1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/acpi/dptf/dptf_pch_fivr.c b/drivers/acpi/dptf/dptf_pch_fivr.c
new file mode 100644
index 000000000000..4ab288827747
--- /dev/null
+++ b/drivers/acpi/dptf/dptf_pch_fivr.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * dptf_pch_fivr:  DPTF PCH FIVR Participant driver
+ * Copyright (c) 2020, Intel Corporation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+/*
+ * Presentation of attributes which are defined for INT1045
+ * They are:
+ * freq_mhz_low_clock : Set PCH FIVR switching freq for
+ *			FIVR clock 19.2MHz and 24MHz
+ * freq_mhz_high_clock : Set PCH FIVR switching freq for
+ *			FIVR clock 38.4MHz
+ */
+#define PCH_FIVR_SHOW(name, method) \
+static ssize_t name##_show(struct device *dev,\
+			   struct device_attribute *attr,\
+			   char *buf)\
+{\
+	struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
+	unsigned long long val;\
+	acpi_status status;\
+\
+	status = acpi_evaluate_integer(acpi_dev->handle, #method,\
+				       NULL, &val);\
+	if (ACPI_SUCCESS(status))\
+		return sprintf(buf, "%d\n", (int)val);\
+	else\
+		return -EINVAL;\
+}
+
+#define PCH_FIVR_STORE(name, method) \
+static ssize_t name##_store(struct device *dev,\
+			    struct device_attribute *attr,\
+			    const char *buf, size_t count)\
+{\
+	struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
+	acpi_status status;\
+	u32 val;\
+\
+	if (kstrtouint(buf, 0, &val) < 0)\
+		return -EINVAL;\
+\
+	status = acpi_execute_simple_method(acpi_dev->handle, #method, val);\
+	if (ACPI_SUCCESS(status))\
+		return count;\
+\
+	return -EINVAL;\
+}
+
+PCH_FIVR_SHOW(freq_mhz_low_clock, GFC0)
+PCH_FIVR_SHOW(freq_mhz_high_clock, GFC1)
+PCH_FIVR_STORE(freq_mhz_low_clock, RFC0)
+PCH_FIVR_STORE(freq_mhz_high_clock, RFC1)
+
+static DEVICE_ATTR_RW(freq_mhz_low_clock);
+static DEVICE_ATTR_RW(freq_mhz_high_clock);
+
+static struct attribute *fivr_attrs[] = {
+	&dev_attr_freq_mhz_low_clock.attr,
+	&dev_attr_freq_mhz_high_clock.attr,
+	NULL
+};
+
+static const struct attribute_group pch_fivr_attribute_group = {
+	.attrs = fivr_attrs,
+	.name = "pch_fivr_switch_frequency"
+};
+
+static int pch_fivr_add(struct platform_device *pdev)
+{
+	struct acpi_device *acpi_dev;
+	unsigned long long ptype;
+	acpi_status status;
+	int result;
+
+	acpi_dev = ACPI_COMPANION(&(pdev->dev));
+	if (!acpi_dev)
+		return -ENODEV;
+
+	status = acpi_evaluate_integer(acpi_dev->handle, "PTYP", NULL, &ptype);
+	if (ACPI_FAILURE(status) || ptype != 0x05)
+		return -ENODEV;
+
+	result = sysfs_create_group(&pdev->dev.kobj,
+				    &pch_fivr_attribute_group);
+	if (result)
+		return result;
+
+	platform_set_drvdata(pdev, acpi_dev);
+
+	return 0;
+}
+
+static int pch_fivr_remove(struct platform_device *pdev)
+{
+	sysfs_remove_group(&pdev->dev.kobj, &pch_fivr_attribute_group);
+
+	return 0;
+}
+
+static const struct acpi_device_id pch_fivr_device_ids[] = {
+	{"INTC1045", 0},
+	{"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, pch_fivr_device_ids);
+
+static struct platform_driver pch_fivr_driver = {
+	.probe = pch_fivr_add,
+	.remove = pch_fivr_remove,
+	.driver = {
+		.name = "DPTF PCH FIVR",
+		.acpi_match_table = pch_fivr_device_ids,
+	},
+};
+
+module_platform_driver(pch_fivr_driver);
+
+MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ACPI DPTF PCH FIVR driver");