mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
533 lines
12 KiB
533 lines
12 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* Copyright (c) 2011-2016 Synaptics Incorporated |
|
* Copyright (c) 2011 Unixphere |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/rmi.h> |
|
#include <linux/slab.h> |
|
#include <linux/spi/spi.h> |
|
#include <linux/of.h> |
|
#include "rmi_driver.h" |
|
|
|
#define RMI_SPI_DEFAULT_XFER_BUF_SIZE 64 |
|
|
|
#define RMI_PAGE_SELECT_REGISTER 0x00FF |
|
#define RMI_SPI_PAGE(addr) (((addr) >> 8) & 0x80) |
|
#define RMI_SPI_XFER_SIZE_LIMIT 255 |
|
|
|
#define BUFFER_SIZE_INCREMENT 32 |
|
|
|
enum rmi_spi_op { |
|
RMI_SPI_WRITE = 0, |
|
RMI_SPI_READ, |
|
RMI_SPI_V2_READ_UNIFIED, |
|
RMI_SPI_V2_READ_SPLIT, |
|
RMI_SPI_V2_WRITE, |
|
}; |
|
|
|
struct rmi_spi_cmd { |
|
enum rmi_spi_op op; |
|
u16 addr; |
|
}; |
|
|
|
struct rmi_spi_xport { |
|
struct rmi_transport_dev xport; |
|
struct spi_device *spi; |
|
|
|
struct mutex page_mutex; |
|
int page; |
|
|
|
u8 *rx_buf; |
|
u8 *tx_buf; |
|
int xfer_buf_size; |
|
|
|
struct spi_transfer *rx_xfers; |
|
struct spi_transfer *tx_xfers; |
|
int rx_xfer_count; |
|
int tx_xfer_count; |
|
}; |
|
|
|
static int rmi_spi_manage_pools(struct rmi_spi_xport *rmi_spi, int len) |
|
{ |
|
struct spi_device *spi = rmi_spi->spi; |
|
int buf_size = rmi_spi->xfer_buf_size |
|
? rmi_spi->xfer_buf_size : RMI_SPI_DEFAULT_XFER_BUF_SIZE; |
|
struct spi_transfer *xfer_buf; |
|
void *buf; |
|
void *tmp; |
|
|
|
while (buf_size < len) |
|
buf_size *= 2; |
|
|
|
if (buf_size > RMI_SPI_XFER_SIZE_LIMIT) |
|
buf_size = RMI_SPI_XFER_SIZE_LIMIT; |
|
|
|
tmp = rmi_spi->rx_buf; |
|
buf = devm_kcalloc(&spi->dev, buf_size, 2, |
|
GFP_KERNEL | GFP_DMA); |
|
if (!buf) |
|
return -ENOMEM; |
|
|
|
rmi_spi->rx_buf = buf; |
|
rmi_spi->tx_buf = &rmi_spi->rx_buf[buf_size]; |
|
rmi_spi->xfer_buf_size = buf_size; |
|
|
|
if (tmp) |
|
devm_kfree(&spi->dev, tmp); |
|
|
|
if (rmi_spi->xport.pdata.spi_data.read_delay_us) |
|
rmi_spi->rx_xfer_count = buf_size; |
|
else |
|
rmi_spi->rx_xfer_count = 1; |
|
|
|
if (rmi_spi->xport.pdata.spi_data.write_delay_us) |
|
rmi_spi->tx_xfer_count = buf_size; |
|
else |
|
rmi_spi->tx_xfer_count = 1; |
|
|
|
/* |
|
* Allocate a pool of spi_transfer buffers for devices which need |
|
* per byte delays. |
|
*/ |
|
tmp = rmi_spi->rx_xfers; |
|
xfer_buf = devm_kcalloc(&spi->dev, |
|
rmi_spi->rx_xfer_count + rmi_spi->tx_xfer_count, |
|
sizeof(struct spi_transfer), |
|
GFP_KERNEL); |
|
if (!xfer_buf) |
|
return -ENOMEM; |
|
|
|
rmi_spi->rx_xfers = xfer_buf; |
|
rmi_spi->tx_xfers = &xfer_buf[rmi_spi->rx_xfer_count]; |
