On Fri, May 22, 2015 at 10:36:37PM +0800, Frank.Li at freescale.com wrote:

+static int imx_snvs_pwrkey_probe(struct platform_device *pdev)
+{
+	struct pwrkey_drv_data *pdata = NULL;
+	struct input_dev *input = NULL;
+	struct device_node *np, *snvs_np;
+	int error;
+
+	/* Get SNVS register Page */
+	np = pdev->dev.of_node;
+	if (!np)
+		return -ENODEV;
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	snvs_np = of_get_parent(pdev->dev.of_node);
+	if (!snvs_np)
+		return -ENODEV;
+
+	pdata->snvs = syscon_node_to_regmap(snvs_np);

Same here, I suggest you have a 'regmap' property and call
syscon_regmap_lookup_by_phandle() to get regmap.

Shawn

+	of_node_put(snvs_np);
+
+	if (!pdata->snvs) {
+		pr_err("Can't get snvs syscon\n");
+		return -ENODEV;
+	}
+
+	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode)) {
+		pdata->keycode = KEY_POWER;
+		dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
+	}
+
+	pdata->wakeup = of_property_read_bool(np, "wakeup");
+
+	pdata->irq = platform_get_irq(pdev, 0);
+	if (pdata->irq < 0) {
+		dev_err(&pdev->dev, "no irq defined in platform data\n");
+		return -EINVAL;
+	}
+
+	regmap_update_bits(pdata->snvs, SNVS_LPCR_REG, SNVS_LPCR_DEP_EN, SNVS_LPCR_DEP_EN);
+
+	/* clear the unexpected interrupt before driver ready */
+	regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
+
+	setup_timer(&pdata->check_timer,
+		    imx_imx_snvs_check_for_events, (unsigned long) pdata);
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input) {
+		dev_err(&pdev->dev, "failed to allocate the input device\n");
+		return -ENOMEM;
+	}
+
+	input->name = pdev->name;
+	input->phys = "snvs-pwrkey/input0";
+	input->id.bustype = BUS_HOST;
+
+	input_set_capability(input, EV_KEY, pdata->keycode);
+
+	/* input customer action to cancel release timer */
+	error = devm_add_action(&pdev->dev, imx_snvs_pwrkey_act, pdata);
+	if (error) {
+		dev_err(&pdev->dev, "failed to register remove action\n");
+		return error;
+	}
+
+	error = devm_request_irq(&pdev->dev, pdata->irq,
+			       imx_snvs_pwrkey_interrupt,
+			       0, pdev->name, pdev);
+
+	if (error) {
+		dev_err(&pdev->dev, "interrupt not available.\n");
+		return error;
+	}
+
+	error = input_register_device(input);
+	if (error < 0) {
+		dev_err(&pdev->dev, "failed to register input device\n");
+		input_free_device(input);
+		return error;
+	}
+
+	pdata->input = input;
+	platform_set_drvdata(pdev, pdata);
+
+	device_init_wakeup(&pdev->dev, pdata->wakeup);
+
+	return 0;
+}
+
+static int imx_snvs_pwrkey_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev))
+		enable_irq_wake(pdata->irq);
+
+	return 0;
+}
+
+static int imx_snvs_pwrkey_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev))
+		disable_irq_wake(pdata->irq);
+
+	return 0;
+}
+
+static const struct of_device_id imx_snvs_pwrkey_ids[] = {
+	{ .compatible = "fsl,sec-v4.0-pwrkey" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_snvs_pwrkey_ids);
+
+static SIMPLE_DEV_PM_OPS(imx_snvs_pwrkey_pm_ops, imx_snvs_pwrkey_suspend,
+				imx_snvs_pwrkey_resume);
+
+static struct platform_driver imx_snvs_pwrkey_driver = {
+	.driver = {
+		.name = "snvs_pwrkey",
+		.pm     = &imx_snvs_pwrkey_pm_ops,
+		.of_match_table = imx_snvs_pwrkey_ids,
+	},
+	.probe = imx_snvs_pwrkey_probe,
+};
+module_platform_driver(imx_snvs_pwrkey_driver);
+
+MODULE_AUTHOR("Freescale Semiconductor");
+MODULE_DESCRIPTION("i.MX snvs power key Driver");
+MODULE_LICENSE("GPL");
-- 
1.9.1