[PATCH 00/10] nvmem: patches(set 1) for 5.5

[PATCH 00/10] nvmem: patches(set 1) for 5.5

[Srinivas Kandagatla]

Hi Greg,

Here are some nvmem patches for 5.5 which includes:
- New provider for Rockchip OTP and Spreadtrum eFuse.
- Hole region support in imx scu driver.
- few trivial fixes.

Can you please queue them up for 5.5.

thanks,
srini

Baolin Wang (1):
  nvmem: sc27xx: Change to use devm_hwspin_lock_request_specific() to
    request one hwlock

Finley Xiao (1):
  nvmem: add Rockchip OTP driver

Freeman Liu (2):
  dt-bindings: nvmem: Add Spreadtrum eFuse controller documentation
  nvmem: sprd: Add Spreadtrum SoCs eFuse support

Heiko Stuebner (1):
  dt-bindings: nvmem: add binding for Rockchip OTP controller

Lucas Stach (1):
  nvmem: imx-ocotp: reset error status on probe

Peng Fan (2):
  nvmem: imx: scu: support hole region check
  nvmem: imx: scu: support write

Sebastian Reichel (1):
  nvmem: core: fix nvmem_cell_write inline function

Srinivas Kandagatla (1):
  nvmem: imx: scu: fix dependency in Kconfig

 .../bindings/nvmem/rockchip-otp.txt           |  25 ++
 .../devicetree/bindings/nvmem/sprd-efuse.txt  |  39 ++
 drivers/nvmem/Kconfig                         |  23 +
 drivers/nvmem/Makefile                        |   4 +
 drivers/nvmem/imx-ocotp-scu.c                 | 120 ++++-
 drivers/nvmem/imx-ocotp.c                     |   4 +
 drivers/nvmem/rockchip-otp.c                  | 268 +++++++++++
 drivers/nvmem/sc27xx-efuse.c                  |  13 +-
 drivers/nvmem/sprd-efuse.c                    | 424 ++++++++++++++++++
 include/linux/nvmem-consumer.h                |   2 +-
 10 files changed, 903 insertions(+), 19 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/nvmem/rockchip-otp.txt
 create mode 100644 Documentation/devicetree/bindings/nvmem/sprd-efuse.txt
 create mode 100644 drivers/nvmem/rockchip-otp.c
 create mode 100644 drivers/nvmem/sprd-efuse.c

-- 
2.21.0

[PATCH 01/10] nvmem: core: fix nvmem_cell_write inline function

[Srinivas Kandagatla]

From: Sebastian Reichel <sebastian.reichel@collabora.com>

nvmem_cell_write's buf argument uses different types based on
the configuration of CONFIG_NVMEM. The function prototype for
enabled NVMEM uses 'void *' type, but the static dummy function
for disabled NVMEM uses 'const char *' instead. Fix the different
behaviour by always expecting a 'void *' typed buf argument.

Fixes: 7a78a7f7695b ("power: reset: nvmem-reboot-mode: use NVMEM as reboot mode write interface")
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Han Nandor <nandor.han@vaisala.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-By: Han Nandor <nandor.han@vaisala.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 include/linux/nvmem-consumer.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h
index 8f8be5b00060..5c17cb733224 100644
--- a/include/linux/nvmem-consumer.h
+++ b/include/linux/nvmem-consumer.h
@@ -118,7 +118,7 @@ static inline void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len)
 }
 
 static inline int nvmem_cell_write(struct nvmem_cell *cell,
-				    const char *buf, size_t len)
+				   void *buf, size_t len)
 {
 	return -EOPNOTSUPP;
 }
-- 
2.21.0

[PATCH 02/10] nvmem: sc27xx: Change to use devm_hwspin_lock_request_specific() to request one hwlock

[Srinivas Kandagatla]

From: Baolin Wang <baolin.wang@linaro.org>

Change to use devm_hwspin_lock_request_specific() to help to simplify the
cleanup code for drivers requesting one hwlock. Thus we can remove the
redundant sc27xx_efuse_remove() and platform_set_drvdata().

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/sc27xx-efuse.c | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/drivers/nvmem/sc27xx-efuse.c b/drivers/nvmem/sc27xx-efuse.c
index c6ee21018d80..ab5e7e0bc3d8 100644
--- a/drivers/nvmem/sc27xx-efuse.c
+++ b/drivers/nvmem/sc27xx-efuse.c
@@ -211,7 +211,7 @@ static int sc27xx_efuse_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	efuse->hwlock = hwspin_lock_request_specific(ret);
+	efuse->hwlock = devm_hwspin_lock_request_specific(&pdev->dev, ret);
 	if (!efuse->hwlock) {
 		dev_err(&pdev->dev, "failed to request hwspinlock\n");
 		return -ENXIO;
@@ -219,7 +219,6 @@ static int sc27xx_efuse_probe(struct platform_device *pdev)
 
 	mutex_init(&efuse->mutex);
 	efuse->dev = &pdev->dev;
-	platform_set_drvdata(pdev, efuse);
 
 	econfig.stride = 1;
 	econfig.word_size = 1;
@@ -232,21 +231,12 @@ static int sc27xx_efuse_probe(struct platform_device *pdev)
 	nvmem = devm_nvmem_register(&pdev->dev, &econfig);
 	if (IS_ERR(nvmem)) {
 		dev_err(&pdev->dev, "failed to register nvmem config\n");
-		hwspin_lock_free(efuse->hwlock);
 		return PTR_ERR(nvmem);
 	}
 
 	return 0;
 }
 
-static int sc27xx_efuse_remove(struct platform_device *pdev)
-{
-	struct sc27xx_efuse *efuse = platform_get_drvdata(pdev);
-
-	hwspin_lock_free(efuse->hwlock);
-	return 0;
-}
-
 static const struct of_device_id sc27xx_efuse_of_match[] = {
 	{ .compatible = "sprd,sc2731-efuse" },
 	{ }
@@ -254,7 +244,6 @@ static const struct of_device_id sc27xx_efuse_of_match[] = {
 
 static struct platform_driver sc27xx_efuse_driver = {
 	.probe = sc27xx_efuse_probe,
-	.remove = sc27xx_efuse_remove,
 	.driver = {
 		.name = "sc27xx-efuse",
 		.of_match_table = sc27xx_efuse_of_match,
-- 
2.21.0

