diff options
Diffstat (limited to 'drivers/nfc/nfcmrvl/i2c.c')
| -rw-r--r-- | drivers/nfc/nfcmrvl/i2c.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/nfc/nfcmrvl/i2c.c b/drivers/nfc/nfcmrvl/i2c.c new file mode 100644 index 000000000..97600826a --- /dev/null +++ b/drivers/nfc/nfcmrvl/i2c.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Marvell NFC-over-I2C driver: I2C interface related functions + * + * Copyright (C) 2015, Marvell International Ltd. + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/i2c.h> +#include <linux/nfc.h> +#include <linux/delay.h> +#include <linux/of_irq.h> +#include <net/nfc/nci.h> +#include <net/nfc/nci_core.h> +#include "nfcmrvl.h" + +struct nfcmrvl_i2c_drv_data { + unsigned long flags; + struct device *dev; + struct i2c_client *i2c; + struct nfcmrvl_private *priv; +}; + +static int nfcmrvl_i2c_read(struct nfcmrvl_i2c_drv_data *drv_data, + struct sk_buff **skb) +{ + int ret; + struct nci_ctrl_hdr nci_hdr; + + /* Read NCI header to know the payload size */ + ret = i2c_master_recv(drv_data->i2c, (u8 *)&nci_hdr, NCI_CTRL_HDR_SIZE); + if (ret != NCI_CTRL_HDR_SIZE) { + nfc_err(&drv_data->i2c->dev, "cannot read NCI header\n"); + return -EBADMSG; + } + + *skb = nci_skb_alloc(drv_data->priv->ndev, + nci_hdr.plen + NCI_CTRL_HDR_SIZE, GFP_KERNEL); + if (!*skb) + return -ENOMEM; + + /* Copy NCI header into the SKB */ + skb_put_data(*skb, &nci_hdr, NCI_CTRL_HDR_SIZE); + + if (nci_hdr.plen) { + /* Read the NCI payload */ + ret = i2c_master_recv(drv_data->i2c, + skb_put(*skb, nci_hdr.plen), + nci_hdr.plen); + + if (ret != nci_hdr.plen) { + nfc_err(&drv_data->i2c->dev, + "Invalid frame payload length: %u (expected %u)\n", + ret, nci_hdr.plen); + kfree_skb(*skb); + return -EBADMSG; + } + } + + return 0; +} + +static irqreturn_t nfcmrvl_i2c_int_irq_thread_fn(int irq, void *drv_data_ptr) +{ + struct nfcmrvl_i2c_drv_data *drv_data = drv_data_ptr; + struct sk_buff *skb = NULL; + int ret; + + if (!drv_data->priv) + return IRQ_HANDLED; + + if (test_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags)) + return IRQ_HANDLED; + + ret = nfcmrvl_i2c_read(drv_data, &skb); + + switch (ret) { + case -EREMOTEIO: + set_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags); + break; + case -ENOMEM: + case -EBADMSG: + nfc_err(&drv_data->i2c->dev, "read failed %d\n", ret); + break; + default: + if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0) + nfc_err(&drv_data->i2c->dev, "corrupted RX packet\n"); + break; + } + return IRQ_HANDLED; +} + +static int nfcmrvl_i2c_nci_open(struct nfcmrvl_private *priv) +{ + struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data; + + if (!drv_data) + return -ENODEV; + + return 0; +} + +static int nfcmrvl_i2c_nci_close(struct nfcmrvl_private *priv) +{ + return 0; +} + +static int nfcmrvl_i2c_nci_send(struct nfcmrvl_private *priv, + struct sk_buff *skb) +{ + struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data; + int ret; + + if (test_bit(NFCMRVL_PHY_ERROR, &priv->flags)) { + kfree_skb(skb); + return -EREMOTEIO; + } + + ret = i2c_master_send(drv_data->i2c, skb->data, skb->len); + + /* Retry if chip was in standby */ + if (ret == -EREMOTEIO) { + nfc_info(drv_data->dev, "chip may sleep, retry\n"); + usleep_range(6000, 10000); + ret = i2c_master_send(drv_data->i2c, skb->data, skb->len); + } + + if (ret >= 0) { + if (ret != skb->len) { + nfc_err(drv_data->dev, + "Invalid length sent: %u (expected %u)\n", + ret, skb->len); + ret = -EREMOTEIO; + } else + ret = 0; + } + + if (ret) { + kfree_skb(skb); + return ret; + } + + consume_skb(skb); + return 0; +} + +static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv, + const void *param) +{ +} + +static const struct nfcmrvl_if_ops i2c_ops = { + .nci_open = nfcmrvl_i2c_nci_open, + .nci_close = nfcmrvl_i2c_nci_close, + .nci_send = nfcmrvl_i2c_nci_send, + .nci_update_config = nfcmrvl_i2c_nci_update_config, +}; + +static int nfcmrvl_i2c_parse_dt(struct device_node *node, + struct nfcmrvl_platform_data *pdata) +{ + int ret; + + ret = nfcmrvl_parse_dt(node, pdata); + if (ret < 0) { + pr_err("Failed to get generic entries\n"); + return ret; + } + + if (of_find_property(node, "i2c-int-falling", NULL)) + pdata->irq_polarity = IRQF_TRIGGER_FALLING; + else + pdata->irq_polarity = IRQF_TRIGGER_RISING; + + ret = irq_of_parse_and_map(node, 0); + if (!ret) { + pr_err("Unable to get irq\n"); + return -EINVAL; + } + pdata->irq = ret; + + return 0; +} + +static int nfcmrvl_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + const struct nfcmrvl_platform_data *pdata; + struct nfcmrvl_i2c_drv_data *drv_data; + struct nfcmrvl_platform_data config; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + nfc_err(&client->dev, "Need I2C_FUNC_I2C\n"); + return -ENODEV; + } + + drv_data = devm_kzalloc(&client->dev, sizeof(*drv_data), GFP_KERNEL); + if (!drv_data) + return -ENOMEM; + + drv_data->i2c = client; + drv_data->dev = &client->dev; + drv_data->priv = NULL; + + i2c_set_clientdata(client, drv_data); + + pdata = client->dev.platform_data; + + if (!pdata && client->dev.of_node) + if (nfcmrvl_i2c_parse_dt(client->dev.of_node, &config) == 0) + pdata = &config; + + if (!pdata) + return -EINVAL; + + /* Request the read IRQ */ + ret = devm_request_threaded_irq(&drv_data->i2c->dev, pdata->irq, + NULL, nfcmrvl_i2c_int_irq_thread_fn, + pdata->irq_polarity | IRQF_ONESHOT, + "nfcmrvl_i2c_int", drv_data); + if (ret < 0) { + nfc_err(&drv_data->i2c->dev, + "Unable to register IRQ handler\n"); + return ret; + } + + drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_I2C, + drv_data, &i2c_ops, + &drv_data->i2c->dev, pdata); + + if (IS_ERR(drv_data->priv)) + return PTR_ERR(drv_data->priv); + + drv_data->priv->support_fw_dnld = true; + + return 0; +} + +static void nfcmrvl_i2c_remove(struct i2c_client *client) +{ + struct nfcmrvl_i2c_drv_data *drv_data = i2c_get_clientdata(client); + + nfcmrvl_nci_unregister_dev(drv_data->priv); +} + + +static const struct of_device_id of_nfcmrvl_i2c_match[] __maybe_unused = { + { .compatible = "marvell,nfc-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_nfcmrvl_i2c_match); + +static const struct i2c_device_id nfcmrvl_i2c_id_table[] = { + { "nfcmrvl_i2c", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, nfcmrvl_i2c_id_table); + +static struct i2c_driver nfcmrvl_i2c_driver = { + .probe = nfcmrvl_i2c_probe, + .id_table = nfcmrvl_i2c_id_table, + .remove = nfcmrvl_i2c_remove, + .driver = { + .name = "nfcmrvl_i2c", + .of_match_table = of_match_ptr(of_nfcmrvl_i2c_match), + }, +}; + +module_i2c_driver(nfcmrvl_i2c_driver); + +MODULE_AUTHOR("Marvell International Ltd."); +MODULE_DESCRIPTION("Marvell NFC-over-I2C driver"); +MODULE_LICENSE("GPL v2"); |