[PATCH 08/13] eeprom: at24: call read and write routines via function pointers

From: Bartosz Golaszewski
Date: Thu Mar 24 2016 - 10:53:17 EST


In order to support non-standard read/write functions (as part of the
at24cs series support) introduce two function pointers in struct
at24_data to which different implementations can be assigned.

For now we continue to use the regular read/write routines by default.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
---
drivers/misc/eeprom/at24.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index a7d6c15..5b484bc 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -59,6 +59,9 @@ struct at24_data {
int use_smbus;
int use_smbus_write;

+ int (*read_func)(struct at24_data *, char *, loff_t, size_t);
+ int (*write_func)(struct at24_data *, const char *, loff_t, size_t);
+
u8 *writebuf;
struct mutex wrbuf_lock;
unsigned write_max;
@@ -458,7 +461,7 @@ static int at24_regmap_read(void *context, const void *reg, size_t reg_size,
off_t offset = *(u32 *)reg;
int err;

- err = at24_read(at24, val, offset, val_size);
+ err = at24->read_func(at24, val, offset, val_size);
if (err)
return err;
return 0;
@@ -476,7 +479,7 @@ static int at24_regmap_write(void *context, const void *data, size_t count)
buf = (const char *)data + sizeof(offset);
len = count - sizeof(offset);

- err = at24_write(at24, buf, offset, len);
+ err = at24->write_func(at24, buf, offset, len);
if (err)
return err;
return 0;
@@ -611,6 +614,9 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
at24->chip = chip;
at24->num_addresses = num_addresses;

+ at24->read_func = at24_read;
+ at24->write_func = at24_write;
+
writable = !(chip.flags & AT24_FLAG_READONLY);
if (writable) {
if (!use_smbus || use_smbus_write) {
--
2.7.4