[PATCH 03/10] nvmem: imx: scu: support hole region check

[Srinivas Kandagatla]

From: Peng Fan <peng.fan@nxp.com>

Introduce HOLE/ECC_REGION flag and in_hole helper to ease the check
of hole region. The ECC_REGION is also introduced here which is
preparing for programming support. ECC_REGION could only be programmed
once, so need take care.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/imx-ocotp-scu.c | 47 +++++++++++++++++++++++++++++++----
 1 file changed, 42 insertions(+), 5 deletions(-)

diff --git a/drivers/nvmem/imx-ocotp-scu.c b/drivers/nvmem/imx-ocotp-scu.c
index 61a17f943f47..030e27ba4dfb 100644
--- a/drivers/nvmem/imx-ocotp-scu.c
+++ b/drivers/nvmem/imx-ocotp-scu.c
@@ -19,9 +19,20 @@ enum ocotp_devtype {
 	IMX8QM,
 };
 
+#define ECC_REGION	BIT(0)
+#define HOLE_REGION	BIT(1)
+
+struct ocotp_region {
+	u32 start;
+	u32 end;
+	u32 flag;
+};
+
 struct ocotp_devtype_data {
 	int devtype;
 	int nregs;
+	u32 num_region;
+	struct ocotp_region region[];
 };
 
 struct ocotp_priv {
@@ -38,13 +49,41 @@ struct imx_sc_msg_misc_fuse_read {
 static struct ocotp_devtype_data imx8qxp_data = {
 	.devtype = IMX8QXP,
 	.nregs = 800,
+	.num_region = 3,
+	.region = {
+		{0x10, 0x10f, ECC_REGION},
+		{0x110, 0x21F, HOLE_REGION},
+		{0x220, 0x31F, ECC_REGION},
+	},
 };
 
 static struct ocotp_devtype_data imx8qm_data = {
 	.devtype = IMX8QM,
 	.nregs = 800,
+	.num_region = 2,
+	.region = {
+		{0x10, 0x10f, ECC_REGION},
+		{0x1a0, 0x1ff, ECC_REGION},
+	},
 };
 
+static bool in_hole(void *context, u32 index)
+{
+	struct ocotp_priv *priv = context;
+	const struct ocotp_devtype_data *data = priv->data;
+	int i;
+
+	for (i = 0; i < data->num_region; i++) {
+		if (data->region[i].flag & HOLE_REGION) {
+			if ((index >= data->region[i].start) &&
+			    (index <= data->region[i].end))
+				return true;
+		}
+	}
+
+	return false;
+}
+
 static int imx_sc_misc_otp_fuse_read(struct imx_sc_ipc *ipc, u32 word,
 				     u32 *val)
 {
@@ -91,11 +130,9 @@ static int imx_scu_ocotp_read(void *context, unsigned int offset,
 	buf = p;
 
 	for (i = index; i < (index + count); i++) {
-		if (priv->data->devtype == IMX8QXP) {
-			if ((i > 271) && (i < 544)) {
-				*buf++ = 0;
-				continue;
-			}
+		if (in_hole(context, i)) {
+			*buf++ = 0;
+			continue;
 		}
 
 		ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, i, buf);
-- 
2.21.0

[PATCH 04/10] nvmem: imx: scu: support write

[Srinivas Kandagatla]

From: Peng Fan <peng.fan@nxp.com>

The fuse programming from non-secure world is blocked, so we could
only use Arm Trusted Firmware SIP call to let ATF program fuse.

Because there is ECC region that could only be programmed once,
so add a heler in_ecc to check the ecc region.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/imx-ocotp-scu.c | 73 ++++++++++++++++++++++++++++++++++-
 1 file changed, 72 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/imx-ocotp-scu.c b/drivers/nvmem/imx-ocotp-scu.c
index 030e27ba4dfb..03f1ab23ad51 100644
--- a/drivers/nvmem/imx-ocotp-scu.c
+++ b/drivers/nvmem/imx-ocotp-scu.c
@@ -7,6 +7,7 @@
  * Peng Fan <peng.fan@nxp.com>
  */
 
+#include <linux/arm-smccc.h>
 #include <linux/firmware/imx/sci.h>
 #include <linux/module.h>
 #include <linux/nvmem-provider.h>
@@ -14,6 +15,9 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
+#define IMX_SIP_OTP			0xC200000A
+#define IMX_SIP_OTP_WRITE		0x2
+
 enum ocotp_devtype {
 	IMX8QXP,
 	IMX8QM,
@@ -46,6 +50,8 @@ struct imx_sc_msg_misc_fuse_read {
 	u32 word;
 } __packed;
 
+static DEFINE_MUTEX(scu_ocotp_mutex);
+
 static struct ocotp_devtype_data imx8qxp_data = {
 	.devtype = IMX8QXP,
 	.nregs = 800,
@@ -84,6 +90,23 @@ static bool in_hole(void *context, u32 index)
 	return false;
 }
 
+static bool in_ecc(void *context, u32 index)
+{
+	struct ocotp_priv *priv = context;
+	const struct ocotp_devtype_data *data = priv->data;
+	int i;
+
+	for (i = 0; i < data->num_region; i++) {
+		if (data->region[i].flag & ECC_REGION) {
+			if ((index >= data->region[i].start) &&
+			    (index <= data->region[i].end))
+				return true;
+		}
+	}
+
+	return false;
+}
+
 static int imx_sc_misc_otp_fuse_read(struct imx_sc_ipc *ipc, u32 word,
 				     u32 *val)
 {
@@ -127,6 +150,8 @@ static int imx_scu_ocotp_read(void *context, unsigned int offset,
 	if (!p)
 		return -ENOMEM;
 