|
|
|
if (tmp) |
|
devm_kfree(&spi->dev, tmp); |
|
|
|
return 0; |
|
} |
|
|
|
static int rmi_spi_xfer(struct rmi_spi_xport *rmi_spi, |
|
const struct rmi_spi_cmd *cmd, const u8 *tx_buf, |
|
int tx_len, u8 *rx_buf, int rx_len) |
|
{ |
|
struct spi_device *spi = rmi_spi->spi; |
|
struct rmi_device_platform_data_spi *spi_data = |
|
&rmi_spi->xport.pdata.spi_data; |
|
struct spi_message msg; |
|
struct spi_transfer *xfer; |
|
int ret = 0; |
|
int len; |
|
int cmd_len = 0; |
|
int total_tx_len; |
|
int i; |
|
u16 addr = cmd->addr; |
|
|
|
spi_message_init(&msg); |
|
|
|
switch (cmd->op) { |
|
case RMI_SPI_WRITE: |
|
case RMI_SPI_READ: |
|
cmd_len += 2; |
|
break; |
|
case RMI_SPI_V2_READ_UNIFIED: |
|
case RMI_SPI_V2_READ_SPLIT: |
|
case RMI_SPI_V2_WRITE: |
|
cmd_len += 4; |
|
break; |
|
} |
|
|
|
total_tx_len = cmd_len + tx_len; |
|
len = max(total_tx_len, rx_len); |
|
|
|
if (len > RMI_SPI_XFER_SIZE_LIMIT) |
|
return -EINVAL; |
|
|
|
if (rmi_spi->xfer_buf_size < len) { |
|
ret = rmi_spi_manage_pools(rmi_spi, len); |
|
if (ret < 0) |
|
return ret; |
|
} |
|
|
|
if (addr == 0) |
|
/* |
|
* SPI needs an address. Use 0x7FF if we want to keep |
|
* reading from the last position of the register pointer. |
|
*/ |
|
addr = 0x7FF; |
|
|
|
switch (cmd->op) { |
|
case RMI_SPI_WRITE: |
|
rmi_spi->tx_buf[0] = (addr >> 8); |
|
rmi_spi->tx_buf[1] = addr & 0xFF; |
|
break; |
|
case RMI_SPI_READ: |
|
rmi_spi->tx_buf[0] = (addr >> 8) | 0x80; |
|
rmi_spi->tx_buf[1] = addr & 0xFF; |
|
break; |
|
case RMI_SPI_V2_READ_UNIFIED: |
|
break; |
|
case RMI_SPI_V2_READ_SPLIT: |
|
break; |
|
case RMI_SPI_V2_WRITE: |
|
rmi_spi->tx_buf[0] = 0x40; |
|
rmi_spi->tx_buf[1] = (addr >> 8) & 0xFF; |
|
rmi_spi->tx_buf[2] = addr & 0xFF; |
|
rmi_spi->tx_buf[3] = tx_len; |
|
break; |
|
} |
|
|
|
if (tx_buf) |
|
memcpy(&rmi_spi->tx_buf[cmd_len], tx_buf, tx_len); |
|
|
|
if (rmi_spi->tx_xfer_count > 1) { |
|
for (i = 0; i < total_tx_len; i++) { |
|
xfer = &rmi_spi->tx_xfers[i]; |
|
memset(xfer, 0, sizeof(struct spi_transfer)); |
|
xfer->tx_buf = &rmi_spi->tx_buf[i]; |
|
xfer->len = 1; |
|
xfer->delay.value = spi_data->write_delay_us; |
|
xfer->delay.unit = SPI_DELAY_UNIT_USECS; |
|
spi_message_add_tail(xfer, &msg); |
|
} |
|
} else { |
|
xfer = rmi_spi->tx_xfers; |
|
memset(xfer, 0, sizeof(struct spi_transfer)); |
|
xfer->tx_buf = rmi_spi->tx_buf; |
|
xfer->len = total_tx_len; |
|
spi_message_add_tail(xfer, &msg); |
|
} |
|
|
|
rmi_dbg(RMI_DEBUG_XPORT, &spi->dev, "%s: cmd: %s tx_buf len: %d tx_buf: %*ph\n", |
|
__func__, cmd->op == RMI_SPI_WRITE ? "WRITE" : "READ", |
|
