This is a driver for the PN544 Near Field Communication (NFC) device. The driver mainly transfers ETSI Single Wire Protocol (SWP) messages between the device and the userspace. Signed-off-by: Matti J. Aaltonen <matti.j.aaltonen@xxxxxxxxx> --- Documentation/nfc/nfc-pn544.txt | 117 +++++ drivers/Kconfig | 2 + drivers/Makefile | 2 +- drivers/nfc/Kconfig | 30 ++ drivers/nfc/Makefile | 5 + drivers/nfc/pn544.c | 891 +++++++++++++++++++++++++++++++++++++++ include/linux/nfc/pn544.h | 97 +++++ 7 files changed, 1143 insertions(+), 1 deletions(-) create mode 100644 Documentation/nfc/nfc-pn544.txt create mode 100644 drivers/nfc/Kconfig create mode 100644 drivers/nfc/Makefile create mode 100644 drivers/nfc/pn544.c create mode 100644 include/linux/nfc/pn544.h diff --git a/Documentation/nfc/nfc-pn544.txt b/Documentation/nfc/nfc-pn544.txt new file mode 100644 index 0000000..d4fc351 --- /dev/null +++ b/Documentation/nfc/nfc-pn544.txt @@ -0,0 +1,117 @@ + + + + +Kernel driver for the NXP Semiconductors PN544 Near Field Communication chip + +Author: Jari Vanhala +Contact: Matti Aaltonen (matti.j.aaltonen at nokia.com) + +General +------- + +The PN544 is an integrated transmission module for contactless +communication. The driver goes under drives/nfc/ and is compiled as a +module named "pn544". It registers a misc device and creates a device +file named "/dev/pn544". + +Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C. + +The Interface +------------- + +The driver offers a sysfs interface for a hardware test and an IOCTL +interface for selecting between two operating modes. There are read, +write and poll functions for transferring messages. The two operating +modes are the normal (HCI) mode and the firmware update mode. + +PN544 is controlled by sending messages from the userspace to the +chip. The main function of the driver is just to pass those messages +without caring about the message content. + + +Protocols +--------- + +In the normal (HCI) mode and in the firmware update mode read and +write functions behave a bit differently because the message formats +or the protocols are different. + +In the normal (HCI) mode the protocol used is derived from the ETSI +Single Wire Protocol (SWP) specification. The firmware is updated +using a specific protocol, which is different from HCI. + +HCI messages consist of an eight bit header and the message body. The +header contains the message length. Maximum size for an HCI message is +33. In HCI mode sent messages are tested for a correct +checksum. Firmware update messages have the length in the second (MSB) +and third (LSB) bytes of the message. The maximum FW message length is +1024 bytes. + +For the ETSI SWP specification see +http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx + +The Hardware Test +----------------- + +The idea of the test is that it can performed by reading from the +corresponding sysfs file. The test is implemented in the board file +and it should test that PN544 can be put into the firmware update +mode. If the test is not implemented the sysfs file does not get +created. + +Example: +> cat /sys/module/pn544/drivers/i2c\:pn544/3-002b/nfc_test +1 + +Normal Operation +---------------- + +PN544 is powered up when the device file is opened, otherwise it's +turned off. Only one instance can use the device at a time. + +Userspace applications control PN544 with HCI messages. The hardware +sends an interrupt when data is available for reading. Data is +physically