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kernel_samsung_a34x-permissive/drivers/misc/mediatek/nfc/st54spi.c
Fede2782 c05564c4d8
Import A346BXXU1AWB9 kernel source 
Android 13
2024-04-28 15:49:01 +02:00

1296 lines
34 KiB
C
Executable file
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/*
* Simple synchronous userspace interface to SPI devices
*
* Copyright (C) 2006 SWAPP
* Andrea Paterniani <a.paterniani@swapp-eng.it>
* Copyright (C) 2007 David Brownell (simplification, cleanup)
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*/
/*
* Modified by ST Microelectronics.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/ioctl.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/compat.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/acpi.h>
#include <linux/pinctrl/consumer.h>
#include <linux/spi/spi.h>
#include <linux/spi/spidev.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/uaccess.h>
#define ST21NFCD_MTK 1
// #define WITH_SPI_CLK_MNGT 1
#ifdef ST21NFCD_MTK
#include <linux/platform_data/spi-mt65xx.h>
#endif // ST21NFCD_MTK
#include "st21nfc/st21nfc.h"
// #ifdef ST21NFCD_MTK
/*
* Define WITH_SPI_CLK_MNGT for integrations
* where the SPI clock needs to be enabled on request
*/
// #define WITH_SPI_CLK_MNGT 1
// #ifdef WITH_SPI_CLK_MNGT
// extern void mt_spi_enable_master_clk(struct spi_device *spidev);
// extern void mt_spi_disable_master_clk(struct spi_device *spidev);
// #endif // WITH_SPI_CLK_MNGT
// #endif //ST21NFCD_MTK
/*
* This supports access to SPI devices using normal userspace I/O calls.
* Note that while traditional UNIX/POSIX I/O semantics are half duplex,
* and often mask message boundaries, full SPI support requires full duplex
* transfers. There are several kinds of internal message boundaries to
* handle chipselect management and other protocol options.
*
* SPI has a character major number assigned. We allocate minor numbers
* dynamically using a bitmask. You must use hotplug tools, such as udev
* (or mdev with busybox) to create and destroy the /dev/st54spi device
* nodes, since there is no fixed association of minor numbers with any
* particular SPI bus or device.
*/
//#define SPIDEV_MAJOR 0 /* dynamic */
static int spidev_major;
#define N_SPI_MINORS 1 /* ... up to 256 */
static DECLARE_BITMAP(minors, N_SPI_MINORS);
#define ST54SPI_IOC_RD_POWER _IOR(SPI_IOC_MAGIC, 99, __u32)
#define ST54SPI_IOC_WR_POWER _IOW(SPI_IOC_MAGIC, 99, __u32)
/* Bit masks for spi_device.mode management. Note that incorrect
* settings for some settings can cause *lots* of trouble for other
* devices on a shared bus:
*
* - CS_HIGH ... this device will be active when it shouldn't be
* - 3WIRE ... when active, it won't behave as it should
* - NO_CS ... there will be no explicit message boundaries; this
* is completely incompatible with the shared bus model
* - READY ... transfers may proceed when they shouldn't.
*
* REVISIT should changing those flags be privileged?
*/
#define SPI_MODE_MASK \
(SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | \
SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP | \
SPI_NO_CS | SPI_READY | SPI_TX_DUAL | \
SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)
struct st54spi_data {
dev_t devt;
spinlock_t spi_lock;
struct spi_device *spi;
struct spi_device *spi_reset;
struct list_head device_entry;
/* TX/RX buffers are NULL unless this device is open (users > 0) */
struct mutex buf_lock;
unsigned int users;
u8 *tx_buffer;
u8 *rx_buffer;
u32 speed_hz;
/* GPIO for SE_POWER_REQ / SE_nRESET */
int power_or_nreset_gpio_mode;
int power_or_nreset_gpio;
int nfcc_needs_poweron;
int sehal_needs_poweron;
int se_is_poweron;
struct pinctrl *pctrl;
struct pinctrl_state *pctrl_mode_spi, *pctrl_mode_idle;
};
#define POWER_MODE_NONE -1
#define POWER_MODE_ST54H 0
#define POWER_MODE_ST54J 1
static LIST_HEAD(device_list);
static DEFINE_MUTEX(device_list_lock);
static unsigned int bufsiz = 4096;
module_param(bufsiz, uint, 0444);
MODULE_PARM_DESC(bufsiz, "data bytes in biggest supported SPI message");
static bool debug_enabled = true;
