[PATCH v1 1/1] nvmem: Change return type of reg read/write to ssize_t

From: Joy Chakraborty
Date: Mon Feb 19 2024 - 06:32:55 EST


Change return type of reg_read() and reg_write() callback to ssize_t for
nvmem suppliers to return number of bytes read/written to the nvmem core.

Currently nvmem core assumes the amount of data read/written is equal
to what it has requested from the supplier, this return code facilitates
better error handling in the nvmem core.

Signed-off-by: Joy Chakraborty <joychakr@xxxxxxxxxx>
---
drivers/nvmem/apple-efuses.c | 5 +-
drivers/nvmem/bcm-ocotp.c | 8 ++--
drivers/nvmem/brcm_nvram.c | 8 +++-
drivers/nvmem/core.c | 73 +++++++++++++----------------
drivers/nvmem/imx-iim.c | 4 +-
drivers/nvmem/imx-ocotp-ele.c | 4 +-
drivers/nvmem/imx-ocotp-scu.c | 8 ++--
drivers/nvmem/imx-ocotp.c | 6 +--
drivers/nvmem/jz4780-efuse.c | 5 +-
drivers/nvmem/lan9662-otpc.c | 8 ++--
drivers/nvmem/layerscape-sfp.c | 7 ++-
drivers/nvmem/lpc18xx_eeprom.c | 10 ++--
drivers/nvmem/lpc18xx_otp.c | 4 +-
drivers/nvmem/meson-efuse.c | 10 +++-
drivers/nvmem/meson-mx-efuse.c | 4 +-
drivers/nvmem/microchip-otpc.c | 4 +-
drivers/nvmem/mtk-efuse.c | 4 +-
drivers/nvmem/mxs-ocotp.c | 5 +-
drivers/nvmem/nintendo-otp.c | 4 +-
drivers/nvmem/qcom-spmi-sdam.c | 8 ++--
drivers/nvmem/qfprom.c | 10 ++--
drivers/nvmem/qoriq-efuse.c | 4 +-
drivers/nvmem/rave-sp-eeprom.c | 12 ++---
drivers/nvmem/rmem.c | 2 +-
drivers/nvmem/rockchip-efuse.c | 11 +++--
drivers/nvmem/rockchip-otp.c | 13 ++---
drivers/nvmem/sc27xx-efuse.c | 3 +-
drivers/nvmem/sec-qfprom.c | 4 +-
drivers/nvmem/snvs_lpgpr.c | 13 +++--
drivers/nvmem/sprd-efuse.c | 8 ++--
drivers/nvmem/stm32-bsec-optee-ta.c | 8 ++--
drivers/nvmem/stm32-bsec-optee-ta.h | 12 ++---
drivers/nvmem/stm32-romem.c | 16 +++----
drivers/nvmem/sunplus-ocotp.c | 4 +-
drivers/nvmem/sunxi_sid.c | 11 +++--
drivers/nvmem/u-boot-env.c | 4 +-
drivers/nvmem/uniphier-efuse.c | 4 +-
drivers/nvmem/vf610-ocotp.c | 5 +-
drivers/nvmem/zynqmp_nvmem.c | 2 +-
include/linux/nvmem-provider.h | 4 +-
40 files changed, 180 insertions(+), 159 deletions(-)

diff --git a/drivers/nvmem/apple-efuses.c b/drivers/nvmem/apple-efuses.c
index d3d49d22338b..9a564cb0f26d 100644
--- a/drivers/nvmem/apple-efuses.c
+++ b/drivers/nvmem/apple-efuses.c
@@ -15,10 +15,11 @@ struct apple_efuses_priv {
void __iomem *fuses;
};

-static int apple_efuses_read(void *context, unsigned int offset, void *val,
+static ssize_t apple_efuses_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct apple_efuses_priv *priv = context;
+ size_t bytes_read = bytes;
u32 *dst = val;

while (bytes >= sizeof(u32)) {
@@ -27,7 +28,7 @@ static int apple_efuses_read(void *context, unsigned int offset, void *val,
offset += sizeof(u32);
}

- return 0;
+ return bytes_read;
}

static int apple_efuses_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/bcm-ocotp.c b/drivers/nvmem/bcm-ocotp.c
index 2490f44caa40..803354574fe0 100644
--- a/drivers/nvmem/bcm-ocotp.c
+++ b/drivers/nvmem/bcm-ocotp.c
@@ -148,7 +148,7 @@ static int disable_ocotp_program(void __iomem *base)
return ret;
}

-static int bcm_otpc_read(void *context, unsigned int offset, void *val,
+static ssize_t bcm_otpc_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct otpc_priv *priv = context;
@@ -176,10 +176,10 @@ static int bcm_otpc_read(void *context, unsigned int offset, void *val,
reset_start_bit(priv->base);
}

- return 0;
+ return bytes_read;
}

-static int bcm_otpc_write(void *context, unsigned int offset, void *val,
+static ssize_t bcm_otpc_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct otpc_priv *priv = context;
@@ -214,7 +214,7 @@ static int bcm_otpc_write(void *context, unsigned int offset, void *val,

disable_ocotp_program(priv->base);

- return 0;
+ return bytes_written;
}

static struct nvmem_config bcm_otpc_nvmem_config = {
diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c
index 5cdf339cfbec..d8700b7e2642 100644
--- a/drivers/nvmem/brcm_nvram.c
+++ b/drivers/nvmem/brcm_nvram.c
@@ -46,7 +46,7 @@ struct brcm_nvram_header {
__le32 config_ncdl; /* ncdl values for memc */
};

-static int brcm_nvram_read(void *context, unsigned int offset, void *val,
+static ssize_t brcm_nvram_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct brcm_nvram *priv = context;
@@ -61,7 +61,11 @@ static int brcm_nvram_read(void *context, unsigned int offset, void *val,

memset((uint8_t *)val + to_copy, priv->padding_byte, bytes - to_copy);

- return 0;
+ /*
+ * Returning bytes requested as the whole buffer is padded even if the
+ * requested bytes to be read is out of bounds of resource size.
+ */
+ return bytes;
}

static int brcm_nvram_copy_data(struct brcm_nvram *priv, struct platform_device *pdev)
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index eb357ac2e54a..c3ee526d9396 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -55,7 +55,7 @@ static LIST_HEAD(nvmem_lookup_list);

static BLOCKING_NOTIFIER_HEAD(nvmem_notifier);

-static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
+static ssize_t __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (nvmem->reg_read)
@@ -64,10 +64,10 @@ static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
return -EINVAL;
}

-static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
+static ssize_t __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
- int ret;
+ ssize_t ret;

if (nvmem->reg_write) {
gpiod_set_value_cansleep(nvmem->wp_gpio, 0);
@@ -79,7 +79,7 @@ static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
return -EINVAL;
}

