diff options
author | Eric Lapuyade <eric.lapuyade@linux.intel.com> | 2012-10-02 18:44:06 +0200 |
---|---|---|
committer | Samuel Ortiz <sameo@linux.intel.com> | 2012-10-26 18:26:46 +0200 |
commit | 97f18414af395c547f20300e5d4c81d7190a4155 (patch) | |
tree | 4a2eb92f03d4bf8f8ff82452b2118f91d5780eef /drivers/nfc | |
parent | NFC: HCI check presence must not fail when driver doesn't support it (diff) | |
download | linux-97f18414af395c547f20300e5d4c81d7190a4155.tar.xz linux-97f18414af395c547f20300e5d4c81d7190a4155.zip |
NFC: Separate pn544 hci driver in HW dependant and independant parts
The driver now has all HCI stuff isolated in one file, and all the
hardware link specifics in another. Writing a pn544 driver on top of
another hardware link is now just a matter of adding a new file for that
new hardware specifics.
Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/nfc')
-rw-r--r-- | drivers/nfc/Makefile | 2 | ||||
-rw-r--r-- | drivers/nfc/pn544/Makefile | 7 | ||||
-rw-r--r-- | drivers/nfc/pn544/i2c.c | 500 | ||||
-rw-r--r-- | drivers/nfc/pn544/pn544.c (renamed from drivers/nfc/pn544_hci.c) | 438 | ||||
-rw-r--r-- | drivers/nfc/pn544/pn544.h | 32 |
5 files changed, 564 insertions, 415 deletions
diff --git a/drivers/nfc/Makefile b/drivers/nfc/Makefile index bf05831fdf09..36c359043f54 100644 --- a/drivers/nfc/Makefile +++ b/drivers/nfc/Makefile @@ -2,7 +2,7 @@ # Makefile for nfc devices # -obj-$(CONFIG_PN544_HCI_NFC) += pn544_hci.o +obj-$(CONFIG_PN544_HCI_NFC) += pn544/ obj-$(CONFIG_NFC_PN533) += pn533.o obj-$(CONFIG_NFC_WILINK) += nfcwilink.o diff --git a/drivers/nfc/pn544/Makefile b/drivers/nfc/pn544/Makefile new file mode 100644 index 000000000000..725733881eb3 --- /dev/null +++ b/drivers/nfc/pn544/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for PN544 HCI based NFC driver +# + +obj-$(CONFIG_PN544_HCI_NFC) += pn544_i2c.o + +pn544_i2c-y := pn544.o i2c.o diff --git a/drivers/nfc/pn544/i2c.c b/drivers/nfc/pn544/i2c.c new file mode 100644 index 000000000000..fb430d882352 --- /dev/null +++ b/drivers/nfc/pn544/i2c.c @@ -0,0 +1,500 @@ +/* + * I2C Link Layer for PN544 HCI based Driver + * + * Copyright (C) 2012 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions 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/crc-ccitt.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/gpio.h> +#include <linux/miscdevice.h> +#include <linux/interrupt.h> +#include <linux/delay.h> + +#include <linux/nfc/pn544.h> + +#include <net/nfc/hci.h> +#include <net/nfc/llc.h> + +#include "pn544.h" + +#define PN544_I2C_FRAME_HEADROOM 1 +#define PN544_I2C_FRAME_TAILROOM 2 + +/* framing in HCI mode */ +#define PN544_HCI_I2C_LLC_LEN 1 +#define PN544_HCI_I2C_LLC_CRC 2 +#define PN544_HCI_I2C_LLC_LEN_CRC (PN544_HCI_I2C_LLC_LEN + \ + PN544_HCI_I2C_LLC_CRC) +#define PN544_HCI_I2C_LLC_MIN_SIZE (1 + PN544_HCI_I2C_LLC_LEN_CRC) +#define PN544_HCI_I2C_LLC_MAX_PAYLOAD 29 +#define PN544_HCI_I2C_LLC_MAX_SIZE (PN544_HCI_I2C_LLC_LEN_CRC + 1 + \ + PN544_HCI_I2C_LLC_MAX_PAYLOAD) + +static struct i2c_device_id pn544_hci_i2c_id_table[] = { + {"pn544", 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, pn544_hci_i2c_id_table); + +#define PN544_HCI_I2C_DRIVER_NAME "pn544_hci_i2c" + +struct pn544_i2c_phy { + struct i2c_client *i2c_dev; + struct nfc_hci_dev *hdev; + + unsigned int gpio_en; + unsigned int gpio_irq; + unsigned int gpio_fw; + unsigned int en_polarity; + + int powered; + + int hard_fault; /* + * < 0 if hardware error occured (e.g. i2c err) + * and prevents