Re: [PATCH v19 4/5] tpm: tpm_tis: Add tpm_tis_i2c driver

[Joel Stanley]

On Thu, 4 Nov 2021 at 14:04, <amirmizi6@xxxxxxxxx> wrote:


> +static int tpm_tis_i2c_write_bytes(struct tpm_tis_data *data, u32 addr,
> +                                  u16 len, const u8 *value)
> +{
> +       struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data);
> +       int ret = 0;
> +       int i = 0;
> +
> +       if (phy->iobuf) {
> +               if (len > TPM_BUFSIZE - 1)
> +                       return -EIO;
> +
> +               phy->iobuf[0] = address_to_register(addr);
> +               memcpy(phy->iobuf + 1, value, len);
> +
> +               struct i2c_msg msgs[] = {
> +                       {
> +                               .addr = phy->i2c_client->addr,
> +                               .len = len + 1,
> +                               .buf = phy->iobuf,
> +                       },
> +               };

I see this warning with GCC 11.2:

../drivers/char/tpm/tpm_tis_i2c.c: In function ‘tpm_tis_i2c_write_bytes’:
../drivers/char/tpm/tpm_tis_i2c.c:114:17: warning: ISO C90 forbids
mixed declarations and code [-Wdeclaration-after-statement]

> +
> +               do {
> +                       ret = i2c_transfer(phy->i2c_client->adapter,
> +                                          msgs, ARRAY_SIZE(msgs));
> +                       // wait default GUARD_TIME of 250µs
> +                       usleep_range(250, 300);
> +               } while (ret < 0 && i++ < TPM_RETRY);
> +       } else {
> +               u8 reg = address_to_register(addr);
> +
> +               struct i2c_msg msgs[] = {
> +                       {
> +                               .addr = phy->i2c_client->addr,
> +                               .len = sizeof(reg),
> +                               .buf = &reg,
> +                       },
> +                       {
> +                               .addr = phy->i2c_client->addr,
> +                               .len = len,
> +                               .buf = (u8 *)value,
> +                               .flags = I2C_M_NOSTART,
> +                       },
> +               };
> +
> +               do {
> +                       ret = i2c_transfer(phy->i2c_client->adapter, msgs,
> +                                          ARRAY_SIZE(msgs));
> +                       // wait default GUARD_TIME of 250µs
> +                       usleep_range(250, 300);
> +               } while (ret < 0 && i++ < TPM_RETRY);
> +       }
> +
> +       if (ret < 0)
> +               return ret;
> +
> +       return 0;
> +}
> +
> +int tpm_tis_i2c_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
> +{
> +       __le16 result_le;
> +       int rc;
> +
> +       rc = data->phy_ops->read_bytes(data, addr, sizeof(u16),
> +                                      (u8 *)&result_le);
> +       if (!rc)
> +               *result = le16_to_cpu(result_le);
> +
> +       return rc;
> +}
> +
> +int tpm_tis_i2c_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
> +{
> +       __le32 result_le;
> +       int rc;
> +
> +       rc = data->phy_ops->read_bytes(data, addr, sizeof(u32),
> +                                      (u8 *)&result_le);
> +       if (!rc)
> +               *result = le32_to_cpu(result_le);
> +
> +       return rc;
> +}
> +
> +int tpm_tis_i2c_write32(struct tpm_tis_data *data, u32 addr, u32 value)
> +{
> +       __le32 value_le;
> +       int rc;
> +
> +       value_le = cpu_to_le32(value);
> +
> +       rc = data->phy_ops->write_bytes(data, addr, sizeof(u32),
> +                                       (u8 *)&value_le);
> +
> +       return rc;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
> +
> +static const struct tpm_tis_phy_ops tpm_i2c_phy_ops = {
> +       .read_bytes = tpm_tis_i2c_read_bytes,
> +       .write_bytes = tpm_tis_i2c_write_bytes,
> +       .read16 = tpm_tis_i2c_read16,
> +       .read32 = tpm_tis_i2c_read32,
> +       .write32 = tpm_tis_i2c_write32,
> +};
> +
> +static int tpm_tis_i2c_probe(struct i2c_client *dev, const struct i2c_device_id *id)
> +{
> +       struct tpm_tis_i2c_phy *phy;
> +       const u8 loc_init = 0;
> +       int rc;
> +
> +       phy = devm_kzalloc(&dev->dev, sizeof(struct tpm_tis_i2c_phy),
> +                          GFP_KERNEL);
> +       if (!phy)
> +               return -ENOMEM;
> +
> +       phy->i2c_client = dev;
> +
> +       if (!i2c_check_functionality(dev->adapter, I2C_FUNC_NOSTART)) {
> +               phy->iobuf = devm_kmalloc(&dev->dev, TPM_BUFSIZE, GFP_KERNEL);
> +               if (!phy->iobuf)
> +                       return -ENOMEM;
> +       }
> +
> +       /*select locality 0 (the driver will access only via locality 0)*/
> +       rc = tpm_tis_i2c_write_bytes(&phy->priv, TPM_LOC_SEL, 1, &loc_init);
> +       if (rc < 0)
> +               return rc;
> +
> +       return tpm_tis_core_init(&dev->dev, &phy->priv, -1, &tpm_i2c_phy_ops,
> +                                       NULL);
> +}
> +
> +static const struct i2c_device_id tpm_tis_i2c_id[] = {
> +       {"tpm_tis_i2c", 0},
> +       {}
> +};
> +MODULE_DEVICE_TABLE(i2c, tpm_tis_i2c_id);
> +
> +static const struct of_device_id of_tis_i2c_match[] = {
> +       { .compatible = "nuvoton,npct75x", },
> +       { .compatible = "tcg,tpm-tis-i2c", },
> +       {}
> +};
> +MODULE_DEVICE_TABLE(of, of_tis_i2c_match);
> +
> +static struct i2c_driver tpm_tis_i2c_driver = {
> +       .driver = {
> +               .owner = THIS_MODULE,
> +               .name = "tpm_tis_i2c",
> +               .pm = &tpm_tis_pm,
> +               .of_match_table = of_match_ptr(of_tis_i2c_match),
> +       },
> +       .probe = tpm_tis_i2c_probe,
> +       .id_table = tpm_tis_i2c_id,
> +};
> +
> +module_i2c_driver(tpm_tis_i2c_driver);
> +
> +MODULE_DESCRIPTION("TPM Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.7.4
>