On 30.01.2024 01:23, Andi Shyti wrote:
> On Fri, Sep 22, 2023 at 09:40:25PM +0200, Heiner Kallweit wrote:
>> Add a sentinel length value that is used to check whether we should
>> read and use the length value provided by the slave device.
>> This simplifies the currently used checks.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
>> ---
>> drivers/i2c/busses/i2c-i801.c | 10 +++++-----
>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
>> index a9d3dfd9e..30a2f9268 100644
>> --- a/drivers/i2c/busses/i2c-i801.c
>> +++ b/drivers/i2c/busses/i2c-i801.c
>> @@ -204,6 +204,8 @@
>> #define STATUS_FLAGS (SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR | \
>> STATUS_ERROR_FLAGS)
>>
>> +#define SMBUS_LEN_SENTINEL (I2C_SMBUS_BLOCK_MAX + 1)
>> +
>> /* Older devices have their ID defined in <linux/pci_ids.h> */
>> #define PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS 0x02a3
>> #define PCI_DEVICE_ID_INTEL_COMETLAKE_H_SMBUS 0x06a3
>> @@ -541,8 +543,7 @@ static void i801_isr_byte_done(struct i801_priv *priv)
>> {
>> if (priv->is_read) {
>> /* For SMBus block reads, length is received with first byte */
>> - if (((priv->cmd & 0x1c) == I801_BLOCK_DATA) &&
>> - (priv->count == 0)) {
>> + if (priv->len == SMBUS_LEN_SENTINEL) {
>> priv->len = inb_p(SMBHSTDAT0(priv));
>> if (priv->len < 1 || priv->len > I2C_SMBUS_BLOCK_MAX) {
>> dev_err(&priv->pci_dev->dev,
>> @@ -697,8 +698,7 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
>> if (status)
>> return status;
>>
>> - if (i == 1 && read_write == I2C_SMBUS_READ
>> - && command != I2C_SMBUS_I2C_BLOCK_DATA) {
>> + if (len == SMBUS_LEN_SENTINEL) {
>> len = inb_p(SMBHSTDAT0(priv));
>> if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
>> dev_err(&priv->pci_dev->dev,
>> @@ -805,7 +805,7 @@ static int i801_smbus_block_transaction(struct i801_priv *priv, union i2c_smbus_
>> u8 addr, u8 hstcmd, char read_write, int command)
>> {
>> if (read_write == I2C_SMBUS_READ && command == I2C_SMBUS_BLOCK_DATA)
>> - data->block[0] = I2C_SMBUS_BLOCK_MAX;
>> + data->block[0] = SMBUS_LEN_SENTINEL;
>
> This patch is good, but a few comments for each change to tell
> where the sentinel will be used and where the sentinel was set
> would help to better understand the use of the sentinel.
>
OK
> Thanks,
> Andi
>
>> else if (data->block[0] < 1 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
>> return -EPROTO;
>>
>> --
>> 2.42.0
>>
>>
