drivers/tty/serial/mvebu-uart.c

Source file repositories/reference/linux-study-clean/drivers/tty/serial/mvebu-uart.c

File Facts

System
Linux kernel
Corpus path
drivers/tty/serial/mvebu-uart.c
Extension
.c
Size
42178 bytes
Lines
1532
Domain
Driver Families
Bucket
drivers/tty
Inferred role
Driver Families: implementation source
Status
source 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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct uart_regs_layout {
	unsigned int rbr;
	unsigned int tsh;
	unsigned int ctrl;
	unsigned int intr;
};

/* Diverging flags */
struct uart_flags {
	unsigned int ctrl_tx_rdy_int;
	unsigned int ctrl_rx_rdy_int;
	unsigned int stat_tx_rdy;
	unsigned int stat_rx_rdy;
};

/* Driver data, a structure for each UART port */
struct mvebu_uart_driver_data {
	bool is_ext;
	struct uart_regs_layout regs;
	struct uart_flags flags;
};

/* Saved registers during suspend */
struct mvebu_uart_pm_regs {
	unsigned int rbr;
	unsigned int tsh;
	unsigned int ctrl;
	unsigned int intr;
	unsigned int stat;
	unsigned int brdv;
	unsigned int osamp;
};

/* MVEBU UART driver structure */
struct mvebu_uart {
	struct uart_port *port;
	struct clk *clk;
	int irq[UART_IRQ_COUNT];
	struct mvebu_uart_driver_data *data;
#if defined(CONFIG_PM)
	struct mvebu_uart_pm_regs pm_regs;
#endif /* CONFIG_PM */
};

static struct mvebu_uart *to_mvuart(struct uart_port *port)
{
	return (struct mvebu_uart *)port->private_data;
}

#define IS_EXTENDED(port) (to_mvuart(port)->data->is_ext)

#define UART_RBR(port) (to_mvuart(port)->data->regs.rbr)
#define UART_TSH(port) (to_mvuart(port)->data->regs.tsh)
#define UART_CTRL(port) (to_mvuart(port)->data->regs.ctrl)
#define UART_INTR(port) (to_mvuart(port)->data->regs.intr)

#define CTRL_TX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_tx_rdy_int)
#define CTRL_RX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_rx_rdy_int)
#define STAT_TX_RDY(port) (to_mvuart(port)->data->flags.stat_tx_rdy)
#define STAT_RX_RDY(port) (to_mvuart(port)->data->flags.stat_rx_rdy)

static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];

static DEFINE_SPINLOCK(mvebu_uart_lock);

/* Core UART Driver Operations */
static unsigned int mvebu_uart_tx_empty(struct uart_port *port)
{
	unsigned long flags;
	unsigned int st;

	uart_port_lock_irqsave(port, &flags);
	st = readl(port->membase + UART_STAT);
	uart_port_unlock_irqrestore(port, flags);

	return (st & STAT_TX_EMP) ? TIOCSER_TEMT : 0;
}

static unsigned int mvebu_uart_get_mctrl(struct uart_port *port)
{
	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
}

static void mvebu_uart_set_mctrl(struct uart_port *port,
				 unsigned int mctrl)
{
/*
 * Even if we do not support configuring the modem control lines, this
 * function must be proided to the serial core
 */

Annotation

Implementation Notes