linux-kernel - Re: [PATCH] eeprom: at24: code shrink

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Date:   Mon, 18 Dec 2017 18:45:47 +0100
From:   Bartosz Golaszewski <brgl@...ev.pl>
To:     linux-i2c <linux-i2c@...r.kernel.org>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Bartosz Golaszewski <brgl@...ev.pl>
Subject: Re: [PATCH] eeprom: at24: code shrink

2017-12-10 20:29 GMT+01:00 Bartosz Golaszewski <brgl@...ev.pl>:
> A regmap_config struct is pretty big and declaring two of them
> statically just to tweak the reg_bits value adds unnecessary bloat.
>
> Declare the regmap config locally in at24_probe() instead.
>
> Bloat-o-meter output:
>
> add/remove: 0/2 grow/shrink: 1/0 up/down: 20/-272 (-252)
> Function                                     old     new   delta
> at24_probe                                  1564    1584     +20
> regmap_config_8                              136       -    -136
> regmap_config_16                             136       -    -136
> Total: Before=7010, After=6758, chg -3.59%
>
> Signed-off-by: Bartosz Golaszewski <brgl@...ev.pl>
> ---
>  drivers/misc/eeprom/at24.c | 27 ++++++---------------------
>  1 file changed, 6 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index ded86474b3de..5ecddbc74732 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -518,20 +518,6 @@ static void at24_regmap_lock_unlock_none(void *map)
>
>  }
>
> -static const struct regmap_config regmap_config_8 = {
> -       .reg_bits = 8,
> -       .val_bits = 8,
> -       .lock = at24_regmap_lock_unlock_none,
> -       .unlock = at24_regmap_lock_unlock_none,
> -};
> -
> -static const struct regmap_config regmap_config_16 = {
> -       .reg_bits = 16,
> -       .val_bits = 8,
> -       .lock = at24_regmap_lock_unlock_none,
> -       .unlock = at24_regmap_lock_unlock_none,
> -};
> -
>  static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  {
>         struct at24_platform_data chip;
> @@ -540,7 +526,7 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>         struct at24_data *at24;
>         int err;
>         unsigned i, num_addresses;
> -       const struct regmap_config *config;
> +       struct regmap_config config = { };
>         u8 test_byte;
>
>         if (client->dev.platform_data) {
> @@ -609,10 +595,9 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>                 num_addresses = DIV_ROUND_UP(chip.byte_len,
>                         (chip.flags & AT24_FLAG_ADDR16) ? 65536 : 256);
>
> -       if (chip.flags & AT24_FLAG_ADDR16)
> -               config = &regmap_config_16;
> -       else
> -               config = &regmap_config_8;
> +       config.val_bits = 8;
> +       config.lock = config.unlock = at24_regmap_lock_unlock_none;
> +       config.reg_bits = (chip.flags & AT24_FLAG_ADDR16) ? 16 : 8;
>
>         at24 = devm_kzalloc(&client->dev, sizeof(struct at24_data) +
>                 num_addresses * sizeof(struct at24_client), GFP_KERNEL);
> @@ -625,7 +610,7 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>         at24->offset_adj = at24_get_offset_adj(chip.flags, chip.byte_len);
>
>         at24->client[0].client = client;
> -       at24->client[0].regmap = devm_regmap_init_i2c(client, config);
> +       at24->client[0].regmap = devm_regmap_init_i2c(client, &config);
>         if (IS_ERR(at24->client[0].regmap))
>                 return PTR_ERR(at24->client[0].regmap);
>
> @@ -654,7 +639,7 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>                         goto err_clients;
>                 }
>                 at24->client[i].regmap = devm_regmap_init_i2c(
> -                                       at24->client[i].client, config);
> +                                       at24->client[i].client, &config);
>                 if (IS_ERR(at24->client[i].regmap)) {
>                         err = PTR_ERR(at24->client[i].regmap);
>                         goto err_clients;
> --
> 2.15.1
>

There were no more comments, so patch applied.