- 根目录:
- drivers
- spi
- spi-dln2.c
/*
* Driver for the Diolan DLN-2 USB-SPI adapter
*
* Copyright (c) 2014 Intel Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mfd/dln2.h>
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
#include <asm/unaligned.h>
#define DLN2_SPI_MODULE_ID 0x02
#define DLN2_SPI_CMD(cmd) DLN2_CMD(cmd, DLN2_SPI_MODULE_ID)
/* SPI commands */
#define DLN2_SPI_GET_PORT_COUNT DLN2_SPI_CMD(0x00)
#define DLN2_SPI_ENABLE DLN2_SPI_CMD(0x11)
#define DLN2_SPI_DISABLE DLN2_SPI_CMD(0x12)
#define DLN2_SPI_IS_ENABLED DLN2_SPI_CMD(0x13)
#define DLN2_SPI_SET_MODE DLN2_SPI_CMD(0x14)
#define DLN2_SPI_GET_MODE DLN2_SPI_CMD(0x15)
#define DLN2_SPI_SET_FRAME_SIZE DLN2_SPI_CMD(0x16)
#define DLN2_SPI_GET_FRAME_SIZE DLN2_SPI_CMD(0x17)
#define DLN2_SPI_SET_FREQUENCY DLN2_SPI_CMD(0x18)
#define DLN2_SPI_GET_FREQUENCY DLN2_SPI_CMD(0x19)
#define DLN2_SPI_READ_WRITE DLN2_SPI_CMD(0x1A)
#define DLN2_SPI_READ DLN2_SPI_CMD(0x1B)
#define DLN2_SPI_WRITE DLN2_SPI_CMD(0x1C)
#define DLN2_SPI_SET_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x20)
#define DLN2_SPI_GET_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x21)
#define DLN2_SPI_SET_DELAY_AFTER_SS DLN2_SPI_CMD(0x22)
#define DLN2_SPI_GET_DELAY_AFTER_SS DLN2_SPI_CMD(0x23)
#define DLN2_SPI_SET_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x24)
#define DLN2_SPI_GET_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x25)
#define DLN2_SPI_SET_SS DLN2_SPI_CMD(0x26)
#define DLN2_SPI_GET_SS DLN2_SPI_CMD(0x27)
#define DLN2_SPI_RELEASE_SS DLN2_SPI_CMD(0x28)
#define DLN2_SPI_SS_VARIABLE_ENABLE DLN2_SPI_CMD(0x2B)
#define DLN2_SPI_SS_VARIABLE_DISABLE DLN2_SPI_CMD(0x2C)
#define DLN2_SPI_SS_VARIABLE_IS_ENABLED DLN2_SPI_CMD(0x2D)
#define DLN2_SPI_SS_AAT_ENABLE DLN2_SPI_CMD(0x2E)
#define DLN2_SPI_SS_AAT_DISABLE DLN2_SPI_CMD(0x2F)
#define DLN2_SPI_SS_AAT_IS_ENABLED DLN2_SPI_CMD(0x30)
#define DLN2_SPI_SS_BETWEEN_FRAMES_ENABLE DLN2_SPI_CMD(0x31)
#define DLN2_SPI_SS_BETWEEN_FRAMES_DISABLE DLN2_SPI_CMD(0x32)
#define DLN2_SPI_SS_BETWEEN_FRAMES_IS_ENABLED DLN2_SPI_CMD(0x33)
#define DLN2_SPI_SET_CPHA DLN2_SPI_CMD(0x34)
#define DLN2_SPI_GET_CPHA DLN2_SPI_CMD(0x35)
#define DLN2_SPI_SET_CPOL DLN2_SPI_CMD(0x36)
#define DLN2_SPI_GET_CPOL DLN2_SPI_CMD(0x37)
#define DLN2_SPI_SS_MULTI_ENABLE DLN2_SPI_CMD(0x38)
#define DLN2_SPI_SS_MULTI_DISABLE DLN2_SPI_CMD(0x39)
#define DLN2_SPI_SS_MULTI_IS_ENABLED DLN2_SPI_CMD(0x3A)
#define DLN2_SPI_GET_SUPPORTED_MODES DLN2_SPI_CMD(0x40)
#define DLN2_SPI_GET_SUPPORTED_CPHA_VALUES DLN2_SPI_CMD(0x41)
#define DLN2_SPI_GET_SUPPORTED_CPOL_VALUES DLN2_SPI_CMD(0x42)
#define DLN2_SPI_GET_SUPPORTED_FRAME_SIZES DLN2_SPI_CMD(0x43)
