我无法理解设备树的工作原理,或者具体来说为什么该驱动程序无法初始化。这是在 android 版本 3.10 的 rockchip 供应商内核中
驱动程序/看门狗/rk29_wdt.c(为了可读性而减少)
static const struct of_device_id of_rk29_wdt_match[] = {
{ .compatible = "rockchip,watch dog" }
};
static struct platform_driver rk29_wdt_driver = {
.probe = rk29_wdt_probe,
[..]
.of_match_table = of_rk29_wdt_match,
.name = "rk29-wdt",
},
};
static int __init watchdog_init(void)
{
printk("watchdog_init\n");
return platform_driver_register(&rk29_wdt_driver);
}
这是 soc dtsi
拱门/arm/boot/dts/rk3288.dtsi
watchdog: wdt@2004c000 {
compatible = "rockchip,watch dog";
reg = <0xff800000 0x100>;
clocks = <&pclk_pd_alive>;
clock-names = "pclk_wdt";
interrupts = <GIC_SPI 79 IRQ_TYPE_LEVEL_HIGH>;
rockchip,irq = <0>;
rockchip,timeout = <2>;
rockchip,atboot = <1>;
rockchip,debug = <0>;
status = "okay";
};
但是,驱动程序的 .probe 函数永远不会被调用。它被编译并调用 __init 函数。我怀疑这与设备树条目不匹配有关?也许空间是一个问题?
或者是否有其他东西在 .probe 之前运行来确定驱动程序是否应该继续?
另外我不确定扁平树是如何工作的,所以也许这是相关的:
拱门/手臂/mach-rockchip/rk3288
DT_MACHINE_START(RK3288_DT, "Rockchip RK3288 (Flattened Device Tree)")
.smp = smp_ops(rockchip_smp_ops),
.map_io = rk3288_dt_map_io,
.init_time = rk3288_dt_init_timer,
.dt_compat = rk3288_dt_compat,
.init_late = rk3288_init_late,
.reserve = rk3288_reserve,
.restart = rk3288_restart,
MACHINE_END