-static int nvmem_access_with_keepouts(struct nvmem_device *nvmem,
+static ssize_t nvmem_access_with_keepouts(struct nvmem_device *nvmem,
unsigned int offset, void *val,
size_t bytes, int write)
{
@@ -88,7 +88,7 @@ static int nvmem_access_with_keepouts(struct nvmem_device *nvmem,
unsigned int kend, ksize;
const struct nvmem_keepout *keepout = nvmem->keepout;
const struct nvmem_keepout *keepoutend = keepout + nvmem->nkeepout;
- int rc;
+ ssize_t rc, count = 0;

/*
* Skip all keepouts before the range being accessed.
@@ -107,11 +107,12 @@ static int nvmem_access_with_keepouts(struct nvmem_device *nvmem,
else
rc = __nvmem_reg_read(nvmem, offset, val, ksize);

- if (rc)
+ if (rc < 0)
return rc;

offset += ksize;
val += ksize;
+ count += rc;
}

/*
@@ -135,15 +136,20 @@ static int nvmem_access_with_keepouts(struct nvmem_device *nvmem,
if (offset < end) {
ksize = end - offset;
if (write)
- return __nvmem_reg_write(nvmem, offset, val, ksize);
+ rc = __nvmem_reg_write(nvmem, offset, val, ksize);
else
- return __nvmem_reg_read(nvmem, offset, val, ksize);
+ rc = __nvmem_reg_read(nvmem, offset, val, ksize);
+
+ if (rc < 0)
+ return rc;
+
+ count += rc;
}

- return 0;
+ return count;
}

-static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
+static ssize_t nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (!nvmem->nkeepout)
@@ -152,7 +158,7 @@ static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
return nvmem_access_with_keepouts(nvmem, offset, val, bytes, false);
}

-static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
+static ssize_t nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (!nvmem->nkeepout)
@@ -195,7 +201,6 @@ static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
{
struct device *dev;
struct nvmem_device *nvmem;
- int rc;

if (attr->private)
dev = attr->private;
@@ -221,12 +226,7 @@ static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
if (!nvmem->reg_read)
return -EPERM;

- rc = nvmem_reg_read(nvmem, pos, buf, count);
-
- if (rc)
- return rc;
-
- return count;
+ return nvmem_reg_read(nvmem, pos, buf, count);
}

static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
@@ -235,7 +235,6 @@ static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
{
struct device *dev;
struct nvmem_device *nvmem;
- int rc;

if (attr->private)
dev = attr->private;
@@ -261,12 +260,7 @@ static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
if (!nvmem->reg_write)
return -EPERM;

- rc = nvmem_reg_write(nvmem, pos, buf, count);
-
- if (rc)
- return rc;
-
- return count;
+ return nvmem_reg_write(nvmem, pos, buf, count);
}

static umode_t nvmem_bin_attr_get_umode(struct nvmem_device *nvmem)
@@ -1633,9 +1627,12 @@ static int __nvmem_cell_read(struct nvmem_device *nvmem,

rc = nvmem_reg_read(nvmem, cell->offset, buf, cell->raw_len);

- if (rc)
+ if (rc < 0)
return rc;

+ if (rc != cell->raw_len)
+ return -EIO;
+
/* shift bits in-place */
if (cell->bit_offset || cell->nbits)
nvmem_shift_read_buffer_in_place(cell, buf);
@@ -1708,8 +1705,11 @@ static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell_entry *cell,

/* setup the first byte with lsb bits from nvmem */
rc = nvmem_reg_read(nvmem, cell->offset, &v, 1);
- if (rc)
+ if (rc < 1) {
+ if (rc == 0)
+ rc = -EIO;
goto err;
+ }
*b++ |= GENMASK(bit_offset - 1, 0) & v;

/* setup rest of the byte if any */
@@ -1728,8 +1728,11 @@ static void *nvmem_cell_prepare_write_buffer(struct nvmem_cell_entry *cell,
/* setup the last byte with msb bits from nvmem */
rc = nvmem_reg_read(nvmem,
cell->offset + cell->bytes - 1, &v, 1);
- if (rc)
+ if (rc < 1) {
+ if (rc == 0)
+ rc = -EIO;
goto err;
+ }
*p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v;

}
@@ -1769,10 +1772,7 @@ static int __nvmem_cell_entry_write(struct nvmem_cell_entry *cell, void *buf, si
if (cell->bit_offset || cell->nbits)
kfree(buf);

- if (rc)
- return rc;
-
- return len;
+ return rc;
}

/**
@@ -2047,17 +2047,10 @@ int nvmem_device_read(struct nvmem_device *nvmem,
unsigned int offset,
size_t bytes, void *buf)
{
- int rc;
-
if (!nvmem)
return -EINVAL;

- rc = nvmem_reg_read(nvmem, offset, buf, bytes);
-
- if (rc)
- return rc;
-
- return bytes;
+ return nvmem_reg_read(nvmem, offset, buf, bytes);
}
EXPORT_SYMBOL_GPL(nvmem_device_read);

diff --git a/drivers/nvmem/imx-iim.c b/drivers/nvmem/imx-iim.c
index f13bbd164086..af46c5490416 100644
--- a/drivers/nvmem/imx-iim.c
+++ b/drivers/nvmem/imx-iim.c
@@ -29,7 +29,7 @@ struct iim_priv {
struct clk *clk;
};

-static int imx_iim_read(void *context, unsigned int offset,
+static ssize_t imx_iim_read(void *context, unsigned int offset,
void *buf, size_t bytes)
{
struct iim_priv *iim = context;
@@ -49,7 +49,7 @@ static int imx_iim_read(void *context, unsigned int offset,

clk_disable_unprepare(iim->clk);

- return 0;
+ return bytes;
}

static struct imx_iim_drvdata imx27_drvdata = {
diff --git a/drivers/nvmem/imx-ocotp-ele.c b/drivers/nvmem/imx-ocotp-ele.c
index cf920542f939..3025fe8aa991 100644
--- a/drivers/nvmem/imx-ocotp-ele.c
+++ b/drivers/nvmem/imx-ocotp-ele.c
@@ -61,7 +61,7 @@ static enum fuse_type imx_ocotp_fuse_type(void *context, u32 index)
return FUSE_INVALID;
}

-static int imx_ocotp_reg_read(void *context, unsigned int offset, void *val, size_t bytes)
+static ssize_t imx_ocotp_reg_read(void *context, unsigned int offset, void *val, size_t bytes)
{
struct imx_ocotp_priv *priv = context;
void __iomem *reg = priv->base + priv->data->reg_off;
@@ -102,7 +102,7 @@ static int imx_ocotp_reg_read(void *context, unsigned int offset, void *val, siz

kfree(p);

