From 7df3fd261b529e6f0c5939870d79b16065d7c0c4 Mon Sep 17 00:00:00 2001 From: zhuangnk1 Date: Mon, 28 Jun 2021 16:23:53 +0800 Subject: [PATCH] Rogue PRC ST54x driver Add ST54x driver for Rogue PRC ese bring up Change-Id: I8b49bc09ce96eaf3fdb18bc8398629cba1b76d23 Signed-off-by: zhuangnk1 Reviewed-on: https://gerrit.mot.com/1993975 SLTApproved: Slta Waiver SME-Granted: SME Approvals Granted Tested-by: Jira Key Reviewed-by: Zishang Zhou Reviewed-by: Tao Sun Submit-Approved: Jira Key --- drivers/ese/st54x/Android.mk | 8 + drivers/ese/st54x/Kbuild | 6 + drivers/ese/st54x/Makefile | 16 + drivers/ese/st54x/st54spi.c | 1226 ++++++++++++++++++++++++++++++++++ 4 files changed, 1256 insertions(+) create mode 100644 drivers/ese/st54x/Android.mk create mode 100644 drivers/ese/st54x/Kbuild create mode 100644 drivers/ese/st54x/Makefile create mode 100644 drivers/ese/st54x/st54spi.c diff --git a/drivers/ese/st54x/Android.mk b/drivers/ese/st54x/Android.mk new file mode 100644 index 000000000000..dd11c6fbda9c --- /dev/null +++ b/drivers/ese/st54x/Android.mk @@ -0,0 +1,8 @@ +DLKM_DIR := motorola/kernel/modules +LOCAL_PATH := $(call my-dir) + +include $(CLEAR_VARS) +LOCAL_MODULE := st54spi.ko +LOCAL_MODULE_TAGS := optional +LOCAL_MODULE_PATH := $(KERNEL_MODULES_OUT) +include $(DLKM_DIR)/AndroidKernelModule.mk diff --git a/drivers/ese/st54x/Kbuild b/drivers/ese/st54x/Kbuild new file mode 100644 index 000000000000..54f720126045 --- /dev/null +++ b/drivers/ese/st54x/Kbuild @@ -0,0 +1,6 @@ +# add -Wall to try to catch everything we can. +EXTRA_CFLAGS += -Wall +EXTRA_CFLAGS += -I$(ANDROID_BUILD_TOP)/motorola/kernel/modules/include + +obj-m += st54spi.o + diff --git a/drivers/ese/st54x/Makefile b/drivers/ese/st54x/Makefile new file mode 100644 index 000000000000..918721816043 --- /dev/null +++ b/drivers/ese/st54x/Makefile @@ -0,0 +1,16 @@ +all: modules + +modules: + $(MAKE) -C $(KERNEL_SRC) M=$(M) modules $(KBUILD_OPTIONS) + +modules_install: + $(MAKE) INSTALL_MOD_STRIP=1 -C $(KERNEL_SRC) M=$(M) modules_install + +%: + $(MAKE) -C $(KERNEL_SRC) M=$(M) $@ $(KBUILD_OPTIONS) + +clean: + rm -f *.o *.ko *.mod.c *.mod.o *~ .*.cmd Module.symvers + rm -rf .tmp_versions + + diff --git a/drivers/ese/st54x/st54spi.c b/drivers/ese/st54x/st54spi.c new file mode 100644 index 000000000000..ddf93e14bab5 --- /dev/null +++ b/drivers/ese/st54x/st54spi.c @@ -0,0 +1,1226 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Simple synchronous userspace interface to SPI devices + * Copyright (C) 2020 ST Microelectronics S.A. + * Copyright (C) 2006 SWAPP Andrea Paterniani + * Copyright (C) 2007 David Brownell (simplification, cleanup) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include + +#include + +// #define WITH_SPI_CLK_MNGT 1 + +#include "linux/st21nfc.h" + + +/* + * 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: %zu 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: %zd\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: %zu 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: %zd\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((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_err(&st54spi->spi->dev, + "%s : change CSB 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); + } + + + 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__); + + // 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_err(&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((void __user *)arg, _IOC_SIZE(cmd)); + if (err == 0 && _IOC_DIR(cmd) & _IOC_WRITE) + err = !access_ok((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(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_err(&st54spi->spi->dev, "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; + 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; + + // 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_err(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_err(dev, "%s: Unable to allocate pinctrl: %ld\n", + __FILE__, PTR_ERR(pdata->pctrl)); + return -1; + } + + pdata->pctrl_mode_spi = pinctrl_lookup_state(pdata->pctrl, "spi_active"); + if (IS_ERR(pdata->pctrl_mode_spi)) { + dev_err(dev, "%s: Unable to find qupv3_se12_spi_active: %ld\n", + __FILE__, PTR_ERR(pdata->pctrl_mode_spi)); + return -1; + } + + pdata->pctrl_mode_idle = pinctrl_lookup_state(pdata->pctrl, "spi_sleep"); + if (IS_ERR(pdata->pctrl_mode_idle)) { + dev_err(dev, "%s: Unable to find qupv3_se12_spi_sleep: %ld\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 */ + +static struct spi_delay st54spi_delay = { + .unit = SPI_DELAY_UNIT_USECS, + .value = 10, +}; + +static int st54spi_probe(struct spi_device *spi) +{ + struct st54spi_data *st54spi; + int status, ret; + unsigned long minor; + + /* + * 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; + // } + + // this method exists since kernel 5.3 + // it uses u8 parameter in kernel 5.4 (clk count) and spi_delay parameter in kernel 5.5 (clk_count fobidden) + // target 10us delay ==> use CLK=4MHz and value 31 (even if u8 data, some platforms limit to 0-31) + spi_set_cs_timing(spi, &st54spi_delay, NULL, NULL); + + 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, + "gpio-power_nreset-std" + ); + 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_err(&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, "eSE"); + 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, "); +MODULE_DESCRIPTION("User mode SPI device interface"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:st54spi");