#define VERBOSE 1
/*-------------------------------------------------------------------------*/
static ssize_t st54spi_sync(
struct st54spi_data *st54spi, struct spi_message *message)
{
DECLARE_COMPLETION_ONSTACK(done);
int status;
struct spi_device *spi;
spin_lock_irq(&st54spi->spi_lock);
spi = st54spi->spi;
spin_unlock_irq(&st54spi->spi_lock);
if (spi == NULL)
status = -ESHUTDOWN;
else
status = spi_sync(spi, message);
if (status == 0)
status = message->actual_length;
return status;
}
static inline ssize_t st54spi_sync_write(
struct st54spi_data *st54spi, size_t len)
{
struct spi_transfer t = {
.tx_buf = st54spi->tx_buffer,
.len = len,
.speed_hz = st54spi->speed_hz,
};
struct spi_message m;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
return st54spi_sync(st54spi, &m);
}
static inline ssize_t st54spi_sync_read(
struct st54spi_data *st54spi, size_t len)
{
struct spi_transfer t = {
.rx_buf = st54spi->rx_buffer,
.len = len,
.speed_hz = st54spi->speed_hz,
};
struct spi_message m;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
return st54spi_sync(st54spi, &m);
}
/*-------------------------------------------------------------------------*/
/* Read-only message with current device setup */
static ssize_t st54spi_read(
struct file *filp, char __user *buf, size_t count, loff_t *f_pos)
{
struct st54spi_data *st54spi;
ssize_t status = 0;
/* chipselect only toggles at start or end of operation */
if (count > bufsiz)
return -EMSGSIZE;
st54spi = filp->private_data;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi Read: %d bytes\n", count);
mutex_lock(&st54spi->buf_lock);
status = st54spi_sync_read(st54spi, count);
if (status > 0) {
unsigned long missing;
missing = copy_to_user(buf, st54spi->rx_buffer, status);
if (missing == status)
status = -EFAULT;
else
status = status - missing;
}
mutex_unlock(&st54spi->buf_lock);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi Read: status: %d\n", status);
return status;
}
/* Write-only message with current device setup */
static ssize_t st54spi_write(
struct file *filp, const char __user *buf, size_t count, loff_t *f_pos)
{
struct st54spi_data *st54spi;
ssize_t status = 0;
unsigned long missing;
/* chipselect only toggles at start or end of operation */
if (count > bufsiz)
return -EMSGSIZE;
st54spi = filp->private_data;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi Write: %d bytes\n", count);
mutex_lock(&st54spi->buf_lock);
missing = copy_from_user(st54spi->tx_buffer, buf, count);
if (missing == 0)
status = st54spi_sync_write(st54spi, count);
else
status = -EFAULT;
mutex_unlock(&st54spi->buf_lock);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi Write: status: %d\n", status);
return status;
}
static int st54spi_message(
struct st54spi_data *st54spi,
struct spi_ioc_transfer *u_xfers,
unsigned int n_xfers)
{
struct spi_message msg;
struct spi_transfer *k_xfers;
struct spi_transfer *k_tmp;
struct spi_ioc_transfer *u_tmp;
unsigned int n, total, tx_total, rx_total;
u8 *tx_buf, *rx_buf;
int status = -EFAULT;
spi_message_init(&msg);
k_xfers = kcalloc(n_xfers, sizeof(*k_tmp), GFP_KERNEL);
if (k_xfers == NULL)
return -ENOMEM;
/* Construct spi_message, copying any tx data to bounce buffer.
* We walk the array of user-provided transfers, using each one
* to initialize a kernel version of the same transfer.
*/
tx_buf = st54spi->tx_buffer;
rx_buf = st54spi->rx_buffer;
total = 0;
tx_total = 0;
rx_total = 0;
for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
n; n--, k_tmp++, u_tmp++) {
k_tmp->len = u_tmp->len;
total += k_tmp->len;
/* Since the function returns the total length of transfers
* on success, restrict the total to positive int values to
* avoid the return value looking like an error. Also check
* each transfer length to avoid arithmetic overflow.
*/
if (total > INT_MAX || k_tmp->len > INT_MAX) {
status = -EMSGSIZE;
goto done;
}
if (u_tmp->rx_buf) {
/* this transfer needs space in RX bounce buffer */
rx_total += k_tmp->len;
if (rx_total > bufsiz) {
status = -EMSGSIZE;
goto done;
}