total_tx_len, total_tx_len, rmi_spi->tx_buf); |
|
|
|
if (rx_buf) { |
|
if (rmi_spi->rx_xfer_count > 1) { |
|
for (i = 0; i < rx_len; i++) { |
|
xfer = &rmi_spi->rx_xfers[i]; |
|
memset(xfer, 0, sizeof(struct spi_transfer)); |
|
xfer->rx_buf = &rmi_spi->rx_buf[i]; |
|
xfer->len = 1; |
|
xfer->delay.value = spi_data->read_delay_us; |
|
xfer->delay.unit = SPI_DELAY_UNIT_USECS; |
|
spi_message_add_tail(xfer, &msg); |
|
} |
|
} else { |
|
xfer = rmi_spi->rx_xfers; |
|
memset(xfer, 0, sizeof(struct spi_transfer)); |
|
xfer->rx_buf = rmi_spi->rx_buf; |
|
xfer->len = rx_len; |
|
spi_message_add_tail(xfer, &msg); |
|
} |
|
} |
|
|
|
ret = spi_sync(spi, &msg); |
|
if (ret < 0) { |
|
dev_err(&spi->dev, "spi xfer failed: %d\n", ret); |
|
return ret; |
|
} |
|
|
|
if (rx_buf) { |
|
memcpy(rx_buf, rmi_spi->rx_buf, rx_len); |
|
rmi_dbg(RMI_DEBUG_XPORT, &spi->dev, "%s: (%d) %*ph\n", |
|
__func__, rx_len, rx_len, rx_buf); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* 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_spi_xport *rmi_spi, u8 page) |
|
{ |
|
struct rmi_spi_cmd cmd; |
|
int ret; |
|
|
|
cmd.op = RMI_SPI_WRITE; |
|
cmd.addr = RMI_PAGE_SELECT_REGISTER; |
|
|
|
ret = rmi_spi_xfer(rmi_spi, &cmd, &page, 1, NULL, 0); |
|
|
|
if (ret) |
|
rmi_spi->page = page; |
|
|
|
return ret; |
|
} |
|
|
|
static int rmi_spi_write_block(struct rmi_transport_dev *xport, u16 addr, |
|
const void *buf, size_t len) |
|
{ |
|
struct rmi_spi_xport *rmi_spi = |
|
container_of(xport, struct rmi_spi_xport, xport); |
|
struct rmi_spi_cmd cmd; |
|
int ret; |
|
|
|
mutex_lock(&rmi_spi->page_mutex); |
|
|
|
if (RMI_SPI_PAGE(addr) != rmi_spi->page) { |
|
ret = rmi_set_page(rmi_spi, RMI_SPI_PAGE(addr)); |
|
if (ret) |
|
goto exit; |
|
} |
|
|
|
cmd.op = RMI_SPI_WRITE; |
|
cmd.addr = addr; |
|
|
|
ret = rmi_spi_xfer(rmi_spi, &cmd, buf, len, NULL, 0); |
|
|
|
exit: |
|
mutex_unlock(&rmi_spi->page_mutex); |
|
return ret; |
|
} |
|
|
|
static int rmi_spi_read_block(struct rmi_transport_dev *xport, u16 addr, |
|
void *buf, size_t len) |
|
{ |
|
struct rmi_spi_xport *rmi_spi = |
|
container_of(xport, struct rmi_spi_xport, xport); |
|
struct rmi_spi_cmd cmd; |
|
int ret; |
|
|
|
mutex_lock(&rmi_spi->page_mutex); |
|
|
|
if (RMI_SPI_PAGE(addr) != rmi_spi->page) { |
|
ret = rmi_set_page(rmi_spi, RMI_SPI_PAGE(addr)); |
|
if (ret) |
|
goto exit; |
|
} |
|
|
|
cmd.op = RMI_SPI_READ; |
|
cmd.addr = addr; |
|
|
|
ret = rmi_spi_xfer(rmi_spi, &cmd, NULL, 0, buf, len); |
|
|
|
exit: |
|
mutex_unlock(&rmi_spi->page_mutex); |
|
return ret; |
|
} |
|
|
|
static const struct rmi_transport_ops rmi_spi_ops = { |
|
