4 files changed, 130 insertions, 1 deletions

diff --git a/drivers/firmware/samsung/Makefile b/drivers/firmware/samsung/Makefile
index 7b4c9f6f34f5..80d4f89b33a9 100644
--- a/drivers/firmware/samsung/Makefile
+++ b/drivers/firmware/samsung/Makefile
@@ -1,4 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-acpm-protocol-objs			:= exynos-acpm.o exynos-acpm-pmic.o
+acpm-protocol-objs			:= exynos-acpm.o
+acpm-protocol-objs			+= exynos-acpm-pmic.o
+acpm-protocol-objs			+= exynos-acpm-dvfs.o
 obj-$(CONFIG_EXYNOS_ACPM_PROTOCOL)	+= acpm-protocol.o
diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.c b/drivers/firmware/samsung/exynos-acpm-dvfs.c
new file mode 100644
index 000000000000..1c5b2b143bcc
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-dvfs.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2025 Linaro Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/ktime.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include "exynos-acpm.h"
+#include "exynos-acpm-dvfs.h"
+
+#define ACPM_DVFS_ID			GENMASK(11, 0)
+#define ACPM_DVFS_REQ_TYPE		GENMASK(15, 0)
+
+#define ACPM_DVFS_FREQ_REQ		0
+#define ACPM_DVFS_FREQ_GET		1
+
+static void acpm_dvfs_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdlen,
+			       unsigned int acpm_chan_id, bool response)
+{
+	xfer->acpm_chan_id = acpm_chan_id;
+	xfer->txd = cmd;
+	xfer->txlen = cmdlen;
+
+	if (response) {
+		xfer->rxd = cmd;
+		xfer->rxlen = cmdlen;
+	}
+}
+
+static void acpm_dvfs_init_set_rate_cmd(u32 cmd[4], unsigned int clk_id,
+					unsigned long rate)
+{
+	cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id);
+	cmd[1] = rate / HZ_PER_KHZ;
+	cmd[2] = FIELD_PREP(ACPM_DVFS_REQ_TYPE, ACPM_DVFS_FREQ_REQ);
+	cmd[3] = ktime_to_ms(ktime_get());
+}
+
+int acpm_dvfs_set_rate(const struct acpm_handle *handle,
+		       unsigned int acpm_chan_id, unsigned int clk_id,
+		       unsigned long rate)
+{
+	struct acpm_xfer xfer = {0};
+	u32 cmd[4];
+
+	acpm_dvfs_init_set_rate_cmd(cmd, clk_id, rate);
+	acpm_dvfs_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id, false);
+
+	return acpm_do_xfer(handle, &xfer);
+}
+
+static void acpm_dvfs_init_get_rate_cmd(u32 cmd[4], unsigned int clk_id)
+{
+	cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id);
+	cmd[2] = FIELD_PREP(ACPM_DVFS_REQ_TYPE, ACPM_DVFS_FREQ_GET);
+	cmd[3] = ktime_to_ms(ktime_get());
+}
+
+unsigned long acpm_dvfs_get_rate(const struct acpm_handle *handle,
+				 unsigned int acpm_chan_id, unsigned int clk_id)
+{
+	struct acpm_xfer xfer;
+	unsigned int cmd[4] = {0};
+	int ret;
+
+	acpm_dvfs_init_get_rate_cmd(cmd, clk_id);
+	acpm_dvfs_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id, true);
+
+	ret = acpm_do_xfer(handle, &xfer);
+	if (ret)
+		return 0;
+
+	return xfer.rxd[1] * HZ_PER_KHZ;
+}
diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.h b/drivers/firmware/samsung/exynos-acpm-dvfs.h
new file mode 100644
index 000000000000..9f2778e649c9
--- /dev/null
+++ b/drivers/firmware/samsung/exynos-acpm-dvfs.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2025 Linaro Ltd.
+ */
+#ifndef __EXYNOS_ACPM_DVFS_H__
+#define __EXYNOS_ACPM_DVFS_H__
+
+#include <linux/types.h>
+
+struct acpm_handle;
+
+int acpm_dvfs_set_rate(const struct acpm_handle *handle,
+		       unsigned int acpm_chan_id, unsigned int id,
+		       unsigned long rate);
+unsigned long acpm_dvfs_get_rate(const struct acpm_handle *handle,
+				 unsigned int acpm_chan_id,
+				 unsigned int clk_id);
+
+#endif /* __EXYNOS_ACPM_DVFS_H__ */
diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index 3a69fe3234c7..0cb269c70460 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -29,6 +29,7 @@
 #include <linux/types.h>
 
 #include "exynos-acpm.h"
+#include "exynos-acpm-dvfs.h"
 #include "exynos-acpm-pmic.h"
 
 #define ACPM_PROTOCOL_SEQNUM		GENMASK(21, 16)
@@ -176,9 +177,11 @@ struct acpm_info {
 /**
  * struct acpm_match_data - of_device_id data.
  * @initdata_base:	offset in SRAM where the channels configuration resides.
+ * @acpm_clk_dev_name:	base name for the ACPM clocks device that we're registering.
  */
 struct acpm_match_data {
 	loff_t initdata_base;
+	const char *acpm_clk_dev_name;
 };
 
 #define client_to_acpm_chan(c) container_of(c, struct acpm_chan, cl)
@@ -590,8 +593,12 @@ static int acpm_channels_init(struct acpm_info *acpm)
  */
 static void acpm_setup_ops(struct acpm_info *acpm)
 {
+	struct acpm_dvfs_ops *dvfs_ops = &acpm->handle.ops.dvfs_ops;
 	struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic_ops;
 
+	dvfs_ops->set_rate = acpm_dvfs_set_rate;
+	dvfs_ops->get_rate = acpm_dvfs_get_rate;
+
 	pmic_ops->read_reg = acpm_pmic_read_reg;
 	pmic_ops->bulk_read = acpm_pmic_bulk_read;
 	pmic_ops->write_reg = acpm_pmic_write_reg;
@@ -599,9 +606,15 @@ static void acpm_setup_ops(struct acpm_info *acpm)
 	pmic_ops->update_reg = acpm_pmic_update_reg;
 }
 
+static void acpm_clk_pdev_unregister(void *data)
+{
+	platform_device_unregister(data);
+}
+
 static int acpm_probe(struct platform_device *pdev)
 {
 	const struct acpm_match_data *match_data;
+	struct platform_device *acpm_clk_pdev;
 	struct device *dev = &pdev->dev;
 	struct device_node *shmem;
 	struct acpm_info *acpm;
@@ -642,6 +655,18 @@ static int acpm_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, acpm);
 
+	acpm_clk_pdev = platform_device_register_data(dev,
+						match_data->acpm_clk_dev_name,
+						PLATFORM_DEVID_NONE, NULL, 0);
+	if (IS_ERR(acpm_clk_pdev))
+		return dev_err_probe(dev, PTR_ERR(acpm_clk_pdev),
+				     "Failed to register ACPM clocks device.\n");
+
+	ret = devm_add_action_or_reset(dev, acpm_clk_pdev_unregister,
+				       acpm_clk_pdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to add devm action.\n");
+
 	return devm_of_platform_populate(dev);
 }
 
@@ -741,6 +766,7 @@ EXPORT_SYMBOL_GPL(devm_acpm_get_by_node);
 
 static const struct acpm_match_data acpm_gs101 = {
 	.initdata_base = ACPM_GS101_INITDATA_BASE,
+	.acpm_clk_dev_name = "gs101-acpm-clk",
 };
 
 static const struct of_device_id acpm_match[] = {