Messages in this thread | | | Subject | Re: [PATCH v10 5/7] i2c: fsi: Add transfer implementation | From | Eddie James <> | Date | Wed, 27 Jun 2018 08:21:30 -0500 |
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On 06/25/2018 09:38 PM, Wolfram Sang wrote: > On Wed, Jun 13, 2018 at 02:36:17PM -0500, Eddie James wrote: >> Execute I2C transfers from the FSI-attached I2C master. Use polling >> instead of interrupts as we have no hardware IRQ over FSI. >> >> Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com> >> --- >> drivers/i2c/busses/i2c-fsi.c | 195 ++++++++++++++++++++++++++++++++++++++++++- >> 1 file changed, 193 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c >> index 4611a0b..8c0a6cb 100644 >> --- a/drivers/i2c/busses/i2c-fsi.c >> +++ b/drivers/i2c/busses/i2c-fsi.c >> @@ -155,6 +155,7 @@ struct fsi_i2c_port { >> struct i2c_adapter adapter; >> struct fsi_i2c_master *master; >> u16 port; >> + u16 xfrd; >> }; >> >> static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, >> @@ -230,6 +231,99 @@ static int fsi_i2c_set_port(struct fsi_i2c_port *port) >> return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy); >> } >> >> +static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg, >> + bool stop) >> +{ >> + struct fsi_i2c_master *i2c = port->master; >> + u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR; >> + >> + port->xfrd = 0; >> + >> + if (msg->flags & I2C_M_RD) >> + cmd |= I2C_CMD_READ; > Since you support MANGLING, I'd think you can easily support > I2C_M_REV_DIR_ADDR here, too?
Hm, I don't really understand the purpose of that flag. From the docs:
This toggles the Rd/Wr flag. That is, if you want to do a write, but need to emit an Rd instead of a Wr, or vice versa, you set this flag. For example: S Addr Rd [A] Data [A] Data [A] ... [A] Data [A] P
I don't think our hardware supports this type of operation.
Thanks, Eddie
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