k_tmp->rx_buf = rx_buf;
if (!access_ok(VERIFY_WRITE,
(u8 __user *)(uintptr_t)u_tmp->rx_buf,
u_tmp->len))
goto done;
rx_buf += k_tmp->len;
}
if (u_tmp->tx_buf) {
/* this transfer needs space in TX bounce buffer */
tx_total += k_tmp->len;
if (tx_total > bufsiz) {
status = -EMSGSIZE;
goto done;
}
k_tmp->tx_buf = tx_buf;
if (copy_from_user(tx_buf,
(const u8 __user *)(uintptr_t)u_tmp->tx_buf,
u_tmp->len))
goto done;
tx_buf += k_tmp->len;
}
k_tmp->cs_change = !!u_tmp->cs_change;
k_tmp->tx_nbits = u_tmp->tx_nbits;
k_tmp->rx_nbits = u_tmp->rx_nbits;
k_tmp->bits_per_word = u_tmp->bits_per_word;
k_tmp->delay_usecs = u_tmp->delay_usecs;
k_tmp->speed_hz = u_tmp->speed_hz;
if (!k_tmp->speed_hz)
k_tmp->speed_hz = st54spi->speed_hz;
#ifdef VERBOSE
dev_dbg(&st54spi->spi->dev, " xfer len %u %s%s%s%dbits %u usec %uHz\n",
u_tmp->len, u_tmp->rx_buf ? "rx " : "", u_tmp->tx_buf ? "tx " : "",
u_tmp->cs_change ? "cs " : "",
u_tmp->bits_per_word ?: st54spi->spi->bits_per_word,
u_tmp->delay_usecs, u_tmp->speed_hz ?: st54spi->spi->max_speed_hz);
#endif
spi_message_add_tail(k_tmp, &msg);
}
status = st54spi_sync(st54spi, &msg);
if (status < 0)
goto done;
/* copy any rx data out of bounce buffer */
rx_buf = st54spi->rx_buffer;
for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) {
if (u_tmp->rx_buf) {
if (__copy_to_user(
(u8 __user *)(uintptr_t)u_tmp->rx_buf,
rx_buf, u_tmp->len)) {
status = -EFAULT;
goto done;
}
rx_buf += u_tmp->len;
}
}
status = total;
done:
kfree(k_xfers);
return status;
}
static struct spi_ioc_transfer *st54spi_get_ioc_message(
unsigned int cmd,
struct spi_ioc_transfer __user *u_ioc,
unsigned int *n_ioc)
{
struct spi_ioc_transfer *ioc;
u32 tmp;
/* Check type, command number and direction */
if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC ||
_IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0)) ||
_IOC_DIR(cmd) != _IOC_WRITE)
return ERR_PTR(-ENOTTY);
tmp = _IOC_SIZE(cmd);
if ((tmp % sizeof(struct spi_ioc_transfer)) != 0)
return ERR_PTR(-EINVAL);
*n_ioc = tmp / sizeof(struct spi_ioc_transfer);
if (*n_ioc == 0)
return NULL;
/* copy into scratch area */
ioc = kmalloc(tmp, GFP_KERNEL);
if (!ioc)
return ERR_PTR(-ENOMEM);
if (__copy_from_user(ioc, u_ioc, tmp)) {
kfree(ioc);
return ERR_PTR(-EFAULT);
}
return ioc;
}
static void st54spi_power_off(struct st54spi_data *st54spi)
{
int ret;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "%s\n", __func__);
// Set NSS pin as highZ (ST54H and ST54J).
// Change NSS polarity to have NSS low.
ret = pinctrl_select_state(st54spi->pctrl, st54spi->pctrl_mode_idle);
if (ret < 0) {
dev_info(&st54spi->spi->dev,
"%s : change NSS management to High Z failed!\n", __func__);
}
// Set SE_PWR_REQ / SE_nRESET to low
if (st54spi->power_or_nreset_gpio)
gpio_set_value(st54spi->power_or_nreset_gpio, 0);
// if ST54H block access to SPI in case this is done during a CLF reset
if (st54spi->power_or_nreset_gpio_mode == POWER_MODE_ST54H) {
// disallow access to SPI r/w
if (st54spi->spi) {
spin_lock_irq(&st54spi->spi_lock);
st54spi->spi_reset = st54spi->spi;
st54spi->spi = NULL;
spin_unlock_irq(&st54spi->spi_lock);
}
// Give time to the CLF to detect falling SE_PWR_REQ
// and pull down the line before continue.
usleep_range(2000, 4500);
}
#ifdef WITH_SPI_CLK_MNGT
// no need for the SPI clock to be enabled.
dev_info(&st54spi->spi->dev, "%s : disabling PMU clock of SPI subsystem\n", __func__);
mt_spi_disable_master_clk(st54spi->spi);
#endif // WITH_SPI_CLK_MNGT
st54spi->se_is_poweron = 0;
}
static void st54spi_power_on(struct st54spi_data *st54spi)
{
int ret;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "%s\n", __func__);
#ifdef WITH_SPI_CLK_MNGT
// the SPI clock needs to be enabled.
dev_info(&st54spi->spi->dev, "%s : enabling PMU clock of SPI subsystem\n", __func__);
mt_spi_enable_master_clk(st54spi->spi);
#endif // WITH_SPI_CLK_MNGT
// set SE_PWR_REQ / SE_nRESET to high and wait for CLF + eSE reaction
if (st54spi->power_or_nreset_gpio) {
gpio_set_value(st54spi->power_or_nreset_gpio, 1);
usleep_range(1000, 1500);
}
// Set NSS pin for the SPI function.
