Re: [PATCH RESEND] ipmi: remove open coded version of SMBus block write

From: Corey Minyard
Date: Thu Jan 28 2021 - 07:39:06 EST


Looks good, do you want this in the IPMI tree or are you handling this
another way?

Thanks,

-corey

On Thu, Jan 28, 2021 at 09:55:43AM +0100, Wolfram Sang wrote:
> The block-write function of the core was not used because there was no
> client-struct to use. However, in this case it seems apropriate to use a
> temporary client struct. Because we are answering a request we recieved
> when being a client ourselves. So, convert the code to use a temporary
> client and use the block-write function of the I2C core.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
> Acked-by: Corey Minyard <cminyard@xxxxxxxxxx>
> ---
>
> No change since V1, Only added tags given in private communication.
>
> drivers/char/ipmi/ipmb_dev_int.c | 24 ++++++++++++------------
> 1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/char/ipmi/ipmb_dev_int.c b/drivers/char/ipmi/ipmb_dev_int.c
> index 382b28f1cf2f..49b8f22fdcf0 100644
> --- a/drivers/char/ipmi/ipmb_dev_int.c
> +++ b/drivers/char/ipmi/ipmb_dev_int.c
> @@ -137,7 +137,7 @@ static ssize_t ipmb_write(struct file *file, const char __user *buf,
> {
> struct ipmb_dev *ipmb_dev = to_ipmb_dev(file);
> u8 rq_sa, netf_rq_lun, msg_len;
> - union i2c_smbus_data data;
> + struct i2c_client *temp_client;
> u8 msg[MAX_MSG_LEN];
> ssize_t ret;
>
> @@ -160,21 +160,21 @@ static ssize_t ipmb_write(struct file *file, const char __user *buf,
> }
>
> /*
> - * subtract rq_sa and netf_rq_lun from the length of the msg passed to
> - * i2c_smbus_xfer
> + * subtract rq_sa and netf_rq_lun from the length of the msg. Fill the
> + * temporary client. Note that its use is an exception for IPMI.
> */
> msg_len = msg[IPMB_MSG_LEN_IDX] - SMBUS_MSG_HEADER_LENGTH;
> - if (msg_len > I2C_SMBUS_BLOCK_MAX)
> - msg_len = I2C_SMBUS_BLOCK_MAX;
> + temp_client = kmemdup(ipmb_dev->client, sizeof(*temp_client), GFP_KERNEL);
> + if (!temp_client)
> + return -ENOMEM;
> +
> + temp_client->addr = rq_sa;
>
> - data.block[0] = msg_len;
> - memcpy(&data.block[1], msg + SMBUS_MSG_IDX_OFFSET, msg_len);
> - ret = i2c_smbus_xfer(ipmb_dev->client->adapter, rq_sa,
> - ipmb_dev->client->flags,
> - I2C_SMBUS_WRITE, netf_rq_lun,
> - I2C_SMBUS_BLOCK_DATA, &data);
> + ret = i2c_smbus_write_block_data(temp_client, netf_rq_lun, msg_len,
> + msg + SMBUS_MSG_IDX_OFFSET);
> + kfree(temp_client);
>
> - return ret ? : count;
> + return ret < 0 ? ret : count;
> }
>
> static __poll_t ipmb_poll(struct file *file, poll_table *wait)
> --
> 2.28.0
>