|
retval = i2c_master_send(client, txbuf, sizeof(txbuf));
|
||
|
|
if (retval != sizeof(txbuf)) {
|
||
|
|
dev_err(&client->dev,
|
||
|
|
"%s: set page failed: %d.", __func__, retval);
|
||
|
|
return (retval < 0) ? retval : -EIO;
|
||
|
|
}
|
||
|
|
|
||
|
|
rmi_i2c->page = page;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_write_block(struct rmi_transport_dev *xport, u16 addr,
|
||
|
|
const void *buf, size_t len)
|
||
|
|
{
|
||
|
|
struct rmi_i2c_xport *rmi_i2c =
|
||
|
|
container_of(xport, struct rmi_i2c_xport, xport);
|
||
|
|
struct i2c_client *client = rmi_i2c->client;
|
||
|
|
size_t tx_size = len + 1;
|
||
|
|
int retval;
|
||
|
|
|
||
|
|
mutex_lock(&rmi_i2c->page_mutex);
|
||
|
|
|
||
|
|
if (!rmi_i2c->tx_buf || rmi_i2c->tx_buf_size < tx_size) {
|
||
|
|
if (rmi_i2c->tx_buf)
|
||
|
|
devm_kfree(&client->dev, rmi_i2c->tx_buf);
|
||
|
|
rmi_i2c->tx_buf_size = tx_size + BUFFER_SIZE_INCREMENT;
|
||
|
|
rmi_i2c->tx_buf = devm_kzalloc(&client->dev,
|
||
|
|
rmi_i2c->tx_buf_size,
|
||
|
|
GFP_KERNEL);
|
||
|
|
if (!rmi_i2c->tx_buf) {
|
||
|
|
rmi_i2c->tx_buf_size = 0;
|
||
|
|
retval = -ENOMEM;
|
||
|
|
goto exit;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
rmi_i2c->tx_buf[0] = addr & 0xff;
|
||
|
|
memcpy(rmi_i2c->tx_buf + 1, buf, len);
|
||
|
|
|
||
|
|
if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
|
||
|
|
retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
|
||
|
|
if (retval)
|
||
|
|
goto exit;
|
||
|
|
}
|
||
|
|
|
||
|
|
retval = i2c_master_send(client, rmi_i2c->tx_buf, tx_size);
|
||
|
|
if (retval == tx_size)
|
||
|
|
retval = 0;
|
||
|
|
else if (retval >= 0)
|
||
|
|
retval = -EIO;
|
||
|
|
|
||
|
|
exit:
|
||
|
|
rmi_dbg(RMI_DEBUG_XPORT, &client->dev,
|
||
|
|
"write %zd bytes at %#06x: %d (%*ph)\n",
|
||
|
|
len, addr, retval, (int)len, buf);
|
||
|
|
|
||
|
|
mutex_unlock(&rmi_i2c->page_mutex);
|
||
|
|
return retval;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_read_block(struct rmi_transport_dev *xport, u16 addr,
|
||
|
|
void *buf, size_t len)
|
||
|
|
{
|
||
|
|
struct rmi_i2c_xport *rmi_i2c =
|
||
|
|
container_of(xport, struct rmi_i2c_xport, xport);
|
||
|
|
struct i2c_client *client = rmi_i2c->client;
|
||
|
|
u8 addr_offset = addr & 0xff;
|
||
|
|
int retval;
|
||
|
|
struct i2c_msg msgs[] = {
|
||
|
|
{
|
||
|
|
.addr = client->addr,
|
||
|
|
.len = sizeof(addr_offset),
|
||
|
|
.buf = &addr_offset,
|
||
|
|
},
|
||
|
|
{
|
||
|
|
.addr = client->addr,
|
||
|
|
.flags = I2C_M_RD,
|
||
|
|
.len = len,
|
||
|
|
.buf = buf,
|
||
|
|
},
|
||
|
|
};
|
||
|
|
|
||
|
|
mutex_lock(&rmi_i2c->page_mutex);
|
||
|
|
|
||
|
|
if (RMI_I2C_PAGE(addr) != rmi_i2c->page) {
|
||
|
|
retval = rmi_set_page(rmi_i2c, RMI_I2C_PAGE(addr));
|
||
|
|
if (retval)
|
||
|
|
goto exit;
|
||
|
|
}
|
||
|
|
|
||
|
|
retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
|
||
|
|
if (retval == ARRAY_SIZE(msgs))
|
||
|
|
retval = 0; /* success */
|
||
|
|
else if (retval >= 0)
|
||
|
|
retval = -EIO;
|
||
|
|
|
||
|
|
exit:
|
||
|
|
rmi_dbg(RMI_DEBUG_XPORT, &client->dev,
|
||
|
|
"read %zd bytes at %#06x: %d (%*ph)\n",
|