- return 0;
+ return bytes;
};

static int imx_ele_ocotp_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/imx-ocotp-scu.c b/drivers/nvmem/imx-ocotp-scu.c
index 517d83e11af2..2f9b9f035c49 100644
--- a/drivers/nvmem/imx-ocotp-scu.c
+++ b/drivers/nvmem/imx-ocotp-scu.c
@@ -129,7 +129,7 @@ static int imx_sc_misc_otp_fuse_read(struct imx_sc_ipc *ipc, u32 word,
return 0;
}

-static int imx_scu_ocotp_read(void *context, unsigned int offset,
+static ssize_t imx_scu_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
@@ -174,10 +174,10 @@ static int imx_scu_ocotp_read(void *context, unsigned int offset,

kfree(p);

- return 0;
+ return bytes;
}

-static int imx_scu_ocotp_write(void *context, unsigned int offset,
+static ssize_t imx_scu_ocotp_write(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
@@ -215,7 +215,7 @@ static int imx_scu_ocotp_write(void *context, unsigned int offset,

mutex_unlock(&scu_ocotp_mutex);

- return res.a0;
+ return res.a0 < 0 ? res.a0 : bytes;
}

static struct nvmem_config imx_scu_ocotp_nvmem_config = {
diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index 79dd4fda0329..2b04d49c7bf0 100644
--- a/drivers/nvmem/imx-ocotp.c
+++ b/drivers/nvmem/imx-ocotp.c
@@ -154,7 +154,7 @@ static void imx_ocotp_clr_err_if_set(struct ocotp_priv *priv)
writel(bm_ctrl_error, base + IMX_OCOTP_ADDR_CTRL_CLR);
}

-static int imx_ocotp_read(void *context, unsigned int offset,
+static ssize_t imx_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
@@ -217,7 +217,7 @@ static int imx_ocotp_read(void *context, unsigned int offset,

kfree(p);

- return ret;
+ return ret < 0 ? ret : bytes;
}

static int imx_ocotp_cell_pp(void *context, const char *id, int index,
@@ -307,7 +307,7 @@ static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
}

-static int imx_ocotp_write(void *context, unsigned int offset, void *val,
+static ssize_t imx_ocotp_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct ocotp_priv *priv = context;
diff --git a/drivers/nvmem/jz4780-efuse.c b/drivers/nvmem/jz4780-efuse.c
index 0b01b840edd9..3c3f57dd1ffc 100644
--- a/drivers/nvmem/jz4780-efuse.c
+++ b/drivers/nvmem/jz4780-efuse.c
@@ -66,10 +66,11 @@ struct jz4780_efuse {
};

/* main entry point */
-static int jz4780_efuse_read(void *context, unsigned int offset,
+static ssize_t jz4780_efuse_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct jz4780_efuse *efuse = context;
+ size_t bytes_read = bytes;

while (bytes > 0) {
size_t start = offset & ~(JZ_EFU_READ_SIZE - 1);
@@ -112,7 +113,7 @@ static int jz4780_efuse_read(void *context, unsigned int offset,
bytes -= chunk;
}

- return 0;
+ return bytes_read;
}

static struct nvmem_config jz4780_efuse_nvmem_config = {
diff --git a/drivers/nvmem/lan9662-otpc.c b/drivers/nvmem/lan9662-otpc.c
index 56fc19f092a7..a6bdc79867c7 100644
--- a/drivers/nvmem/lan9662-otpc.c
+++ b/drivers/nvmem/lan9662-otpc.c
@@ -119,7 +119,7 @@ static int lan9662_otp_write_byte(struct lan9662_otp *otp, u32 offset, u8 data)
return rc;
}

-static int lan9662_otp_read(void *context, unsigned int offset,
+static ssize_t lan9662_otp_read(void *context, unsigned int offset,
void *_val, size_t bytes)
{
struct lan9662_otp *otp = context;
@@ -136,10 +136,10 @@ static int lan9662_otp_read(void *context, unsigned int offset,
}
lan9662_otp_power(otp, false);

- return rc;
+ return rc < 0 ? rc : bytes;
}

-static int lan9662_otp_write(void *context, unsigned int offset,
+static ssize_t lan9662_otp_write(void *context, unsigned int offset,
void *_val, size_t bytes)
{
struct lan9662_otp *otp = context;
@@ -167,7 +167,7 @@ static int lan9662_otp_write(void *context, unsigned int offset,
}
lan9662_otp_power(otp, false);

- return rc;
+ return rc < 0 ? rc : bytes;
}

static struct nvmem_config otp_config = {
diff --git a/drivers/nvmem/layerscape-sfp.c b/drivers/nvmem/layerscape-sfp.c
index e2b424561949..0aab245abd6e 100644
--- a/drivers/nvmem/layerscape-sfp.c
+++ b/drivers/nvmem/layerscape-sfp.c
@@ -26,14 +26,17 @@ struct layerscape_sfp_data {
enum regmap_endian endian;
};

-static int layerscape_sfp_read(void *context, unsigned int offset, void *val,
+static ssize_t layerscape_sfp_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct layerscape_sfp_priv *priv = context;
+ int ret;

- return regmap_bulk_read(priv->regmap,
+ ret = regmap_bulk_read(priv->regmap,
LAYERSCAPE_SFP_OTP_OFFSET + offset, val,
bytes / 4);
+
+ return ret < 0 ? ret : bytes;
}

static struct nvmem_config layerscape_sfp_nvmem_config = {
diff --git a/drivers/nvmem/lpc18xx_eeprom.c b/drivers/nvmem/lpc18xx_eeprom.c
index a0275b29afd5..cc8f59c2cd63 100644
--- a/drivers/nvmem/lpc18xx_eeprom.c
+++ b/drivers/nvmem/lpc18xx_eeprom.c
@@ -87,10 +87,11 @@ static int lpc18xx_eeprom_busywait_until_prog(struct lpc18xx_eeprom_dev *eeprom)
return -ETIMEDOUT;
}

-static int lpc18xx_eeprom_gather_write(void *context, unsigned int reg,
+static ssize_t lpc18xx_eeprom_gather_write(void *context, unsigned int reg,
void *val, size_t bytes)
{
struct lpc18xx_eeprom_dev *eeprom = context;
+ size_t bytes_written = bytes;
unsigned int offset = reg;
int ret;

@@ -123,13 +124,14 @@ static int lpc18xx_eeprom_gather_write(void *context, unsigned int reg,
lpc18xx_eeprom_writel(eeprom, LPC18XX_EEPROM_PWRDWN,
LPC18XX_EEPROM_PWRDWN_YES);