#define DLN2_SPI_GET_SS_COUNT DLN2_SPI_CMD(0x44)
#define DLN2_SPI_GET_MIN_FREQUENCY DLN2_SPI_CMD(0x45)
#define DLN2_SPI_GET_MAX_FREQUENCY DLN2_SPI_CMD(0x46)
#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x47)
#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_SS DLN2_SPI_CMD(0x48)
#define DLN2_SPI_GET_MIN_DELAY_AFTER_SS DLN2_SPI_CMD(0x49)
#define DLN2_SPI_GET_MAX_DELAY_AFTER_SS DLN2_SPI_CMD(0x4A)
#define DLN2_SPI_GET_MIN_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x4B)
#define DLN2_SPI_GET_MAX_DELAY_BETWEEN_FRAMES DLN2_SPI_CMD(0x4C)
#define DLN2_SPI_MAX_XFER_SIZE 256
#define DLN2_SPI_BUF_SIZE (DLN2_SPI_MAX_XFER_SIZE + 16)
#define DLN2_SPI_ATTR_LEAVE_SS_LOW BIT(0)
#define DLN2_TRANSFERS_WAIT_COMPLETE 1
#define DLN2_TRANSFERS_CANCEL 0
#define DLN2_RPM_AUTOSUSPEND_TIMEOUT 2000
struct dln2_spi {
struct platform_device *pdev;
struct spi_master *master;
u8 port;
/*
* This buffer will be used mainly for read/write operations. Since
* they're quite large, we cannot use the stack. Protection is not
* needed because all SPI communication is serialized by the SPI core.
*/
void *buf;
u8 bpw;
u32 speed;
u16 mode;
u8 cs;
};
/*
* Enable/Disable SPI module. The disable command will wait for transfers to
* complete first.
*/
static int dln2_spi_enable(struct dln2_spi *dln2, bool enable)
{
u16 cmd;
struct {
u8 port;
u8 wait_for_completion;
} tx;
unsigned len = sizeof(tx);
tx.port = dln2->port;
if (enable) {
cmd = DLN2_SPI_ENABLE;
len -= sizeof(tx.wait_for_completion);
} else {
tx.wait_for_completion = DLN2_TRANSFERS_WAIT_COMPLETE;
cmd = DLN2_SPI_DISABLE;
}
return dln2_transfer_tx(dln2->pdev, cmd, &tx, len);
}
/*
* Select/unselect multiple CS lines. The selected lines will be automatically
* toggled LOW/HIGH by the board firmware during transfers, provided they're
* enabled first.
*
* Ex: cs_mask = 0x03 -> CS0 & CS1 will be selected and the next WR/RD operation
* will toggle the lines LOW/HIGH automatically.
*/
static int dln2_spi_cs_set(struct dln2_spi *dln2, u8 cs_mask)
{
struct {
u8 port;
u8 cs;
} tx;
tx.port = dln2->port;
/*
* According to Diolan docs, "a slave device can be selected by changing
* the corresponding bit value to 0". The rest must be set to 1. Hence
* the bitwise NOT in front.
*/
tx.cs = ~cs_mask;
return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_SS, &tx, sizeof(tx));
}
/*
* Select one CS line. The other lines will be un-selected.
*/
static int dln2_spi_cs_set_one(struct dln2_spi *dln2, u8 cs)
{
return dln2_spi_cs_set(dln2, BIT(cs));
}
/*
* Enable/disable CS lines for usage. The module has to be disabled first.
