linux-kernel - [PATCH RFC 3/3] ipmi: remove open coded version of SMBus block write

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Date:   Tue, 12 Jan 2021 17:41:29 +0100
From:   Wolfram Sang <wsa+renesas@...g-engineering.com>
To:     linux-i2c@...r.kernel.org
Cc:     Wolfram Sang <wsa+renesas@...g-engineering.com>,
        Corey Minyard <minyard@....org>,
        openipmi-developer@...ts.sourceforge.net,
        linux-kernel@...r.kernel.org
Subject: [PATCH RFC 3/3] ipmi: remove open coded version of SMBus block write

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@...g-engineering.com>
---
 drivers/char/ipmi/ipmb_dev_int.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/char/ipmi/ipmb_dev_int.c b/drivers/char/ipmi/ipmb_dev_int.c
index 382b28f1cf2f..10d89886e5f3 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 +160,16 @@ 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;
+	memcpy(&temp_client, ipmb_dev->client, sizeof(temp_client));
+	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);
-
-	return ret ? : count;
+	ret = i2c_smbus_write_block_data(&temp_client, netf_rq_lun, msg_len,
+					 msg + SMBUS_MSG_IDX_OFFSET);
+	return ret < 0 ? ret : count;
 }
 
 static __poll_t ipmb_poll(struct file *file, poll_table *wait)
-- 
2.29.2