- return 0;
+ return bytes_written;
}

-static int lpc18xx_eeprom_read(void *context, unsigned int offset,
+static ssize_t lpc18xx_eeprom_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct lpc18xx_eeprom_dev *eeprom = context;
+ size_t bytes_read = bytes;

lpc18xx_eeprom_writel(eeprom, LPC18XX_EEPROM_PWRDWN,
LPC18XX_EEPROM_PWRDWN_NO);
@@ -147,7 +149,7 @@ static int lpc18xx_eeprom_read(void *context, unsigned int offset,
lpc18xx_eeprom_writel(eeprom, LPC18XX_EEPROM_PWRDWN,
LPC18XX_EEPROM_PWRDWN_YES);

- return 0;
+ return bytes_read;
}


diff --git a/drivers/nvmem/lpc18xx_otp.c b/drivers/nvmem/lpc18xx_otp.c
index adc9948e7b2e..da7d7667e10c 100644
--- a/drivers/nvmem/lpc18xx_otp.c
+++ b/drivers/nvmem/lpc18xx_otp.c
@@ -37,7 +37,7 @@ struct lpc18xx_otp {
void __iomem *base;
};

-static int lpc18xx_otp_read(void *context, unsigned int offset,
+static ssize_t lpc18xx_otp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct lpc18xx_otp *otp = context;
@@ -52,7 +52,7 @@ static int lpc18xx_otp_read(void *context, unsigned int offset,
for (i = index; i < (index + count); i++)
*buf++ = readl(otp->base + i * LPC18XX_OTP_WORD_SIZE);

- return 0;
+ return bytes;
}

static struct nvmem_config lpc18xx_otp_nvmem_config = {
diff --git a/drivers/nvmem/meson-efuse.c b/drivers/nvmem/meson-efuse.c
index b922df99f9bc..da2e856b16a1 100644
--- a/drivers/nvmem/meson-efuse.c
+++ b/drivers/nvmem/meson-efuse.c
@@ -18,18 +18,24 @@ static int meson_efuse_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct meson_sm_firmware *fw = context;
+ int ret;

- return meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
+ ret = meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
bytes, 0, 0, 0);
+
+ return ret < 0 ? ret : bytes;
}

static int meson_efuse_write(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct meson_sm_firmware *fw = context;
+ int ret;

- return meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
+ ret = meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
bytes, 0, 0, 0);
+
+ return ret < 0 ? ret : bytes;
}

static const struct of_device_id meson_efuse_match[] = {
diff --git a/drivers/nvmem/meson-mx-efuse.c b/drivers/nvmem/meson-mx-efuse.c
index 3ff04d5ca8f8..fdc598adfe9e 100644
--- a/drivers/nvmem/meson-mx-efuse.c
+++ b/drivers/nvmem/meson-mx-efuse.c
@@ -132,7 +132,7 @@ static int meson_mx_efuse_read_addr(struct meson_mx_efuse *efuse,
return 0;
}

-static int meson_mx_efuse_read(void *context, unsigned int offset,
+static ssize_t meson_mx_efuse_read(void *context, unsigned int offset,
void *buf, size_t bytes)
{
struct meson_mx_efuse *efuse = context;
@@ -163,7 +163,7 @@ static int meson_mx_efuse_read(void *context, unsigned int offset,

meson_mx_efuse_hw_disable(efuse);

- return err;
+ return err < 0 ? err : bytes;
}

static const struct meson_mx_efuse_platform_data meson6_efuse_data = {
diff --git a/drivers/nvmem/microchip-otpc.c b/drivers/nvmem/microchip-otpc.c
index 7cf81738a3e0..9b53fcb75e98 100644
--- a/drivers/nvmem/microchip-otpc.c
+++ b/drivers/nvmem/microchip-otpc.c
@@ -143,7 +143,7 @@ static int mchp_otpc_prepare_read(struct mchp_otpc *otpc,
* packet. The user will have to be aware of the memory footprint before doing
* the read request.
*/
-static int mchp_otpc_read(void *priv, unsigned int off, void *val,
+static ssize_t mchp_otpc_read(void *priv, unsigned int off, void *val,
size_t bytes)
{
struct mchp_otpc *otpc = priv;
@@ -187,7 +187,7 @@ static int mchp_otpc_read(void *priv, unsigned int off, void *val,
} while (payload_size >= 0 && len < bytes);
}

- return 0;
+ return len;
}

static int mchp_otpc_init_packets_list(struct mchp_otpc *otpc, u32 *size)
diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
index 84f05b40a411..3819d416b505 100644
--- a/drivers/nvmem/mtk-efuse.c
+++ b/drivers/nvmem/mtk-efuse.c
@@ -20,7 +20,7 @@ struct mtk_efuse_priv {
void __iomem *base;
};

-static int mtk_reg_read(void *context,
+static ssize_t mtk_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct mtk_efuse_priv *priv = context;
@@ -31,7 +31,7 @@ static int mtk_reg_read(void *context,
for (i = 0; i < bytes; i++, val++)
*val = readb(addr + i);

- return 0;
+ return bytes;
}

static int mtk_efuse_gpu_speedbin_pp(void *context, const char *id, int index,
diff --git a/drivers/nvmem/mxs-ocotp.c b/drivers/nvmem/mxs-ocotp.c
index 7b78f18f9545..ddf7394de71b 100644
--- a/drivers/nvmem/mxs-ocotp.c
+++ b/drivers/nvmem/mxs-ocotp.c
@@ -56,10 +56,11 @@ static int mxs_ocotp_wait(struct mxs_ocotp *otp)
return 0;
}

-static int mxs_ocotp_read(void *context, unsigned int offset,
+static ssize_t mxs_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct mxs_ocotp *otp = context;
+ size_t bytes_read = bytes;
u32 *buf = val;
int ret;

@@ -102,7 +103,7 @@ static int mxs_ocotp_read(void *context, unsigned int offset,
disable_clk:
clk_disable(otp->clk);

- return ret;
+ return ret < 0 ? ret : bytes_read;
}

static struct nvmem_config ocotp_config = {
diff --git a/drivers/nvmem/nintendo-otp.c b/drivers/nvmem/nintendo-otp.c
index 355e7f1fc6d5..880f2915c030 100644
--- a/drivers/nvmem/nintendo-otp.c
+++ b/drivers/nvmem/nintendo-otp.c
@@ -45,7 +45,7 @@ static const struct nintendo_otp_devtype_data latte_otp_data = {
.num_banks = 8,
};

-static int nintendo_otp_reg_read(void *context,
+static ssize_t nintendo_otp_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct nintendo_otp_priv *priv = context;
@@ -61,7 +61,7 @@ static int nintendo_otp_reg_read(void *context,
reg += WORD_SIZE;
}

