I rewrote a driver with reference to time.c, and the main contents are as follows：
// get irq
gpt->irq=platform_get_irq(pdev,0);
if (gpt->irq<0) {
dev_err(&pdev->dev, "can't get irq number\n");
return gpt->irq;
}
ret=devm_request_irq(&pdev->dev,gpt->irq,gpt->irq_handler,0,pdev->name,gpt);
if (ret) {
dev_err(&pdev->dev, "can't claim irq %d\n", gpt->irq);
goto exit;
}
// get IO
gpt->gpio_pin=of_get_named_gpio(pdev->dev.of_node,"capture-gpios",0);
if (!gpio_is_valid(gpt->gpio_pin)) {
dev_err(&pdev->dev, "invalid GPIO pin\n");
ret = -EINVAL;
goto exit;
}
ret=devm_gpio_request_one(&pdev->dev,gpt->gpio_pin,GPIOF_DIR_IN,pdev->name);
if (ret) {
dev_err(&pdev->dev, "failed to request GPIO pin\n");
goto exit;
}
/*
* Initialise to a known state (all timers off, and timing reset)
*/
__raw_writel(V2_TCTL_SWR,gpt->base + MXC_TCTL);
while(__raw_readl(gpt->base + MXC_TCTL) & V2_TCTL_SWR);
__raw_writel(0, gpt->base + MXC_TCTL);
__raw_writel(0, gpt->base + MXC_TPRER); /* see datasheet note */
dev_info(&pdev->dev,"gpt ipgclk is %ldHZ\r\n",clk_get_rate(gpt->ipg_clk));
dev_info(&pdev->dev,"gpt perclk is %ldHZ\r\n",clk_get_rate(gpt->per_clk));
tctl_val = V2_TCTL_CLK_IPG | V2_TCTL_ENMOD |V2_TCTL_WAITEN | V2_TCTL_STOPEN;
__raw_writel((clk_get_rate(gpt->ipg_clk)/1000000)<<V2_TPRER_PRE,gpt->base + MXC_TPRER); //66 div
__raw_writel(tctl_val, gpt->base + MXC_TCTL);
//clear intbit
__raw_writel(0,gpt->base + V2_SR);
The device tree is as follows:
&gpt2 {
compatible = "ainuode,gpt2";
pinctrl-name = "default";
pinctrl-0 = <&pinctrl_gpt2cap>;
reg = <0x020e8000 0x4000>;
interrupts = <GIC_SPI 109 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks IMX6UL_CLK_IPG>,
<&clks IMX6UL_CLK_GPT2_BUS>;
clock-names = "ipg", "per";
capture-gpios = <&gpio1 11 GPIO_ACTIVE_HIGH>;
status = "okay";
};
pinctrl_gpt2cap: capgrp{
fsl,pin=<
MX6UL_PAD_JTAG_TMS__GPT2_CAPTURE1 0x1b0b1
>;
};
There are also some, configuration interrupt enables, input modes, etc., which are also verified to be successful and will not be posted here.
I have checked that the register configuration is correct. I hope you can answer it. Thank you very much and wish you all the best.
