1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-lpss-platform.c b/drivers/pwm/pwm-lpss-platform.c
new file mode 100644
index 000000000..c48c6f2b2
--- /dev/null
+++ b/drivers/pwm/pwm-lpss-platform.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Low Power Subsystem PWM controller driver
+ *
+ * Copyright (C) 2014, Intel Corporation
+ *
+ * Derived from the original pwm-lpss.c
+ */
+
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/property.h>
+
+#include "pwm-lpss.h"
+
+
+static int pwm_lpss_probe_platform(struct platform_device *pdev)
+{
+	const struct pwm_lpss_boardinfo *info;
+	struct pwm_lpss_chip *lpwm;
+	void __iomem *base;
+
+	info = device_get_match_data(&pdev->dev);
+	if (!info)
+		return -ENODEV;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	lpwm = pwm_lpss_probe(&pdev->dev, base, info);
+	if (IS_ERR(lpwm))
+		return PTR_ERR(lpwm);
+
+	platform_set_drvdata(pdev, lpwm);
+
+	/*
+	 * On Cherry Trail devices the GFX0._PS0 AML checks if the controller
+	 * is on and if it is not on it turns it on and restores what it
+	 * believes is the correct state to the PWM controller.
+	 * Because of this we must disallow direct-complete, which keeps the
+	 * controller (runtime)suspended on resume, to avoid 2 issues:
+	 * 1. The controller getting turned on without the linux-pm code
+	 *    knowing about this. On devices where the controller is unused
+	 *    this causes it to stay on during the next suspend causing high
+	 *    battery drain (because S0i3 is not reached)
+	 * 2. The state restoring code unexpectedly messing with the controller
+	 *
+	 * Leaving the controller runtime-suspended (skipping runtime-resume +
+	 * normal-suspend) during suspend is fine.
+	 */
+	if (info->other_devices_aml_touches_pwm_regs)
+		dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE|
+						    DPM_FLAG_SMART_SUSPEND);
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+}
+
+static int pwm_lpss_remove_platform(struct platform_device *pdev)
+{
+	pm_runtime_disable(&pdev->dev);
+	return 0;
+}
+
+static const struct acpi_device_id pwm_lpss_acpi_match[] = {
+	{ "80860F09", (unsigned long)&pwm_lpss_byt_info },
+	{ "80862288", (unsigned long)&pwm_lpss_bsw_info },
+	{ "80862289", (unsigned long)&pwm_lpss_bsw_info },
+	{ "80865AC8", (unsigned long)&pwm_lpss_bxt_info },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
+
+static struct platform_driver pwm_lpss_driver_platform = {
+	.driver = {
+		.name = "pwm-lpss",
+		.acpi_match_table = pwm_lpss_acpi_match,
+	},
+	.probe = pwm_lpss_probe_platform,
+	.remove = pwm_lpss_remove_platform,
+};
+module_platform_driver(pwm_lpss_driver_platform);
+
+MODULE_DESCRIPTION("PWM platform driver for Intel LPSS");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(PWM_LPSS);
+MODULE_ALIAS("platform:pwm-lpss");