Hi,
On Thu, Jun 10, 2021 at 3:39 PM Linus Walleij linus.walleij@linaro.org wrote:
On Fri, Jun 11, 2021 at 12:30 AM Doug Anderson dianders@chromium.org wrote:
mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, 0x0a);I would still prefer it if there was some type of error checking since SPI commands can fail and could potentially fail silently. What about at least this (untested):
#define db7430_dbi_cmd(_db, _cmd, _seq...) \ do { int _ret = mipi_dbi_command(_db->dbi, _cmd, _seq); if (_ret) dev_warn(_db->dev, "DBI cmd %d failed (%d)\n", _cmd, _ret); } while (0)
Then at least you know _something_ will show up in the logs if there's a transfer failure instead of silence?
If you truly don't want the error checking then I guess I won't insist, but it feels like the kind of thing that will bite someone eventually... In any case, I'm happy to add this now (especially since the DBI stuff is Acked now).
This looks more like something that should be done in mipi_dbi_command() in include/drm/drm_mipi_dbi.h which claims:
- Returns:
- Zero on success, negative error code on failure.
*/
But no it does not return anything:
#define mipi_dbi_command(dbi, cmd, seq...) \ ({ \ const u8 d[] = { seq }; \ mipi_dbi_command_stackbuf(dbi, cmd, d, ARRAY_SIZE(d)); \ })
I'll fix up the include and apply then we can think about what to do with mipi_dbi_command().
Are you sure that doesn't work? Isn't the return value of a macro the last expression? In this case the return value of mipi_dbi_command_stackbuf() should just flow through.
-Doug