sound/soc/ti/omap-mcpdm.c

Source file repositories/reference/linux-study-clean/sound/soc/ti/omap-mcpdm.c

File Facts

System
Linux kernel
Corpus path
sound/soc/ti/omap-mcpdm.c
Extension
.c
Size
16590 bytes
Lines
602
Domain
Driver Families
Bucket
sound/soc
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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mcpdm_link_config {
	u32 link_mask; /* channel mask for the direction */
	u32 threshold; /* FIFO threshold */
};

struct omap_mcpdm {
	struct device *dev;
	unsigned long phys_base;
	void __iomem *io_base;
	int irq;
	struct pm_qos_request pm_qos_req;
	int latency[2];

	struct mutex mutex;

	/* Playback/Capture configuration */
	struct mcpdm_link_config config[2];

	/* McPDM dn offsets for rx1, and 2 channels */
	u32 dn_rx_offset;

	/* McPDM needs to be restarted due to runtime reconfiguration */
	bool restart;

	/* pm state for suspend/resume handling */
	int pm_active_count;

	struct snd_dmaengine_dai_dma_data dma_data[2];
};

/*
 * Stream DMA parameters
 */

static inline void omap_mcpdm_write(struct omap_mcpdm *mcpdm, u16 reg, u32 val)
{
	writel_relaxed(val, mcpdm->io_base + reg);
}

static inline int omap_mcpdm_read(struct omap_mcpdm *mcpdm, u16 reg)
{
	return readl_relaxed(mcpdm->io_base + reg);
}

#ifdef DEBUG
static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm)
{
	dev_dbg(mcpdm->dev, "***********************\n");
	dev_dbg(mcpdm->dev, "IRQSTATUS_RAW:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS_RAW));
	dev_dbg(mcpdm->dev, "IRQSTATUS:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS));
	dev_dbg(mcpdm->dev, "IRQENABLE_SET:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_SET));
	dev_dbg(mcpdm->dev, "IRQENABLE_CLR:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_CLR));
	dev_dbg(mcpdm->dev, "IRQWAKE_EN: 0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQWAKE_EN));
	dev_dbg(mcpdm->dev, "DMAENABLE_SET: 0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_SET));
	dev_dbg(mcpdm->dev, "DMAENABLE_CLR:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_CLR));
	dev_dbg(mcpdm->dev, "DMAWAKEEN:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAWAKEEN));
	dev_dbg(mcpdm->dev, "CTRL:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL));
	dev_dbg(mcpdm->dev, "DN_DATA:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_DN_DATA));
	dev_dbg(mcpdm->dev, "UP_DATA: 0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_UP_DATA));
	dev_dbg(mcpdm->dev, "FIFO_CTRL_DN: 0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_DN));
	dev_dbg(mcpdm->dev, "FIFO_CTRL_UP:  0x%04x\n",
			omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_UP));
	dev_dbg(mcpdm->dev, "***********************\n");
}
#else
static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm) {}
#endif

/*
 * Enables the transfer through the PDM interface to/from the Phoenix
 * codec by enabling the corresponding UP or DN channels.
 */
static void omap_mcpdm_start(struct omap_mcpdm *mcpdm)
{
	u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
	u32 link_mask = mcpdm->config[0].link_mask | mcpdm->config[1].link_mask;

	ctrl |= (MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);

Annotation

Implementation Notes