+	mutex_lock(&scu_ocotp_mutex);
+
 	buf = p;
 
 	for (i = index; i < (index + count); i++) {
@@ -137,6 +162,7 @@ static int imx_scu_ocotp_read(void *context, unsigned int offset,
 
 		ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, i, buf);
 		if (ret) {
+			mutex_unlock(&scu_ocotp_mutex);
 			kfree(p);
 			return ret;
 		}
@@ -145,18 +171,63 @@ static int imx_scu_ocotp_read(void *context, unsigned int offset,
 
 	memcpy(val, (u8 *)p + offset % 4, bytes);
 
+	mutex_unlock(&scu_ocotp_mutex);
+
 	kfree(p);
 
 	return 0;
 }
 
+static int imx_scu_ocotp_write(void *context, unsigned int offset,
+			       void *val, size_t bytes)
+{
+	struct ocotp_priv *priv = context;
+	struct arm_smccc_res res;
+	u32 *buf = val;
+	u32 tmp;
+	u32 index;
+	int ret;
+
+	/* allow only writing one complete OTP word at a time */
+	if ((bytes != 4) || (offset % 4))
+		return -EINVAL;
+
+	index = offset >> 2;
+
+	if (in_hole(context, index))
+		return -EINVAL;
+
+	if (in_ecc(context, index)) {
+		pr_warn("ECC region, only program once\n");
+		mutex_lock(&scu_ocotp_mutex);
+		ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, index, &tmp);
+		mutex_unlock(&scu_ocotp_mutex);
+		if (ret)
+			return ret;
+		if (tmp) {
+			pr_warn("ECC region, already has value: %x\n", tmp);
+			return -EIO;
+		}
+	}
+
+	mutex_lock(&scu_ocotp_mutex);
+
+	arm_smccc_smc(IMX_SIP_OTP, IMX_SIP_OTP_WRITE, index, *buf,
+		      0, 0, 0, 0, &res);
+
+	mutex_unlock(&scu_ocotp_mutex);
+
+	return res.a0;
+}
+
 static struct nvmem_config imx_scu_ocotp_nvmem_config = {
 	.name = "imx-scu-ocotp",
-	.read_only = true,
+	.read_only = false,
 	.word_size = 4,
 	.stride = 1,
 	.owner = THIS_MODULE,
 	.reg_read = imx_scu_ocotp_read,
+	.reg_write = imx_scu_ocotp_write,
 };
 
 static const struct of_device_id imx_scu_ocotp_dt_ids[] = {
-- 
2.21.0

[PATCH 05/10] nvmem: imx-ocotp: reset error status on probe

[Srinivas Kandagatla]

From: Lucas Stach <l.stach@pengutronix.de>

If software running before the OCOTP driver is loaded left the
controller with the error status pending, the driver will never
be able to complete the read timing setup. Reset the error status
on probe to make sure the controller is in usable state.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/imx-ocotp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index dff2f3c357f5..fc40555ca4cd 100644
--- a/drivers/nvmem/imx-ocotp.c
+++ b/drivers/nvmem/imx-ocotp.c
@@ -521,6 +521,10 @@ static int imx_ocotp_probe(struct platform_device *pdev)
 	if (IS_ERR(priv->clk))
 		return PTR_ERR(priv->clk);
 
+	clk_prepare_enable(priv->clk);
+	imx_ocotp_clr_err_if_set(priv->base);
+	clk_disable_unprepare(priv->clk);
+
 	priv->params = of_device_get_match_data(&pdev->dev);
 	imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
 	imx_ocotp_nvmem_config.dev = dev;
-- 
2.21.0

[PATCH 06/10] dt-bindings: nvmem: Add Spreadtrum eFuse controller documentation

[Srinivas Kandagatla]

From: Freeman Liu <freeman.liu@unisoc.com>

This patch adds the binding documentation for Spreadtrum eFuse controller.

Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 .../devicetree/bindings/nvmem/sprd-efuse.txt  | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/sprd-efuse.txt

diff --git a/Documentation/devicetree/bindings/nvmem/sprd-efuse.txt b/Documentation/devicetree/bindings/nvmem/sprd-efuse.txt
new file mode 100644
index 000000000000..96b6feec27f0
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/sprd-efuse.txt
@@ -0,0 +1,39 @@
+= Spreadtrum eFuse device tree bindings =
+
+Required properties:
+- compatible: Should be "sprd,ums312-efuse".
+- reg: Specify the address offset of efuse controller.
+- clock-names: Should be "enable".
+- clocks: The phandle and specifier referencing the controller's clock.
+- hwlocks: Reference to a phandle of a hwlock provider node.
+
+= Data cells =
+Are child nodes of eFuse, bindings of which as described in
+bindings/nvmem/nvmem.txt
+
+Example:
+
+	ap_efuse: efuse@32240000 {
+		compatible = "sprd,ums312-efuse";
+		reg = <0 0x32240000 0 0x10000>;
+		clock-names = "enable";
+		hwlocks = <&hwlock 8>;
+		clocks = <&aonapb_gate CLK_EFUSE_EB>;
+
+		/* Data cells */
+		thermal_calib: calib@10 {
+			reg = <0x10 0x2>;
+		};
+	};
+
+= Data consumers =
+Are device nodes which consume nvmem data cells.
+
+Example:
+
+	thermal {
+		...
+
+		nvmem-cells = <&thermal_calib>;
+		nvmem-cell-names = "calibration";
+	};
-- 
2.21.0

[PATCH 07/10] nvmem: sprd: Add Spreadtrum SoCs eFuse support

[Srinivas Kandagatla]

From: Freeman Liu <freeman.liu@unisoc.com>

The Spreadtrum eFuse controller is widely used to dump chip ID,
configuration setting, function select and so on, as well as
supporting one-time programming.

Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/Kconfig      |  11 +
 drivers/nvmem/Makefile     |   2 +
 drivers/nvmem/sprd-efuse.c | 424 +++++++++++++++++++++++++++++++++++++
 3 files changed, 437 insertions(+)
 create mode 100644 drivers/nvmem/sprd-efuse.c

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index c2ec750cae6e..8fd425d38d97 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -230,4 +230,15 @@ config NVMEM_ZYNQMP
 
 	  If sure, say yes. If unsure, say no.
 
+config SPRD_EFUSE
+	tristate "Spreadtrum SoC eFuse Support"
+	depends on ARCH_SPRD || COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  This is a simple driver to dump specified values of Spreadtrum
+	  SoCs from eFuse.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called nvmem-sprd-efuse.
+
 endif
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index e5c153d99a67..7c19870a6bbe 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile
@@ -50,3 +50,5 @@ obj-$(CONFIG_SC27XX_EFUSE)	+= nvmem-sc27xx-efuse.o
 nvmem-sc27xx-efuse-y		:= sc27xx-efuse.o
 obj-$(CONFIG_NVMEM_ZYNQMP)	+= nvmem_zynqmp_nvmem.o
 nvmem_zynqmp_nvmem-y		:= zynqmp_nvmem.o
+obj-$(CONFIG_SPRD_EFUSE)	+= nvmem_sprd_efuse.o
+nvmem_sprd_efuse-y		:= sprd-efuse.o
diff --git a/drivers/nvmem/sprd-efuse.c b/drivers/nvmem/sprd-efuse.c
new file mode 100644
index 000000000000..2f1e0fbd1901
--- /dev/null
+++ b/drivers/nvmem/sprd-efuse.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2019 Spreadtrum Communications Inc.
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#define SPRD_EFUSE_ENABLE		0x20
+#define SPRD_EFUSE_ERR_FLAG		0x24
+#define SPRD_EFUSE_ERR_CLR		0x28
+#define SPRD_EFUSE_MAGIC_NUM		0x2c
+#define SPRD_EFUSE_FW_CFG		0x50
+#define SPRD_EFUSE_PW_SWT		0x54
+#define SPRD_EFUSE_MEM(val)		(0x1000 + ((val) << 2))
+
+#define SPRD_EFUSE_VDD_EN		BIT(0)
+#define SPRD_EFUSE_AUTO_CHECK_EN	BIT(1)
+#define SPRD_EFUSE_DOUBLE_EN		BIT(2)
+#define SPRD_EFUSE_MARGIN_RD_EN		BIT(3)
+#define SPRD_EFUSE_LOCK_WR_EN		BIT(4)
+
+#define SPRD_EFUSE_ERR_CLR_MASK		GENMASK(13, 0)
+
+#define SPRD_EFUSE_ENK1_ON		BIT(0)
+#define SPRD_EFUSE_ENK2_ON		BIT(1)
+#define SPRD_EFUSE_PROG_EN		BIT(2)
+
+#define SPRD_EFUSE_MAGIC_NUMBER		0x8810
+
+/* Block width (bytes) definitions */
+#define SPRD_EFUSE_BLOCK_WIDTH		4
+
+/*
+ * The Spreadtrum AP efuse contains 2 parts: normal efuse and secure efuse,
+ * and we can only access the normal efuse in kernel. So define the normal
+ * block offset index and normal block numbers.
+ */
+#define SPRD_EFUSE_NORMAL_BLOCK_NUMS	24
+#define SPRD_EFUSE_NORMAL_BLOCK_OFFSET	72
+
+/* Timeout (ms) for the trylock of hardware spinlocks */
+#define SPRD_EFUSE_HWLOCK_TIMEOUT	5000
+
+/*
+ * Since different Spreadtrum SoC chip can have different normal block numbers
+ * and offset. And some SoC can support block double feature, which means
+ * when reading or writing data to efuse memory, the controller can save double
+ * data in case one data become incorrect after a long period.
+ *
+ * Thus we should save them in the device data structure.
+ */
+struct sprd_efuse_variant_data {
+	u32 blk_nums;
+	u32 blk_offset;
+	bool blk_double;
+};
+
+struct sprd_efuse {
+	struct device *dev;
+	struct clk *clk;
+	struct hwspinlock *hwlock;
+	struct mutex mutex;
+	void __iomem *base;
+	const struct sprd_efuse_variant_data *data;
+};
+
+static const struct sprd_efuse_variant_data ums312_data = {
+	.blk_nums = SPRD_EFUSE_NORMAL_BLOCK_NUMS,
+	.blk_offset = SPRD_EFUSE_NORMAL_BLOCK_OFFSET,
+	.blk_double = false,
+};
+
+/*
+ * On Spreadtrum platform, we have multi-subsystems will access the unique
+ * efuse controller, so we need one hardware spinlock to synchronize between
+ * the multiple subsystems.
+ */
+static int sprd_efuse_lock(struct sprd_efuse *efuse)
+{
+	int ret;
+
+	mutex_lock(&efuse->mutex);
+
+	ret = hwspin_lock_timeout_raw(efuse->hwlock,
+				      SPRD_EFUSE_HWLOCK_TIMEOUT);
+	if (ret) {
+		dev_err(efuse->dev, "timeout get the hwspinlock\n");
+		mutex_unlock(&efuse->mutex);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void sprd_efuse_unlock(struct sprd_efuse *efuse)
+{
+	hwspin_unlock_raw(efuse->hwlock);
+	mutex_unlock(&efuse->mutex);
+}
+
+static void sprd_efuse_set_prog_power(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_PW_SWT);
+
+	if (en)
+		val &= ~SPRD_EFUSE_ENK2_ON;
+	else
+		val &= ~SPRD_EFUSE_ENK1_ON;
+
+	writel(val, efuse->base + SPRD_EFUSE_PW_SWT);
+
+	/* Open or close efuse power need wait 1000us to make power stable. */
+	usleep_range(1000, 1200);
+
+	if (en)
+		val |= SPRD_EFUSE_ENK1_ON;
+	else
+		val |= SPRD_EFUSE_ENK2_ON;
+
+	writel(val, efuse->base + SPRD_EFUSE_PW_SWT);
+
+	/* Open or close efuse power need wait 1000us to make power stable. */
+	usleep_range(1000, 1200);
+}
+
+static void sprd_efuse_set_read_power(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_ENABLE);
+
+	if (en)
+		val |= SPRD_EFUSE_VDD_EN;
+	else
+		val &= ~SPRD_EFUSE_VDD_EN;
+
+	writel(val, efuse->base + SPRD_EFUSE_ENABLE);
+
+	/* Open or close efuse power need wait 1000us to make power stable. */
+	usleep_range(1000, 1200);
+}
+
+static void sprd_efuse_set_prog_lock(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_ENABLE);
+
+	if (en)
+		val |= SPRD_EFUSE_LOCK_WR_EN;
+	else
+		val &= ~SPRD_EFUSE_LOCK_WR_EN;
+
+	writel(val, efuse->base + SPRD_EFUSE_ENABLE);
+}
+
+static void sprd_efuse_set_auto_check(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_ENABLE);
+
+	if (en)
+		val |= SPRD_EFUSE_AUTO_CHECK_EN;
+	else
+		val &= ~SPRD_EFUSE_AUTO_CHECK_EN;
+
+	writel(val, efuse->base + SPRD_EFUSE_ENABLE);
+}
+
+static void sprd_efuse_set_data_double(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_ENABLE);
+
+	if (en)
+		val |= SPRD_EFUSE_DOUBLE_EN;
+	else
+		val &= ~SPRD_EFUSE_DOUBLE_EN;
+
+	writel(val, efuse->base + SPRD_EFUSE_ENABLE);
+}
+
+static void sprd_efuse_set_prog_en(struct sprd_efuse *efuse, bool en)
+{
+	u32 val = readl(efuse->base + SPRD_EFUSE_PW_SWT);
+
+	if (en)
