eeprom: at25: remove nvmem regmap dependency

This patch moves to nvmem support in the driver to use callback instead
of regmap.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 19 insertions, 71 deletions

diff --git a/drivers/misc/eeprom/Kconfig b/drivers/misc/eeprom/Kconfig
index 2d70464e8c8d..c4e41c26649e 100644
--- a/drivers/misc/eeprom/Kconfig
+++ b/drivers/misc/eeprom/Kconfig
@@ -31,7 +31,6 @@ config EEPROM_AT24
 config EEPROM_AT25
         tristate "SPI EEPROMs from most vendors"
         depends on SPI && SYSFS
-        select REGMAP
         select NVMEM
         help
           Enable this driver to get read/write support to most SPI EEPROMs,
diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index fa36a6e37084..a2858b33585e 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c
@@ -17,7 +17,6 @@
 #include <linux/sched.h>
 
 #include <linux/nvmem-provider.h>
-#include <linux/regmap.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/eeprom.h>
 #include <linux/property.h>
@@ -34,7 +33,6 @@ struct at25_data {
         struct mutex            lock;
         struct spi_eeprom       chip;
         unsigned                addrlen;
-        struct regmap_config    regmap_config;
         struct nvmem_config     nvmem_config;
         struct nvmem_device     *nvmem;
 };
@@ -65,14 +63,11 @@ struct at25_data {
 
 #define io_limit        PAGE_SIZE       /* bytes */
 
-static ssize_t
-at25_ee_read(
-        struct at25_data        *at25,
-        char                    *buf,
-        unsigned                offset,
-        size_t                  count
-)
+static int at25_ee_read(void *priv, unsigned int offset,
+                        void *val, size_t count)
 {
+        struct at25_data *at25 = priv;
+        char *buf = val;
         u8                      command[EE_MAXADDRLEN + 1];
         u8                      *cp;
         ssize_t                 status;
@@ -81,11 +76,11 @@ at25_ee_read(
         u8                      instr;
 
         if (unlikely(offset >= at25->chip.byte_len))
-                return 0;
+                return -EINVAL;
         if ((offset + count) > at25->chip.byte_len)
                 count = at25->chip.byte_len - offset;
         if (unlikely(!count))
-                return count;
+                return -EINVAL;
 
         cp = command;
 
@@ -131,28 +126,14 @@ at25_ee_read(
                 count, offset, (int) status);
 
         mutex_unlock(&at25->lock);
-        return status ? status : count;
+        return status;
 }
 
-static int at25_regmap_read(void *context, const void *reg, size_t reg_size,
-                            void *val, size_t val_size)
+static int at25_ee_write(void *priv, unsigned int off, void *val, size_t count)
 {
-        struct at25_data *at25 = context;
-        off_t offset = *(u32 *)reg;
-        int err;
-
-        err = at25_ee_read(at25, val, offset, val_size);
-        if (err)
-                return err;
-        return 0;
-}
-
-static ssize_t
-at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
-              size_t count)
-{
-        ssize_t                 status = 0;
-        unsigned                written = 0;
+        struct at25_data *at25 = priv;
+        const char *buf = val;
+        int                     status = 0;
         unsigned                buf_size;
         u8                      *bounce;
 
@@ -161,7 +142,7 @@ at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
         if ((off + count) > at25->chip.byte_len)
                 count = at25->chip.byte_len - off;
         if (unlikely(!count))
-                return count;
+                return -EINVAL;
 
         /* Temp buffer starts with command and address */
         buf_size = at25->chip.page_size;
@@ -256,40 +237,15 @@ at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
                 off += segment;
                 buf += segment;
                 count -= segment;
-                written += segment;
 
         } while (count > 0);
 
         mutex_unlock(&at25->lock);
 
         kfree(bounce);
-        return written ? written : status;
+        return status;
 }
 
-static int at25_regmap_write(void *context, const void *data, size_t count)
-{
-        struct at25_data *at25 = context;
-        const char *buf;
-        u32 offset;
-        size_t len;
-        int err;
-
-        memcpy(&offset, data, sizeof(offset));
-        buf = (const char *)data + sizeof(offset);
-        len = count - sizeof(offset);
-
-        err = at25_ee_write(at25, buf, offset, len);
-        if (err)
-                return err;
-        return 0;
-}
-
-static const struct regmap_bus at25_regmap_bus = {
-        .read = at25_regmap_read,
-        .write = at25_regmap_write,
-        .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
-};
-
 /*-------------------------------------------------------------------------*/
 
 static int at25_fw_to_chip(struct device *dev, struct spi_eeprom *chip)
@@ -349,7 +305,6 @@ static int at25_probe(struct spi_device *spi)
 {
         struct at25_data        *at25 = NULL;
         struct spi_eeprom       chip;
-        struct regmap           *regmap;
         int                     err;
         int                     sr;
         int                     addrlen;
@@ -394,18 +349,6 @@ static int at25_probe(struct spi_device *spi)
         spi_set_drvdata(spi, at25);
         at25->addrlen = addrlen;
 
-        at25->regmap_config.reg_bits = 32;
-        at25->regmap_config.val_bits = 8;
-        at25->regmap_config.reg_stride = 1;
-        at25->regmap_config.max_register = chip.byte_len - 1;
-
-        regmap = devm_regmap_init(&spi->dev, &at25_regmap_bus, at25,
-                                  &at25->regmap_config);
-        if (IS_ERR(regmap)) {
-                dev_err(&spi->dev, "regmap init failed\n");
-                return PTR_ERR(regmap);
-        }
-
         at25->nvmem_config.name = dev_name(&spi->dev);
         at25->nvmem_config.dev = &spi->dev;
         at25->nvmem_config.read_only = chip.flags & EE_READONLY;
@@ -413,6 +356,12 @@ static int at25_probe(struct spi_device *spi)
         at25->nvmem_config.owner = THIS_MODULE;
         at25->nvmem_config.compat = true;
         at25->nvmem_config.base_dev = &spi->dev;
+        at25->nvmem_config.reg_read = at25_ee_read;
+        at25->nvmem_config.reg_write = at25_ee_write;
+        at25->nvmem_config.priv = at25;
+        at25->nvmem_config.stride = 4;
+        at25->nvmem_config.word_size = 1;
+        at25->nvmem_config.size = chip.byte_len;
 
         at25->nvmem = nvmem_register(&at25->nvmem_config);
         if (IS_ERR(at25->nvmem))