2017-11-22 8:05 GMT+01:00 Heiner Kallweit <hkallweit1@xxxxxxxxx>:
> Add regmap-based read function and instead of using three different
> read functions (standard, mac, serial) use just one and factor out the
> read offset adjustment for mac and serial to at24_adjust_read_offset.
>
> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
> ---
> v2:
> - rebased
> v3:
> - improve readability
> - re-introduce debug message
> - introduce at24_adjust_read_offset
> ---
> drivers/misc/eeprom/at24.c | 53 +++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 52 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 493e2b646..589e6d855 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -312,6 +312,57 @@ static ssize_t at24_eeprom_read_smbus(struct at24_data *at24, char *buf,
> return -ETIMEDOUT;
> }
>
> +static void at24_adjust_read_offset(struct at24_data *at24,
> + unsigned int *offset)
> +{
> + u8 flags = at24->chip.flags;
> +
> + if (flags & AT24_FLAG_MAC)
> + *offset += 0x90;
Ok, so I missed this last time. On the other hand we could avoid this
function and all these if elses if we added an unsigned int called for
example: offset_adj to struct at24_data. It could be initialized in
probe() to whatever value is needed according to the flags and then
or'ed right before reading from the regmap in at24_regmap_read(). How
about that?
> + else if (flags & AT24_FLAG_SERIAL && flags & AT24_FLAG_ADDR16)
> + /*
> + * For 16 bit address pointers, the word address must contain
> + * a '10' sequence in bits 11 and 10 regardless of the
> + * intended position of the address pointer.
> + */
> + *offset |= BIT(11);
> + else if (flags & AT24_FLAG_SERIAL)
> + /*
> + * Otherwise the word address must begin with a '10' sequence,
> + * regardless of the intended address.
> + */
> + *offset |= BIT(7);
> +}
> +
> +static ssize_t at24_regmap_read(struct at24_data *at24, char *buf,
> + unsigned int offset, size_t count)
> +{
> + unsigned long timeout, read_time;
> + struct at24_client *at24_client;
> + struct i2c_client *client;
> + struct regmap *regmap;
> + int ret;
> +
> + at24_client = at24_translate_offset(at24, &offset);
> + regmap = at24_client->regmap;
> + client = at24_client->client;
> +
> + if (count > io_limit)
> + count = io_limit;
> +
> + at24_adjust_read_offset(at24, &offset);
> +
> + loop_until_timeout(timeout, read_time) {
> + ret = regmap_bulk_read(regmap, offset, buf, count);
> + dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n",
> + count, offset, ret, jiffies);
> + if (!ret)
> + return count;
> + }
> +
> + return -ETIMEDOUT;
> +}
> +
> static ssize_t at24_eeprom_read_i2c(struct at24_data *at24, char *buf,
> unsigned int offset, size_t count)
> {
> @@ -531,7 +582,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
> while (count) {
> int status;
>
> - status = at24->read_func(at24, buf, off, count);
> + status = at24_regmap_read(at24, buf, off, count);
> if (status < 0) {
> mutex_unlock(&at24->lock);
> pm_runtime_put(&client->dev);
> --
> 2.15.0
>
>