read when the read function is called by a userspace +application. Poll() checks the read interrupt state. Configuration and +self testing are also done from the userspace using read and write. + +Example platform data: + +static int rx71_pn544_nfc_request_resources(struct i2c_client *client) +{ + /* Get and setup the HW resources for the device */ +} + +static void rx71_pn544_nfc_free_resources(void) +{ + /* Release the HW resources */ +} + +static void rx71_pn544_nfc_enable(int fw) +{ + /* Turn the device on */ +} + +static int rx71_pn544_nfc_test(void) +{ + /* + * Put the device into the FW update mode + * and then back to the normal mode. + * Check the behavior and return one on success, + * zero on failure. + */ +} + +static void rx71_pn544_nfc_disable(void) +{ + /* turn the power off */ +} + +static struct pn544_nfc_platform_data rx71_nfc_data = { + .request_resources = rx71_pn544_nfc_request_resources, + .free_resources = rx71_pn544_nfc_free_resources, + .enable = rx71_pn544_nfc_enable, + .test = rx71_pn544_nfc_test, + .disable = rx71_pn544_nfc_disable, +}; diff --git a/drivers/Kconfig b/drivers/Kconfig index a2b902f..d7f27d6 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -111,4 +111,6 @@ source "drivers/xen/Kconfig" source "drivers/staging/Kconfig" source "drivers/platform/Kconfig" + +source "drivers/nfc/Kconfig" endmenu diff --git a/drivers/Makefile b/drivers/Makefile index a2aea53..a6705ff 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -39,7 +39,7 @@ obj-$(CONFIG_FB_INTEL) += video/intelfb/ obj-y += serial/ obj-$(CONFIG_PARPORT) += parport/ -obj-y += base/ block/ misc/ mfd/ +obj-y += base/ block/ misc/ mfd/ nfc/ obj-$(CONFIG_NUBUS) += nubus/ obj-y += macintosh/ obj-$(CONFIG_IDE) += ide/ diff --git a/drivers/nfc/Kconfig b/drivers/nfc/Kconfig new file mode 100644 index 0000000..ffedfd4 --- /dev/null +++ b/drivers/nfc/Kconfig @@ -0,0 +1,30 @@ +# +# Near Field Communication (NFC) devices +# + +menuconfig NFC_DEVICES + bool "NFC devices" + default n + ---help--- + You'll have to say Y if your computer contains an NFC device that + you want to use under Linux. + + You can say N here if you don't have any Near Field Communication + devices connected to your computer. + +if NFC_DEVICES + +config PN544_NFC + tristate "PN544 NFC driver" + depends on I2C + select CRC_CCITT + default n + ---help--- + Say yes if you want PN544 Near Field Communication driver. + This is for i2c connected version. If unsure, say N here. + + To compile this driver as a module, choose m here. The module will + be called pn544. + + +endif # NFC_DEVICES diff --git a/drivers/nfc/Makefile b/drivers/nfc/Makefile new file mode 100644 index 0000000..a4efb16 --- /dev/null +++ b/drivers/nfc/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for nfc devices +# + +obj-$(CONFIG_PN544_NFC) += pn544.o diff --git a/drivers/nfc/pn544.c b/drivers/nfc/pn544.c new file mode 100644 index 0000000..401c44b --- /dev/null +++ b/drivers/nfc/pn544.c @@ -0,0 +1,891 @@ +/* + * Driver for the PN544 NFC chip. + * + * Copyright (C) Nokia Corporation + * + * Author: Jari Vanhala <ext-jari.vanhala@xxxxxxxxx> + * Contact: Matti Aaltonen <matti.j.aaltonen@xxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/completion.h> +#include <linux/crc-ccitt.