Re: [PATCH v5] i2c: designware: Currently if the SoC needs pinctrl to switch the SCL and SDA from the I2C function to GPI

Yann Sionneau
2023-08-22T14:26:38Z

Subject seems to have been truncated... I'll re-send.

On 8/22/23 16:25, Yann Sionneau wrote:
> scl-gpio = <>;
> sda-gpio = <>;
>
> Are not enough for some SoCs to have a working recovery.
> Some need:
>
> scl-gpio = <>;
> sda-gpio = <>;
> pinctrl-names = "default", "recovery";
> pinctrl-0 = <&i2c_pins_hw>;
> pinctrl-1 = <&i2c_pins_gpio>;
>
> The driver was not filling rinfo->pinctrl with the device node
> pinctrl data which is needed by generic recovery code.
>
> Signed-off-by: Yann Sionneau <ysionneau@kalray.eu>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> V4 -> V5:
> * put back `else if`
> * reword the commit msg Subject to add the `i2c: designware: ` tag
> * Add the missing `Reviewed-by: Andy Shevchenko` tag
>
> V3 -> V4:
> * Replace `else if` by simply `if`.
>
> V2 -> V3:
> * put back 'if (!rinfo->pinctrl)' test since devm_pinctrl_get()
> can return NULL if CONFIG_PINCTRL is not set.
> * print an error msg when devm_pinctrl_get() returns an error that
> is not -EPROBE_DEFER.
> * print a dbg msg if devm_pinctrl_get() return NULL.
>
> V1 -> V2:
> * remove the unnecessary 'if (!rinfo->pinctrl)' test
> * test if return is -EPROBE_DEFER, in that case, return it.
> * Reword the commit message according to review
>
> drivers/i2c/busses/i2c-designware-master.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
> index b720fcc5c10a..30b2de829a32 100644
> --- a/drivers/i2c/busses/i2c-designware-master.c
> +++ b/drivers/i2c/busses/i2c-designware-master.c
> @@ -17,6 +17,7 @@
> #include <linux/interrupt.h>
> #include <linux/io.h>
> #include <linux/module.h>
> +#include <linux/pinctrl/consumer.h>
> #include <linux/pm_runtime.h>
> #include <linux/regmap.h>
> #include <linux/reset.h>
> @@ -855,6 +856,17 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
> return PTR_ERR(gpio);
> rinfo->sda_gpiod = gpio;
>
> + rinfo->pinctrl = devm_pinctrl_get(dev->dev);
> + if (IS_ERR(rinfo->pinctrl)) {
> + if (PTR_ERR(rinfo->pinctrl) == -EPROBE_DEFER)
> + return PTR_ERR(rinfo->pinctrl);
> +
> + rinfo->pinctrl = NULL;
> + dev_err(dev->dev, "getting pinctrl info failed: bus recovery might not work\n");
> + } else if (!rinfo->pinctrl) {
> + dev_dbg(dev->dev, "pinctrl is disabled, bus recovery might not work\n");
> + }
> +
> rinfo->recover_bus = i2c_generic_scl_recovery;
> rinfo->prepare_recovery = i2c_dw_prepare_recovery;
> rinfo->unprepare_recovery = i2c_dw_unprepare_recovery;