*/
static int dln2_spi_cs_enable(struct dln2_spi *dln2, u8 cs_mask, bool enable)
{
struct {
u8 port;
u8 cs;
} tx;
u16 cmd;
tx.port = dln2->port;
tx.cs = cs_mask;
cmd = enable ? DLN2_SPI_SS_MULTI_ENABLE : DLN2_SPI_SS_MULTI_DISABLE;
return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx));
}
static int dln2_spi_cs_enable_all(struct dln2_spi *dln2, bool enable)
{
u8 cs_mask = GENMASK(dln2->master->num_chipselect - 1, 0);
return dln2_spi_cs_enable(dln2, cs_mask, enable);
}
static int dln2_spi_get_cs_num(struct dln2_spi *dln2, u16 *cs_num)
{
int ret;
struct {
u8 port;
} tx;
struct {
__le16 cs_count;
} rx;
unsigned rx_len = sizeof(rx);
tx.port = dln2->port;
ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SS_COUNT, &tx, sizeof(tx),
&rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(rx))
return -EPROTO;
*cs_num = le16_to_cpu(rx.cs_count);
dev_dbg(&dln2->pdev->dev, "cs_num = %d\n", *cs_num);
return 0;
}
static int dln2_spi_get_speed(struct dln2_spi *dln2, u16 cmd, u32 *freq)
{
int ret;
struct {
u8 port;
} tx;
struct {
__le32 speed;
} rx;
unsigned rx_len = sizeof(rx);
tx.port = dln2->port;
ret = dln2_transfer(dln2->pdev, cmd, &tx, sizeof(tx), &rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(rx))
return -EPROTO;
*freq = le32_to_cpu(rx.speed);
return 0;
}
/*
* Get bus min/max frequencies.
*/
static int dln2_spi_get_speed_range(struct dln2_spi *dln2, u32 *fmin, u32 *fmax)
{
int ret;
ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MIN_FREQUENCY, fmin);
if (ret < 0)
return ret;
ret = dln2_spi_get_speed(dln2, DLN2_SPI_GET_MAX_FREQUENCY, fmax);
if (ret < 0)
return ret;
dev_dbg(&dln2->pdev->dev, "freq_min = %d, freq_max = %d\n",
*fmin, *fmax);
return 0;
}
/*
* Set the bus speed. The module will automatically round down to the closest
* available frequency and returns it. The module has to be disabled first.
*/
static int dln2_spi_set_speed(struct dln2_spi *dln2, u32 speed)
{
int ret;
struct {
u8 port;
__le32 speed;
} __packed tx;
struct {
__le32 speed;
} rx;
int rx_len = sizeof(rx);
tx.port = dln2->port;
tx.speed = cpu_to_le32(speed);
ret = dln2_transfer(dln2->pdev, DLN2_SPI_SET_FREQUENCY, &tx, sizeof(tx),
&rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(rx))
return -EPROTO;
return 0;
}
/*
* Change CPOL & CPHA. The module has to be disabled first.
*/
static int dln2_spi_set_mode(struct dln2_spi *dln2, u8 mode)
{
struct {
u8 port;
u8 mode;
} tx;
tx.port = dln2->port;
tx.mode = mode;
return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_MODE, &tx, sizeof(tx));
}
/*
* Change frame size. The module has to be disabled first.
*/
static int dln2_spi_set_bpw(struct dln2_spi *dln2, u8 bpw)
{
struct {
u8 port;
u8 bpw;
} tx;
tx.port = dln2->port;
tx.bpw = bpw;
return dln2_transfer_tx(dln2->pdev, DLN2_SPI_SET_FRAME_SIZE,
&tx, sizeof(tx));
}
static int dln2_spi_get_supported_frame_sizes(struct dln2_spi *dln2,
u32 *bpw_mask)
{
int ret;
struct {
u8 port;
} tx;
struct {
u8 count;
u8 frame_sizes[36];
} *rx = dln2->buf;
unsigned rx_len = sizeof(*rx);
int i;
tx.port = dln2->port;
ret = dln2_transfer(dln2->pdev, DLN2_SPI_GET_SUPPORTED_FRAME_SIZES,
&tx, sizeof(tx), rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(*rx))
return -EPROTO;
if (rx->count > ARRAY_SIZE(rx->frame_sizes))
return -EPROTO;
*bpw_mask = 0;
for (i = 0; i < rx->count; i++)
*bpw_mask |= BIT(rx->frame_sizes[i] - 1);
dev_dbg(&dln2->pdev->dev, "bpw_mask = 0x%X\n", *bpw_mask);
return 0;
}
/*
* Copy the data to DLN2 buffer and change the byte order to LE, requested by
* DLN2 module. SPI core makes sure that the data length is a multiple of word
* size.