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/nfc/pn544.h> +#include <linux/poll.h> +#include <linux/regulator/consumer.h> +#include <linux/serial_core.h> /* for TCGETS */ +#include <linux/slab.h> + +#define DRIVER_CARD "PN544 NFC" +#define DRIVER_DESC "NFC driver for PN544" + +static struct i2c_device_id pn544_id_table[] = { + { PN544_DRIVER_NAME, 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pn544_id_table); + +#define HCI_MODE 0 +#define FW_MODE 1 + +enum pn544_state { + PN544_ST_COLD, + PN544_ST_FW_READY, + PN544_ST_READY, +}; + +enum pn544_irq { + PN544_NONE, + PN544_INT, +}; + +struct pn544_info { + struct miscdevice miscdev; + struct i2c_client *i2c_dev; + struct regulator_bulk_data regs[2]; + + enum pn544_state state; + wait_queue_head_t read_wait; + loff_t read_offset; + enum pn544_irq read_irq; + struct mutex read_mutex; /* Serialize read_irq access */ + struct mutex mutex; /* Serialize info struct access */ + u8 *buf; + unsigned int buflen; +}; + +static const char reg_vdd_io[] = "Vdd_IO"; +static const char reg_vbat[] = "VBat"; + +/* sysfs interface */ +static ssize_t pn544_test(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pn544_info *info = dev_get_drvdata(dev); + struct i2c_client *client = info->i2c_dev; + struct pn544_nfc_platform_data *pdata = client->dev.platform_data; + + return snprintf(buf, PAGE_SIZE, "%d\n", pdata->test()); +} + +static int pn544_enable(struct pn544_info *info, int mode) +{ + struct pn544_nfc_platform_data *pdata; + struct i2c_client *client = info->i2c_dev; + + int r; + + r = regulator_bulk_enable(ARRAY_SIZE(info->regs), info->regs); + if (r < 0) + return r; + + pdata = client->dev.platform_data; + info->read_irq = PN544_NONE; + if (pdata->enable) + pdata->enable(mode); + + if (mode) { + info->state = PN544_ST_FW_READY; + dev_dbg(&client->dev, "now in FW-mode\n"); + } else { + info->state = PN544_ST_READY; + dev_dbg(&client->dev, "now in HCI-mode\n"); + } + + usleep_range(10000, 15000); + + return 0; +} + +static void pn544_disable(struct pn544_info *info) +{ + struct pn544_nfc_platform_data *pdata; + struct i2c_client *client = info->i2c_dev; + + pdata = client->dev.platform_data; + if (pdata->disable) + pdata->disable(); + + info->state = PN544_ST_COLD; + + dev_dbg(&client->dev, "Now in OFF-mode\n"); + + msleep(PN544_RESETVEN_TIME); + + info->read_irq = PN544_NONE; + regulator_bulk_disable(ARRAY_SIZE(info->regs), info->regs); +} + +static int check_crc(u8 *buf, int buflen) +{ + u8 len; + u16 crc; + + len = buf[0] + 1; + if (len < 4 || len != buflen || len > PN544_MSG_MAX_SIZE) { + pr_err(PN544_DRIVER_NAME + ": CRC; corrupt packet len %u (%d)\n", len, buflen); + print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, + 16, 2, buf, buflen, false); + return -EPERM; + } + crc = crc_ccitt(0xffff, buf, len - 2); + crc = ~crc; + + if (buf[len-2] != (crc & 0xff) || buf[len-1] != (crc >> 8)) { + pr_err(PN544_DRIVER_NAME ": CRC error 0x%x != 0x%x 0x%x\n", + crc, buf[len-1], buf[len-2]); + + print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, + 16, 2, buf, buflen, false); + return -EPERM; + } + return 0; +} + +static int pn544_i2c_write(struct i2c_client *client, u8 *buf, int len) +{ + int r; + + if (len < 4 || len != (buf[0] + 1)) { + dev_err(&client->dev, "%s: Illegal message length: %d\n", + __func__, len); + return -EINVAL; + } + + if (check_crc(buf, len)) + return -EINVAL; + + usleep_range(3000, 6000); + + r = i2c_master_send(client, buf, len); + dev_dbg(&client->dev, "send: %d\n", r); + + if (r == -EREMOTEIO) { /* Retry, chip was in standby */ + usleep_range(6000, 10000); + r = i2c_master_send(client, buf, len); + dev_dbg(&client->dev, "send2: %d\n", r); + } + + if (r != len) + return -EREMOTEIO; + + return r; +} + +static int pn544_i2c_read(struct i2c_client *client, u8 *buf, int buflen) +{ + int r; + u8 len; + + /* + * You could read a packet in one go, but then you'd need to read + * max size and rest would be 0xff fill, so we do split reads. + */ + r = i2c_master_recv(client, &len, 1); + dev_dbg(&client->dev, "recv1: %d\n", r); + + if (r != 1) + return -EREMOTEIO; + + if (len < PN544_LLC_HCI_OVERHEAD) + len = PN544_LLC_HCI_OVERHEAD; + else if (len > (PN544_MSG_MAX_SIZE - 1)) + len = PN544_MSG_MAX_SIZE - 1; + + if (1 + len > buflen) /* len+(data+crc16) */ + return -EMSGSIZE; + + buf[0] = len; + + r = i2c_master_recv(client, buf + 1, len); + dev_dbg(&client->dev, "recv2: %d\n", r); + + if (r != len) + return -EREMOTEIO; + + usleep_range(3000, 6000); + + return r + 1; +} + +static int pn544_fw_write(struct i2c_client *client, u8 *buf, int len) +{ + int r; + + dev_dbg(&client->dev, "%s\n", __func__); + + if (len < PN544_FW_HEADER_SIZE || + (PN544_FW_HEADER_SIZE + (buf[1] << 8) + buf[2]) != len) + return -EINVAL; + + r = i2c_master_send(client, buf, len); + dev_dbg(&client->dev, "fw send: %d\n", r); + + if (r == -EREMOTEIO) { /* Retry, chip was in standby */ + usleep_range(6000, 10000); + r = i2c_master_send(client, buf, len); + dev_dbg(&client->dev, "fw send2: %d\n", r); + } + + if (r != len) + return -EREMOTEIO; + + return r; +} + +static int pn544_fw_read(struct i2c_client *client, u8 *buf, int buflen) +{ + int r, len; + + if (buflen < PN544_FW_HEADER_SIZE) + return -EINVAL; + + r = i2c_master_recv(client, buf, PN544_FW_HEADER_SIZE); + dev_dbg(&client->dev, "FW recv1: %d\n", r); + + if (r < 0) + return r; + + if (r < PN544_FW_HEADER_SIZE) + return -EINVAL; + + len = (buf[1] << 8) + buf[2]; + if (len == 0) /* just header, no additional data */ + return r; + + if (len > buflen - PN544_FW_HEADER_SIZE) + return -EMSGSIZE; + + r = i2c_master_recv(client, buf + PN544_FW_HEADER_SIZE, len); + dev_dbg(&client->dev, "fw recv2: %d\n", r); + + if (r != len) + return -EINVAL; + + return r + PN544_FW_HEADER_SIZE; +} + +static irqreturn_t pn544_irq_thread_fn(int irq, void *dev_id) +{ + struct pn544_info *info = dev_id; + struct i2c_client *client = info->i2c_dev; + + BUG_ON(!info); + BUG_ON(irq != info->i2c_dev->irq); + + dev_dbg(&client->dev, "IRQ\n"); + + mutex_lock(&info->read_mutex); + info->read_irq = PN544_INT; + mutex_unlock(&info->read_mutex); + + wake_up_interruptible(&info->read_wait); + + return IRQ_HANDLED; +} + +static enum pn544_irq pn544_irq_state(struct pn544_info *info) +{ + enum pn544_irq irq; + + mutex_lock(&info->read_mutex); + irq = info->read_irq; + mutex_unlock(&info->read_mutex); + /* + * XXX: should we check GPIO-line status directly? + * return pdata->irq_status() ? PN544_INT : PN544_NONE; + */ + + return irq; +} + +static ssize_t pn544_read(struct file *file, char __user *buf, + size_t count, loff_t *offset) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + enum pn544_irq irq; + size_t len; + int r = 0; + + dev_dbg(&client->dev, "%s: info: %p, count: %zu\n", __func__, + info, count); + + mutex_lock(&info->mutex); + + if (info->state == PN544_ST_COLD) { + r = -ENODEV; + goto out; + } + + irq = pn544_irq_state(info); + if (irq == PN544_NONE) { + if (file->f_flags & O_NONBLOCK) { + r = -EAGAIN; + goto out; + } + + if (wait_event_interruptible(info->read_wait, + (info->read_irq == PN544_INT))) { + r = -ERESTARTSYS; + goto out; + } + } + + if (info->state == PN544_ST_FW_READY) { + len = min(count, info->buflen); + + mutex_lock(&info->read_mutex); + r = pn544_fw_read(info->i2c_dev, info->buf, len); + info->read_irq = PN544_NONE; + mutex_unlock(&info->read_mutex); + + if (r < 0) { + dev_err(&info->i2c_dev->dev, "FW read failed: %d\n", r); + goto out; + } + + print_hex_dump(KERN_DEBUG, "FW read: ", DUMP_PREFIX_NONE, + 16, 2, info->buf, r, false); + + *offset += r; + if (copy_to_user(buf, info->buf, r)) { + r = -EFAULT; + goto out; + } + } else { + len = min(count, info->buflen); + + mutex_lock(&info->read_mutex); + r = pn544_i2c_read(info->i2c_dev, info->buf, len); + info->read_irq = PN544_NONE; + mutex_unlock(&info->read_mutex); + + if (r < 0) { + dev_err(&info->i2c_dev->dev, "read failed (%d)\n", r); + goto out; + } + print_hex_dump(KERN_DEBUG, "read: ", DUMP_PREFIX_NONE, + 16, 2, info->buf, r, false); + + *offset += r; + if (copy_to_user(buf, info->buf, r)) { + r = -EFAULT; + goto out; + } + } + +out: + mutex_unlock(&info->mutex); + + return r; +} + +static unsigned int pn544_poll(struct file *file, poll_table *wait) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + int r = 0; + + dev_dbg(&client->dev, "%s: info: %p\n", __func__, info); + + mutex_lock(&info->mutex); + + if (info->state == PN544_ST_COLD) { + r = -ENODEV; + goto out; + } + + poll_wait(file, &info->read_wait, wait); + + if (pn544_irq_state(info) == PN544_INT) { + r = POLLIN | POLLRDNORM; + goto out; + } +out: + mutex_unlock(&info->mutex); + + return r; +} + +static ssize_t pn544_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + ssize_t len; + int r; + + dev_dbg(&client->dev, "%s: info: %p, count %zu\n", __func__, + info, count); + + mutex_lock(&info->mutex); + + if (info->state == PN544_ST_COLD) { + r = -ENODEV; + goto out; + } + + /* + * XXX: should we detect rset-writes and clean possible + * read_irq state + */ + if (info->state == PN544_ST_FW_READY) { + size_t fw_len; + + if (count < PN544_FW_HEADER_SIZE) { + r = -EINVAL; + goto out; + } + + len = min(count, info->buflen); + if (copy_from_user(info->buf, buf, len)) { + r = -EFAULT; + goto out; + } + + print_hex_dump(KERN_DEBUG, "FW write: ", DUMP_PREFIX_NONE, + 16, 2, info->buf, len, false); + + fw_len = PN544_FW_HEADER_SIZE + (info->buf[1] << 8) + + info->buf[2]; + + if (len > fw_len) /* 1 msg at a time */ + len = fw_len; + + r = pn544_fw_write(info->i2c_dev, info->buf, len); + } else { + if (count < PN544_LLC_MIN_SIZE) { + r = -EINVAL; + goto out; + } + + len = min(count, info->buflen); + if (copy_from_user(info->buf, buf, len)) { + r = -EFAULT; + goto out; + } + + print_hex_dump(KERN_DEBUG, "write: ", DUMP_PREFIX_NONE, + 16, 2, info->buf, len, false); + + if (len > (info->buf[0] + 1)) /* 1 msg at a time */ + len = info->buf[0] + 1; + + r = pn544_i2c_write(info->i2c_dev, info->buf, len); + } +out: + mutex_unlock(&info->mutex); + + return r; + +} + +static long pn544_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + struct pn544_nfc_platform_data *pdata; + unsigned int val; + int r = 0; + + dev_dbg(&client->dev, "%s: info: %p, cmd: 0x%x\n", __func__, info, cmd); + + mutex_lock(&info->mutex); + + if (info->state == PN544_ST_COLD) { + r = -ENODEV; + goto out; + } + + pdata = info->i2c_dev->dev.platform_data; + switch (cmd) { + case PN544_GET_FW_MODE: + dev_dbg(&client->dev, "%s: PN544_GET_FW_MODE\n", __func__); + + val = (info->state == PN544_ST_FW_READY); + if (copy_to_user((void __user *)arg, &val, sizeof(val))) { + r = -EFAULT; + goto