+		val |= SPRD_EFUSE_PROG_EN;
+	else
+		val &= ~SPRD_EFUSE_PROG_EN;
+
+	writel(val, efuse->base + SPRD_EFUSE_PW_SWT);
+}
+
+static int sprd_efuse_raw_prog(struct sprd_efuse *efuse, u32 blk, bool doub,
+			       bool lock, u32 *data)
+{
+	u32 status;
+	int ret = 0;
+
+	/*
+	 * We need set the correct magic number before writing the efuse to
+	 * allow programming, and block other programming until we clear the
+	 * magic number.
+	 */
+	writel(SPRD_EFUSE_MAGIC_NUMBER,
+	       efuse->base + SPRD_EFUSE_MAGIC_NUM);
+
+	/*
+	 * Power on the efuse, enable programme and enable double data
+	 * if asked.
+	 */
+	sprd_efuse_set_prog_power(efuse, true);
+	sprd_efuse_set_prog_en(efuse, true);
+	sprd_efuse_set_data_double(efuse, doub);
+
+	/*
+	 * Enable the auto-check function to validate if the programming is
+	 * successful.
+	 */
+	sprd_efuse_set_auto_check(efuse, true);
+
+	writel(*data, efuse->base + SPRD_EFUSE_MEM(blk));
+
+	/* Disable auto-check and data double after programming */
+	sprd_efuse_set_auto_check(efuse, false);
+	sprd_efuse_set_data_double(efuse, false);
+
+	/*
+	 * Check the efuse error status, if the programming is successful,
+	 * we should lock this efuse block to avoid programming again.
+	 */
+	status = readl(efuse->base + SPRD_EFUSE_ERR_FLAG);
+	if (status) {
+		dev_err(efuse->dev,
+			"write error status %d of block %d\n", ret, blk);
+
+		writel(SPRD_EFUSE_ERR_CLR_MASK,
+		       efuse->base + SPRD_EFUSE_ERR_CLR);
+		ret = -EBUSY;
+	} else {
+		sprd_efuse_set_prog_lock(efuse, lock);
+		writel(*data, efuse->base + SPRD_EFUSE_MEM(blk));
+		sprd_efuse_set_prog_lock(efuse, false);
+	}
+
+	sprd_efuse_set_prog_power(efuse, false);
+	writel(0, efuse->base + SPRD_EFUSE_MAGIC_NUM);
+
+	return ret;
+}
+
+static int sprd_efuse_raw_read(struct sprd_efuse *efuse, int blk, u32 *val,
+			       bool doub)
+{
+	u32 status;
+
+	/*
+	 * Need power on the efuse before reading data from efuse, and will
+	 * power off the efuse after reading process.
+	 */
+	sprd_efuse_set_read_power(efuse, true);
+
+	/* Enable double data if asked */
+	sprd_efuse_set_data_double(efuse, doub);
+
+	/* Start to read data from efuse block */
+	*val = readl(efuse->base + SPRD_EFUSE_MEM(blk));
+
+	/* Disable double data */
+	sprd_efuse_set_data_double(efuse, false);
+
+	/* Power off the efuse */
+	sprd_efuse_set_read_power(efuse, false);
+
+	/*
+	 * Check the efuse error status and clear them if there are some
+	 * errors occurred.
+	 */
+	status = readl(efuse->base + SPRD_EFUSE_ERR_FLAG);
+	if (status) {
+		dev_err(efuse->dev,
+			"read error status %d of block %d\n", status, blk);
+
+		writel(SPRD_EFUSE_ERR_CLR_MASK,
+		       efuse->base + SPRD_EFUSE_ERR_CLR);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int sprd_efuse_read(void *context, u32 offset, void *val, size_t bytes)
+{
+	struct sprd_efuse *efuse = context;
+	bool blk_double = efuse->data->blk_double;
+	u32 index = offset / SPRD_EFUSE_BLOCK_WIDTH + efuse->data->blk_offset;
+	u32 blk_offset = (offset % SPRD_EFUSE_BLOCK_WIDTH) * BITS_PER_BYTE;
+	u32 data;
+	int ret;
+
+	ret = sprd_efuse_lock(efuse);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(efuse->clk);
+	if (ret)
+		goto unlock;
+
+	ret = sprd_efuse_raw_read(efuse, index, &data, blk_double);
+	if (!ret) {
+		data >>= blk_offset;
+		memcpy(val, &data, bytes);
+	}
+
+	clk_disable_unprepare(efuse->clk);
+
+unlock:
+	sprd_efuse_unlock(efuse);
+	return ret;
+}
+
+static int sprd_efuse_write(void *context, u32 offset, void *val, size_t bytes)
+{
+	struct sprd_efuse *efuse = context;
+	int ret;
+
+	ret = sprd_efuse_lock(efuse);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(efuse->clk);
+	if (ret)
+		goto unlock;
+
+	ret = sprd_efuse_raw_prog(efuse, offset, false, false, val);
+
+	clk_disable_unprepare(efuse->clk);
+
+unlock:
+	sprd_efuse_unlock(efuse);
+	return ret;
+}
+
+static int sprd_efuse_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct nvmem_device *nvmem;
+	struct nvmem_config econfig = { };
+	struct sprd_efuse *efuse;
+	const struct sprd_efuse_variant_data *pdata;
+	int ret;
+
+	pdata = of_device_get_match_data(&pdev->dev);
+	if (!pdata) {
+		dev_err(&pdev->dev, "No matching driver data found\n");
+		return -EINVAL;
+	}
+
+	efuse = devm_kzalloc(&pdev->dev, sizeof(*efuse), GFP_KERNEL);
+	if (!efuse)
+		return -ENOMEM;
+
+	efuse->base = devm_platform_ioremap_resource(pdev, 0);
+	if (!efuse->base)
+		return -ENOMEM;
+
+	ret = of_hwspin_lock_get_id(np, 0);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to get hwlock id\n");
+		return ret;
+	}
+
+	efuse->hwlock = devm_hwspin_lock_request_specific(&pdev->dev, ret);
+	if (!efuse->hwlock) {
+		dev_err(&pdev->dev, "failed to request hwlock\n");
+		return -ENXIO;
+	}
+
+	efuse->clk = devm_clk_get(&pdev->dev, "enable");
+	if (IS_ERR(efuse->clk)) {
+		dev_err(&pdev->dev, "failed to get enable clock\n");
+		return PTR_ERR(efuse->clk);
+	}
+
+	mutex_init(&efuse->mutex);
+	efuse->dev = &pdev->dev;
+	efuse->data = pdata;
+
+	econfig.stride = 1;
+	econfig.word_size = 1;
+	econfig.read_only = false;
+	econfig.name = "sprd-efuse";
+	econfig.size = efuse->data->blk_nums * SPRD_EFUSE_BLOCK_WIDTH;
+	econfig.reg_read = sprd_efuse_read;
+	econfig.reg_write = sprd_efuse_write;
+	econfig.priv = efuse;
+	econfig.dev = &pdev->dev;
+	nvmem = devm_nvmem_register(&pdev->dev, &econfig);
+	if (IS_ERR(nvmem)) {
+		dev_err(&pdev->dev, "failed to register nvmem\n");
+		return PTR_ERR(nvmem);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id sprd_efuse_of_match[] = {
+	{ .compatible = "sprd,ums312-efuse", .data = &ums312_data },
+	{ }
+};
+
+static struct platform_driver sprd_efuse_driver = {
+	.probe = sprd_efuse_probe,
+	.driver = {
+		.name = "sprd-efuse",
+		.of_match_table = sprd_efuse_of_match,
+	},
+};
+
+module_platform_driver(sprd_efuse_driver);
+
+MODULE_AUTHOR("Freeman Liu <freeman.liu@spreadtrum.com>");
+MODULE_DESCRIPTION("Spreadtrum AP efuse driver");
+MODULE_LICENSE("GPL v2");
-- 
2.21.0