ret = pinctrl_select_state(st54spi->pctrl, st54spi->pctrl_mode_spi);
if (ret < 0) {
dev_info(&st54spi->spi->dev,
"%s : change NSS management to SPI failed!\n", __func__);
}
usleep_range(4000, 5000);
if (st54spi->power_or_nreset_gpio_mode == POWER_MODE_ST54H) {
// re-allow SPI xfers
if (st54spi->spi_reset) {
spin_lock_irq(&st54spi->spi_lock);
st54spi->spi = st54spi->spi_reset;
st54spi->spi_reset = NULL;
spin_unlock_irq(&st54spi->spi_lock);
}
}
st54spi->se_is_poweron = 1;
}
static void st54spi_power_set(struct st54spi_data *st54spi, int val)
{
if (!st54spi)
return;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi sehal pwr_req: %d\n", val);
if (val) {
st54spi->sehal_needs_poweron = 1;
if (st54spi->se_is_poweron == 0)
st54spi_power_on(st54spi);
} else {
st54spi->sehal_needs_poweron = 0;
if ((st54spi->se_is_poweron == 1) &&
(st54spi->nfcc_needs_poweron == 0))
// we don t need power anymore
st54spi_power_off(st54spi);
}
}
static int st54spi_power_get(struct st54spi_data *st54spi)
{
if (st54spi->power_or_nreset_gpio)
return gpio_get_value(st54spi->power_or_nreset_gpio);
return 0;
}
static long st54spi_ioctl(
struct file *filp, unsigned int cmd, unsigned long arg)
{
int err = 0;
int retval = 0;
struct st54spi_data *st54spi;
struct spi_device *spi;
u32 tmp;
unsigned int n_ioc;
struct spi_ioc_transfer *ioc;
/* Check type and command number */
if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC)
return -ENOTTY;
/* Check access direction once here; don't repeat below.
* IOC_DIR is from the user perspective, while access_ok is
* from the kernel perspective; so they look reversed.
*/
if (_IOC_DIR(cmd) & _IOC_READ)
err = !access_ok(VERIFY_WRITE,
(void __user *)arg, _IOC_SIZE(cmd));
if (err == 0 && _IOC_DIR(cmd) & _IOC_WRITE)
err = !access_ok(VERIFY_READ,
(void __user *)arg, _IOC_SIZE(cmd));
if (err)
return -EFAULT;
/* guard against device removal before, or while,
* we issue this ioctl.
*/
st54spi = filp->private_data;
spin_lock_irq(&st54spi->spi_lock);
spi = spi_dev_get(st54spi->spi);
spin_unlock_irq(&st54spi->spi_lock);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi ioctl cmd %d\n", cmd);
if (spi == NULL)
return -ESHUTDOWN;
/* use the buffer lock here for triple duty:
* - prevent I/O (from us) so calling spi_setup() is safe;
* - prevent concurrent SPI_IOC_WR_* from morphing
* data fields while SPI_IOC_RD_* reads them;
* - SPI_IOC_MESSAGE needs the buffer locked "normally".
*/
mutex_lock(&st54spi->buf_lock);
switch (cmd) {
/* read requests */
case SPI_IOC_RD_MODE:
retval = __put_user(
spi->mode & SPI_MODE_MASK, (__u8 __user *)arg);
break;
case SPI_IOC_RD_MODE32:
retval = __put_user(
spi->mode & SPI_MODE_MASK, (__u32 __user *)arg);
break;
case SPI_IOC_RD_LSB_FIRST:
retval = __put_user(
(spi->mode & SPI_LSB_FIRST) ?
1 : 0, (__u8 __user *)arg);
break;
case SPI_IOC_RD_BITS_PER_WORD:
retval = __put_user(
spi->bits_per_word, (__u8 __user *)arg);
break;
case SPI_IOC_RD_MAX_SPEED_HZ:
retval = __put_user(
st54spi->speed_hz, (__u32 __user *)arg);
break;
case ST54SPI_IOC_RD_POWER:
retval = __put_user(
st54spi_power_get(st54spi), (__u32 __user *)arg);
break;
/* write requests */
case SPI_IOC_WR_MODE:
case SPI_IOC_WR_MODE32:
if (cmd == SPI_IOC_WR_MODE)
retval = __get_user(tmp, (u8 __user *)arg);
else
retval = __get_user(tmp, (u32 __user *)arg);
if (retval == 0) {
u32 save = spi->mode;
if (tmp & ~SPI_MODE_MASK) {
retval = -EINVAL;
break;
}
tmp |= spi->mode & ~SPI_MODE_MASK;
spi->mode = (u16)tmp;
retval = spi_setup(spi);
if (retval < 0)
spi->mode = save;
else
dev_dbg(&spi->dev, "spi mode %x\n", tmp);
}
break;
case SPI_IOC_WR_LSB_FIRST:
retval = __get_user(tmp, (__u8 __user *)arg);
if (retval == 0) {
u32 save = spi->mode;
if (tmp)
spi->mode |= SPI_LSB_FIRST;
else
spi->mode &= ~SPI_LSB_FIRST;
retval = spi_setup(spi);
if (retval < 0)
spi->mode = save;
else
dev_dbg(&spi->dev,
"%csb first\n", tmp ?