normal operation. + */ +}; + +#define I2C_DUMP_SKB(info, skb) \ +do { \ + pr_debug("%s:\n", info); \ + print_hex_dump(KERN_DEBUG, "i2c: ", DUMP_PREFIX_OFFSET, \ + 16, 1, (skb)->data, (skb)->len, 0); \ +} while (0) + +static void pn544_hci_i2c_platform_init(struct pn544_i2c_phy *phy) +{ + int polarity, retry, ret; + char rset_cmd[] = { 0x05, 0xF9, 0x04, 0x00, 0xC3, 0xE5 }; + int count = sizeof(rset_cmd); + + pr_info(DRIVER_DESC ": %s\n", __func__); + dev_info(&phy->i2c_dev->dev, "Detecting nfc_en polarity\n"); + + /* Disable fw download */ + gpio_set_value(phy->gpio_fw, 0); + + for (polarity = 0; polarity < 2; polarity++) { + phy->en_polarity = polarity; + retry = 3; + while (retry--) { + /* power off */ + gpio_set_value(phy->gpio_en, !phy->en_polarity); + usleep_range(10000, 15000); + + /* power on */ + gpio_set_value(phy->gpio_en, phy->en_polarity); + usleep_range(10000, 15000); + + /* send reset */ + dev_dbg(&phy->i2c_dev->dev, "Sending reset cmd\n"); + ret = i2c_master_send(phy->i2c_dev, rset_cmd, count); + if (ret == count) { + dev_info(&phy->i2c_dev->dev, + "nfc_en polarity : active %s\n", + (polarity == 0 ? "low" : "high")); + goto out; + } + } + } + + dev_err(&phy->i2c_dev->dev, + "Could not detect nfc_en polarity, fallback to active high\n"); + +out: + gpio_set_value(phy->gpio_en, !phy->en_polarity); +} + +static int pn544_hci_i2c_enable(void *phy_id) +{ + struct pn544_i2c_phy *phy = phy_id; + + pr_info(DRIVER_DESC ": %s\n", __func__); + + gpio_set_value(phy->gpio_fw, 0); + gpio_set_value(phy->gpio_en, phy->en_polarity); + usleep_range(10000, 15000); + + phy->powered = 1; + + return 0; +} + +static void pn544_hci_i2c_disable(void *phy_id) +{ + struct pn544_i2c_phy *phy = phy_id; + + pr_info(DRIVER_DESC ": %s\n", __func__); + + gpio_set_value(phy->gpio_fw, 0); + gpio_set_value(phy->gpio_en, !phy->en_polarity); + usleep_range(10000, 15000); + + gpio_set_value(phy->gpio_en, phy->en_polarity); + usleep_range(10000, 15000); + + gpio_set_value(phy->gpio_en, !phy->en_polarity); + usleep_range(10000, 15000); + + phy->powered = 0; +} + +static void pn544_hci_i2c_add_len_crc(struct sk_buff *skb) +{ + u16 crc; + int len; + + len = skb->len + 2; + *skb_push(skb, 1) = len; + + crc = crc_ccitt(0xffff, skb->data, skb->len); + crc = ~crc; + *skb_put(skb, 1) = crc & 0xff; + *skb_put(skb, 1) = crc >> 8; +} + +static void pn544_hci_i2c_remove_len_crc(struct sk_buff *skb) +{ + skb_pull(skb, PN544_I2C_FRAME_HEADROOM); + skb_trim(skb, PN544_I2C_FRAME_TAILROOM); +} + +/* + * Writing a frame must not return the number of written bytes. + * It must return either zero for success, or <0 for error. + * In addition, it must not alter the skb + */ +static int pn544_hci_i2c_write(void *phy_id, struct sk_buff *skb) +{ + int r; + struct pn544_i2c_phy *phy = phy_id; + struct i2c_client *client = phy->i2c_dev; + + if (phy->hard_fault != 0) + return phy->hard_fault; + + usleep_range(3000, 6000); + + pn544_hci_i2c_add_len_crc(skb); + + I2C_DUMP_SKB("i2c frame written", skb); + + r = i2c_master_send(client, skb->data, skb->len); + + if (r == -EREMOTEIO) { /* Retry, chip was in standby */ + usleep_range(6000, 10000); + r = i2c_master_send(client, skb->data, skb->len); + } + + if (r >= 0) { + if (r != skb->len) + r = -EREMOTEIO; + else + r = 0; + } + + pn544_hci_i2c_remove_len_crc(skb); + + return r; +} + +static int check_crc(u8 *buf, int buflen) +{ + int len; + u16 crc; + + len = buf[0] + 1; + crc = crc_ccitt(0xffff, buf, len - 2); + crc = ~crc; + + if (buf[len - 