||
|
|
len, addr, retval, (int)len, buf);
|
||
|
|
|
||
|
|
mutex_unlock(&rmi_i2c->page_mutex);
|
||
|
|
return retval;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct rmi_transport_ops rmi_i2c_ops = {
|
||
|
|
.write_block = rmi_i2c_write_block,
|
||
|
|
.read_block = rmi_i2c_read_block,
|
||
|
|
};
|
||
|
|
|
||
|
|
#ifdef CONFIG_OF
|
||
|
|
static const struct of_device_id rmi_i2c_of_match[] = {
|
||
|
|
{ .compatible = "syna,rmi4-i2c" },
|
||
|
|
{},
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, rmi_i2c_of_match);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static void rmi_i2c_regulator_bulk_disable(void *data)
|
||
|
|
{
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = data;
|
||
|
|
|
||
|
|
regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void rmi_i2c_unregister_transport(void *data)
|
||
|
|
{
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = data;
|
||
|
|
|
||
|
|
rmi_unregister_transport_device(&rmi_i2c->xport);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_probe(struct i2c_client *client)
|
||
|
|
{
|
||
|
|
struct rmi_device_platform_data *pdata;
|
||
|
|
struct rmi_device_platform_data *client_pdata =
|
||
|
|
dev_get_platdata(&client->dev);
|
||
|
|
struct rmi_i2c_xport *rmi_i2c;
|
||
|
|
int error;
|
||
|
|
|
||
|
|
rmi_i2c = devm_kzalloc(&client->dev, sizeof(struct rmi_i2c_xport),
|
||
|
|
GFP_KERNEL);
|
||
|
|
if (!rmi_i2c)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
pdata = &rmi_i2c->xport.pdata;
|
||
|
|
|
||
|
|
if (!client->dev.of_node && client_pdata)
|
||
|
|
*pdata = *client_pdata;
|
||
|
|
|
||
|
|
pdata->irq = client->irq;
|
||
|
|
|
||
|
|
rmi_dbg(RMI_DEBUG_XPORT, &client->dev, "Probing %s.\n",
|
||
|
|
dev_name(&client->dev));
|
||
|
|
|
||
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
|
||
|
|
dev_err(&client->dev,
|
||
|
|
"adapter does not support required functionality\n");
|
||
|
|
return -ENODEV;
|
||
|
|
}
|
||
|
|
|
||
|
|
rmi_i2c->supplies[0].supply = "vdd";
|
||
|
|
rmi_i2c->supplies[1].supply = "vio";
|
||
|
|
error = devm_regulator_bulk_get(&client->dev,
|
||
|
|
ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
if (error < 0)
|
||
|
|
return error;
|
||
|
|
|
||
|
|
error = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
if (error < 0)
|
||
|
|
return error;
|
||
|
|
|
||
|
|
error = devm_add_action_or_reset(&client->dev,
|
||
|
|
rmi_i2c_regulator_bulk_disable,
|
||
|
|
rmi_i2c);
|
||
|
|
if (error)
|
||
|
|
return error;
|
||
|
|
|
||
|
|
of_property_read_u32(client->dev.of_node, "syna,startup-delay-ms",
|
||
|
|
&rmi_i2c->startup_delay);
|
||
|
|
|
||
|
|
msleep(rmi_i2c->startup_delay);
|
||
|
|
|
||
|
|
rmi_i2c->client = client;
|
||
|
|
mutex_init(&rmi_i2c->page_mutex);
|
||
|
|
|
||
|
|
rmi_i2c->xport.dev = &client->dev;
|
||
|
|
rmi_i2c->xport.proto_name = "i2c";
|
||
|
|
rmi_i2c->xport.ops = &rmi_i2c_ops;
|
||
|
|
|
||
|
|
i2c_set_clientdata(client, rmi_i2c);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Setting the page to zero will (a) make sure the PSR is in a
|
||
|
|
* known state, and (b) make sure we can talk to the device.