'l' : 'm');
}
break;
case SPI_IOC_WR_BITS_PER_WORD:
retval = __get_user(tmp, (__u8 __user *)arg);
if (retval == 0) {
u8 save = spi->bits_per_word;
spi->bits_per_word = tmp;
retval = spi_setup(spi);
if (retval < 0)
spi->bits_per_word = save;
else
dev_dbg(&spi->dev, "%d bits per word\n", tmp);
}
break;
case SPI_IOC_WR_MAX_SPEED_HZ:
retval = __get_user(tmp, (__u32 __user *)arg);
if (retval == 0) {
u32 save = spi->max_speed_hz;
spi->max_speed_hz = tmp;
retval = spi_setup(spi);
if (retval >= 0)
st54spi->speed_hz = tmp;
else
dev_dbg(&spi->dev, "%d Hz (max)\n", tmp);
spi->max_speed_hz = save;
}
break;
case ST54SPI_IOC_WR_POWER:
retval = __get_user(tmp, (__u32 __user *)arg);
if (retval == 0) {
st54spi_power_set(st54spi, tmp ? 1 : 0);
dev_dbg(&spi->dev, "SE_POWER_REQ/SE_NRESET set: %d\n", tmp);
}
break;
default:
/* segmented and/or full-duplex I/O request */
/* Check message and copy into scratch area */
ioc = st54spi_get_ioc_message(
cmd, (struct spi_ioc_transfer __user *)arg, &n_ioc);
if (IS_ERR(ioc)) {
retval = PTR_ERR(ioc);
break;
}
if (!ioc)
break; /* n_ioc is also 0 */
/* translate to spi_message, execute */
retval = st54spi_message(st54spi, ioc, n_ioc);
kfree(ioc);
break;
}
mutex_unlock(&st54spi->buf_lock);
spi_dev_put(spi);
if (debug_enabled)
dev_info(&spi->dev, "st54spi ioctl retval %d\n", retval);
return retval;
}
#ifdef CONFIG_COMPAT
static long st54spi_compat_ioc_message(
struct file *filp, unsigned int cmd, unsigned long arg)
{
struct spi_ioc_transfer __user *u_ioc;
int retval = 0;
struct st54spi_data *st54spi;
struct spi_device *spi;
unsigned int n_ioc, n;
struct spi_ioc_transfer *ioc;
u_ioc = (struct spi_ioc_transfer __user *)compat_ptr(arg);
if (!access_ok(VERIFY_READ, u_ioc, _IOC_SIZE(cmd)))
return -EFAULT;
/* guard against device removal before, or while,
* we issue this ioctl.
*/
st54spi = filp->private_data;
spin_lock_irq(&st54spi->spi_lock);
spi = spi_dev_get(st54spi->spi);
spin_unlock_irq(&st54spi->spi_lock);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi compat_ioctl cmd %d\n", cmd);
if (spi == NULL)
return -ESHUTDOWN;
/* SPI_IOC_MESSAGE needs the buffer locked "normally" */
mutex_lock(&st54spi->buf_lock);
/* Check message and copy into scratch area */
ioc = st54spi_get_ioc_message(cmd, u_ioc, &n_ioc);
if (IS_ERR(ioc)) {
retval = PTR_ERR(ioc);
goto done;
}
if (!ioc)
goto done; /* n_ioc is also 0 */
/* Convert buffer pointers */
for (n = 0; n < n_ioc; n++) {
ioc[n].rx_buf = (uintptr_t)compat_ptr(ioc[n].rx_buf);
ioc[n].tx_buf = (uintptr_t)compat_ptr(ioc[n].tx_buf);
}
/* translate to spi_message, execute */
retval = st54spi_message(st54spi, ioc, n_ioc);
kfree(ioc);
done:
mutex_unlock(&st54spi->buf_lock);
spi_dev_put(spi);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi compat_ioctl retval %d\n", retval);
return retval;
}
static long st54spi_compat_ioctl(
struct file *filp, unsigned int cmd, unsigned long arg)
{
if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC &&
_IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0)) &&
_IOC_DIR(cmd) == _IOC_WRITE)
return st54spi_compat_ioc_message(filp, cmd, arg);
return st54spi_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#else
#define st54spi_compat_ioctl NULL
#endif /* CONFIG_COMPAT */
static int st54spi_open(struct inode *inode, struct file *filp)
{
struct st54spi_data *st54spi;
int status = -ENXIO;
mutex_lock(&device_list_lock);
list_for_each_entry(st54spi, &device_list, device_entry) {
if (st54spi->devt == inode->i_rdev) {
status = 0;
break;
}
}
if (status) {
dev_dbg(&st54spi->spi->dev, "st54spi: nothing for minor %d\n", iminor(inode));
goto err_find_dev;
}
// Authorize only 1 process to open the device.