2] != (crc & 0xff) || buf[len - 1] != (crc >> 8)) { + pr_err(PN544_HCI_I2C_DRIVER_NAME + ": CRC error 0x%x != 0x%x 0x%x\n", + crc, buf[len - 1], buf[len - 2]); + + pr_info(DRIVER_DESC ": %s : BAD CRC\n", __func__); + print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, + 16, 2, buf, buflen, false); + return -EPERM; + } + return 0; +} + +/* + * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees + * that i2c bus will be flushed and that next read will start on a new frame. + * returned skb contains only LLC header and payload. + * returns: + * -EREMOTEIO : i2c read error (fatal) + * -EBADMSG : frame was incorrect and discarded + * -ENOMEM : cannot allocate skb, frame dropped + */ +static int pn544_hci_i2c_read(struct pn544_i2c_phy *phy, struct sk_buff **skb) +{ + int r; + u8 len; + u8 tmp[PN544_HCI_I2C_LLC_MAX_SIZE - 1]; + struct i2c_client *client = phy->i2c_dev; + + r = i2c_master_recv(client, &len, 1); + if (r != 1) { + dev_err(&client->dev, "cannot read len byte\n"); + return -EREMOTEIO; + } + + if ((len < (PN544_HCI_I2C_LLC_MIN_SIZE - 1)) || + (len > (PN544_HCI_I2C_LLC_MAX_SIZE - 1))) { + dev_err(&client->dev, "invalid len byte\n"); + r = -EBADMSG; + goto flush; + } + + *skb = alloc_skb(1 + len, GFP_KERNEL); + if (*skb == NULL) { + r = -ENOMEM; + goto flush; + } + + *skb_put(*skb, 1) = len; + + r = i2c_master_recv(client, skb_put(*skb, len), len); + if (r != len) { + kfree_skb(*skb); + return -EREMOTEIO; + } + + I2C_DUMP_SKB("i2c frame read", *skb); + + r = check_crc((*skb)->data, (*skb)->len); + if (r != 0) { + kfree_skb(*skb); + r = -EBADMSG; + goto flush; + } + + skb_pull(*skb, 1); + skb_trim(*skb, (*skb)->len - 2); + + usleep_range(3000, 6000); + + return 0; + +flush: + if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0) + r = -EREMOTEIO; + + usleep_range(3000, 6000); + + return r; +} + +/* + * Reads an shdlc frame from the chip. This is not as straightforward as it + * seems. There are cases where we could loose the frame start synchronization. + * The frame format is len-data-crc, and corruption can occur anywhere while + * transiting on i2c bus, such that we could read an invalid len. + * In order to recover synchronization with the next frame, we must be sure + * to read the real amount of data without using the len byte. We do this by + * assuming the following: + * - the chip will always present only one single complete frame on the bus + * before triggering the interrupt + * - the chip will not present a new frame until we have completely read + * the previous one (or until we have handled the interrupt). + * The tricky case is when we read a corrupted len that is less than the real + * len. We must detect this here in order to determine that we need to flush + * the bus. This is the reason why we check the crc here. + */ +static irqreturn_t pn544_hci_i2c_irq_thread_fn(int irq, void *phy_id) +{ + struct pn544_i2c_phy *phy = phy_id; + struct i2c_client *client; + struct sk_buff *skb = NULL; + int r; + + if (!phy || irq != phy->i2c_dev->irq) { + WARN_ON_ONCE(1); + return IRQ_NONE; + } + + client = phy->i2c_dev; + dev_dbg(&client->dev, "IRQ\n"); + + if (phy->hard_fault != 0) + return IRQ_HANDLED; + + r = pn544_hci_i2c_read(phy, &skb); + if (r == -EREMOTEIO) { + phy->hard_fault = r; + + nfc_hci_recv_frame(phy->hdev, NULL); + + return IRQ_HANDLED; + } else if ((r == -ENOMEM) || (r == -EBADMSG)) { + return IRQ_HANDLED; + } + + nfc_hci_recv_frame(phy->hdev, skb); + + return IRQ_HANDLED; +} + +static struct