Armadilloフォーラム

#imx8_ldb_enable()
#~\imx-boot-2020.04-at6\uboot-imx\drivers\video\nxp\imx\imx8_lvds.c
int imx8_ldb_enable(struct udevice *dev, int panel_bpp,
		      const struct display_timing *timing)
{
	struct imx8_ldb_priv *priv = dev_get_priv(dev);
	int ret;
 
	if (dev->platdata == NULL) {
		imx8_ldb_soc_setup(dev, timing->pixelclock.typ);
		imx8_ldb_configure(dev);
	} else {
 
		display_enable(dev->parent, panel_bpp, &priv->timings);
 
		if (IS_ENABLED(CONFIG_VIDEO_BRIDGE)) {
			if (priv->conn_dev &&
				device_get_uclass_id(priv->conn_dev) == UCLASS_VIDEO_BRIDGE) {
				ret = video_bridge_set_backlight(priv->conn_dev, 80);
				if (ret) {
					dev_err(dev, "fail to set backlight\n");
					return ret;
				}
			}
		}
	}
 
	return 0;
}
 
#uclass_first_device()
#~\imx-boot-2020.04-at6\uboot-imx\include\dm\uclass.h
/**
 * uclass_first_device() - Get the first device in a uclass
 *
 * The device returned is probed if necessary, and ready for use
 *
 * This function is useful to start iterating through a list of devices which
 * are functioning correctly and can be probed.
 *
 * @id: Uclass ID to look up
 * @devp: Returns pointer to the first device in that uclass if no error
 * occurred, or NULL if there is no first device, or an error occurred with
 * that device.
 * @return 0 if OK (found or not found), other -ve on error
 */
int uclass_first_device(enum uclass_id id, struct udevice **devp);
 