if (st54spi->users > 0) {
dev_info(&st54spi->spi->dev, "%d: already open\n");
mutex_unlock(&device_list_lock);
return -EBUSY;
}
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi: open\n");
if (!st54spi->tx_buffer) {
st54spi->tx_buffer = kmalloc(bufsiz, GFP_KERNEL);
if (!st54spi->tx_buffer) {
// dev_dbg(&st54spi->spi->dev, "open/ENOMEM\n");
status = -ENOMEM;
goto err_find_dev;
}
}
if (!st54spi->rx_buffer) {
st54spi->rx_buffer = kmalloc(bufsiz, GFP_KERNEL);
if (!st54spi->rx_buffer) {
// dev_dbg(&st54spi->spi->dev, "open/ENOMEM\n");
status = -ENOMEM;
goto err_alloc_rx_buf;
}
}
st54spi->users++;
filp->private_data = st54spi;
nonseekable_open(inode, filp);
mutex_unlock(&device_list_lock);
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi: open - force power on\n");
st54spi_power_set(st54spi, 1);
return 0;
err_alloc_rx_buf:
kfree(st54spi->tx_buffer);
st54spi->tx_buffer = NULL;
err_find_dev:
mutex_unlock(&device_list_lock);
return status;
}
static int st54spi_release(struct inode *inode, struct file *filp)
{
struct st54spi_data *st54spi;
mutex_lock(&device_list_lock);
st54spi = filp->private_data;
filp->private_data = NULL;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi: release\n");
/* last close? */
st54spi->users--;
if (!st54spi->users) {
int dofree;
if (debug_enabled)
dev_info(&st54spi->spi->dev, "st54spi: release - may allow power off\n");
st54spi_power_set(st54spi, 0);
kfree(st54spi->tx_buffer);
st54spi->tx_buffer = NULL;
kfree(st54spi->rx_buffer);
st54spi->rx_buffer = NULL;
spin_lock_irq(&st54spi->spi_lock);
if (st54spi->spi)
st54spi->speed_hz = st54spi->spi->max_speed_hz;
/* ... after we unbound from the underlying device? */
dofree = ((st54spi->spi == NULL) &&
(st54spi->spi_reset == NULL));
spin_unlock_irq(&st54spi->spi_lock);
if (dofree)
kfree(st54spi);
}
mutex_unlock(&device_list_lock);
return 0;
}
static const struct file_operations st54spi_fops = {
.owner = THIS_MODULE,
/* REVISIT switch to aio primitives, so that userspace
* gets more complete API coverage. It'll simplify things
* too, except for the locking.
*/
.write = st54spi_write,
.read = st54spi_read,
.unlocked_ioctl = st54spi_ioctl,
.compat_ioctl = st54spi_compat_ioctl,
.open = st54spi_open,
.release = st54spi_release,
.llseek = no_llseek,
};
/*-------------------------------------------------------------------------*/
/* The main reason to have this class is to make mdev/udev create the
* /dev/st54spi character device nodes exposing our userspace API.
* It also simplifies memory management.
*/
static struct class *st54spi_class;
static const struct of_device_id st54spi_dt_ids[] = {
{.compatible = "st,st54spi"},
{},
};
MODULE_DEVICE_TABLE(of, st54spi_dt_ids);
#ifdef CONFIG_ACPI
/* Dummy SPI devices not to be used in production systems */
#define SPIDEV_ACPI_DUMMY 1
static const struct acpi_device_id st54spi_acpi_ids[] = {
/*
* The ACPI SPT000* devices are only meant for development and
* testing. Systems used in production should have a proper ACPI
* description of the connected peripheral and they should also use
* a proper driver instead of poking directly to the SPI bus.
*/
{"SPT0001", SPIDEV_ACPI_DUMMY},
{"SPT0002", SPIDEV_ACPI_DUMMY},
{"SPT0003", SPIDEV_ACPI_DUMMY},
{},
};
MODULE_DEVICE_TABLE(acpi, st54spi_acpi_ids);
static void st54spi_probe_acpi(struct spi_device *spi)
{
const struct acpi_device_id *id;
if (!has_acpi_companion(&spi->dev))
return;
id = acpi_match_device(st54spi_acpi_ids, &spi->dev);
if (WARN_ON(!id))
return;
}
#else
static inline void st54spi_probe_acpi(struct spi_device *spi) {}
#endif
/*-------------------------------------------------------------------------*/
static int st54spi_parse_dt(struct device *dev, struct st54spi_data *pdata)
{
int r = 0;
struct device_node *np = dev->of_node;
np = of_find_compatible_node(NULL, NULL, "st,st54spi");
if (np) {
const char *power_mode;
#if (!defined(CONFIG_MTK_GPIO) || defined(CONFIG_MTK_GPIOLIB_STAND))
r = of_get_named_gpio(np, "gpio-power_nreset-std", 0);
if (r < 0)
dev_info(dev, "%s: get ST54 failed (%d)", __FILE__, r);
else
pdata->power_or_nreset_gpio = r;
r = 0;
#else
of_property_read_u32_array(
np, "gpio-power_nreset", &(pdata->power_or_nreset_gpio), 1);
#endif
// Read power mode.
