drivers/phy/st/phy-stih407-usb.c

Source file repositories/reference/linux-study-clean/drivers/phy/st/phy-stih407-usb.c

File Facts

System
Linux kernel
Corpus path
drivers/phy/st/phy-stih407-usb.c
Extension
.c
Size
4504 bytes
Lines
165
Domain
Driver Families
Bucket
drivers/phy
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 stih407_usb2_picophy {
	struct phy *phy;
	struct regmap *regmap;
	struct device *dev;
	struct reset_control *rstc;
	struct reset_control *rstport;
	int ctrl;
	int param;
};

static int stih407_usb2_pico_ctrl(struct stih407_usb2_picophy *phy_dev)
{
	reset_control_deassert(phy_dev->rstc);

	return regmap_update_bits(phy_dev->regmap, phy_dev->ctrl,
				  STIH407_USB_PICOPHY_CTRL_PORT_MASK,
				  STIH407_USB_PICOPHY_CTRL_PORT_CONF);
}

static int stih407_usb2_init_port(struct phy *phy)
{
	int ret;
	struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);

	stih407_usb2_pico_ctrl(phy_dev);

	ret = regmap_update_bits(phy_dev->regmap,
				 phy_dev->param,
				 STIH407_USB_PICOPHY_PARAM_MASK,
				 STIH407_USB_PICOPHY_PARAM_DEF);
	if (ret)
		return ret;

	return reset_control_deassert(phy_dev->rstport);
}

static int stih407_usb2_exit_port(struct phy *phy)
{
	struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);

	/*
	 * Only port reset is asserted, phy global reset is kept untouched
	 * as other ports may still be active. When all ports are in reset
	 * state, assumption is made that power will be cut off on the phy, in
	 * case of suspend for instance. Theoretically, asserting individual
	 * reset (like here) or global reset should be equivalent.
	 */
	return reset_control_assert(phy_dev->rstport);
}

static const struct phy_ops stih407_usb2_picophy_data = {
	.init = stih407_usb2_init_port,
	.exit = stih407_usb2_exit_port,
	.owner = THIS_MODULE,
};

static int stih407_usb2_picophy_probe(struct platform_device *pdev)
{
	struct stih407_usb2_picophy *phy_dev;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct phy_provider *phy_provider;
	unsigned int syscon_args[2];
	struct phy *phy;

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

	phy_dev->dev = dev;
	dev_set_drvdata(dev, phy_dev);

	phy_dev->rstc = devm_reset_control_get_shared(dev, "global");
	if (IS_ERR(phy_dev->rstc)) {
		dev_err(dev, "failed to ctrl picoPHY reset\n");
		return PTR_ERR(phy_dev->rstc);
	}

	phy_dev->rstport = devm_reset_control_get_exclusive(dev, "port");
	if (IS_ERR(phy_dev->rstport)) {
		dev_err(dev, "failed to ctrl picoPHY reset\n");
		return PTR_ERR(phy_dev->rstport);
	}

	/* Reset port by default: only deassert it in phy init */
	reset_control_assert(phy_dev->rstport);

	phy_dev->regmap = syscon_regmap_lookup_by_phandle_args(np, "st,syscfg",
							       2, syscon_args);
	if (IS_ERR(phy_dev->regmap)) {

Annotation

Implementation Notes