*/
static int dln2_spi_copy_to_buf(u8 *dln2_buf, const u8 *src, u16 len, u8 bpw)
{
#ifdef __LITTLE_ENDIAN
memcpy(dln2_buf, src, len);
#else
if (bpw <= 8) {
memcpy(dln2_buf, src, len);
} else if (bpw <= 16) {
__le16 *d = (__le16 *)dln2_buf;
u16 *s = (u16 *)src;
len = len / 2;
while (len--)
*d++ = cpu_to_le16p(s++);
} else {
__le32 *d = (__le32 *)dln2_buf;
u32 *s = (u32 *)src;
len = len / 4;
while (len--)
*d++ = cpu_to_le32p(s++);
}
#endif
return 0;
}
/*
* Copy the data from DLN2 buffer and convert to CPU byte order since the DLN2
* buffer is LE ordered. SPI core makes sure that the data length is a multiple
* of word size. The RX dln2_buf is 2 byte aligned so, for BE, we have to make
* sure we avoid unaligned accesses for 32 bit case.
*/
static int dln2_spi_copy_from_buf(u8 *dest, const u8 *dln2_buf, u16 len, u8 bpw)
{
#ifdef __LITTLE_ENDIAN
memcpy(dest, dln2_buf, len);
#else
if (bpw <= 8) {
memcpy(dest, dln2_buf, len);
} else if (bpw <= 16) {
u16 *d = (u16 *)dest;
__le16 *s = (__le16 *)dln2_buf;
len = len / 2;
while (len--)
*d++ = le16_to_cpup(s++);
} else {
u32 *d = (u32 *)dest;
__le32 *s = (__le32 *)dln2_buf;
len = len / 4;
while (len--)
*d++ = get_unaligned_le32(s++);
}
#endif
return 0;
}
/*
* Perform one write operation.
*/
static int dln2_spi_write_one(struct dln2_spi *dln2, const u8 *data,
u16 data_len, u8 attr)
{
struct {
u8 port;
__le16 size;
u8 attr;
u8 buf[DLN2_SPI_MAX_XFER_SIZE];
} __packed *tx = dln2->buf;
unsigned tx_len;
BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE);
if (data_len > DLN2_SPI_MAX_XFER_SIZE)
return -EINVAL;
tx->port = dln2->port;
tx->size = cpu_to_le16(data_len);
tx->attr = attr;
dln2_spi_copy_to_buf(tx->buf, data, data_len, dln2->bpw);
tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE;
return dln2_transfer_tx(dln2->pdev, DLN2_SPI_WRITE, tx, tx_len);
}
/*
* Perform one read operation.
*/
static int dln2_spi_read_one(struct dln2_spi *dln2, u8 *data,
u16 data_len, u8 attr)
{
int ret;
struct {
u8 port;
__le16 size;
u8 attr;
} __packed tx;
struct {
__le16 size;
u8 buf[DLN2_SPI_MAX_XFER_SIZE];
} __packed *rx = dln2->buf;
unsigned rx_len = sizeof(*rx);
BUILD_BUG_ON(sizeof(*rx) > DLN2_SPI_BUF_SIZE);
if (data_len > DLN2_SPI_MAX_XFER_SIZE)
return -EINVAL;
tx.port = dln2->port;
tx.size = cpu_to_le16(data_len);
tx.attr = attr;
ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ, &tx, sizeof(tx),
rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(rx->size) + data_len)
return -EPROTO;
if (le16_to_cpu(rx->size) != data_len)
return -EPROTO;
dln2_spi_copy_from_buf(data, rx->buf, data_len, dln2->bpw);
return 0;
}
/*
* Perform one write & read operation.
*/
static int dln2_spi_read_write_one(struct dln2_spi *dln2, const u8 *tx_data,
u8 *rx_data, u16 data_len, u8 attr)
{
int ret;
struct {
u8 port;
__le16 size;
u8 attr;
u8 buf[DLN2_SPI_MAX_XFER_SIZE];
} __packed *tx;
struct {
__le16 size;
u8 buf[DLN2_SPI_MAX_XFER_SIZE];
} __packed *rx;
unsigned tx_len, rx_len;
BUILD_BUG_ON(sizeof(*tx) > DLN2_SPI_BUF_SIZE ||
sizeof(*rx) > DLN2_SPI_BUF_SIZE);
if (data_len > DLN2_SPI_MAX_XFER_SIZE)
return -EINVAL;
/*
* Since this is a pseudo full-duplex communication, we're perfectly
* safe to use the same buffer for both tx and rx. When DLN2 sends the
* response back, with the rx data, we don't need the tx buffer anymore.