.write_block = rmi_spi_write_block, |
|
.read_block = rmi_spi_read_block, |
|
}; |
|
|
|
#ifdef CONFIG_OF |
|
static int rmi_spi_of_probe(struct spi_device *spi, |
|
struct rmi_device_platform_data *pdata) |
|
{ |
|
struct device *dev = &spi->dev; |
|
int retval; |
|
|
|
retval = rmi_of_property_read_u32(dev, |
|
&pdata->spi_data.read_delay_us, |
|
"spi-rx-delay-us", 1); |
|
if (retval) |
|
return retval; |
|
|
|
retval = rmi_of_property_read_u32(dev, |
|
&pdata->spi_data.write_delay_us, |
|
"spi-tx-delay-us", 1); |
|
if (retval) |
|
return retval; |
|
|
|
return 0; |
|
} |
|
|
|
static const struct of_device_id rmi_spi_of_match[] = { |
|
{ .compatible = "syna,rmi4-spi" }, |
|
{}, |
|
}; |
|
MODULE_DEVICE_TABLE(of, rmi_spi_of_match); |
|
#else |
|
static inline int rmi_spi_of_probe(struct spi_device *spi, |
|
struct rmi_device_platform_data *pdata) |
|
{ |
|
return -ENODEV; |
|
} |
|
#endif |
|
|
|
static void rmi_spi_unregister_transport(void *data) |
|
{ |
|
struct rmi_spi_xport *rmi_spi = data; |
|
|
|
rmi_unregister_transport_device(&rmi_spi->xport); |
|
} |
|
|
|
static int rmi_spi_probe(struct spi_device *spi) |
|
{ |
|
struct rmi_spi_xport *rmi_spi; |
|
struct rmi_device_platform_data *pdata; |
|
struct rmi_device_platform_data *spi_pdata = spi->dev.platform_data; |
|
int error; |
|
|
|
if (spi->master->flags & SPI_MASTER_HALF_DUPLEX) |
|
return -EINVAL; |
|
|
|
rmi_spi = devm_kzalloc(&spi->dev, sizeof(struct rmi_spi_xport), |
|
GFP_KERNEL); |
|
if (!rmi_spi) |
|
return -ENOMEM; |
|
|
|
pdata = &rmi_spi->xport.pdata; |
|
|
|
if (spi->dev.of_node) { |
|
error = rmi_spi_of_probe(spi, pdata); |
|
if (error) |
|
return error; |
|
} else if (spi_pdata) { |
|
*pdata = *spi_pdata; |
|
} |
|
|
|
if (pdata->spi_data.bits_per_word) |
|
spi->bits_per_word = pdata->spi_data.bits_per_word; |
|
|
|
if (pdata->spi_data.mode) |
|
spi->mode = pdata->spi_data.mode; |
|
|
|
error = spi_setup(spi); |
|
if (error < 0) { |
|
dev_err(&spi->dev, "spi_setup failed!\n"); |
|
return error; |
|
} |
|
|
|
pdata->irq = spi->irq; |
|
|
|
rmi_spi->spi = spi; |
|
mutex_init(&rmi_spi->page_mutex); |
|
|
|
rmi_spi->xport.dev = &spi->dev; |
|
rmi_spi->xport.proto_name = "spi"; |
|
rmi_spi->xport.ops = &rmi_spi_ops; |
|
|
|
spi_set_drvdata(spi, rmi_spi); |
|
|
|
error = rmi_spi_manage_pools(rmi_spi, RMI_SPI_DEFAULT_XFER_BUF_SIZE); |
|
if (error) |
|
return error; |
|
|
|
/* |
|
* 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_spi, 0); |
|
if (error) { |
|
dev_err(&spi->dev, "Failed to set page select to 0.\n"); |
|
return error; |
|
} |
|
|
|
dev_info(&spi->dev, "registering SPI-connected sensor\n"); |
