On Sunday, May 20, 2018 4:44:31 PM CEST Andy Shevchenko wrote:
On Sun, May 20, 2018 at 12:55 AM, Janusz Krzysztofik
jmkrzyszt@gmail.com wrote:
On Saturday, May 19, 2018 8:00:38 PM CEST Andy Shevchenko wrote:
On Sat, May 19, 2018 at 2:15 AM, Janusz Krzysztofik jmkrzyszt@gmail.com
wrote:
NULL check in practice discards the _optional part of gpiod_get(). So, either you use non-optional variant and decide how to handle an errors, or user _optional w/o NULL check.
OK, I'm going to use something like the below while submitting v2:
gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN);if (!IS_ERR_OR_NULL(gpiod_rdy)) {this->dev_ready = ams_delta_nand_ready;} else {this->dev_ready = NULL;pr_notice("Couldn't request gpio for Delta NANDready.\n");
priv->gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy",GPIOD_IN);if (IS_ERR(priv->gpiod_rdy)) {err = PTR_ERR(priv->gpiod_nwp);dev_warn(&pdev->dev, "RDY GPIO request failed (%d)\n",err); + goto err_gpiod;
}
if (priv->gpiod_rdy)this->dev_ready = ams_delta_nand_ready;This makes sense.
Though, I completely dislike "rdy" name of GPIO. Where is it documented?
No documentation files for Amstrad Delta nor for its NAND driver specifically exist under Documentation/. However, there exist some for generic GPIO NAND driver where the pin name "rdy" is used explicitly: Documentation/driver-api/gpio/drivers-on-gpio.rst Documentation/devicetree/bindings/mtd/gpio-control-nand.txt You can find that mnemonic used across drivers/mtd/nand/, standalone or as a suffix, including the Amstrad Delta NAND driver before the change discussed.
To be honest, I don't like it much either, but I'm just using it instead of inventing something new.
Thanks, Janusz