[PATCH 08/10] nvmem: imx: scu: fix dependency in Kconfig

[Srinivas Kandagatla]

Fix below error by adding HAVE_ARM_SMCCC dependency in Kconfig
ERROR: "__arm_smccc_smc" [drivers/nvmem/nvmem-imx-ocotp-scu.ko] undefined!

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 8fd425d38d97..fd0716818881 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -50,6 +50,7 @@ config NVMEM_IMX_OCOTP
 config NVMEM_IMX_OCOTP_SCU
 	tristate "i.MX8 SCU On-Chip OTP Controller support"
 	depends on IMX_SCU
+	depends on HAVE_ARM_SMCCC
 	help
 	  This is a driver for the SCU On-Chip OTP Controller (OCOTP)
 	  available on i.MX8 SoCs.
-- 
2.21.0

[PATCH 09/10] dt-bindings: nvmem: add binding for Rockchip OTP controller

[Srinivas Kandagatla]

From: Heiko Stuebner <heiko@sntech.de>

Newer Rockchip SoCs use a different IP for accessing special one-
time-programmable memory, so add a binding for these controllers.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 .../bindings/nvmem/rockchip-otp.txt           | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/rockchip-otp.txt

diff --git a/Documentation/devicetree/bindings/nvmem/rockchip-otp.txt b/Documentation/devicetree/bindings/nvmem/rockchip-otp.txt
new file mode 100644
index 000000000000..40f649f7c2e5
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/rockchip-otp.txt
@@ -0,0 +1,25 @@
+Rockchip internal OTP (One Time Programmable) memory device tree bindings
+
+Required properties:
+- compatible: Should be one of the following.
+  - "rockchip,px30-otp" - for PX30 SoCs.
+  - "rockchip,rk3308-otp" - for RK3308 SoCs.
+- reg: Should contain the registers location and size
+- clocks: Must contain an entry for each entry in clock-names.
+- clock-names: Should be "otp", "apb_pclk" and "phy".
+- resets: Must contain an entry for each entry in reset-names.
+  See ../../reset/reset.txt for details.
+- reset-names: Should be "phy".
+
+See nvmem.txt for more information.
+
+Example:
+	otp: otp@ff290000 {
+		compatible = "rockchip,px30-otp";
+		reg = <0x0 0xff290000 0x0 0x4000>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		clocks = <&cru SCLK_OTP_USR>, <&cru PCLK_OTP_NS>,
+			 <&cru PCLK_OTP_PHY>;
+		clock-names = "otp", "apb_pclk", "phy";
+	};
-- 
2.21.0

[PATCH 10/10] nvmem: add Rockchip OTP driver

[Srinivas Kandagatla]

From: Finley Xiao <finley.xiao@rock-chips.com>

Newer Rockchip socs like the px30 use a different one-time-programmable
memory controller for things like cpu-id and leakage information,
so add the necessary driver for it.

