On Tue, 2021-04-20 at 15:23 +0200, Michal Simek wrote:
> Hi,
>
> On 4/16/21 1:25 AM, Robert Hancock wrote:
> > Hook up the standard GPIO/pinctrl-based recovery support for this
> > driver.
> >
> > Based on a patch "i2c: cadence: Recover bus after controller reset" by
> > Chirag Parekh in the Xilinx kernel Git tree, but simplified to make use
> > of more common code.
> >
> > Cc: Chirag Parekh <chiragp@xxxxxxxxxx>
> > Signed-off-by: Robert Hancock <robert.hancock@xxxxxxxxxx>
> > ---
> > drivers/i2c/busses/i2c-cadence.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-
> > cadence.c
> > index c1bbc4caeb5c..d017bc64e759 100644
> > --- a/drivers/i2c/busses/i2c-cadence.c
> > +++ b/drivers/i2c/busses/i2c-cadence.c
> > @@ -178,6 +178,7 @@ enum cdns_i2c_slave_state {
> > * @clk: Pointer to struct clk
> > * @clk_rate_change_nb: Notifier block for clock rate changes
> > * @quirks: flag for broken hold bit usage in r1p10
> > + * @rinfo: Structure holding recovery information.
> > * @ctrl_reg_diva_divb: value of fields DIV_A and DIV_B from CR register
> > * @slave: Registered slave instance.
> > * @dev_mode: I2C operating role(master/slave).
> > @@ -202,6 +203,7 @@ struct cdns_i2c {
> > struct clk *clk;
> > struct notifier_block clk_rate_change_nb;
> > u32 quirks;
> > + struct i2c_bus_recovery_info rinfo;
> > #if IS_ENABLED(CONFIG_I2C_SLAVE)
> > u16 ctrl_reg_diva_divb;
> > struct i2c_client *slave;
> > @@ -752,6 +754,7 @@ static int cdns_i2c_process_msg(struct cdns_i2c *id,
> > struct i2c_msg *msg,
> > /* Wait for the signal of completion */
> > time_left = wait_for_completion_timeout(&id->xfer_done, adap->timeout);
> > if (time_left == 0) {
> > + i2c_recover_bus(adap);
> > cdns_i2c_master_reset(adap);
> > dev_err(id->adap.dev.parent,
> > "timeout waiting on completion\n");
> > @@ -1212,6 +1215,7 @@ static int cdns_i2c_probe(struct platform_device
> > *pdev)
> > id->adap.retries = 3; /* Default retry value. */
> > id->adap.algo_data = id;
> > id->adap.dev.parent = &pdev->dev;
> > + id->adap.bus_recovery_info = &id->rinfo;
> > init_completion(&id->xfer_done);
> > snprintf(id->adap.name, sizeof(id->adap.name),
> > "Cadence I2C at %08lx", (unsigned long)r_mem->start);
> >
>
> My colleague sent pinctrl driver for ZynqMP already. This driver can be
> used on Zynq where pinctrl driver already exists upstream.
>
> It looks quite nice.
>
> Acked-by: Michal Simek <michal.simek@xxxxxxxxxx>
>
Any other feedback on this patch? I only saw the ack from Michal. The pinctrl
driver which is needed to make this useful on the ZynqMP platform has now been
merged into mainline (commit 8b242ca700f8043be56542efd8360056358a42ed,
"pinctrl: Add Xilinx ZynqMP pinctrl driver support").
> Thanks,
> Michal
--
Robert Hancock
Senior Hardware Designer, Calian Advanced Technologies
www.calian.com