|
||
|
|
*/
|
||
|
|
error = rmi_set_page(rmi_i2c, 0);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&client->dev, "Failed to set page select to 0\n");
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
dev_info(&client->dev, "registering I2C-connected sensor\n");
|
||
|
|
|
||
|
|
error = rmi_register_transport_device(&rmi_i2c->xport);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&client->dev, "failed to register sensor: %d\n", error);
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
error = devm_add_action_or_reset(&client->dev,
|
||
|
|
rmi_i2c_unregister_transport,
|
||
|
|
rmi_i2c);
|
||
|
|
if (error)
|
||
|
|
return error;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_suspend(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = rmi_driver_suspend(rmi_i2c->xport.rmi_dev, true);
|
||
|
|
if (ret)
|
||
|
|
dev_warn(dev, "Failed to resume device: %d\n", ret);
|
||
|
|
|
||
|
|
regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_resume(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
msleep(rmi_i2c->startup_delay);
|
||
|
|
|
||
|
|
ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev, true);
|
||
|
|
if (ret)
|
||
|
|
dev_warn(dev, "Failed to resume device: %d\n", ret);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_runtime_suspend(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = rmi_driver_suspend(rmi_i2c->xport.rmi_dev, false);
|
||
|
|
if (ret)
|
||
|
|
dev_warn(dev, "Failed to resume device: %d\n", ret);
|
||
|
|
|
||
|
|
regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int rmi_i2c_runtime_resume(struct device *dev)
|
||
|
|
{
|
||
|
|
struct i2c_client *client = to_i2c_client(dev);
|
||
|
|
struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client);
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies),
|
||
|
|
rmi_i2c->supplies);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
msleep(rmi_i2c->startup_delay);
|
||
|
|
|
||
|
|
ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev, false);
|
||
|
|
if (ret)
|
||
|
|
dev_warn(dev, "Failed to resume device: %d\n", ret);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct dev_pm_ops rmi_i2c_pm = {
|
||
|
|
SYSTEM_SLEEP_PM_OPS(rmi_i2c_suspend, rmi_i2c_resume)
|
||
|
|
RUNTIME_PM_OPS(rmi_i2c_runtime_suspend, rmi_i2c_runtime_resume, NULL)
|
||
|
|
};
|
||
|
|
|
||
|
|
static const struct i2c_device_id rmi_id[] = {
|
||
|
|
{ "rmi4_i2c", 0 },
|
||
|
|
{ }
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(i2c, rmi_id);
|
||
|
|
|
||
|
|
static struct i2c_driver rmi_i2c_driver = {
|
||
|
|
.driver = {
|
||
|
|
.name = "rmi4_i2c",
|
||
|
|
.pm = pm_ptr(&rmi_i2c_pm),
|
||
|
|
.of_match_table = of_match_ptr(rmi_i2c_of_match),
|
||
|
|
},
|
||
|
|
.id_table = rmi_id,
|
||
|
|
.probe_new = rmi_i2c_probe,
|
||
|
|
};
|
||
|
|
|
||
|
|
module_i2c_driver(rmi_i2c_driver);
|
||
|
|
|
||
|
|
MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com>");
|
||
|
|
MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com>");
|
||
|
|
MODULE_DESCRIPTION("RMI I2C driver");
|
||
|
|
MODULE_LICENSE("GPL");
|