nfc_phy_ops i2c_phy_ops = { + .write = pn544_hci_i2c_write, + .enable = pn544_hci_i2c_enable, + .disable = pn544_hci_i2c_disable, +}; + +static int __devinit pn544_hci_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pn544_i2c_phy *phy; + 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); + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "Need I2C_FUNC_I2C\n"); + return -ENODEV; + } + + phy = kzalloc(sizeof(struct pn544_i2c_phy), GFP_KERNEL); + if (!phy) { + dev_err(&client->dev, + "Cannot allocate memory for pn544 i2c phy.\n"); + r = -ENOMEM; + goto err_phy_alloc; + } + + phy->i2c_dev = client; + i2c_set_clientdata(client, phy); + + pdata = client->dev.platform_data; + if (pdata == NULL) { + dev_err(&client->dev, "No platform data\n"); + r = -EINVAL; + goto err_pdata; + } + + if (pdata->request_resources == NULL) { + dev_err(&client->dev, "request_resources() missing\n"); + r = -EINVAL; + goto err_pdata; + } + + r = pdata->request_resources(client); + if (r) { + dev_err(&client->dev, "Cannot get platform resources\n"); + goto err_pdata; + } + + phy->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE); + phy->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET); + phy->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ); + + pn544_hci_i2c_platform_init(phy); + + r = request_threaded_irq(client->irq, NULL, pn544_hci_i2c_irq_thread_fn, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + PN544_HCI_I2C_DRIVER_NAME, phy); + if (r < 0) { + dev_err(&client->dev, "Unable to register IRQ handler\n"); + goto err_rti; + } + + r = pn544_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME, + PN544_I2C_FRAME_HEADROOM, PN544_I2C_FRAME_TAILROOM, + PN544_HCI_I2C_LLC_MAX_PAYLOAD, &phy->hdev); + if (r < 0) + goto err_hci; + + return 0; + +err_hci: + free_irq(client->irq, phy); + +err_rti: + if (pdata->free_resources != NULL) + pdata->free_resources(); + +err_pdata: + kfree(phy); + +err_phy_alloc: + return r; +} + +static __devexit int pn544_hci_i2c_remove(struct i2c_client *client) +{ + struct pn544_i2c_phy *phy = i2c_get_clientdata(client); + struct pn544_nfc_platform_data *pdata = client->dev.platform_data; + + dev_dbg(&client->dev, "%s\n", __func__); + + pn544_hci_remove(phy->hdev); + + if (phy->powered) + pn544_hci_i2c_disable(phy); + + free_irq(client->irq, phy); + if (pdata->free_resources) + pdata->free_resources(); + + kfree(phy); + + return 0; +} + +static struct i2c_driver pn544_hci_i2c_driver = { + .driver = { + .name = PN544_HCI_I2C_DRIVER_NAME, + }, + .probe = pn544_hci_i2c_probe, + .id_table = pn544_hci_i2c_id_table, + .remove = __devexit_p(pn544_hci_i2c_remove), +}; + +static int __init pn544_hci_i2c_init(void) +{ + int r; + + pr_debug(DRIVER_DESC ": %s\n", __func__); + + r = i2c_add_driver(&pn544_hci_i2c_driver); + if (r) { + pr_err(PN544_HCI_I2C_DRIVER_NAME + ": driver registration failed\n"); + return r; + } + + return 0; +} + +static void __exit pn544_hci_i2c_exit(void) +{ + i2c_del_driver(&pn544_hci_i2c_driver); +} + +module_init(pn544_hci_i2c_init); +module_exit(pn544_hci_i2c_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION(DRIVER_DESC); diff --git a/drivers/nfc/pn544_hci.c b/drivers/nfc/pn544/pn544.c index 70858b5f81e4..cf344450815c 100644 --- a/drivers/nfc/pn544_hci.c +++ b/drivers/nfc/pn544/pn544.c @@ -18,47 +18,21 @@ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#include <linux/crc-ccitt.h> -#include <linux/module.h> #include <linux/delay.h> #include <linux/slab.h> -#include <linux/miscdevice.h> -#include <linux/interrupt.h> -#include <linux/gpio.h> -#include <linux/i2c.h> #include <linux/nfc.h> #include <net/nfc/hci.h> #include <net/nfc/llc.h> -#include <linux/nfc/pn544.h> - -#define DRIVER_DESC "HCI NFC driver for PN544" - -#define PN544_HCI_DRIVER_NAME "pn544_hci" +#include "pn544.h" /* Timing restrictions (ms) */ #define PN544_HCI_RESETVEN_TIME 30 -static struct i2c_device_id pn544_hci_id_table[] = { - {"pn544", 0}, - {} -}; - -MODULE_DEVICE_TABLE(i2c, pn544_hci_id_table); - #define HCI_MODE 0 #define FW_MODE 1 -/* framing in HCI mode */ -#define PN544_HCI_LLC_LEN 1 -#define PN544_HCI_LLC_CRC 2 -#define PN544_HCI_LLC_LEN_CRC (PN544_HCI_LLC_LEN + PN544_HCI_LLC_CRC) -#define PN544_HCI_LLC_MIN_SIZE (1 + PN544_HCI_LLC_LEN_CRC) -#define PN544_HCI_LLC_MAX_PAYLOAD 29 -#define PN544_HCI_LLC_MAX_SIZE (PN544_HCI_LLC_LEN_CRC + 1 + \ - PN544_HCI_LLC_MAX_PAYLOAD) - enum pn544_state { PN544_ST_COLD, PN544_ST_FW_READY, @@ -141,259 +115,22 @@ static struct nfc_hci_gate pn544_gates[] = { /* Largest headroom needed for outgoing custom commands */ #define PN544_CMDS_HEADROOM 2 -#define PN544_FRAME_HEADROOM 1 -#define PN544_FRAME_TAILROOM 2 struct pn544_hci_info { - struct i2c_client *i2c_dev; + struct nfc_phy_ops *phy_ops; + void *phy_id; + struct nfc_hci_dev *hdev; enum pn544_state state; struct mutex info_lock; - unsigned int gpio_en; - unsigned int gpio_irq; - unsigned int gpio_fw; - unsigned int en_polarity; - - int hard_fault; /* - * < 0 if hardware error occured (e.g. i2c err) - * and prevents normal operation. - */ int async_cb_type; data_exchange_cb_t async_cb; void *async_cb_context; }; -static void pn544_hci_platform_init(struct pn544_hci_info *info) -{ - int polarity, retry, ret; - char rset_cmd[] = { 0x05, 0xF9, 0x04, 0x00, 0xC3, 0xE5 }; - int count = sizeof(rset_cmd); - - pr_info(DRIVER_DESC ": %s\n", __func__); - dev_info(&info->i2c_dev->dev, "Detecting nfc_en polarity\n"); - - /* Disable fw download */ - gpio_set_value(info->gpio_fw, 0); - - for (polarity = 0; polarity < 2; polarity++) { - info->en_polarity = polarity; - retry = 3; - while (retry--) { - /* power off */ - gpio_set_value(info->gpio_en, !info->en_polarity); - usleep_range(10000, 15000); - - /* power on */ - gpio_set_value(info->gpio_en, info->en_polarity); - usleep_range(10000, 15000); - - /* send reset */ - dev_dbg(&info->i2c_dev->dev, "Sending reset cmd\n"); - ret = i2c_master_send(info->i2c_dev, rset_cmd, count); - if (ret == count) { - dev_info(&info->i2c_dev->dev, - "nfc_en polarity : active %s\n", - (polarity == 0 ? "low" : "high")); - goto out; - } - } - } - - dev_err(&info->i2c_dev->dev, - "Could not detect nfc_en polarity, fallback to active high\n"); - -out: - gpio_set_value(info->gpio_en, !info->en_polarity); -} - -static int pn544_hci_enable(struct pn544_hci_info *info, int mode) -{ - pr_info(DRIVER_DESC ": %s\n", __func__); - - gpio_set_value(info->gpio_fw, 0); - gpio_set_value(info->gpio_en, info->en_polarity); - usleep_range(10000, 15000); - - return 0; -} - -static void pn544_hci_disable(struct pn544_hci_info *info) -{ - pr_info(DRIVER_DESC ": %s\n", __func__); - - gpio_set_value(info->gpio_fw, 0); - gpio_set_value(info->gpio_en, !info->en_polarity); - usleep_range(10000, 15000); - - gpio_set_value(info->gpio_en, info->en_polarity); - usleep_range(10000, 15000); - - gpio_set_value(info->gpio_en, !info->en_polarity); - usleep_range(10000, 15000); -} - -static int pn544_hci_i2c_write(struct i2c_client *client, u8 *buf, int len) -{ - int