out; + } + + break; + + case PN544_SET_FW_MODE: + dev_dbg(&client->dev, "%s: PN544_SET_FW_MODE\n", __func__); + + if (copy_from_user(&val, (void __user *)arg, sizeof(val))) { + r = -EFAULT; + goto out; + } + + if (val) { + if (info->state == PN544_ST_FW_READY) + break; + + pn544_disable(info); + r = pn544_enable(info, FW_MODE); + if (r < 0) + goto out; + } else { + if (info->state == PN544_ST_READY) + break; + pn544_disable(info); + r = pn544_enable(info, HCI_MODE); + if (r < 0) + goto out; + } + file->f_pos = info->read_offset; + break; + + case TCGETS: + dev_dbg(&client->dev, "%s: TCGETS\n", __func__); + + r = -ENOIOCTLCMD; + break; + + default: + dev_err(&client->dev, "Unknown ioctl 0x%x\n", cmd); + r = -ENOIOCTLCMD; + break; + } + +out: + mutex_unlock(&info->mutex); + + return r; +} + +static int pn544_open(struct inode *inode, struct file *file) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + int r = 0; + + dev_dbg(&client->dev, "%s: info: %p, client %p\n", __func__, + info, info->i2c_dev); + + mutex_lock(&info->mutex); + + /* + * Only 1 at a time. + * XXX: maybe user (counter) would work better + */ + if (info->state != PN544_ST_COLD) { + r = -EBUSY; + goto out; + } + + file->f_pos = info->read_offset; + r = pn544_enable(info, HCI_MODE); + +out: + mutex_unlock(&info->mutex); + return r; +} + +static int pn544_close(struct inode *inode, struct file *file) +{ + struct pn544_info *info = container_of(file->private_data, + struct pn544_info, miscdev); + struct i2c_client *client = info->i2c_dev; + + dev_dbg(&client->dev, "%s: info: %p, client %p\n", + __func__, info, info->i2c_dev); + + mutex_lock(&info->mutex); + pn544_disable(info); + mutex_unlock(&info->mutex); + + return 0; +} + +static const struct file_operations pn544_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = pn544_read, + .write = pn544_write, + .poll = pn544_poll, + .open = pn544_open, + .release = pn544_close, + .unlocked_ioctl = pn544_ioctl, +}; + +#ifdef CONFIG_PM +static int pn544_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct pn544_info *info; + int r = 0; + + dev_info(&client->dev, "***\n%s: client %p\n***\n", __func__, client); + + info = i2c_get_clientdata(client); + dev_info(&client->dev, "%s: info: %p, client %p\n", __func__, + info, client); + + mutex_lock(&info->mutex); + + switch (info->state) { + case PN544_ST_FW_READY: + /* Do not suspend while upgrading FW, please! */ + r = -EPERM; + break; + + case PN544_ST_READY: + /* + * CHECK: Device should be in standby-mode. No way to check? + * Allowing low power mode for the regulator is potentially + * dangerous if pn544 does not go to suspension. + */ + break; + + case PN544_ST_COLD: + break; + }; + + mutex_unlock(&info->mutex); + return r; +} + +static int pn544_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct pn544_info *info = i2c_get_clientdata(client); + int r = 0; + + dev_dbg(&client->dev, "%s: info: %p, client %p\n", __func__, + info, client); + + mutex_lock(&info->mutex); + + switch (info->state) { + case PN544_ST_READY: + /* + * CHECK: If regulator low power mode is allowed in + * pn544_suspend, we should go back to normal mode + * here. + */ + break; + + case PN544_ST_COLD: + break; + + case PN544_ST_FW_READY: + break; + }; + + mutex_unlock(&info->mutex); + + return r; +} + +static SIMPLE_DEV_PM_OPS(pn544_pm_ops, pn544_suspend, pn544_resume); +#endif + +static struct device_attribute pn544_attr = + __ATTR(nfc_test, S_IRUGO, pn544_test, NULL); + +static int __devinit pn544_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pn544_info *info; + struct pn544_nfc_platform_data *pdata; + int r = 0; + + dev_dbg(&client->dev, "%s\n", __func__); + dev_dbg(&client->dev, "IRQ: %d\n", client->irq); + + /* private data allocation */ + info = kzalloc(sizeof(struct pn544_info), GFP_KERNEL); + if (!info) { + dev_err(&client->dev, + "Cannot allocate memory for pn544_info.