*/
tx = dln2->buf;
rx = dln2->buf;
tx->port = dln2->port;
tx->size = cpu_to_le16(data_len);
tx->attr = attr;
dln2_spi_copy_to_buf(tx->buf, tx_data, data_len, dln2->bpw);
tx_len = sizeof(*tx) + data_len - DLN2_SPI_MAX_XFER_SIZE;
rx_len = sizeof(*rx);
ret = dln2_transfer(dln2->pdev, DLN2_SPI_READ_WRITE, tx, tx_len,
rx, &rx_len);
if (ret < 0)
return ret;
if (rx_len < sizeof(rx->size) + data_len)
return -EPROTO;
if (le16_to_cpu(rx->size) != data_len)
return -EPROTO;
dln2_spi_copy_from_buf(rx_data, rx->buf, data_len, dln2->bpw);
return 0;
}
/*
* Read/Write wrapper. It will automatically split an operation into multiple
* single ones due to device buffer constraints.
*/
static int dln2_spi_rdwr(struct dln2_spi *dln2, const u8 *tx_data,
u8 *rx_data, u16 data_len, u8 attr) {
int ret;
u16 len;
u8 temp_attr;
u16 remaining = data_len;
u16 offset;
do {
if (remaining > DLN2_SPI_MAX_XFER_SIZE) {
len = DLN2_SPI_MAX_XFER_SIZE;
temp_attr = DLN2_SPI_ATTR_LEAVE_SS_LOW;
} else {
len = remaining;
temp_attr = attr;
}
offset = data_len - remaining;
if (tx_data && rx_data) {
ret = dln2_spi_read_write_one(dln2,
tx_data + offset,
rx_data + offset,
len, temp_attr);
} else if (tx_data) {
ret = dln2_spi_write_one(dln2,
tx_data + offset,
len, temp_attr);
} else if (rx_data) {
ret = dln2_spi_read_one(dln2,
rx_data + offset,
len, temp_attr);
} else {
return -EINVAL;
}
if (ret < 0)
return ret;
remaining -= len;
} while (remaining);
return 0;
}
static int dln2_spi_prepare_message(struct spi_master *master,
struct spi_message *message)
{
int ret;
struct dln2_spi *dln2 = spi_master_get_devdata(master);
struct spi_device *spi = message->spi;
if (dln2->cs != spi->chip_select) {
ret = dln2_spi_cs_set_one(dln2, spi->chip_select);
if (ret < 0)
return ret;
dln2->cs = spi->chip_select;
}
return 0;
}
static int dln2_spi_transfer_setup(struct dln2_spi *dln2, u32 speed,
u8 bpw, u8 mode)
{
int ret;
bool bus_setup_change;
bus_setup_change = dln2->speed != speed || dln2->mode != mode ||
dln2->bpw != bpw;
if (!bus_setup_change)
return 0;
ret = dln2_spi_enable(dln2, false);
if (ret < 0)
return ret;
if (dln2->speed != speed) {
ret = dln2_spi_set_speed(dln2, speed);
if (ret < 0)
return ret;
dln2->speed = speed;
}
if (dln2->mode != mode) {
ret = dln2_spi_set_mode(dln2, mode & 0x3);
if (ret < 0)
return ret;
dln2->mode = mode;
}
if (dln2->bpw != bpw) {
ret = dln2_spi_set_bpw(dln2, bpw);
if (ret < 0)
return ret;
dln2->bpw = bpw;
}
return dln2_spi_enable(dln2, true);
}
static int dln2_spi_transfer_one(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
struct dln2_spi *dln2 = spi_master_get_devdata(master);
int status;
u8 attr = 0;
status = dln2_spi_transfer_setup(dln2, xfer->speed_hz,
xfer->bits_per_word,
spi->mode);
if (status < 0) {
dev_err(&dln2->pdev->dev, "Cannot setup transfer\n");
return status;
}
if (!xfer->cs_change && !spi_transfer_is_last(master, xfer))
attr = DLN2_SPI_ATTR_LEAVE_SS_LOW;
status = dln2_spi_rdwr(dln2, xfer->tx_buf, xfer->rx_buf,
xfer->len, attr);
if (status < 0)
dev_err(&dln2->pdev->dev, "write/read failed!\n");
return status;
}
static int dln2_spi_probe(struct platform_device *pdev)
{
struct spi_master *master;
struct dln2_spi *dln2;
struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev);
int ret;
master = spi_alloc_master(&pdev->dev, sizeof(*dln2));
if (!master)
return -ENOMEM;
platform_set_drvdata(pdev, master);
dln2 = spi_master_get_devdata(master);
dln2->buf = devm_kmalloc(&pdev->dev, DLN2_SPI_BUF_SIZE, GFP_KERNEL);
if (!dln2->buf) {
ret = -ENOMEM;
goto exit_free_master;
}
dln2->master = master;
dln2->pdev = pdev;
dln2->port = pdata->port;
/* cs/mode can never be 0xff, so the first transfer will set them */
dln2->cs = 0xff;
dln2->mode = 0xff;
/* disable SPI module before continuing with the setup */
ret = dln2_spi_enable(dln2, false);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to disable SPI module\n");