- return 0;
+ return bytes;
}

static const struct of_device_id nintendo_otp_of_table[] = {
diff --git a/drivers/nvmem/qcom-spmi-sdam.c b/drivers/nvmem/qcom-spmi-sdam.c
index 9aa8f42faa4c..c4dfde372794 100644
--- a/drivers/nvmem/qcom-spmi-sdam.c
+++ b/drivers/nvmem/qcom-spmi-sdam.c
@@ -60,7 +60,7 @@ static bool sdam_is_ro(unsigned int offset, size_t len)
return false;
}

-static int sdam_read(void *priv, unsigned int offset, void *val,
+static ssize_t sdam_read(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct sdam_chip *sdam = priv;
@@ -78,10 +78,10 @@ static int sdam_read(void *priv, unsigned int offset, void *val,
dev_err(dev, "Failed to read SDAM offset %#x len=%zd, rc=%d\n",
offset, bytes, rc);

- return rc;
+ return rc < 0 ? rc : bytes;
}

-static int sdam_write(void *priv, unsigned int offset, void *val,
+static ssize_t sdam_write(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct sdam_chip *sdam = priv;
@@ -105,7 +105,7 @@ static int sdam_write(void *priv, unsigned int offset, void *val,
dev_err(dev, "Failed to write SDAM offset %#x len=%zd, rc=%d\n",
offset, bytes, rc);

- return rc;
+ return rc < 0 ? rc : bytes;
}

static int sdam_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index 116a39e804c7..4d571ae6ba3e 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -251,9 +251,9 @@ static int qfprom_enable_fuse_blowing(const struct qfprom_priv *priv,
*
* Writes to fuses. WARNING: THIS IS PERMANENT.
*
- * Return: 0 or -err.
+ * Return: bytes written or -err.
*/
-static int qfprom_reg_write(void *context, unsigned int reg, void *_val,
+static ssize_t qfprom_reg_write(void *context, unsigned int reg, void *_val,
size_t bytes)
{
struct qfprom_priv *priv = context;
@@ -314,10 +314,10 @@ static int qfprom_reg_write(void *context, unsigned int reg, void *_val,
exit_enabled_fuse_blowing:
qfprom_disable_fuse_blowing(priv, &old);

- return ret;
+ return ret < 0 ? ret : bytes;
}

-static int qfprom_reg_read(void *context,
+static ssize_t qfprom_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct qfprom_priv *priv = context;
@@ -331,7 +331,7 @@ static int qfprom_reg_read(void *context,
while (words--)
*val++ = readb(base + reg + i++);

- return 0;
+ return bytes;
}

static void qfprom_runtime_disable(void *data)
diff --git a/drivers/nvmem/qoriq-efuse.c b/drivers/nvmem/qoriq-efuse.c
index e7fd04d6dd94..1e7315953e44 100644
--- a/drivers/nvmem/qoriq-efuse.c
+++ b/drivers/nvmem/qoriq-efuse.c
@@ -14,7 +14,7 @@ struct qoriq_efuse_priv {
void __iomem *base;
};

-static int qoriq_efuse_read(void *context, unsigned int offset, void *val,
+static ssize_t qoriq_efuse_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct qoriq_efuse_priv *priv = context;
@@ -24,7 +24,7 @@ static int qoriq_efuse_read(void *context, unsigned int offset, void *val,

/* Ignore trailing bytes (there shouldn't be any) */

- return 0;
+ return bytes;
}

static int qoriq_efuse_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/rave-sp-eeprom.c b/drivers/nvmem/rave-sp-eeprom.c
index 9ecf3873cbb7..6c8aecde8311 100644
--- a/drivers/nvmem/rave-sp-eeprom.c
+++ b/drivers/nvmem/rave-sp-eeprom.c
@@ -214,10 +214,10 @@ rave_sp_eeprom_page_access(struct rave_sp_eeprom *eeprom,
* arbitrary offset (not necessary page aligned) of arbitrary length
* (is not constrained by EEPROM page size).
*
- * Returns zero in case of success or negative error code in case of
- * failure.
+ * Returns number of bytes in case of success or negative error code
+ * in case of failure.
*/
-static int rave_sp_eeprom_access(struct rave_sp_eeprom *eeprom,
+static ssize_t rave_sp_eeprom_access(struct rave_sp_eeprom *eeprom,
enum rave_sp_eeprom_access_type type,
unsigned int offset, u8 *data,
unsigned int data_len)
@@ -267,17 +267,17 @@ static int rave_sp_eeprom_access(struct rave_sp_eeprom *eeprom,
} while (residue);
out:
mutex_unlock(&eeprom->mutex);
- return ret;
+ return ret < 0 ? ret : data_len;
}

-static int rave_sp_eeprom_reg_read(void *eeprom, unsigned int offset,
+static ssize_t rave_sp_eeprom_reg_read(void *eeprom, unsigned int offset,
void *val, size_t bytes)
{
return rave_sp_eeprom_access(eeprom, RAVE_SP_EEPROM_READ,
offset, val, bytes);
}

-static int rave_sp_eeprom_reg_write(void *eeprom, unsigned int offset,
+static ssize_t rave_sp_eeprom_reg_write(void *eeprom, unsigned int offset,
void *val, size_t bytes)
{
return rave_sp_eeprom_access(eeprom, RAVE_SP_EEPROM_WRITE,
diff --git a/drivers/nvmem/rmem.c b/drivers/nvmem/rmem.c
index 752d0bf4445e..1ddb832cd178 100644
--- a/drivers/nvmem/rmem.c
+++ b/drivers/nvmem/rmem.c
@@ -17,7 +17,7 @@ struct rmem {
phys_addr_t size;
};

-static int rmem_read(void *context, unsigned int offset,
+static ssize_t rmem_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rmem *priv = context;
diff --git a/drivers/nvmem/rockchip-efuse.c b/drivers/nvmem/rockchip-efuse.c
index 2b40978ddb18..fe05d7afd281 100644
--- a/drivers/nvmem/rockchip-efuse.c
+++ b/drivers/nvmem/rockchip-efuse.c
@@ -52,7 +52,7 @@ struct rockchip_efuse_chip {
struct clk *clk;
};

-static int rockchip_rk3288_efuse_read(void *context, unsigned int offset,
+static ssize_t rockchip_rk3288_efuse_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_efuse_chip *efuse = context;
@@ -65,6 +65,7 @@ static int rockchip_rk3288_efuse_read(void *context, unsigned int offset,
return ret;
}

+ ret = bytes;
writel(RK3288_LOAD | RK3288_PGENB, efuse->base + REG_EFUSE_CTRL);
udelay(1);
while (bytes--) {
@@ -89,7 +90,7 @@ static int rockchip_rk3288_efuse_read(void *context, unsigned int offset,

clk_disable_unprepare(efuse->clk);