\n"); + r = -ENOMEM; + goto err_info_alloc; + } + + info->buflen = max(PN544_MSG_MAX_SIZE, PN544_MAX_I2C_TRANSFER); + info->buf = kzalloc(info->buflen, GFP_KERNEL); + if (!info->buf) { + dev_err(&client->dev, + "Cannot allocate memory for pn544_info->buf.\n"); + r = -ENOMEM; + goto err_buf_alloc; + } + + info->regs[0].supply = reg_vdd_io; + info->regs[1].supply = reg_vbat; + r = regulator_bulk_get(&client->dev, ARRAY_SIZE(info->regs), + info->regs); + if (r < 0) + goto err_kmalloc; + + info->i2c_dev = client; + info->state = PN544_ST_COLD; + info->read_irq = PN544_NONE; + mutex_init(&info->read_mutex); + mutex_init(&info->mutex); + init_waitqueue_head(&info->read_wait); + i2c_set_clientdata(client, info); + pdata = client->dev.platform_data; + if (!pdata) { + dev_err(&client->dev, "No platform data\n"); + r = -EINVAL; + goto err_reg; + } + + if (!pdata->request_resources) { + dev_err(&client->dev, "request_resources() missing\n"); + r = -EINVAL; + goto err_reg; + } + + r = pdata->request_resources(client); + if (r) { + dev_err(&client->dev, "Cannot get platform resources\n"); + goto err_reg; + } + + r = request_threaded_irq(client->irq, NULL, pn544_irq_thread_fn, + IRQF_TRIGGER_RISING, PN544_DRIVER_NAME, + info); + if (r < 0) { + dev_err(&client->dev, "Unable to register IRQ handler\n"); + goto err_res; + } + + /* If we don't have the test we don't need the sysfs file */ + if (pdata->test) { + r = device_create_file(&client->dev, &pn544_attr); + if (r) { + dev_err(&client->dev, + "sysfs registration failed, error %d\n", r); + goto err_irq; + } + } + + info->miscdev.minor = MISC_DYNAMIC_MINOR; + info->miscdev.name = PN544_DRIVER_NAME; + info->miscdev.fops = &pn544_fops; + info->miscdev.parent = &client->dev; + r = misc_register(&info->miscdev); + if (r < 0) { + dev_err(&client->dev, "Device registration failed\n"); + goto err_sysfs; + } + + dev_dbg(&client->dev, "%s: info: %p, pdata %p, client %p\n", + __func__, info, pdata, client); + + return 0; + +err_sysfs: + if (pdata->test) + device_remove_file(&client->dev, &pn544_attr); +err_irq: + free_irq(client->irq, info); +err_res: + if (pdata->free_resources) + pdata->free_resources(); +err_reg: + regulator_bulk_free(ARRAY_SIZE(info->regs), info->regs); +err_kmalloc: + kfree(info->buf); +err_buf_alloc: + kfree(info); +err_info_alloc: + return r; +} + +static __devexit int pn544_remove(struct i2c_client *client) +{ + struct pn544_info *info = i2c_get_clientdata(client); + struct pn544_nfc_platform_data *pdata = client->dev.platform_data; + + dev_dbg(&client->dev, "%s\n", __func__); + + misc_deregister(&info->miscdev); + if (pdata->test) + device_remove_file(&client->dev, &pn544_attr); + + if (info->state != PN544_ST_COLD) { + if (pdata->disable) + pdata->disable(); + + info->read_irq = PN544_NONE; + } + + free_irq(client->irq, info); + if (pdata->free_resources) + pdata->free_resources(); + + regulator_bulk_free(ARRAY_SIZE(info->regs), info->regs); + kfree(info->buf); + kfree(info); + + return 0; +} + +static struct i2c_driver pn544_driver = { + .driver = { + .name = PN544_DRIVER_NAME, +#ifdef CONFIG_PM + .pm = &pn544_pm_ops, +#endif + }, + .probe = pn544_probe, + .id_table = pn544_id_table, + .remove = __devexit_p(pn544_remove), +}; + +static int __init pn544_init(void) +{ + int r; + + pr_debug(DRIVER_DESC ": %s\n", __func__); + + r = i2c_add_driver(&pn544_driver); + if (r) { + pr_err(PN544_DRIVER_NAME ": driver registration failed\n"); + return r; + } + + return 0; +} + +static void __exit pn544_exit(void) +{ + i2c_del_driver(&pn544_driver); + pr_info(DRIVER_DESC ", Exiting.