On Thu, Jan 28, 2021 at 10:42:54AM +0100, Geert Uytterhoeven wrote:
Hi Kari,
On Thu, Jan 28, 2021 at 7:53 AM Kari Argillander kari.argillander@gmail.com wrote:
On Thu, Jan 28, 2021 at 09:42:58AM +0800, carlis wrote:
On Thu, 28 Jan 2021 00:32:22 +0200 Kari Argillander kari.argillander@gmail.com wrote:
@@ -82,6 +111,33 @@ enum st7789v_command { */ static int init_display(struct fbtft_par *par) {
- int rc;
- struct device *dev = par->info->device;
- par->gpio.te = devm_gpiod_get_index_optional(dev, "te", 0,
GPIOD_IN);
- if (IS_ERR(par->gpio.te)) {
rc = PTR_ERR(par->gpio.te);dev_err(par->info->device, "Failed to request tegpio: %d\n", rc);
return rc;- }
You request with optinal and you still want to error out? We could just continue and not care about that error. User will be happier if device still works somehow.
devm_gpiod_get_index_optional() returns NULL, not an error, if the GPIO is not found. So if IS_ERR() is the right check.
And checks for -EPROBE_DEFER can be handled automatically by using dev_err_probe() instead of dev_err().
Yeah. Thanks for pointing that clearly.
You mean i just delete this dev_err print ?! like this: par->gpio.te = devm_gpiod_get_index_optional(dev, "te", 0,GPIOD_IN); if (IS_ERR(par->gpio.te)) return PTR_ERR(par->gpio.te);
Not exactly. I'm suggesting something like this.
if (IS_ERR(par->gpio.te) == -EPROBE_DEFER) { return -EPROBE_DEFER;
if (IS_ERR(par->gpio.te)) par-gpio.te = NULL;
This like beginning of your patch series but the difference is that if EPROBE_DEFER then we will try again later. Any other error and we will just ignore TE gpio. But this is up to you what you want to do. To me this just seems place where this kind of logic can work.