Merge tag 'char-misc-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc and other driver patches for 5.5-rc1

  Loads of different things in here, this feels like the catch-all of
  driver subsystems these days. Full details are in the shortlog, but
  nothing major overall, just lots of driver updates and additions.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (198 commits)
  char: Fix Kconfig indentation, continued
  habanalabs: add more protection of device during reset
  habanalabs: flush EQ workers in hard reset
  habanalabs: make the reset code more consistent
  habanalabs: expose reset counters via existing INFO IOCTL
  habanalabs: make code more concise
  habanalabs: use defines for F/W files
  habanalabs: remove prints on successful device initialization
  habanalabs: remove unnecessary checks
  habanalabs: invalidate MMU cache only once
  habanalabs: skip VA block list update in reset flow
  habanalabs: optimize MMU unmap
  habanalabs: prevent read/write from/to the device during hard reset
  habanalabs: split MMU properties to PCI/DRAM
  habanalabs: re-factor MMU masks and documentation
  habanalabs: type specific MMU cache invalidation
  habanalabs: re-factor memory module code
  habanalabs: export uapi defines to user-space
  habanalabs: don't print error when queues are full
  habanalabs: increase max jobs number to 512
  ...

7 files changed, 838 insertions, 18 deletions

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index c2ec750cae6e..73567e922491 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.
@@ -119,6 +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
@@ -230,4 +242,15 @@ 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..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-$(CONFIG_NVMEM_STM32_ROMEM) += nvmem_stm32_romem.o
@@ -50,3 +52,5 @@ obj-$(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/imx-ocotp-scu.c b/drivers/nvmem/imx-ocotp-scu.c
index 61a17f943f47..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>
@@ -14,14 +15,28 @@
 #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,
 };
 
+#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 {
@@ -35,16 +50,63 @@ 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,
+	.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 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)
 {
@@ -88,18 +150,19 @@ 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++) {
-		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);
 		if (ret) {
+			mutex_unlock(&scu_ocotp_mutex);
 			kfree(p);
 			return ret;
 		}
@@ -108,18 +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[] = {
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;
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");
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,
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");