The Process Call command is implemented by the hardware since the very first Intel 82801 chipset, and trivial to support. Oscar Romero Matamala from the Georgia Institute of Technology told me it is needed for an experiment his team is working on at the moment, so let's just add support for it. Signed-off-by: Jean Delvare <jdelvare@xxxxxxx> --- Disclaimer: untested code. I don't have any device at hand which supports the Process Call command so I just can't test it. If anyone has a chance, please test. If not, I hope Oscar will be able to test it soon. drivers/i2c/busses/i2c-i801.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- linux-5.16.orig/drivers/i2c/busses/i2c-i801.c 2022-03-01 17:06:42.685102412 +0100 +++ linux-5.16/drivers/i2c/busses/i2c-i801.c 2022-03-01 17:35:49.586064557 +0100 @@ -166,7 +166,7 @@ #define I801_BYTE 0x04 #define I801_BYTE_DATA 0x08 #define I801_WORD_DATA 0x0C -#define I801_PROC_CALL 0x10 /* unimplemented */ +#define I801_PROC_CALL 0x10 #define I801_BLOCK_DATA 0x14 #define I801_I2C_BLOCK_DATA 0x18 /* ICH5 and later */ #define I801_BLOCK_PROC_CALL 0x1C @@ -838,6 +838,14 @@ static s32 i801_access(struct i2c_adapte } xact = I801_WORD_DATA; break; + case I2C_SMBUS_PROC_CALL: + outb_p((addr & 0x7f) << 1, SMBHSTADD(priv)); + outb_p(command, SMBHSTCMD(priv)); + outb_p(data->word & 0xff, SMBHSTDAT0(priv)); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv)); + xact = I801_PROC_CALL; + read_write = I2C_SMBUS_READ; + break; case I2C_SMBUS_BLOCK_DATA: outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), SMBHSTADD(priv)); @@ -910,6 +918,7 @@ static s32 i801_access(struct i2c_adapte data->byte = inb_p(SMBHSTDAT0(priv)); break; case I801_WORD_DATA: + case I801_PROC_CALL: data->word = inb_p(SMBHSTDAT0(priv)) + (inb_p(SMBHSTDAT1(priv)) << 8); break; @@ -935,6 +944,7 @@ static u32 i801_func(struct i2c_adapter return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK | ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) | ((priv->features & FEATURE_BLOCK_PROC) ? -- Jean Delvare SUSE L3 Support