r; - - usleep_range(3000, 6000); - - r = i2c_master_send(client, buf, len); - - if (r == -EREMOTEIO) { /* Retry, chip was in standby */ - usleep_range(6000, 10000); - r = i2c_master_send(client, buf, len); - } - - if (r >= 0) { - if (r != len) - return -EREMOTEIO; - else - return 0; - } - - return r; -} - -static int check_crc(u8 *buf, int buflen) -{ - int len; - u16 crc; - - len = buf[0] + 1; - crc = crc_ccitt(0xffff, buf, len - 2); - crc = ~crc; - - if (buf[len - 2] != (crc & 0xff) || buf[len - 1] != (crc >> 8)) { - pr_err(PN544_HCI_DRIVER_NAME ": CRC error 0x%x != 0x%x 0x%x\n", - crc, buf[len - 1], buf[len - 2]); - - pr_info(DRIVER_DESC ": %s : BAD CRC\n", __func__); - print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, - 16, 2, buf, buflen, false); - return -EPERM; - } - return 0; -} - -/* - * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees - * that i2c bus will be flushed and that next read will start on a new frame. - * returned skb contains only LLC header and payload. - * returns: - * -EREMOTEIO : i2c read error (fatal) - * -EBADMSG : frame was incorrect and discarded - * -ENOMEM : cannot allocate skb, frame dropped - */ -static int pn544_hci_i2c_read(struct i2c_client *client, struct sk_buff **skb) -{ - int r; - u8 len; - u8 tmp[PN544_HCI_LLC_MAX_SIZE - 1]; - - r = i2c_master_recv(client, &len, 1); - if (r != 1) { - dev_err(&client->dev, "cannot read len byte\n"); - return -EREMOTEIO; - } - - if ((len < (PN544_HCI_LLC_MIN_SIZE - 1)) || - (len > (PN544_HCI_LLC_MAX_SIZE - 1))) { - dev_err(&client->dev, "invalid len byte\n"); - r = -EBADMSG; - goto flush; - } - - *skb = alloc_skb(1 + len, GFP_KERNEL); - if (*skb == NULL) { - r = -ENOMEM; - goto flush; - } - - *skb_put(*skb, 1) = len; - - r = i2c_master_recv(client, skb_put(*skb, len), len); - if (r != len) { - kfree_skb(*skb); - return -EREMOTEIO; - } - - r = check_crc((*skb)->data, (*skb)->len); - if (r != 0) { - kfree_skb(*skb); - r = -EBADMSG; - goto flush; - } - - skb_pull(*skb, 1); - skb_trim(*skb, (*skb)->len - 2); - - usleep_range(3000, 6000); - - return 0; - -flush: - if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0) - r = -EREMOTEIO; - - usleep_range(3000, 6000); - - return r; -} - -/* - * Reads an shdlc frame from the chip. This is not as straightforward as it - * seems. There are cases where we could loose the frame start synchronization. - * The frame format is len-data-crc, and corruption can occur anywhere while - * transiting on i2c bus, such that we could read an invalid len. - * In order to recover synchronization with the next frame, we must be sure - * to read the real amount of data without using the len byte. We do this by - * assuming the following: - * - the chip will always present only one single complete frame on the bus - * before triggering the interrupt - * - the chip will not present a new frame until we have completely read - * the previous one (or until we have handled the interrupt). - * The tricky case is when we read a corrupted len that is less than the real - * len. We must detect this here in order to determine that we need to flush - * the bus. This is the reason why we check the crc here. - */ -static irqreturn_t pn544_hci_irq_thread_fn(int irq, void *dev_id) -{ - struct pn544_hci_info *info = dev_id; - struct i2c_client *client; - struct sk_buff *skb = NULL; - int r; - - if (!info || irq != info->i2c_dev->irq) { - WARN_ON_ONCE(1); - return IRQ_NONE; - } - - client = info->i2c_dev; - dev_dbg(&client->dev, "IRQ\n"); - - if (info->hard_fault != 0) - return IRQ_HANDLED; - - r = pn544_hci_i2c_read(client, &skb); - if (r == -EREMOTEIO) { - info->hard_fault = r; - - nfc_hci_recv_frame(info->hdev, NULL); - - return IRQ_HANDLED; - } else if ((r == -ENOMEM) || (r == -EBADMSG)) { - return IRQ_HANDLED; - } - - nfc_hci_recv_frame(info->hdev, skb); - - return IRQ_HANDLED; -} - static int pn544_hci_open(struct nfc_hci_dev *hdev) { struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev); @@ -406,7 +143,7 @@ static int pn544_hci_open(struct nfc_hci_dev *hdev) goto out; } - r = pn544_hci_enable(info, HCI_MODE); + r = info->phy_ops->enable(info->phy_id); if (r == 0) info->state = PN544_ST_READY; @@ -425,7 +162,7 @@ static void pn544_hci_close(struct nfc_hci_dev *hdev) if (info->state == PN544_ST_COLD) goto out; - pn544_hci_disable(info); + info->phy_ops->disable(info->phy_id); info->state = PN544_ST_COLD; @@ -600,40 +337,11 @@ static int pn544_hci_ready(struct nfc_hci_dev *hdev) return 0; } -static void pn544_hci_add_len_crc(struct sk_buff *skb) -{ - u16 crc; - int len; - - len = skb->len + 2; - *skb_push(skb, 1) = len; - - crc = crc_ccitt(0xffff, skb->data, skb->len); - crc = ~crc; - *skb_put(skb, 1) = crc & 0xff; - *skb_put(skb, 1) = crc >> 8; -} - -static void pn544_hci_remove_len_crc(struct sk_buff *skb) -{ - skb_pull(skb, PN544_FRAME_HEADROOM); - skb_trim(skb, PN544_FRAME_TAILROOM); -} - static int pn544_hci_xmit(struct nfc_hci_dev *hdev, struct sk_buff *skb) { struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev); - struct i2c_client *client = info->i2c_dev; - int r; - - if (info->hard_fault != 0) - return info->hard_fault; - - pn544_hci_add_len_crc(skb); - r = pn544_hci_i2c_write(client, skb->data, skb->len); - pn544_hci_remove_len_crc(skb); - return r; + return info->phy_ops->write(info->phy_id, skb); } static int pn544_hci_start_poll(struct nfc_hci_dev *hdev, @@ -1076,68 +784,26 @@ static struct nfc_hci_ops pn544_hci_ops = { .event_received = pn544_hci_event_received, }; -static int __devinit pn544_hci_probe(struct i2c_client *client, - const struct i2c_device_id *id) +int pn544_hci_probe(void *phy_id, struct nfc_phy_ops *phy_ops, char *llc_name, + int phy_headroom, int phy_tailroom, int phy_payload, + struct nfc_hci_dev **hdev) { struct pn544_hci_info *info; - struct pn544_nfc_platform_data *pdata; - int r = 0; u32 protocols; struct nfc_hci_init_data init_data; - - dev_dbg(&client->dev, "%s\n", __func__); - dev_dbg(&client->dev, "IRQ: %d\n", client->irq); - - if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { - dev_err(&client->dev, "Need I2C_FUNC_I2C\n"); - return -ENODEV; - } + int r; info = kzalloc(sizeof(struct pn544_hci_info), GFP_KERNEL); if (!info) { - dev_err(&client->dev, - "Cannot allocate memory for pn544_hci_info.\n"); + pr_err("Cannot allocate memory for pn544_hci_info.\n"); r = -ENOMEM; goto err_info_alloc; } - info->i2c_dev = client; + info->phy_ops = phy_ops; + info->phy_id = phy_id; info->state = PN544_ST_COLD; mutex_init(&info->info_lock); - i2c_set_clientdata(client, info); - - pdata = client->dev.platform_data; - if (pdata == NULL) { - dev_err(&client->dev, "No platform data\n"); - r = -EINVAL; - goto err_pdata; - } - - if (pdata->request_resources == NULL) { - dev_err(&client->dev, "request_resources() missing\n"); - r = -EINVAL; - goto err_pdata; - } - - r = pdata->request_resources(client); - if (r) { - dev_err(&client->dev, "Cannot get platform resources\n"); - goto