I am having trouble understanding how the device tree works, or in particular why this driver will not be initialized. This is at the core of the Rockchip provider for Android, version 3.10
drivers / watchdog / rk29_wdt.c (reduced for readability)
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);
}
and this is soc dtsi
arch / hands / downloads / 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";
};
however, the .probe function of the driver is never called. It is compiled and the __init function is called. I suspect there is something to do if the device tree entry does not match? Maybe this is a problem?
Or is there anything else that works before .probe that determines if the driver should continue?
Also, I'm not sure how a flattened tree works, so maybe this is relevant:
arch / arm / mash-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