power_mode = of_get_property(np, "power_mode", NULL);
if (!power_mode) {
dev_info(dev, "%s: Default power mode: ST54H\n", __FILE__);
pdata->power_or_nreset_gpio_mode = POWER_MODE_ST54H;
} else if (!strcmp(power_mode, "ST54J")) {
dev_info(dev, "%s: Power mode: ST54J\n", __FILE__);
pdata->power_or_nreset_gpio_mode = POWER_MODE_ST54J;
} else if (!strcmp(power_mode, "ST54H")) {
dev_info(dev, "%s: Power mode: ST54H\n", __FILE__);
pdata->power_or_nreset_gpio_mode = POWER_MODE_ST54H;
} else if (!strcmp(power_mode, "none")) {
dev_info(dev, "%s: Power mode: none\n", __FILE__);
pdata->power_or_nreset_gpio_mode = POWER_MODE_NONE;
} else {
dev_info(dev, "%s: Power mode unknown: %s\n", __FILE__, power_mode);
return -1;
}
} else {
dev_info(dev, "%s : get num err.\n", __func__);
return -1;
}
// We need to use pinmux to control NSS
pdata->pctrl = devm_pinctrl_get(dev);
if (IS_ERR(pdata->pctrl)) {
dev_info(dev, "%s: Unable to allocate pinctrl: %d\n",
__FILE__, PTR_ERR(pdata->pctrl));
return -1;
}
pdata->pctrl_mode_spi = pinctrl_lookup_state(pdata->pctrl, "pinctrl_state_mode_spi");
if (IS_ERR(pdata->pctrl_mode_spi)) {
dev_info(dev, "%s: Unable to find pinctrl_state_mode_spi: %d\n",
__FILE__, PTR_ERR(pdata->pctrl_mode_spi));
return -1;
}
pdata->pctrl_mode_idle = pinctrl_lookup_state(pdata->pctrl, "pinctrl_state_mode_idle");
if (IS_ERR(pdata->pctrl_mode_idle)) {
dev_info(dev, "%s: Unable to find pinctrl_state_mode_idle: %d\n",
__FILE__, PTR_ERR(pdata->pctrl_mode_idle));
return -1;
}
dev_info(dev, "[dsc]%s : pinctrl initialized\n", __func__);
dev_info(dev, "[dsc]%s : get power_or_nreset_gpio[%d]\n",
__func__, pdata->power_or_nreset_gpio);
return r;
}
#ifndef MODULE
static void st54spi_st21nfc_cb(int dir, void *data)
{
struct st54spi_data *st54spi = (struct st54spi_data *)data;
if (!st54spi)
return;
dev_info(&st54spi->spi->dev, "%s : dir %d data %p\n", __func__, dir, st54spi);
switch (dir) {
case ST54SPI_CB_RESET_START:
if (st54spi->se_is_poweron)
st54spi_power_off(st54spi);
break;
case ST54SPI_CB_RESET_END:
// wait for the CLF to boot once nRESET is released
usleep_range(4000, 8000);
st54spi_power_on(st54spi);
break;
case ST54SPI_CB_ESE_USED:
st54spi->nfcc_needs_poweron = 1;
if (st54spi->se_is_poweron == 0)
st54spi_power_on(st54spi);
break;
case ST54SPI_CB_ESE_NOT_USED:
st54spi->nfcc_needs_poweron = 0;
if ((st54spi->se_is_poweron == 1) &&
(st54spi->sehal_needs_poweron == 0))
// we don t need power anymore
st54spi_power_off(st54spi);
break;
}
}
#endif // !MODULE
/* Change CS_TIME for ST54 */
#ifdef ST21NFCD_MTK
// Unit is 1/109.2 us.
static struct mtk_chip_config st54spi_chip_info = {
.cs_setuptime = 2184, // 20 us
};
#endif
static int st54spi_probe(struct spi_device *spi)
{
struct st54spi_data *st54spi;
int status, ret;
unsigned long minor;
#ifdef ST21NFCD_MTK
struct mtk_chip_config *chip_config = spi->controller_data;
#endif
/*
* st54spi should never be referenced in DT without a specific
* compatible string, it is a Linux implementation thing
* rather than a description of the hardware.
*/
st54spi_probe_acpi(spi);
/* Allocate driver data */
st54spi = kzalloc(sizeof(*st54spi), GFP_KERNEL);
if (!st54spi)
return -ENOMEM;
/* Initialize the driver data */
st54spi->spi = spi;
spin_lock_init(&st54spi->spi_lock);
mutex_init(&st54spi->buf_lock);
INIT_LIST_HEAD(&st54spi->device_entry);
/* If we can allocate a minor number, hook up this device.
* Reusing minors is fine so long as udev or mdev is working.
*/
mutex_lock(&device_list_lock);
minor = find_first_zero_bit(minors, N_SPI_MINORS);
if (minor < N_SPI_MINORS) {
struct device *dev;
st54spi->devt = MKDEV(spidev_major, minor);
dev = device_create(st54spi_class, &spi->dev, st54spi->devt,
// spidev, "spidev%d.%d",
// spi->master->bus_num, spi->chip_select);
st54spi, "st54spi");
status = PTR_ERR_OR_ZERO(dev);
} else {
dev_dbg(&spi->dev, "no minor number available!\n");
status = -ENODEV;
}
if (status == 0) {
set_bit(minor, minors);
list_add(&st54spi->device_entry, &device_list);
}
mutex_unlock(&device_list_lock);
st54spi->speed_hz = spi->max_speed_hz;
dev_dbg(&spi->dev, "st54spi->speed_hz=%d\n", st54spi->speed_hz);
// {
// /* fixed SPI clock speed: 109200000 */
// int period = DIV_ROUND_UP(109200000, st54spi->speed_hz);
// st54spi_chip_info.cs_idletime = period;
// st54spi_chip_info.cs_holdtime = period;
// }
#ifdef ST21NFCD_MTK
// set timings for ST54
if (chip_config == NULL) {
spi->controller_data = (void *)&st54spi_chip_info;
dev_dbg(&spi->dev, "Replaced chip_info!\n");
} else {
chip_config->cs_setuptime = st54spi_chip_info.cs_setuptime;
chip_config->cs_idletime = st54spi_chip_info.cs_idletime;
chip_config->cs_holdtime = st54spi_chip_info.cs_holdtime;
dev_dbg(&spi->dev, "Added into chip_info!\n");
}
#else
dev_info(&spi->dev, "%s : TSU_NSS configuration be implemented!\n", __func__);
// platform-specific method to configure the delay beween NSS slave
// selection and the start of data transfer (clk).