#uclass_id
#~\imx-boot-2020.04-at6\uboot-imx\include\dm\uclass-id.h
enum uclass_id {
　　[省略]
	/* These are used internally by driver model */
	/* U-Boot uclasses start here - in alphabetical order */
	UCLASS_ACPI_PMC,	/* (x86) Power-management controller (PMC) */
	UCLASS_ADC,		/* Analog-to-digital converter */
	UCLASS_AHCI,		/* SATA disk controller */
	UCLASS_AUDIO_CODEC,	/* Audio codec with control and data path */
	UCLASS_AXI,		/* AXI bus */
	UCLASS_BLK,		/* Block device */
	UCLASS_BOARD,		/* Device information from hardware */
	UCLASS_BOOTCOUNT,       /* Bootcount backing store */
	UCLASS_CACHE,		/* Cache controller */
	UCLASS_CLK,		/* Clock source, e.g. used by peripherals */
	UCLASS_CPU,		/* CPU, typically part of an SoC */
	UCLASS_CROS_EC,		/* Chrome OS EC */
	UCLASS_DISPLAY,		/* Display (e.g. DisplayPort, HDMI) */
	UCLASS_DSI_HOST,	/* Display Serial Interface host */
	UCLASS_DMA,		/* Direct Memory Access */
	UCLASS_DSA,		/* Distributed (Ethernet) Switch Architecture */
	UCLASS_EFI,		/* EFI managed devices */
	UCLASS_ETH,		/* Ethernet device */
	UCLASS_ETH_PHY,		/* Ethernet PHY device */
	UCLASS_FIRMWARE,	/* Firmware */
	UCLASS_FS_FIRMWARE_LOADER,		/* Generic loader */
	UCLASS_GPIO,		/* Bank of general-purpose I/O pins */
	UCLASS_HWSPINLOCK,	/* Hardware semaphores */
	UCLASS_I2C,		/* I2C bus */
	UCLASS_I2C_EEPROM,	/* I2C EEPROM device */
	UCLASS_I2C_GENERIC,	/* Generic I2C device */
	UCLASS_I2C_MUX,		/* I2C multiplexer */
	UCLASS_I2S,		/* I2S bus */
	UCLASS_IDE,		/* IDE device */
	UCLASS_IRQ,		/* Interrupt controller */
	UCLASS_KEYBOARD,	/* Keyboard input device */
	UCLASS_LED,		/* Light-emitting diode (LED) */
	UCLASS_LPC,		/* x86 'low pin count' interface */
	UCLASS_MAILBOX,		/* Mailbox controller */
	UCLASS_MASS_STORAGE,	/* Mass storage device */
	UCLASS_MDIO,		/* MDIO bus */
	UCLASS_MDIO_MUX,	/* MDIO MUX/switch */
	UCLASS_MISC,		/* Miscellaneous device */
	UCLASS_MMC,		/* SD / MMC card or chip */
	UCLASS_MOD_EXP,		/* RSA Mod Exp device */
	UCLASS_MTD,		/* Memory Technology Device (MTD) device */
	UCLASS_NOP,		/* No-op devices */
	UCLASS_NORTHBRIDGE,	/* Intel Northbridge / SDRAM controller */
	UCLASS_NVME,		/* NVM Express device */
	UCLASS_P2SB,		/* (x86) Primary-to-Sideband Bus */
	UCLASS_PANEL,		/* Display panel, such as an LCD */
	UCLASS_PANEL_BACKLIGHT,	/* Backlight controller for panel */
	UCLASS_PCH,		/* x86 platform controller hub */
	UCLASS_PCI,		/* PCI bus */
	UCLASS_PCI_EP,		/* PCI endpoint device */
	UCLASS_PCI_GENERIC,	/* Generic PCI bus device */
	UCLASS_PHY,		/* Physical Layer (PHY) device */
	UCLASS_PINCONFIG,	/* Pin configuration node device */
	UCLASS_PINCTRL,		/* Pinctrl (pin muxing/configuration) device */
	UCLASS_PMIC,		/* PMIC I/O device */
	UCLASS_POWER_DOMAIN,	/* (SoC) Power domains */
	UCLASS_PWM,		/* Pulse-width modulator */
	UCLASS_PWRSEQ,		/* Power sequence device */
	UCLASS_RAM,		/* RAM controller */
	UCLASS_REGULATOR,	/* Regulator device */
	UCLASS_REMOTEPROC,	/* Remote Processor device */
	UCLASS_RESET,		/* Reset controller device */
	UCLASS_RNG,		/* Random Number Generator */
	UCLASS_RTC,		/* Real time clock device */
	UCLASS_SCSI,		/* SCSI device */
	UCLASS_SERIAL,		/* Serial UART */
	UCLASS_SIMPLE_BUS,	/* Bus with child devices */
	UCLASS_SMEM,		/* Shared memory interface */
	UCLASS_SOUND,		/* Playing simple sounds */
	UCLASS_SPI,		/* SPI bus */
	UCLASS_SPI_FLASH,	/* SPI flash */
	UCLASS_SPI_GENERIC,	/* Generic SPI flash target */
	UCLASS_SPMI,		/* System Power Management Interface bus */
	UCLASS_SYSCON,		/* System configuration device */
	UCLASS_SYSRESET,	/* System reset device */
	UCLASS_TEE,		/* Trusted Execution Environment device */
	UCLASS_THERMAL,		/* Thermal sensor */
	UCLASS_TIMER,		/* Timer device */
	UCLASS_TPM,		/* Trusted Platform Module TIS interface */
	UCLASS_UFS,		/* Universal Flash Storage */
	UCLASS_USB,		/* USB bus */
	UCLASS_USB_DEV_GENERIC,	/* USB generic device */
	UCLASS_USB_HUB,		/* USB hub */
	UCLASS_USB_GADGET_GENERIC,	/* USB generic device */
	UCLASS_VIDEO,		/* Video or LCD device */
	UCLASS_VIDEO_BRIDGE,	/* Video bridge, e.g. DisplayPort to LVDS */
	UCLASS_VIDEO_CONSOLE,	/* Text console driver for video device */
	UCLASS_VIDEO_OSD,	/* On-screen display */
	UCLASS_VIRTIO,		/* VirtIO transport device */
	UCLASS_W1,		/* Dallas 1-Wire bus */
	UCLASS_W1_EEPROM,	/* one-wire EEPROMs */
	UCLASS_WDT,		/* Watchdog Timer driver */
 
	UCLASS_COUNT,
	UCLASS_INVALID = -1,
};