| /* |
| * I2C Link Layer for Samsung S3FWRN5 NCI based Driver |
| * |
| * Copyright (C) 2015 Samsung Electrnoics |
| * Robert Baldyga <r.baldyga@samsung.com> |
| * |
| * 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 or later, 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/>. |
| */ |
| |
| #include <linux/i2c.h> |
| #include <linux/gpio.h> |
| #include <linux/delay.h> |
| #include <linux/of_gpio.h> |
| #include <linux/of_irq.h> |
| #include <linux/module.h> |
| |
| #include <net/nfc/nfc.h> |
| |
| #include "s3fwrn5.h" |
| |
| #define S3FWRN5_I2C_DRIVER_NAME "s3fwrn5_i2c" |
| |
| #define S3FWRN5_I2C_MAX_PAYLOAD 32 |
| #define S3FWRN5_EN_WAIT_TIME 150 |
| |
| struct s3fwrn5_i2c_phy { |
| struct i2c_client *i2c_dev; |
| struct nci_dev *ndev; |
| |
| int gpio_en; |
| int gpio_fw_wake; |
| |
| struct mutex mutex; |
| |
| enum s3fwrn5_mode mode; |
| unsigned int irq_skip:1; |
| }; |
| |
| static void s3fwrn5_i2c_set_wake(void *phy_id, bool wake) |
| { |
| struct s3fwrn5_i2c_phy *phy = phy_id; |
| |
| mutex_lock(&phy->mutex); |
| gpio_set_value(phy->gpio_fw_wake, wake); |
| msleep(S3FWRN5_EN_WAIT_TIME/2); |
| mutex_unlock(&phy->mutex); |
| } |
| |
| static void s3fwrn5_i2c_set_mode(void *phy_id, enum s3fwrn5_mode mode) |
| { |
| struct s3fwrn5_i2c_phy *phy = phy_id; |
| |
| mutex_lock(&phy->mutex); |
| |
| if (phy->mode == mode) |
| goto out; |
| |
| phy->mode = mode; |
| |
| gpio_set_value(phy->gpio_en, 1); |
| gpio_set_value(phy->gpio_fw_wake, 0); |
| if (mode == S3FWRN5_MODE_FW) |
| gpio_set_value(phy->gpio_fw_wake, 1); |
| |
| if (mode != S3FWRN5_MODE_COLD) { |
| msleep(S3FWRN5_EN_WAIT_TIME); |
| gpio_set_value(phy->gpio_en, 0); |
| msleep(S3FWRN5_EN_WAIT_TIME/2); |
| } |
| |
| phy->irq_skip = true; |
| |
| out: |
| mutex_unlock(&phy->mutex); |
| } |
| |
| static enum s3fwrn5_mode s3fwrn5_i2c_get_mode(void *phy_id) |
| { |
| struct s3fwrn5_i2c_phy *phy = phy_id; |
| enum s3fwrn5_mode mode; |
| |
| mutex_lock(&phy->mutex); |
| |
| mode = phy->mode; |
| |
| mutex_unlock(&phy->mutex); |
| |
| return mode; |
| } |
| |
| static int s3fwrn5_i2c_write(void *phy_id, struct sk_buff *skb) |
| { |
| struct s3fwrn5_i2c_phy *phy = phy_id; |
| int ret; |
| |
| mutex_lock(&phy->mutex); |
| |
| phy->irq_skip = false; |
| |
| ret = i2c_master_send(phy->i2c_dev, skb->data, skb->len); |
| if (ret == -EREMOTEIO) { |
| /* Retry, chip was in standby */ |
| usleep_range(110000, 120000); |
| ret = i2c_master_send(phy->i2c_dev, skb->data, skb->len); |
| } |
| |
| mutex_unlock(&phy->mutex); |
| |
| if (ret < 0) |
| return ret; |
| |
| if (ret != skb->len) |
| return -EREMOTEIO; |
| |
| return 0; |
| } |
| |
| static const struct s3fwrn5_phy_ops i2c_phy_ops = { |
| .set_wake = s3fwrn5_i2c_set_wake, |
| .set_mode = s3fwrn5_i2c_set_mode, |
| .get_mode = s3fwrn5_i2c_get_mode, |
| .write = s3fwrn5_i2c_write, |
| }; |
| |
| static int s3fwrn5_i2c_read(struct s3fwrn5_i2c_phy *phy) |
| { |
| struct sk_buff *skb; |
| size_t hdr_size; |
| size_t data_len; |
| char hdr[4]; |
| int ret; |
| |
| hdr_size = (phy->mode == S3FWRN5_MODE_NCI) ? |
| NCI_CTRL_HDR_SIZE : S3FWRN5_FW_HDR_SIZE; |
| ret = i2c_master_recv(phy->i2c_dev, hdr, hdr_size); |
| if (ret < 0) |
| return ret; |
| |
| if (ret < hdr_size) |
| return -EBADMSG; |
| |
| data_len = (phy->mode == S3FWRN5_MODE_NCI) ? |
| ((struct nci_ctrl_hdr *)hdr)->plen : |
| ((struct s3fwrn5_fw_header *)hdr)->len; |
| |
| skb = alloc_skb(hdr_size + data_len, GFP_KERNEL); |
| if (!skb) |
| return -ENOMEM; |
| |
| skb_put_data(skb, hdr, hdr_size); |
| |
| if (data_len == 0) |