Signed-off-by: Finley Xiao <finley.xiao@rock-chips.com>
[ported from vendor 4.4, converted to clock-bulk API and cleanups]
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/nvmem/Kconfig        |  11 ++
 drivers/nvmem/Makefile       |   2 +
 drivers/nvmem/rockchip-otp.c | 268 +++++++++++++++++++++++++++++++++++
 3 files changed, 281 insertions(+)
 create mode 100644 drivers/nvmem/rockchip-otp.c

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index fd0716818881..73567e922491 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -120,6 +120,17 @@ config ROCKCHIP_EFUSE
 	  This driver can also be built as a module. If so, the module
 	  will be called nvmem_rockchip_efuse.
 
+config ROCKCHIP_OTP
+	tristate "Rockchip OTP controller support"
+	depends on ARCH_ROCKCHIP || COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  This is a simple drive to dump specified values of Rockchip SoC
+	  from otp, such as cpu-leakage.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called nvmem_rockchip_otp.
+
 config NVMEM_BCM_OCOTP
 	tristate "Broadcom On-Chip OTP Controller support"
 	depends on ARCH_BCM_IPROC || COMPILE_TEST
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index 7c19870a6bbe..9e667823edb3 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile
@@ -30,6 +30,8 @@ obj-$(CONFIG_QCOM_QFPROM)	+= nvmem_qfprom.o
 nvmem_qfprom-y			:= qfprom.o
 obj-$(CONFIG_ROCKCHIP_EFUSE)	+= nvmem_rockchip_efuse.o
 nvmem_rockchip_efuse-y		:= rockchip-efuse.o
+obj-$(CONFIG_ROCKCHIP_OTP)	+= nvmem-rockchip-otp.o
+nvmem-rockchip-otp-y		:= rockchip-otp.o
 obj-$(CONFIG_NVMEM_SUNXI_SID)	+= nvmem_sunxi_sid.o
 nvmem_stm32_romem-y 		:= stm32-romem.o
 obj-$(CONFIG_NVMEM_STM32_ROMEM) += nvmem_stm32_romem.o
diff --git a/drivers/nvmem/rockchip-otp.c b/drivers/nvmem/rockchip-otp.c
new file mode 100644
index 000000000000..9f53bcce2f87
--- /dev/null
+++ b/drivers/nvmem/rockchip-otp.c
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Rockchip OTP Driver
+ *
+ * Copyright (c) 2018 Rockchip Electronics Co. Ltd.
+ * Author: Finley Xiao <finley.xiao@rock-chips.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+/* OTP Register Offsets */
+#define OTPC_SBPI_CTRL			0x0020
+#define OTPC_SBPI_CMD_VALID_PRE		0x0024
+#define OTPC_SBPI_CS_VALID_PRE		0x0028
+#define OTPC_SBPI_STATUS		0x002C
+#define OTPC_USER_CTRL			0x0100
+#define OTPC_USER_ADDR			0x0104
+#define OTPC_USER_ENABLE		0x0108
+#define OTPC_USER_Q			0x0124
+#define OTPC_INT_STATUS			0x0304
+#define OTPC_SBPI_CMD0_OFFSET		0x1000
+#define OTPC_SBPI_CMD1_OFFSET		0x1004
+
+/* OTP Register bits and masks */
+#define OTPC_USER_ADDR_MASK		GENMASK(31, 16)
+#define OTPC_USE_USER			BIT(0)
+#define OTPC_USE_USER_MASK		GENMASK(16, 16)
+#define OTPC_USER_FSM_ENABLE		BIT(0)
+#define OTPC_USER_FSM_ENABLE_MASK	GENMASK(16, 16)
+#define OTPC_SBPI_DONE			BIT(1)
+#define OTPC_USER_DONE			BIT(2)
+
+#define SBPI_DAP_ADDR			0x02
+#define SBPI_DAP_ADDR_SHIFT		8
+#define SBPI_DAP_ADDR_MASK		GENMASK(31, 24)
+#define SBPI_CMD_VALID_MASK		GENMASK(31, 16)
+#define SBPI_DAP_CMD_WRF		0xC0
+#define SBPI_DAP_REG_ECC		0x3A
+#define SBPI_ECC_ENABLE			0x00
+#define SBPI_ECC_DISABLE		0x09
+#define SBPI_ENABLE			BIT(0)
+#define SBPI_ENABLE_MASK		GENMASK(16, 16)
+
+#define OTPC_TIMEOUT			10000
+
+struct rockchip_otp {
+	struct device *dev;
+	void __iomem *base;
+	struct clk_bulk_data	*clks;
+	int num_clks;
+	struct reset_control *rst;
+};
+
+/* list of required clocks */
+static const char * const rockchip_otp_clocks[] = {
+	"otp", "apb_pclk", "phy",
+};
+
+struct rockchip_data {
+	int size;
+};
+
+static int rockchip_otp_reset(struct rockchip_otp *otp)
+{
+	int ret;
+
+	ret = reset_control_assert(otp->rst);
+	if (ret) {
+		dev_err(otp->dev, "failed to assert otp phy %d\n", ret);
+		return ret;
+	}
+
+	udelay(2);
+
+	ret = reset_control_deassert(otp->rst);
+	if (ret) {
+		dev_err(otp->dev, "failed to deassert otp phy %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rockchip_otp_wait_status(struct rockchip_otp *otp, u32 flag)
+{
+	u32 status = 0;
+	int ret;
+
+	ret = readl_poll_timeout_atomic(otp->base + OTPC_INT_STATUS, status,
+					(status & flag), 1, OTPC_TIMEOUT);
+	if (ret)