- return 0;
+ return ret;
}

static int rockchip_rk3328_efuse_read(void *context, unsigned int offset,
@@ -144,10 +145,10 @@ static int rockchip_rk3328_efuse_read(void *context, unsigned int offset,
nomem:
clk_disable_unprepare(efuse->clk);

- return ret;
+ return ret < 0 ? ret : bytes;
}

-static int rockchip_rk3399_efuse_read(void *context, unsigned int offset,
+static ssize_t rockchip_rk3399_efuse_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_efuse_chip *efuse = context;
@@ -200,7 +201,7 @@ static int rockchip_rk3399_efuse_read(void *context, unsigned int offset,

clk_disable_unprepare(efuse->clk);

- return 0;
+ return bytes;
}

static struct nvmem_config econfig = {
diff --git a/drivers/nvmem/rockchip-otp.c b/drivers/nvmem/rockchip-otp.c
index cb9aa5428350..f7eb1feea978 100644
--- a/drivers/nvmem/rockchip-otp.c
+++ b/drivers/nvmem/rockchip-otp.c
@@ -144,10 +144,11 @@ static int rockchip_otp_ecc_enable(struct rockchip_otp *otp, bool enable)
return ret;
}

-static int px30_otp_read(void *context, unsigned int offset,
+static ssize_t px30_otp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_otp *otp = context;
+ size_t bytes_read = bytes;
u8 *buf = val;
int ret;

@@ -181,10 +182,10 @@ static int px30_otp_read(void *context, unsigned int offset,
read_end:
writel(0x0 | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL);

- return ret;
+ return ret < 0 ? ret : bytes_read;
}

-static int rk3588_otp_read(void *context, unsigned int offset,
+static ssize_t rk3588_otp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_otp *otp = context;
@@ -227,10 +228,10 @@ static int rk3588_otp_read(void *context, unsigned int offset,
read_end:
kfree(buf);

- return ret;
+ return ret < 0 ? ret : bytes;
}

-static int rockchip_otp_read(void *context, unsigned int offset,
+static ssize_t rockchip_otp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct rockchip_otp *otp = context;
@@ -249,7 +250,7 @@ static int rockchip_otp_read(void *context, unsigned int offset,

clk_bulk_disable_unprepare(otp->data->num_clks, otp->clks);

- return ret;
+ return ret < 0 ? ret : bytes;
}

static struct nvmem_config otp_config = {
diff --git a/drivers/nvmem/sc27xx-efuse.c b/drivers/nvmem/sc27xx-efuse.c
index bff27011f4ff..309ba1306939 100644
--- a/drivers/nvmem/sc27xx-efuse.c
+++ b/drivers/nvmem/sc27xx-efuse.c
@@ -121,7 +121,7 @@ static int sc27xx_efuse_poll_status(struct sc27xx_efuse *efuse, u32 bits)
return 0;
}

-static int sc27xx_efuse_read(void *context, u32 offset, void *val, size_t bytes)
+static ssize_t sc27xx_efuse_read(void *context, u32 offset, void *val, size_t bytes)
{
struct sc27xx_efuse *efuse = context;
u32 buf, blk_index = offset / SC27XX_EFUSE_BLOCK_WIDTH;
@@ -194,6 +194,7 @@ static int sc27xx_efuse_read(void *context, u32 offset, void *val, size_t bytes)
if (!ret) {
buf >>= blk_offset;
memcpy(val, &buf, bytes);
+ ret = bytes;
}

return ret;
diff --git a/drivers/nvmem/sec-qfprom.c b/drivers/nvmem/sec-qfprom.c
index 19799b3fe00a..dbacaab519e7 100644
--- a/drivers/nvmem/sec-qfprom.c
+++ b/drivers/nvmem/sec-qfprom.c
@@ -20,7 +20,7 @@ struct sec_qfprom {
struct device *dev;
};

-static int sec_qfprom_reg_read(void *context, unsigned int reg, void *_val, size_t bytes)
+static ssize_t sec_qfprom_reg_read(void *context, unsigned int reg, void *_val, size_t bytes)
{
struct sec_qfprom *priv = context;
unsigned int i;
@@ -40,7 +40,7 @@ static int sec_qfprom_reg_read(void *context, unsigned int reg, void *_val, size
val[i] = tmp[reg & 3];
}

- return 0;
+ return bytes;
}

static int sec_qfprom_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/snvs_lpgpr.c b/drivers/nvmem/snvs_lpgpr.c
index 89c27112320f..3019bf0c6271 100644
--- a/drivers/nvmem/snvs_lpgpr.c
+++ b/drivers/nvmem/snvs_lpgpr.c
@@ -50,7 +50,7 @@ static const struct snvs_lpgpr_cfg snvs_lpgpr_cfg_imx7d = {
.size = 16,
};

-static int snvs_lpgpr_write(void *context, unsigned int offset, void *val,
+static ssize_t snvs_lpgpr_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct snvs_lpgpr_priv *priv = context;
@@ -72,18 +72,23 @@ static int snvs_lpgpr_write(void *context, unsigned int offset, void *val,
if (lock_reg & IMX_GPR_HL)
return -EPERM;

- return regmap_bulk_write(priv->regmap, dcfg->offset + offset, val,
+ ret = regmap_bulk_write(priv->regmap, dcfg->offset + offset, val,
bytes / 4);
+
+ return ret < 0 ? ret : bytes;
}

-static int snvs_lpgpr_read(void *context, unsigned int offset, void *val,
+static ssize_t snvs_lpgpr_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct snvs_lpgpr_priv *priv = context;
const struct snvs_lpgpr_cfg *dcfg = priv->dcfg;
+ int ret;

- return regmap_bulk_read(priv->regmap, dcfg->offset + offset,
+ ret = regmap_bulk_read(priv->regmap, dcfg->offset + offset,
val, bytes / 4);
+
+ return ret < 0 ? ret : bytes;
}

static int snvs_lpgpr_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/sprd-efuse.c b/drivers/nvmem/sprd-efuse.c
index bb3105f3291f..5a1581df7555 100644
--- a/drivers/nvmem/sprd-efuse.c
+++ b/drivers/nvmem/sprd-efuse.c
@@ -291,7 +291,7 @@ static int sprd_efuse_raw_read(struct sprd_efuse *efuse, int blk, u32 *val,
return 0;
}

-static int sprd_efuse_read(void *context, u32 offset, void *val, size_t bytes)
+static ssize_t sprd_efuse_read(void *context, u32 offset, void *val, size_t bytes)
{
struct sprd_efuse *efuse = context;
bool blk_double = efuse->data->blk_double;
@@ -318,10 +318,10 @@ static int sprd_efuse_read(void *context, u32 offset, void *val, size_t bytes)

unlock:
sprd_efuse_unlock(efuse);
- return ret;
+ return ret < 0 ? ret : bytes;
}

