drivers/mfd/atmel-hlcdc.c

Source file repositories/reference/linux-study-clean/drivers/mfd/atmel-hlcdc.c

File Facts

System
Linux kernel
Corpus path
drivers/mfd/atmel-hlcdc.c
Extension
.c
Size
4324 bytes
Lines
170
Domain
Driver Families
Bucket
drivers/mfd
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 atmel_hlcdc_regmap {
	void __iomem *regs;
	struct device *dev;
};

static const struct mfd_cell atmel_hlcdc_cells[] = {
	{
		.name = "atmel-hlcdc-pwm",
		.of_compatible = "atmel,hlcdc-pwm",
	},
	{
		.name = "atmel-hlcdc-dc",
		.of_compatible = "atmel,hlcdc-display-controller",
	},
};

static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
					unsigned int val)
{
	struct atmel_hlcdc_regmap *hregmap = context;

	if (reg <= ATMEL_HLCDC_DIS) {
		u32 status;
		int ret;

		ret = readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
						status,
						!(status & ATMEL_HLCDC_SIP),
						1, 100);
		if (ret) {
			dev_err(hregmap->dev,
				"Timeout! Clock domain synchronization is in progress!\n");
			return ret;
		}
	}

	writel(val, hregmap->regs + reg);

	return 0;
}

static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
				       unsigned int *val)
{
	struct atmel_hlcdc_regmap *hregmap = context;

	*val = readl(hregmap->regs + reg);

	return 0;
}

static const struct regmap_config atmel_hlcdc_regmap_config = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = 4,
	.max_register = ATMEL_HLCDC_REG_MAX,
	.reg_write = regmap_atmel_hlcdc_reg_write,
	.reg_read = regmap_atmel_hlcdc_reg_read,
	.fast_io = true,
};

static int atmel_hlcdc_probe(struct platform_device *pdev)
{
	struct atmel_hlcdc_regmap *hregmap;
	struct device *dev = &pdev->dev;
	struct atmel_hlcdc *hlcdc;

	hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
	if (!hregmap)
		return -ENOMEM;

	hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
	if (!hlcdc)
		return -ENOMEM;

	hregmap->regs = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(hregmap->regs))
		return PTR_ERR(hregmap->regs);

	hregmap->dev = &pdev->dev;

	hlcdc->irq = platform_get_irq(pdev, 0);
	if (hlcdc->irq < 0)
		return hlcdc->irq;

	hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
	if (IS_ERR(hlcdc->periph_clk)) {
		dev_err(dev, "failed to get peripheral clock\n");
		return PTR_ERR(hlcdc->periph_clk);
	}

Annotation

Implementation Notes