// SPDX-License-Identifier: GPL-2.0-or-later /* * I2C Link Layer for Samsung S3FWRN5 NCI based Driver * * Copyright (C) 2015 Samsung Electrnoics * Robert Baldyga */ #include #include #include #include #include #include #include #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 const 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 ");