-static int sprd_efuse_write(void *context, u32 offset, void *val, size_t bytes)
+static ssize_t sprd_efuse_write(void *context, u32 offset, void *val, size_t bytes)
{
struct sprd_efuse *efuse = context;
bool blk_double = efuse->data->blk_double;
@@ -355,7 +355,7 @@ static int sprd_efuse_write(void *context, u32 offset, void *val, size_t bytes)

unlock:
sprd_efuse_unlock(efuse);
- return ret;
+ return ret < 0 ? ret : bytes;
}

static int sprd_efuse_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/stm32-bsec-optee-ta.c b/drivers/nvmem/stm32-bsec-optee-ta.c
index f89ce791dd12..059f13af0886 100644
--- a/drivers/nvmem/stm32-bsec-optee-ta.c
+++ b/drivers/nvmem/stm32-bsec-optee-ta.c
@@ -136,7 +136,7 @@ void stm32_bsec_optee_ta_close(void *ctx)
}

/* stm32_bsec_optee_ta_read() - nvmem read access using PTA client driver */
-int stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
+ssize_t stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
void *buf, size_t bytes)
{
struct tee_shm *shm;
@@ -198,11 +198,11 @@ int stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
out_tee_session:
stm32_bsec_ta_close_session(ctx, session_id);

- return ret;
+ return ret < 0 ? ret : bytes;
}

/* stm32_bsec_optee_ta_write() - nvmem write access using PTA client driver */
-int stm32_bsec_optee_ta_write(struct tee_context *ctx, unsigned int lower,
+ssize_t stm32_bsec_optee_ta_write(struct tee_context *ctx, unsigned int lower,
unsigned int offset, void *buf, size_t bytes)
{ struct tee_shm *shm;
struct tee_ioctl_invoke_arg arg;
@@ -294,5 +294,5 @@ int stm32_bsec_optee_ta_write(struct tee_context *ctx, unsigned int lower,
out_tee_session:
stm32_bsec_ta_close_session(ctx, session_id);

- return ret;
+ return ret < 0 ? ret : bytes;
}
diff --git a/drivers/nvmem/stm32-bsec-optee-ta.h b/drivers/nvmem/stm32-bsec-optee-ta.h
index 3966a0535179..799f9f915150 100644
--- a/drivers/nvmem/stm32-bsec-optee-ta.h
+++ b/drivers/nvmem/stm32-bsec-optee-ta.h
@@ -33,9 +33,9 @@ void stm32_bsec_optee_ta_close(void *ctx);
* @bytes: number of bytes to read
*
* Return:
- * On success, 0. On failure, -errno.
+ * On success, bytes read. On failure, -errno.
*/
-int stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
+ssize_t stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
void *buf, size_t bytes);

/**
@@ -47,9 +47,9 @@ int stm32_bsec_optee_ta_read(struct tee_context *ctx, unsigned int offset,
* @bytes: number of bytes to write
*
* Return:
- * On success, 0. On failure, -errno.
+ * On success, bytes written. On failure, -errno.
*/
-int stm32_bsec_optee_ta_write(struct tee_context *ctx, unsigned int lower,
+ssize_t stm32_bsec_optee_ta_write(struct tee_context *ctx, unsigned int lower,
unsigned int offset, void *buf, size_t bytes);

#else
@@ -63,14 +63,14 @@ static inline void stm32_bsec_optee_ta_close(void *ctx)
{
}

-static inline int stm32_bsec_optee_ta_read(struct tee_context *ctx,
+static inline ssize_t stm32_bsec_optee_ta_read(struct tee_context *ctx,
unsigned int offset, void *buf,
size_t bytes)
{
return -EOPNOTSUPP;
}

-static inline int stm32_bsec_optee_ta_write(struct tee_context *ctx,
+static inline ssize_t stm32_bsec_optee_ta_write(struct tee_context *ctx,
unsigned int lower,
unsigned int offset, void *buf,
size_t bytes)
diff --git a/drivers/nvmem/stm32-romem.c b/drivers/nvmem/stm32-romem.c
index 82879b1c9eb9..a8c6983f9139 100644
--- a/drivers/nvmem/stm32-romem.c
+++ b/drivers/nvmem/stm32-romem.c
@@ -40,7 +40,7 @@ struct stm32_romem_priv {
struct tee_context *ctx;
};

-static int stm32_romem_read(void *context, unsigned int offset, void *buf,
+static ssize_t stm32_romem_read(void *context, unsigned int offset, void *buf,
size_t bytes)
{
struct stm32_romem_priv *priv = context;
@@ -50,7 +50,7 @@ static int stm32_romem_read(void *context, unsigned int offset, void *buf,
for (i = offset; i < offset + bytes; i++)
*buf8++ = readb_relaxed(priv->base + i);

- return 0;
+ return bytes;
}

static int stm32_bsec_smc(u8 op, u32 otp, u32 data, u32 *result)
@@ -71,7 +71,7 @@ static int stm32_bsec_smc(u8 op, u32 otp, u32 data, u32 *result)
#endif
}

-static int stm32_bsec_read(void *context, unsigned int offset, void *buf,
+static ssize_t stm32_bsec_read(void *context, unsigned int offset, void *buf,
size_t bytes)
{
struct stm32_romem_priv *priv = context;
@@ -115,10 +115,10 @@ static int stm32_bsec_read(void *context, unsigned int offset, void *buf,
skip_bytes = 0;
}

- return 0;
+ return bytes;
}

-static int stm32_bsec_write(void *context, unsigned int offset, void *buf,
+static ssize_t stm32_bsec_write(void *context, unsigned int offset, void *buf,
size_t bytes)
{
struct stm32_romem_priv *priv = context;
@@ -142,10 +142,10 @@ static int stm32_bsec_write(void *context, unsigned int offset, void *buf,
if (offset + bytes >= priv->lower * 4)
dev_warn(dev, "Update of upper OTPs with ECC protection (word programming, only once)\n");

- return 0;
+ return bytes;
}

-static int stm32_bsec_pta_read(void *context, unsigned int offset, void *buf,
+static ssize_t stm32_bsec_pta_read(void *context, unsigned int offset, void *buf,
size_t bytes)
{
struct stm32_romem_priv *priv = context;
@@ -153,7 +153,7 @@ static int stm32_bsec_pta_read(void *context, unsigned int offset, void *buf,
return stm32_bsec_optee_ta_read(priv->ctx, offset, buf, bytes);
}

