drivers/spi/spi-coldfire-qspi.c

Source file repositories/reference/linux-study-clean/drivers/spi/spi-coldfire-qspi.c

File Facts

System
Linux kernel
Corpus path
drivers/spi/spi-coldfire-qspi.c
Extension
.c
Size
12715 bytes
Lines
507
Domain
Driver Families
Bucket
drivers/spi
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 mcfqspi {
	void __iomem *iobase;
	int irq;
	struct clk *clk;
	struct mcfqspi_cs_control *cs_control;

	wait_queue_head_t waitq;
};

static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QMR);
}

static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
}

static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
{
	return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
}

static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QWR);
}

static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QIR);
}

static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QAR);
}

static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
{
	writew(val, mcfqspi->iobase + MCFQSPI_QDR);
}

static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
{
	return readw(mcfqspi->iobase + MCFQSPI_QDR);
}

static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
			    bool cs_high)
{
	mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
}

static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
				bool cs_high)
{
	mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
}

static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
{
	return (mcfqspi->cs_control->setup) ?
		mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
}

static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
{
	if (mcfqspi->cs_control->teardown)
		mcfqspi->cs_control->teardown(mcfqspi->cs_control);
}

static u8 mcfqspi_qmr_baud(u32 speed_hz)
{
	return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
}

static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
{
	return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
}

static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
{
	struct mcfqspi *mcfqspi = dev_id;

	/* clear interrupt */
	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
	wake_up(&mcfqspi->waitq);

Annotation

Implementation Notes