goto exit_free_master;
}
ret = dln2_spi_get_cs_num(dln2, &master->num_chipselect);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to get number of CS pins\n");
goto exit_free_master;
}
ret = dln2_spi_get_speed_range(dln2,
&master->min_speed_hz,
&master->max_speed_hz);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to read bus min/max freqs\n");
goto exit_free_master;
}
ret = dln2_spi_get_supported_frame_sizes(dln2,
&master->bits_per_word_mask);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to read supported frame sizes\n");
goto exit_free_master;
}
ret = dln2_spi_cs_enable_all(dln2, true);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to enable CS pins\n");
goto exit_free_master;
}
master->bus_num = -1;
master->mode_bits = SPI_CPOL | SPI_CPHA;
master->prepare_message = dln2_spi_prepare_message;
master->transfer_one = dln2_spi_transfer_one;
master->auto_runtime_pm = true;
/* enable SPI module, we're good to go */
ret = dln2_spi_enable(dln2, true);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to enable SPI module\n");
goto exit_free_master;
}
pm_runtime_set_autosuspend_delay(&pdev->dev,
DLN2_RPM_AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
ret = devm_spi_register_master(&pdev->dev, master);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to register master\n");
goto exit_register;
}
return ret;
exit_register:
pm_runtime_disable(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
if (dln2_spi_enable(dln2, false) < 0)
dev_err(&pdev->dev, "Failed to disable SPI module\n");
exit_free_master:
spi_master_put(master);
return ret;
}
static int dln2_spi_remove(struct platform_device *pdev)
{
struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
struct dln2_spi *dln2 = spi_master_get_devdata(master);
pm_runtime_disable(&pdev->dev);
if (dln2_spi_enable(dln2, false) < 0)
dev_err(&pdev->dev, "Failed to disable SPI module\n");
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int dln2_spi_suspend(struct device *dev)
{
int ret;
struct spi_master *master = dev_get_drvdata(dev);
struct dln2_spi *dln2 = spi_master_get_devdata(master);
ret = spi_master_suspend(master);
if (ret < 0)
return ret;
if (!pm_runtime_suspended(dev)) {
ret = dln2_spi_enable(dln2, false);
if (ret < 0)
return ret;
}
/*
* USB power may be cut off during sleep. Resetting the following
* parameters will force the board to be set up before first transfer.
*/
dln2->cs = 0xff;
dln2->speed = 0;
dln2->bpw = 0;
dln2->mode = 0xff;
return 0;
}
static int dln2_spi_resume(struct device *dev)
{
int ret;
struct spi_master *master = dev_get_drvdata(dev);
struct dln2_spi *dln2 = spi_master_get_devdata(master);
if (!pm_runtime_suspended(dev)) {
ret = dln2_spi_cs_enable_all(dln2, true);
if (ret < 0)
return ret;
ret = dln2_spi_enable(dln2, true);
if (ret < 0)
return ret;
}
return spi_master_resume(master);
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM
static int dln2_spi_runtime_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct dln2_spi *dln2 = spi_master_get_devdata(master);
return dln2_spi_enable(dln2, false);
}
static int dln2_spi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct dln2_spi *dln2 = spi_master_get_devdata(master);
return dln2_spi_enable(dln2, true);
}
#endif /* CONFIG_PM */
static const struct dev_pm_ops dln2_spi_pm = {
SET_SYSTEM_SLEEP_PM_OPS(dln2_spi_suspend, dln2_spi_resume)
SET_RUNTIME_PM_OPS(dln2_spi_runtime_suspend,
dln2_spi_runtime_resume, NULL)
};
static struct platform_driver spi_dln2_driver = {
.driver = {
.name = "dln2-spi",
.pm = &dln2_spi_pm,
},
.probe = dln2_spi_probe,
.remove = dln2_spi_remove,
};
module_platform_driver(spi_dln2_driver);
MODULE_DESCRIPTION("Driver for the Diolan DLN2 SPI master interface");
MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:dln2-spi");