// If no specific method required, you can comment above line.
#endif
if (status == 0)
spi_set_drvdata(spi, st54spi);
else
kfree(st54spi);
(void)st54spi_parse_dt(&spi->dev, st54spi);
if (st54spi->power_or_nreset_gpio != 0) {
int default_value = 0;
ret = gpio_request(st54spi->power_or_nreset_gpio,
#if (!defined(CONFIG_MTK_GPIO) || defined(CONFIG_MTK_GPIOLIB_STAND))
"gpio-power_nreset-std"
#else
"gpio-power_nreset"
#endif
);
if (ret)
dev_info(&spi->dev, "%s : power request failed (%d)\n",
__FILE__, ret);
dev_info(&spi->dev, "%s : power/nreset GPIO = %d\n", __func__,
st54spi->power_or_nreset_gpio);
ret = gpio_direction_output(st54spi->power_or_nreset_gpio, default_value);
if (ret)
dev_info(&spi->dev, "%s : reset direction_output failed\n", __FILE__);
/* active high */
gpio_set_value(st54spi->power_or_nreset_gpio, default_value);
}
if (st54spi->power_or_nreset_gpio_mode == POWER_MODE_ST54H) {
#ifndef MODULE
dev_info(&spi->dev, "%s : Register with st21nfc driver, %p\n",
__func__, st54spi);
st21nfc_register_st54spi_cb(st54spi_st21nfc_cb, st54spi);
#else
dev_info(&spi->dev, "%s : st54spi as module cannot use ST54H fully\n",
__func__);
#endif
}
return status;
}
static int st54spi_remove(struct spi_device *spi)
{
struct st54spi_data *st54spi = spi_get_drvdata(spi);
if (st54spi->power_or_nreset_gpio_mode == POWER_MODE_ST54H) {
#ifndef MODULE
dev_info(&st54spi->spi->dev, "%s : Unregister from st21nfc driver\n",
__func__);
st21nfc_unregister_st54spi_cb();
#endif
}
/* make sure ops on existing fds can abort cleanly */
spin_lock_irq(&st54spi->spi_lock);
st54spi->spi = NULL;
st54spi->spi_reset = NULL;
spin_unlock_irq(&st54spi->spi_lock);
/* prevent new opens */
mutex_lock(&device_list_lock);
list_del(&st54spi->device_entry);
device_destroy(st54spi_class, st54spi->devt);
clear_bit(MINOR(st54spi->devt), minors);
if (st54spi->users == 0)
kfree(st54spi);
mutex_unlock(&device_list_lock);
return 0;
}
static struct spi_driver st54spi_spi_driver = {
.driver = {
.name = "st54spi",
.of_match_table = of_match_ptr(st54spi_dt_ids),
.acpi_match_table = ACPI_PTR(st54spi_acpi_ids),
},
.probe = st54spi_probe,
.remove = st54spi_remove,
/* NOTE: suspend/resume methods are not necessary here.
* We don't do anything except pass the requests to/from
* the underlying controller. The refrigerator handles
* most issues; the controller driver handles the rest.
*/
};
/*-------------------------------------------------------------------------*/
static int __init st54spi_init(void)
{
int status;
pr_info("Loading st54spi driver\n");
/* Claim our 256 reserved device numbers. Then register a class
* that will key udev/mdev to add/remove /dev nodes. Last, register
* the driver which manages those device numbers.
*/
BUILD_BUG_ON(N_SPI_MINORS > 256);
spidev_major = __register_chrdev(0, 0, N_SPI_MINORS,
"spi", &st54spi_fops);
pr_info("Loading st54spi driver, major: %d\n", spidev_major);
st54spi_class = class_create(THIS_MODULE, "spidev");
if (IS_ERR(st54spi_class)) {
unregister_chrdev(spidev_major, st54spi_spi_driver.driver.name);
return PTR_ERR(st54spi_class);
}
status = spi_register_driver(&st54spi_spi_driver);
if (status < 0) {
class_destroy(st54spi_class);
unregister_chrdev(spidev_major, st54spi_spi_driver.driver.name);
}
pr_info("Loading st54spi driver: %d\n", status);
return status;
}
module_init(st54spi_init);
static void __exit st54spi_exit(void)
{
spi_unregister_driver(&st54spi_spi_driver);
class_destroy(st54spi_class);
unregister_chrdev(spidev_major, st54spi_spi_driver.driver.name);
}
module_exit(st54spi_exit);
MODULE_AUTHOR("Andrea Paterniani, <a.paterniani@swapp-eng.it>");
MODULE_DESCRIPTION("User mode SPI device interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:st54spi");
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