\n"); +} + +module_init(pn544_init); +module_exit(pn544_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION(DRIVER_DESC); diff --git a/include/linux/nfc/pn544.h b/include/linux/nfc/pn544.h new file mode 100644 index 0000000..7ab8521 --- /dev/null +++ b/include/linux/nfc/pn544.h @@ -0,0 +1,97 @@ +/* + * Driver include for the PN544 NFC chip. + * + * Copyright (C) Nokia Corporation + * + * Author: Jari Vanhala <ext-jari.vanhala@xxxxxxxxx> + * Contact: Matti Aaltoenn <matti.j.aaltonen@xxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef _PN544_H_ +#define _PN544_H_ + +#include <linux/i2c.h> + +#define PN544_DRIVER_NAME "pn544" +#define PN544_MAXWINDOW_SIZE 7 +#define PN544_WINDOW_SIZE 4 +#define PN544_RETRIES 10 +#define PN544_MAX_I2C_TRANSFER 0x0400 +#define PN544_MSG_MAX_SIZE 0x21 /* at normal HCI mode */ + +/* ioctl */ +#define PN544_CHAR_BASE 'P' +#define PN544_IOR(num, dtype) _IOR(PN544_CHAR_BASE, num, dtype) +#define PN544_IOW(num, dtype) _IOW(PN544_CHAR_BASE, num, dtype) +#define PN544_GET_FW_MODE PN544_IOW(1, unsigned int) +#define PN544_SET_FW_MODE PN544_IOW(2, unsigned int) +#define PN544_GET_DEBUG PN544_IOW(3, unsigned int) +#define PN544_SET_DEBUG PN544_IOW(4, unsigned int) + +/* Timing restrictions (ms) */ +#define PN544_RESETVEN_TIME 30 /* 7 */ +#define PN544_PVDDVEN_TIME 0 +#define PN544_VBATVEN_TIME 0 +#define PN544_GPIO4VEN_TIME 0 +#define PN544_WAKEUP_ACK 5 +#define PN544_WAKEUP_GUARD (PN544_WAKEUP_ACK + 1) +#define PN544_INACTIVITY_TIME 1000 +#define PN544_INTERFRAME_DELAY 200 /* us */ +#define PN544_BAUDRATE_CHANGE 150 /* us */ + +/* Debug bits */ +#define PN544_DEBUG_BUF 0x01 +#define PN544_DEBUG_READ 0x02 +#define PN544_DEBUG_WRITE 0x04 +#define PN544_DEBUG_IRQ 0x08 +#define PN544_DEBUG_CALLS 0x10 +#define PN544_DEBUG_MODE 0x20 + +/* Normal (HCI) mode */ +#define PN544_LLC_HCI_OVERHEAD 3 /* header + crc (to length) */ +#define PN544_LLC_MIN_SIZE (1 + PN544_LLC_HCI_OVERHEAD) /* length + */ +#define PN544_LLC_MAX_DATA (PN544_MSG_MAX_SIZE - 2) +#define PN544_LLC_MAX_HCI_SIZE (PN544_LLC_MAX_DATA - 2) + +struct pn544_llc_packet { + unsigned char length; /* of rest of packet */ + unsigned char header; + unsigned char data[PN544_LLC_MAX_DATA]; /* includes crc-ccitt */ +}; + +/* Firmware upgrade mode */ +#define PN544_FW_HEADER_SIZE 3 +/* max fw transfer is 1024bytes, but I2C limits it to 0xC0 */ +#define PN544_MAX_FW_DATA (PN544_MAX_I2C_TRANSFER - PN544_FW_HEADER_SIZE) + +struct pn544_fw_packet { + unsigned char command; /* status in answer */ + unsigned char length[2]; /* big-endian order (msf) */ + unsigned char data[PN544_MAX_FW_DATA]; +}; + +#ifdef __KERNEL__ +/* board config */ +struct pn544_nfc_platform_data { + int (*request_resources) (struct i2c_client *client); + void (*free_resources) (void); + void (*enable) (int fw); + int (*test) (void); + void (*disable) (void); +}; +#endif /* __KERNEL__ */ + +#endif /* _PN544_H_ */ -- 1.6.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
