drivers/nfc/pn544/pn544.c

File Facts

System

Linux kernel

Corpus path

drivers/nfc/pn544/pn544.c

Extension

.c

Size

24144 bytes

Lines

985

Domain

Driver Families

Bucket

drivers/nfc

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/delay.h
• linux/slab.h
• linux/module.h
• linux/nfc.h
• net/nfc/hci.h
• pn544.h

Detected Declarations

• struct pn544_hci_info
• enum pn544_state
• function pn544_hci_open
• function pn544_hci_close
• function pn544_hci_ready
• function pn544_hci_xmit
• function pn544_hci_start_poll
• function pn544_hci_dep_link_up
• function pn544_hci_dep_link_down
• function pn544_hci_target_from_gate
• function pn544_hci_complete_target_discovered
• function pn544_hci_data_exchange_cb
• function pn544_hci_im_transceive
• function pn544_hci_tm_send
• function pn544_hci_check_presence
• function pn544_hci_event_received
• function pn544_hci_fw_download
• function pn544_hci_discover_se
• function pn544_hci_enable_se
• function pn544_hci_disable_se
• function pn544_hci_probe
• function pn544_hci_remove
• export pn544_hci_probe
• export pn544_hci_remove

Annotated Snippet

struct pn544_hci_info {
	const struct nfc_phy_ops *phy_ops;
	void *phy_id;

	struct nfc_hci_dev *hdev;

	enum pn544_state state;

	struct mutex info_lock;

	int async_cb_type;
	data_exchange_cb_t async_cb;
	void *async_cb_context;

	fw_download_t fw_download;
};

static int pn544_hci_open(struct nfc_hci_dev *hdev)
{
	struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);
	int r = 0;

	mutex_lock(&info->info_lock);

	if (info->state != PN544_ST_COLD) {
		r = -EBUSY;
		goto out;
	}

	r = info->phy_ops->enable(info->phy_id);

	if (r == 0)
		info->state = PN544_ST_READY;

out:
	mutex_unlock(&info->info_lock);
	return r;
}

static void pn544_hci_close(struct nfc_hci_dev *hdev)
{
	struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

	mutex_lock(&info->info_lock);

	if (info->state == PN544_ST_COLD)
		goto out;

	info->phy_ops->disable(info->phy_id);

	info->state = PN544_ST_COLD;

out:
	mutex_unlock(&info->info_lock);
}

static int pn544_hci_ready(struct nfc_hci_dev *hdev)
{
	struct sk_buff *skb;
	static struct hw_config {
		u8 adr[2];
		u8 value;
	} hw_config[] = {
		{{0x9f, 0x9a}, 0x00},

		{{0x98, 0x10}, 0xbc},

		{{0x9e, 0x71}, 0x00},

		{{0x98, 0x09}, 0x00},

		{{0x9e, 0xb4}, 0x00},

		{{0x9c, 0x01}, 0x08},

		{{0x9e, 0xaa}, 0x01},

		{{0x9b, 0xd1}, 0x17},
		{{0x9b, 0xd2}, 0x58},
		{{0x9b, 0xd3}, 0x10},
		{{0x9b, 0xd4}, 0x47},
		{{0x9b, 0xd5}, 0x0c},
		{{0x9b, 0xd6}, 0x37},
		{{0x9b, 0xdd}, 0x33},

		{{0x9b, 0x84}, 0x00},
		{{0x99, 0x81}, 0x79},
		{{0x99, 0x31}, 0x79},

		{{0x98, 0x00}, 0x3f},

Annotation

• Immediate include surface: `linux/delay.h`, `linux/slab.h`, `linux/module.h`, `linux/nfc.h`, `net/nfc/hci.h`, `pn544.h`.
• Detected declarations: `struct pn544_hci_info`, `enum pn544_state`, `function pn544_hci_open`, `function pn544_hci_close`, `function pn544_hci_ready`, `function pn544_hci_xmit`, `function pn544_hci_start_poll`, `function pn544_hci_dep_link_up`, `function pn544_hci_dep_link_down`, `function pn544_hci_target_from_gate`.
• Atlas domain: Driver Families / drivers/nfc.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.