+		return ret;
+
+	/* clean int status */
+	writel(flag, otp->base + OTPC_INT_STATUS);
+
+	return 0;
+}
+
+static int rockchip_otp_ecc_enable(struct rockchip_otp *otp, bool enable)
+{
+	int ret = 0;
+
+	writel(SBPI_DAP_ADDR_MASK | (SBPI_DAP_ADDR << SBPI_DAP_ADDR_SHIFT),
+	       otp->base + OTPC_SBPI_CTRL);
+
+	writel(SBPI_CMD_VALID_MASK | 0x1, otp->base + OTPC_SBPI_CMD_VALID_PRE);
+	writel(SBPI_DAP_CMD_WRF | SBPI_DAP_REG_ECC,
+	       otp->base + OTPC_SBPI_CMD0_OFFSET);
+	if (enable)
+		writel(SBPI_ECC_ENABLE, otp->base + OTPC_SBPI_CMD1_OFFSET);
+	else
+		writel(SBPI_ECC_DISABLE, otp->base + OTPC_SBPI_CMD1_OFFSET);
+
+	writel(SBPI_ENABLE_MASK | SBPI_ENABLE, otp->base + OTPC_SBPI_CTRL);
+
+	ret = rockchip_otp_wait_status(otp, OTPC_SBPI_DONE);
+	if (ret < 0)
+		dev_err(otp->dev, "timeout during ecc_enable\n");
+
+	return ret;
+}
+
+static int rockchip_otp_read(void *context, unsigned int offset,
+			     void *val, size_t bytes)
+{
+	struct rockchip_otp *otp = context;
+	u8 *buf = val;
+	int ret = 0;
+
+	ret = clk_bulk_prepare_enable(otp->num_clks, otp->clks);
+	if (ret < 0) {
+		dev_err(otp->dev, "failed to prepare/enable clks\n");
+		return ret;
+	}
+
+	ret = rockchip_otp_reset(otp);
+	if (ret) {
+		dev_err(otp->dev, "failed to reset otp phy\n");
+		goto disable_clks;
+	}
+
+	ret = rockchip_otp_ecc_enable(otp, false);
+	if (ret < 0) {
+		dev_err(otp->dev, "rockchip_otp_ecc_enable err\n");
+		goto disable_clks;
+	}
+
+	writel(OTPC_USE_USER | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL);
+	udelay(5);
+	while (bytes--) {
+		writel(offset++ | OTPC_USER_ADDR_MASK,
+		       otp->base + OTPC_USER_ADDR);
+		writel(OTPC_USER_FSM_ENABLE | OTPC_USER_FSM_ENABLE_MASK,
+		       otp->base + OTPC_USER_ENABLE);
+		ret = rockchip_otp_wait_status(otp, OTPC_USER_DONE);
+		if (ret < 0) {
+			dev_err(otp->dev, "timeout during read setup\n");
+			goto read_end;
+		}
+		*buf++ = readb(otp->base + OTPC_USER_Q);
+	}
+
+read_end:
+	writel(0x0 | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL);
+disable_clks:
+	clk_bulk_disable_unprepare(otp->num_clks, otp->clks);
+
+	return ret;
+}
+
+static struct nvmem_config otp_config = {
+	.name = "rockchip-otp",
+	.owner = THIS_MODULE,
+	.read_only = true,
+	.stride = 1,
+	.word_size = 1,
+	.reg_read = rockchip_otp_read,
+};
+
+static const struct rockchip_data px30_data = {
+	.size = 0x40,
+};
+
+static const struct of_device_id rockchip_otp_match[] = {
+	{
+		.compatible = "rockchip,px30-otp",
+		.data = (void *)&px30_data,
+	},
+	{
+		.compatible = "rockchip,rk3308-otp",
+		.data = (void *)&px30_data,
+	},
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, rockchip_otp_match);
+
+static int rockchip_otp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rockchip_otp *otp;
+	const struct rockchip_data *data;
+	struct nvmem_device *nvmem;
+	int ret, i;
+
+	data = of_device_get_match_data(dev);
+	if (!data) {
+		dev_err(dev, "failed to get match data\n");
+		return -EINVAL;
+	}
+
+	otp = devm_kzalloc(&pdev->dev, sizeof(struct rockchip_otp),
+			   GFP_KERNEL);
+	if (!otp)
+		return -ENOMEM;
+
+	otp->dev = dev;
+	otp->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(otp->base))
+		return PTR_ERR(otp->base);
+
+	otp->num_clks = ARRAY_SIZE(rockchip_otp_clocks);
+	otp->clks = devm_kcalloc(dev, otp->num_clks,
+				     sizeof(*otp->clks), GFP_KERNEL);
+	if (!otp->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < otp->num_clks; ++i)
+		otp->clks[i].id = rockchip_otp_clocks[i];
+
+	ret = devm_clk_bulk_get(dev, otp->num_clks, otp->clks);
+	if (ret)
+		return ret;
+
+	otp->rst = devm_reset_control_get(dev, "phy");
+	if (IS_ERR(otp->rst))
+		return PTR_ERR(otp->rst);
+
+	otp_config.size = data->size;
+	otp_config.priv = otp;
+	otp_config.dev = dev;
+	nvmem = devm_nvmem_register(dev, &otp_config);
+
+	return PTR_ERR_OR_ZERO(nvmem);
+}
+
+static struct platform_driver rockchip_otp_driver = {
+	.probe = rockchip_otp_probe,
+	.driver = {
+		.name = "rockchip-otp",
+		.of_match_table = rockchip_otp_match,
+	},
+};
+
+module_platform_driver(rockchip_otp_driver);
+MODULE_DESCRIPTION("Rockchip OTP driver");
+MODULE_LICENSE("GPL v2");
-- 
2.21.0