|
|
|
error = rmi_register_transport_device(&rmi_spi->xport); |
|
if (error) { |
|
dev_err(&spi->dev, "failed to register sensor: %d\n", error); |
|
return error; |
|
} |
|
|
|
error = devm_add_action_or_reset(&spi->dev, |
|
rmi_spi_unregister_transport, |
|
rmi_spi); |
|
if (error) |
|
return error; |
|
|
|
return 0; |
|
} |
|
|
|
#ifdef CONFIG_PM_SLEEP |
|
static int rmi_spi_suspend(struct device *dev) |
|
{ |
|
struct spi_device *spi = to_spi_device(dev); |
|
struct rmi_spi_xport *rmi_spi = spi_get_drvdata(spi); |
|
int ret; |
|
|
|
ret = rmi_driver_suspend(rmi_spi->xport.rmi_dev, true); |
|
if (ret) |
|
dev_warn(dev, "Failed to resume device: %d\n", ret); |
|
|
|
return ret; |
|
} |
|
|
|
static int rmi_spi_resume(struct device *dev) |
|
{ |
|
struct spi_device *spi = to_spi_device(dev); |
|
struct rmi_spi_xport *rmi_spi = spi_get_drvdata(spi); |
|
int ret; |
|
|
|
ret = rmi_driver_resume(rmi_spi->xport.rmi_dev, true); |
|
if (ret) |
|
dev_warn(dev, "Failed to resume device: %d\n", ret); |
|
|
|
return ret; |
|
} |
|
#endif |
|
|
|
#ifdef CONFIG_PM |
|
static int rmi_spi_runtime_suspend(struct device *dev) |
|
{ |
|
struct spi_device *spi = to_spi_device(dev); |
|
struct rmi_spi_xport *rmi_spi = spi_get_drvdata(spi); |
|
int ret; |
|
|
|
ret = rmi_driver_suspend(rmi_spi->xport.rmi_dev, false); |
|
if (ret) |
|
dev_warn(dev, "Failed to resume device: %d\n", ret); |
|
|
|
return 0; |
|
} |
|
|
|
static int rmi_spi_runtime_resume(struct device *dev) |
|
{ |
|
struct spi_device *spi = to_spi_device(dev); |
|
struct rmi_spi_xport *rmi_spi = spi_get_drvdata(spi); |
|
int ret; |
|
|
|
ret = rmi_driver_resume(rmi_spi->xport.rmi_dev, false); |
|
if (ret) |
|
dev_warn(dev, "Failed to resume device: %d\n", ret); |
|
|
|
return 0; |
|
} |
|
#endif |
|
|
|
static const struct dev_pm_ops rmi_spi_pm = { |
|
SET_SYSTEM_SLEEP_PM_OPS(rmi_spi_suspend, rmi_spi_resume) |
|
SET_RUNTIME_PM_OPS(rmi_spi_runtime_suspend, rmi_spi_runtime_resume, |
|
NULL) |
|
}; |
|
|
|
static const struct spi_device_id rmi_id[] = { |
|
{ "rmi4_spi", 0 }, |
|
{ } |
|
}; |
|
MODULE_DEVICE_TABLE(spi, rmi_id); |
|
|
|
static struct spi_driver rmi_spi_driver = { |
|
.driver = { |
|
.name = "rmi4_spi", |
|
.pm = &rmi_spi_pm, |
|
.of_match_table = of_match_ptr(rmi_spi_of_match), |
|
}, |
|
.id_table = rmi_id, |
|
.probe = rmi_spi_probe, |
|
}; |
|
|
|
module_spi_driver(rmi_spi_driver); |
|
|
|
MODULE_AUTHOR("Christopher Heiny <[email protected]>"); |
|
MODULE_AUTHOR("Andrew Duggan <[email protected]>"); |
|
MODULE_DESCRIPTION("RMI SPI driver"); |
|
MODULE_LICENSE("GPL");
|
|
|