err_pdata; - } - - info->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE); - info->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET); - info->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ); - - pn544_hci_platform_init(info); - - r = request_threaded_irq(client->irq, NULL, pn544_hci_irq_thread_fn, - IRQF_TRIGGER_RISING | IRQF_ONESHOT, - PN544_HCI_DRIVER_NAME, info); - if (r < 0) { - dev_err(&client->dev, "Unable to register IRQ handler\n"); - goto err_rti; - } init_data.gate_count = ARRAY_SIZE(pn544_gates); @@ -1157,13 +823,11 @@ static int __devinit pn544_hci_probe(struct i2c_client *client, NFC_PROTO_NFC_DEP_MASK; info->hdev = nfc_hci_allocate_device(&pn544_hci_ops, &init_data, - protocols, LLC_SHDLC_NAME, - PN544_FRAME_HEADROOM + - PN544_CMDS_HEADROOM, - PN544_FRAME_TAILROOM, - PN544_HCI_LLC_MAX_PAYLOAD); + protocols, llc_name, + phy_headroom + PN544_CMDS_HEADROOM, + phy_tailroom, phy_payload); if (!info->hdev) { - dev_err(&client->dev, "Cannot allocate nfc hdev.\n"); + pr_err("Cannot allocate nfc hdev.\n"); r = -ENOMEM; goto err_alloc_hdev; } @@ -1174,79 +838,25 @@ static int __devinit pn544_hci_probe(struct i2c_client *client, if (r) goto err_regdev; + *hdev = info->hdev; + return 0; err_regdev: nfc_hci_free_device(info->hdev); err_alloc_hdev: - free_irq(client->irq, info); - -err_rti: - if (pdata->free_resources != NULL) - pdata->free_resources(); - -err_pdata: kfree(info); err_info_alloc: return r; } -static __devexit int pn544_hci_remove(struct i2c_client *client) +void pn544_hci_remove(struct nfc_hci_dev *hdev) { - struct pn544_hci_info *info = i2c_get_clientdata(client); - struct pn544_nfc_platform_data *pdata = client->dev.platform_data; - - dev_dbg(&client->dev, "%s\n", __func__); - - nfc_hci_free_device(info->hdev); - - if (info->state != PN544_ST_COLD) { - if (pdata->disable) - pdata->disable(); - } - - free_irq(client->irq, info); - if (pdata->free_resources) - pdata->free_resources(); + struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev); + nfc_hci_unregister_device(hdev); + nfc_hci_free_device(hdev); kfree(info); - - return 0; -} - -static struct i2c_driver pn544_hci_driver = { - .driver = { - .name = PN544_HCI_DRIVER_NAME, - }, - .probe = pn544_hci_probe, - .id_table = pn544_hci_id_table, - .remove = __devexit_p(pn544_hci_remove), -}; - -static int __init pn544_hci_init(void) -{ - int r; - - pr_debug(DRIVER_DESC ": %s\n", __func__); - - r = i2c_add_driver(&pn544_hci_driver); - if (r) { - pr_err(PN544_HCI_DRIVER_NAME ": driver registration failed\n"); - return r; - } - - return 0; } - -static void __exit pn544_hci_exit(void) -{ - i2c_del_driver(&pn544_hci_driver); -} - -module_init(pn544_hci_init); -module_exit(pn544_hci_exit); - -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION(DRIVER_DESC); diff --git a/drivers/nfc/pn544/pn544.h b/drivers/nfc/pn544/pn544.h new file mode 100644 index 000000000000..f47c6454914b --- /dev/null +++ b/drivers/nfc/pn544/pn544.h @@ -0,0 +1,32 @@ +/* + * Copyright (C) 2011 - 2012 Intel Corporation. All rights reserved. + * + * 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. + * + * 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 __LOCAL_PN544_H_ +#define __LOCAL_PN544_H_ + +#include <net/nfc/hci.h> + +#define DRIVER_DESC "HCI NFC driver for PN544" + +int pn544_hci_probe(void *phy_id, struct nfc_phy_ops *phy_ops, char *llc_name, + int phy_headroom, int phy_tailroom, int phy_payload, + struct nfc_hci_dev **hdev); +void pn544_hci_remove(struct nfc_hci_dev *hdev); + +#endif /* __LOCAL_PN544_H_ */ |