diff options
author | Clément Perrochaud <clement.perrochaud@nxp.com> | 2015-03-09 11:12:05 +0100 |
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committer | Samuel Ortiz <sameo@linux.intel.com> | 2015-03-26 11:21:41 +0100 |
commit | 6be88670fc59d50426f90f734a36b90e1de7d148 (patch) | |
tree | 8296eaff5b2747937b4239fcee58f5fa380926dc /drivers/nfc | |
parent | dece45855a8b0d1dcf48eb01d0822070ded6a4c8 (diff) | |
download | op-kernel-dev-6be88670fc59d50426f90f734a36b90e1de7d148.zip op-kernel-dev-6be88670fc59d50426f90f734a36b90e1de7d148.tar.gz |
NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver
Add a module to the NXP-NCI driver to support NFC controllers with an
I2C control interface, such as the NPC100.
Signed-off-by: Clément Perrochaud <clement.perrochaud@effinnov.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/nfc')
-rw-r--r-- | drivers/nfc/nxp-nci/Kconfig | 12 | ||||
-rw-r--r-- | drivers/nfc/nxp-nci/Makefile | 2 | ||||
-rw-r--r-- | drivers/nfc/nxp-nci/i2c.c | 415 |
3 files changed, 429 insertions, 0 deletions
diff --git a/drivers/nfc/nxp-nci/Kconfig b/drivers/nfc/nxp-nci/Kconfig index 5f60c7c..37b4061 100644 --- a/drivers/nfc/nxp-nci/Kconfig +++ b/drivers/nfc/nxp-nci/Kconfig @@ -11,3 +11,15 @@ config NFC_NXP_NCI To compile this driver as a module, choose m here. The module will be called nxp_nci. Say N if unsure. + +config NFC_NXP_NCI_I2C + tristate "NXP-NCI I2C support" + depends on NFC_NXP_NCI && I2C + ---help--- + This module adds support for an I2C interface to the NXP NCI + chips. + Select this if your platform is using the I2C bus. + + To compile this driver as a module, choose m here. The module will + be called nxp_nci_i2c. + Say Y if unsure. diff --git a/drivers/nfc/nxp-nci/Makefile b/drivers/nfc/nxp-nci/Makefile index 8f1e328..c008be3 100644 --- a/drivers/nfc/nxp-nci/Makefile +++ b/drivers/nfc/nxp-nci/Makefile @@ -3,7 +3,9 @@ # nxp-nci-objs = core.o firmware.o +nxp-nci_i2c-objs = i2c.o obj-$(CONFIG_NFC_NXP_NCI) += nxp-nci.o +obj-$(CONFIG_NFC_NXP_NCI_I2C) += nxp-nci_i2c.o ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c new file mode 100644 index 0000000..17bd67d --- /dev/null +++ b/drivers/nfc/nxp-nci/i2c.c @@ -0,0 +1,415 @@ +/* + * I2C link layer for the NXP NCI driver + * + * Copyright (C) 2014 NXP Semiconductors All rights reserved. + * + * Authors: Clément Perrochaud <clement.perrochaud@nxp.com> + * + * Derived from PN544 device 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, see <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/nfc.h> +#include <linux/of_gpio.h> +#include <linux/of_irq.h> +#include <linux/platform_data/nxp-nci.h> +#include <linux/unaligned/access_ok.h> + +#include <net/nfc/nfc.h> + +#include "nxp-nci.h" + +#define NXP_NCI_I2C_DRIVER_NAME "nxp-nci_i2c" + +#define NXP_NCI_I2C_MAX_PAYLOAD 32 + +struct nxp_nci_i2c_phy { + struct i2c_client *i2c_dev; + struct nci_dev *ndev; + + unsigned int gpio_en; + unsigned int gpio_fw; + + int hard_fault; /* + * < 0 if hardware error occurred (e.g. i2c err) + * and prevents normal operation. + */ +}; + +static int nxp_nci_i2c_set_mode(void *phy_id, + enum nxp_nci_mode mode) +{ + struct nxp_nci_i2c_phy *phy = (struct nxp_nci_i2c_phy *) phy_id; + + gpio_set_value(phy->gpio_fw, (mode == NXP_NCI_MODE_FW) ? 1 : 0); + gpio_set_value(phy->gpio_en, (mode != NXP_NCI_MODE_COLD) ? 