-static int stm32_bsec_pta_write(void *context, unsigned int offset, void *buf,
+static ssize_t stm32_bsec_pta_write(void *context, unsigned int offset, void *buf,
size_t bytes)
{
struct stm32_romem_priv *priv = context;
diff --git a/drivers/nvmem/sunplus-ocotp.c b/drivers/nvmem/sunplus-ocotp.c
index 38f5d9df39cd..7bda128bb93e 100644
--- a/drivers/nvmem/sunplus-ocotp.c
+++ b/drivers/nvmem/sunplus-ocotp.c
@@ -114,7 +114,7 @@ static int sp_otp_read_real(struct sp_ocotp_priv *otp, int addr, char *value)
return ret;
}

-static int sp_ocotp_read(void *priv, unsigned int offset, void *value, size_t bytes)
+static ssize_t sp_ocotp_read(void *priv, unsigned int offset, void *value, size_t bytes)
{
struct sp_ocotp_priv *otp = priv;
unsigned int addr;
@@ -140,7 +140,7 @@ static int sp_ocotp_read(void *priv, unsigned int offset, void *value, size_t by
disable_clk:
clk_disable(otp->clk);

- return ret;
+ return ret < 0 ? ret : bytes;
}

static struct nvmem_config sp_ocotp_nvmem_config = {
diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c
index ba14a76208ab..26580c7a3c6d 100644
--- a/drivers/nvmem/sunxi_sid.c
+++ b/drivers/nvmem/sunxi_sid.c
@@ -36,7 +36,7 @@ struct sunxi_sid {
u32 value_offset;
};

-static int sunxi_sid_read(void *context, unsigned int offset,
+static ssize_t sunxi_sid_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct sunxi_sid *sid = context;
@@ -56,7 +56,7 @@ static int sunxi_sid_read(void *context, unsigned int offset,
word = readl_relaxed(sid->base + sid->value_offset + offset);
memcpy(val, &word, bytes);

- return 0;
+ return bytes;
}

static int sun8i_sid_register_readout(const struct sunxi_sid *sid,
@@ -90,10 +90,11 @@ static int sun8i_sid_register_readout(const struct sunxi_sid *sid,
* to be not reliable at all.
* Read by the registers instead.
*/
-static int sun8i_sid_read_by_reg(void *context, unsigned int offset,
+static ssize_t sun8i_sid_read_by_reg(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct sunxi_sid *sid = context;
+ size_t bytes_read = bytes;
u32 word;
int ret;

@@ -109,7 +110,7 @@ static int sun8i_sid_read_by_reg(void *context, unsigned int offset,
}

if (!bytes)
- return 0;
+ return bytes_read;

/* Handle any trailing bytes */
ret = sun8i_sid_register_readout(sid, offset, &word);
@@ -118,7 +119,7 @@ static int sun8i_sid_read_by_reg(void *context, unsigned int offset,

memcpy(val, &word, bytes);

- return 0;
+ return bytes_read;
}

static int sunxi_sid_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/u-boot-env.c b/drivers/nvmem/u-boot-env.c
index befbab156cda..a3cf63dfac2a 100644
--- a/drivers/nvmem/u-boot-env.c
+++ b/drivers/nvmem/u-boot-env.c
@@ -47,7 +47,7 @@ struct u_boot_env_image_broadcom {
DECLARE_FLEX_ARRAY(uint8_t, data);
} __packed;

-static int u_boot_env_read(void *context, unsigned int offset, void *val,
+static ssize_t u_boot_env_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct u_boot_env *priv = context;
@@ -66,7 +66,7 @@ static int u_boot_env_read(void *context, unsigned int offset, void *val,
return -EIO;
}

- return 0;
+ return bytes_read;
}

static int u_boot_env_read_post_process_ethaddr(void *context, const char *id, int index,
diff --git a/drivers/nvmem/uniphier-efuse.c b/drivers/nvmem/uniphier-efuse.c
index 6ad3295d3195..728c9af9fbe4 100644
--- a/drivers/nvmem/uniphier-efuse.c
+++ b/drivers/nvmem/uniphier-efuse.c
@@ -16,7 +16,7 @@ struct uniphier_efuse_priv {
void __iomem *base;
};

-static int uniphier_reg_read(void *context,
+static ssize_t uniphier_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct uniphier_efuse_priv *priv = context;
@@ -26,7 +26,7 @@ static int uniphier_reg_read(void *context,
for (offs = 0; offs < bytes; offs += sizeof(u8))
*val++ = readb(priv->base + reg + offs);

- return 0;
+ return bytes;
}

static int uniphier_efuse_probe(struct platform_device *pdev)
diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
index ee9c61ae727d..0ed91de61950 100644
--- a/drivers/nvmem/vf610-ocotp.c
+++ b/drivers/nvmem/vf610-ocotp.c
@@ -143,11 +143,12 @@ static int vf610_get_fuse_address(int base_addr_offset)
return -EINVAL;
}

-static int vf610_ocotp_read(void *context, unsigned int offset,
+static ssize_t vf610_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct vf610_ocotp *ocotp = context;
void __iomem *base = ocotp->base;
+ size_t bytes_read = bytes;
u32 reg, *buf = val;
int fuse_addr;
int ret;
@@ -193,7 +194,7 @@ static int vf610_ocotp_read(void *context, unsigned int offset,
offset += 4;
}

- return 0;
+ return bytes_read;
}

static struct nvmem_config ocotp_config = {
diff --git a/drivers/nvmem/zynqmp_nvmem.c b/drivers/nvmem/zynqmp_nvmem.c
index 7f15aa89a9d0..50f8497cc17a 100644
--- a/drivers/nvmem/zynqmp_nvmem.c
+++ b/drivers/nvmem/zynqmp_nvmem.c
@@ -30,7 +30,7 @@ static int zynqmp_nvmem_read(void *context, unsigned int offset,
dev_dbg(priv->dev, "Read chipid val %x %x\n", idcode, version);
*(int *)val = version & SILICON_REVISION_MASK;

- return 0;
+ return bytes;
}

static struct nvmem_config econfig = {
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index f0ba0e03218f..2cdab3fec2be 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -16,9 +16,9 @@
#include <linux/gpio/consumer.h>

struct nvmem_device;
-typedef int (*nvmem_reg_read_t)(void *priv, unsigned int offset,
+typedef ssize_t (*nvmem_reg_read_t)(void *priv, unsigned int offset,
void *val, size_t bytes);
-typedef int (*nvmem_reg_write_t)(void *priv, unsigned int offset,
+typedef ssize_t (*nvmem_reg_write_t)(void *priv, unsigned int offset,
void *val, size_t bytes);
/* used for vendor specific post processing of cell data */
typedef int (*nvmem_cell_post_process_t)(void *priv, const char *id, int index,
--
2.44.0.rc0.258.g7320e95886-goog