drivers/mfd/88pm80x.c

Source file repositories/reference/linux-study-clean/drivers/mfd/88pm80x.c

File Facts

System
Linux kernel
Corpus path
drivers/mfd/88pm80x.c
Extension
.c
Size
3792 bytes
Lines
160
Domain
Driver Families
Bucket
drivers/mfd
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 pm80x_chip_mapping {
	unsigned int	id;
	int		type;
};

static struct pm80x_chip_mapping chip_mapping[] = {
	/* 88PM800 chip id number */
	{0x3,	CHIP_PM800},
	/* 88PM805 chip id number */
	{0x0,	CHIP_PM805},
	/* 88PM860 chip id number */
	{0x4,	CHIP_PM860},
};

/*
 * workaround: some registers needed by pm805 are defined in pm800, so
 * need to use this global variable to maintain the relation between
 * pm800 and pm805. would remove it after HW chip fixes the issue.
 */
static struct pm80x_chip *g_pm80x_chip;

const struct regmap_config pm80x_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};
EXPORT_SYMBOL_GPL(pm80x_regmap_config);


int pm80x_init(struct i2c_client *client)
{
	struct pm80x_chip *chip;
	struct regmap *map;
	unsigned int val;
	int i, ret = 0;

	chip =
	    devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
	if (!chip)
		return -ENOMEM;

	map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
	if (IS_ERR(map)) {
		ret = PTR_ERR(map);
		dev_err(&client->dev, "Failed to allocate register map: %d\n",
			ret);
		return ret;
	}

	chip->client = client;
	chip->regmap = map;

	chip->irq = client->irq;

	chip->dev = &client->dev;
	i2c_set_clientdata(chip->client, chip);

	ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
	if (ret < 0) {
		dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
		return ret;
	}

	for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
		if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
			chip->type = chip_mapping[i].type;
			break;
		}
	}

	if (i == ARRAY_SIZE(chip_mapping)) {
		dev_err(chip->dev,
			"Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
		return -EINVAL;
	}

	device_init_wakeup(&client->dev, 1);

	/*
	 * workaround: set g_pm80x_chip to the first probed chip. if the
	 * second chip is probed, just point to the companion to each
	 * other so that pm805 can access those specific register. would
	 * remove it after HW chip fixes the issue.
	 */
	if (!g_pm80x_chip)
		g_pm80x_chip = chip;
	else {
		chip->companion = g_pm80x_chip->client;
		g_pm80x_chip->companion = chip->client;
	}

Annotation

Implementation Notes