1 : 0); + usleep_range(10000, 15000); + + if (mode == NXP_NCI_MODE_COLD) + phy->hard_fault = 0; + + return 0; +} + +static int nxp_nci_i2c_write(void *phy_id, struct sk_buff *skb) +{ + int r; + struct nxp_nci_i2c_phy *phy = phy_id; + struct i2c_client *client = phy->i2c_dev; + + if (phy->hard_fault != 0) + return phy->hard_fault; + + r = i2c_master_send(client, skb->data, skb->len); + if (r == -EREMOTEIO) { + /* Retry, chip was in standby */ + usleep_range(110000, 120000); + r = i2c_master_send(client, skb->data, skb->len); + } + + if (r < 0) { + nfc_err(&client->dev, "Error %d on I2C send\n", r); + } else if (r != skb->len) { + nfc_err(&client->dev, + "Invalid length sent: %u (expected %u)\n", + r, skb->len); + r = -EREMOTEIO; + } else { + /* Success but return 0 and not number of bytes */ + r = 0; + } + + return r; +} + +static struct nxp_nci_phy_ops i2c_phy_ops = { + .set_mode = nxp_nci_i2c_set_mode, + .write = nxp_nci_i2c_write, +}; + +static int nxp_nci_i2c_fw_read(struct nxp_nci_i2c_phy *phy, + struct sk_buff **skb) +{ + struct i2c_client *client = phy->i2c_dev; + u16 header; + size_t frame_len; + int r; + + r = i2c_master_recv(client, (u8 *) &header, NXP_NCI_FW_HDR_LEN); + if (r < 0) { + goto fw_read_exit; + } else if (r != NXP_NCI_FW_HDR_LEN) { + nfc_err(&client->dev, "Incorrect header length: %u\n", r); + r = -EBADMSG; + goto fw_read_exit; + } + + frame_len = (get_unaligned_be16(&header) & NXP_NCI_FW_FRAME_LEN_MASK) + + NXP_NCI_FW_CRC_LEN; + + *skb = alloc_skb(NXP_NCI_FW_HDR_LEN + frame_len, GFP_KERNEL); + if (*skb == NULL) { + r = -ENOMEM; + goto fw_read_exit; + } + + memcpy(skb_put(*skb, NXP_NCI_FW_HDR_LEN), &header, NXP_NCI_FW_HDR_LEN); + + r = i2c_master_recv(client, skb_put(*skb, frame_len), frame_len); + if (r != frame_len) { + nfc_err(&client->dev, + "Invalid frame length: %u (expected %zu)\n", + r, frame_len); + r = -EBADMSG; + goto fw_read_exit_free_skb; + } + + return 0; + +fw_read_exit_free_skb: + kfree_skb(*skb); +fw_read_exit: + return r; +} + +static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy, + struct sk_buff **skb) +{ + struct nci_ctrl_hdr header; /* May actually be a data header */ + struct i2c_client *client = phy->i2c_dev; + int r; + + r = i2c_master_recv(client, (u8 *) &header, NCI_CTRL_HDR_SIZE); + if (r < 0) { + goto nci_read_exit; + } else if (r != NCI_CTRL_HDR_SIZE) { + nfc_err(&client->dev, "Incorrect header length: %u\n", r); + r = -EBADMSG; + goto nci_read_exit; + } + + *skb = alloc_skb(NCI_CTRL_HDR_SIZE + header.plen, GFP_KERNEL); + if (*skb == NULL) { + r = -ENOMEM; + goto nci_read_exit; + } + + memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header, + NCI_CTRL_HDR_SIZE); + + r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen); + if (r != header.plen) { + nfc_err(&client->dev, + "Invalid frame payload length: %u (expected %u)\n", + r, header.plen); + r = -EBADMSG; + goto nci_read_exit_free_skb; + } + + return 0; + +nci_read_exit_free_skb: + kfree_skb(*skb); +nci_read_exit: + return r; +} + +static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id) +{ + struct nxp_nci_i2c_phy *phy = phy_id; + struct i2c_client *client; + struct nxp_nci_info *info; + + struct sk_buff *skb = NULL; + int r = 0; + + if (!phy || !phy->ndev) + goto exit_irq_none; + + client = phy->i2c_dev; + + if (!client || irq != client->irq) + goto exit_irq_none; + + info = nci_get_drvdata(phy->ndev); + + if (!info) + goto exit_irq_none; + + mutex_lock(&info->info_lock); + + if (phy->hard_fault != 0) + goto exit_irq_handled; + + switch (info->mode) { + case NXP_NCI_MODE_NCI: + r = nxp_nci_i2c_nci_read(phy, &skb); + break; + case NXP_NCI_MODE_FW: + r = nxp_nci_i2c_fw_read(phy, &skb); + break; + case NXP_NCI_MODE_COLD: + r = -EREMOTEIO; + break; + } + + if (r == -EREMOTEIO) { + phy->hard_fault = r; + skb = NULL; + } else if (r < 0) { + nfc_err(&client->dev, "Read failed with error %d\n", r); + goto exit_irq_handled; + } + + switch (info->mode) { + case NXP_NCI_MODE_NCI: + nci_recv_frame(phy->ndev, skb); + break; + case NXP_NCI_MODE_FW: + nxp_nci_fw_recv_frame(phy->ndev, skb); + break; + case NXP_NCI_MODE_COLD: + break; + } + +exit_irq_handled: + mutex_unlock(&info->info_lock); + return IRQ_HANDLED; +exit_irq_none: + WARN_ON_ONCE(1); + return IRQ_NONE; +} + +#ifdef CONFIG_OF + +static int nxp_nci_i2c_parse_devtree(struct i2c_client *client) +{ + struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client); + struct device_node *pp; + int r; + + pp = client->dev.of_node; + if (!pp) + return -ENODEV; + + r = of_get_named_gpio(pp, "enable-gpios", 0); + if (r == -EPROBE_DEFER) + r = of_get_named_gpio(pp, "enable-gpios", 0); + if (r < 0) { + nfc_err(&client->dev, "Failed to get EN gpio, error: %d\n", r); + return r; + } + phy->gpio_en = r; + + r = of_get_named_gpio(pp, "firmware-gpios", 0); + if (r == -EPROBE_DEFER) + r = of_get_named_gpio(pp, "firmware-gpios", 0); + if (r < 0) { + nfc_err(&client->dev, "Failed to get FW gpio, error: %d\n", r); + return r; + } + phy->gpio_fw = r; + + r = irq_of_parse_and_map(pp, 0); + if (r < 0) { + nfc_err(&client->dev, "Unable to get irq, error: %d\n", r); + return r; + } + client->irq = r; + + return 0; +} + +#else + +static int nxp_nci_i2c_parse_devtree(struct i2c_client *client) +{ + return -ENODEV; +} + +#endif + +static int nxp_nci_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct nxp_nci_i2c_phy *phy; + struct nxp_nci_nfc_platform_data *pdata; + int r; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + nfc_err(&client->dev, "Need I2C_FUNC_I2C\n"); + r = -ENODEV; + goto probe_exit; + } + + phy = devm_kzalloc(&client->dev, sizeof(struct nxp_nci_i2c_phy), + GFP_KERNEL); + if (!phy) { + r = -ENOMEM; + goto probe_exit; + } + + phy->i2c_dev = client; + i2c_set_clientdata(client, phy); + + pdata = client->dev.platform_data; + + if (!pdata && client->dev.of_node) { + r = nxp_nci_i2c_parse_devtree(client); + if (r < 0) { + nfc_err(&client->dev, "Failed to get DT data\n"); + goto probe_exit; + } + } else if (pdata) { + phy->gpio_en = pdata->gpio_en; + phy->gpio_fw = pdata->gpio_fw; + client->irq = pdata->irq; + } else { + nfc_err(&client->dev, "No platform data\n"); + r = -EINVAL; + goto probe_exit; + } + + r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en, + GPIOF_OUT_INIT_LOW, "nxp_nci_en"); + if (r < 0) + goto probe_exit; + + r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw, + GPIOF_OUT_INIT_LOW, "nxp_nci_fw"); + if (r < 0) + goto probe_exit; + + r = nxp_nci_probe(phy, &client->dev, &i2c_phy_ops, + NXP_NCI_I2C_MAX_PAYLOAD, &phy->ndev); + if (r < 0) + goto probe_exit; + + r = request_threaded_irq(client->irq, NULL, + nxp_nci_i2c_irq_thread_fn, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + NXP_NCI_I2C_DRIVER_NAME, phy); + if (r < 0) + nfc_err(&client->dev, "Unable to register IRQ handler\n"); + +probe_exit: + return r; +} + +static int nxp_nci_i2c_remove(struct i2c_client *client) +{ + struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client); + + nxp_nci_remove(phy->ndev); + free_irq(client->irq, phy); + + return 0; +} + +static struct i2c_device_id nxp_nci_i2c_id_table[] = { + {"nxp-nci_i2c", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, nxp_nci_i2c_id_table); + +static const struct of_device_id of_nxp_nci_i2c_match[] = { + { .compatible = "nxp,nxp-nci-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_nxp_nci_i2c_match); + +static struct i2c_driver nxp_nci_i2c_driver = { + .driver = { + .name = NXP_NCI_I2C_DRIVER_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(of_nxp_nci_i2c_match), + }, + .probe = nxp_nci_i2c_probe, + .id_table = nxp_nci_i2c_id_table, + .remove = nxp_nci_i2c_remove, +}; + +module_i2c_driver(nxp_nci_i2c_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("I2C driver for NXP NCI NFC controllers"); +MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>"); |