| goto out; |
| |
| ret = i2c_master_recv(phy->i2c_dev, skb_put(skb, data_len), data_len); |
| if (ret != data_len) { |
| kfree_skb(skb); |
| return -EBADMSG; |
| } |
| |
| out: |
| return s3fwrn5_recv_frame(phy->ndev, skb, phy->mode); |
| } |
| |
| static irqreturn_t s3fwrn5_i2c_irq_thread_fn(int irq, void *phy_id) |
| { |
| struct s3fwrn5_i2c_phy *phy = phy_id; |
| int ret = 0; |
| |
| if (!phy || !phy->ndev) { |
| WARN_ON_ONCE(1); |
| return IRQ_NONE; |
| } |
| |
| mutex_lock(&phy->mutex); |
| |
| if (phy->irq_skip) |
| goto out; |
| |
| switch (phy->mode) { |
| case S3FWRN5_MODE_NCI: |
| case S3FWRN5_MODE_FW: |
| ret = s3fwrn5_i2c_read(phy); |
| break; |
| case S3FWRN5_MODE_COLD: |
| ret = -EREMOTEIO; |
| break; |
| } |
| |
| out: |
| mutex_unlock(&phy->mutex); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int s3fwrn5_i2c_parse_dt(struct i2c_client *client) |
| { |
| struct s3fwrn5_i2c_phy *phy = i2c_get_clientdata(client); |
| struct device_node *np = client->dev.of_node; |
| |
| if (!np) |
| return -ENODEV; |
| |
| phy->gpio_en = of_get_named_gpio(np, "s3fwrn5,en-gpios", 0); |
| if (!gpio_is_valid(phy->gpio_en)) |
| return -ENODEV; |
| |
| phy->gpio_fw_wake = of_get_named_gpio(np, "s3fwrn5,fw-gpios", 0); |
| if (!gpio_is_valid(phy->gpio_fw_wake)) |
| return -ENODEV; |
| |
| return 0; |
| } |
| |
| static int s3fwrn5_i2c_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct s3fwrn5_i2c_phy *phy; |
| int ret; |
| |
| phy = devm_kzalloc(&client->dev, sizeof(*phy), GFP_KERNEL); |
| if (!phy) |
| return -ENOMEM; |
| |
| mutex_init(&phy->mutex); |
| phy->mode = S3FWRN5_MODE_COLD; |
| phy->irq_skip = true; |
| |
| phy->i2c_dev = client; |
| i2c_set_clientdata(client, phy); |
| |
| ret = s3fwrn5_i2c_parse_dt(client); |
| if (ret < 0) |
| return ret; |
| |
| ret = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en, |
| GPIOF_OUT_INIT_HIGH, "s3fwrn5_en"); |
| if (ret < 0) |
| return ret; |
| |
| ret = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw_wake, |
| GPIOF_OUT_INIT_LOW, "s3fwrn5_fw_wake"); |
| if (ret < 0) |
| return ret; |
| |
| ret = s3fwrn5_probe(&phy->ndev, phy, &phy->i2c_dev->dev, &i2c_phy_ops, |
| S3FWRN5_I2C_MAX_PAYLOAD); |
| if (ret < 0) |
| return ret; |
| |
| ret = devm_request_threaded_irq(&client->dev, phy->i2c_dev->irq, NULL, |
| s3fwrn5_i2c_irq_thread_fn, IRQF_TRIGGER_HIGH | IRQF_ONESHOT, |
| S3FWRN5_I2C_DRIVER_NAME, phy); |
| if (ret) |
| s3fwrn5_remove(phy->ndev); |
| |
| return ret; |
| } |
| |
| static int s3fwrn5_i2c_remove(struct i2c_client *client) |
| { |
| struct s3fwrn5_i2c_phy *phy = i2c_get_clientdata(client); |
| |
| s3fwrn5_remove(phy->ndev); |
| |
| return 0; |
| } |
| |
| static struct i2c_device_id s3fwrn5_i2c_id_table[] = { |
| {S3FWRN5_I2C_DRIVER_NAME, 0}, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(i2c, s3fwrn5_i2c_id_table); |
| |
| static const struct of_device_id of_s3fwrn5_i2c_match[] = { |
| { .compatible = "samsung,s3fwrn5-i2c", }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, of_s3fwrn5_i2c_match); |
| |
| static struct i2c_driver s3fwrn5_i2c_driver = { |
| .driver = { |
| .owner = THIS_MODULE, |
| .name = S3FWRN5_I2C_DRIVER_NAME, |
| .of_match_table = of_match_ptr(of_s3fwrn5_i2c_match), |
| }, |
| .probe = s3fwrn5_i2c_probe, |
| .remove = s3fwrn5_i2c_remove, |
| .id_table = s3fwrn5_i2c_id_table, |
| }; |
| |
| module_i2c_driver(s3fwrn5_i2c_driver); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("I2C driver for Samsung S3FWRN5"); |
| MODULE_AUTHOR("Robert Baldyga <r.baldyga@samsung.com>"); |