From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: Re: [PATCH v2] pwm: lpss: Make builtin so that i915 can find the pwm_backlight Date: Fri, 20 Jan 2017 08:03:33 +0100 Message-ID: <20170120070333.GD4894@ulmo.ba.sec> References: <20170119175830.3754-1-hdegoede@redhat.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0619500208==" Return-path: Received: from mail-wm0-x242.google.com (mail-wm0-x242.google.com [IPv6:2a00:1450:400c:c09::242]) by gabe.freedesktop.org (Postfix) with ESMTPS id C06DA6EB16 for ; Fri, 20 Jan 2017 07:03:37 +0000 (UTC) Received: by mail-wm0-x242.google.com with SMTP id c85so4436703wmi.1 for ; Thu, 19 Jan 2017 23:03:37 -0800 (PST) In-Reply-To: <20170119175830.3754-1-hdegoede@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Hans de Goede Cc: linux-pwm@vger.kernel.org, intel-gfx , Andy Shevchenko , Mika Westerberg List-Id: intel-gfx@lists.freedesktop.org --===============0619500208== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="hoZxPH4CaxYzWscb" Content-Disposition: inline --hoZxPH4CaxYzWscb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 19, 2017 at 06:58:30PM +0100, Hans de Goede wrote: > The primary consumer of the lpss pwm is the i915 kms driver, > the i915 driver does not support get_pwm returning -EPROBE_DEFER and > its init is very complex making this is almost impossible to fix. >=20 > This commit changes the PWM_LPSS Kconfig from a tristate to a bool, so > that when the i915 driver loads the lpss pwm will be available avoiding > the -EPROBE_DEFER issue. Note that this is identical to how the same > problem was solved for the pwm-crc driver, which is used by the i915 > driver on other platforms. >=20 > Signed-off-by: Hans de Goede > Acked-by: Jani Nikula > --- > Changes in v2: > -Drop the pwm_add_table call (this has been moved to the acpi_lpss driver) > --- > drivers/pwm/Kconfig | 12 +++--------- > 1 file changed, 3 insertions(+), 9 deletions(-) For the record I think this is completely wrong and i915 should be taught how to deal with -EPROBE_DEFER. We've gone through a lot of pain to clean up this kind of init-level ordering on other devices and the result is, in my opinion, a *lot* better than what we had before. It'd be shame to see i915 backpedal on that. That said, if everyone else thinks that it really can't be done and this workaround is the best way forward, I'll just shut up about it and stop caring. Mika, Andy, any objections to this? Thierry --hoZxPH4CaxYzWscb Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAliBtkMACgkQ3SOs138+ s6EnDw//fQwLynafw2cvXzsF5UC+iK6vaCXKSddQVqe12gcZnp0bWR3HRhC+wNbN rdpRyYrhWsRLFL12kr9VMccxn4MVuARpHlJv342pTrU5CbtNC7h8d9Ctj+bKqp+q ALT7XO6evpyZH8tNIcV3beBCm+hwiAKNa2uZ52nISYu4ztECaMKwKjxPH7893N0l 9jBy+7nP2tMlkwFrALIU0JnZLKN9+HhxbW35s39t1jMNJ8zcUIvT+37F1VY/XRwm Kp1ixQlWV2nJjfxnPyl9mFtpdnBEfXDXN8QgjiDXTKQdhhROmtciwFFsPGNCutGn LYuPUwDY+/VZyyA22LGb7CTsYdUYUuAPvJeq7USBcTgYJJNvX4S+J3tF2rP4PQ1g RV4f1ZsXbfCxAE3xH56tvLOe7zSRpthv8oJjA3Soq4ZHY0p7hGO0p97Z/yXFv6rP PB0pcOELJygwfWF2b6QWEdJ1AGJr0zJdFtW560t8cVXYlNaMVNxzXbb4qZsEZZ3l zF3riiPJ0IxKfOs8o3AZuY1h/sTqgQrtTyGsHzvf0NNjWtSbw3Vbj0obbTUpJlld ovszma4cjlDs6SmowmdJKztNE5sFezDb98N3VReUDdWe02Ll+gihlEjuUVmKmm1I d9tGOrM3j3crqqQLaSH/cpvkXRwLUe+2+mIGbbXFnoKMDmv4CjM= =aeUO -----END PGP SIGNATURE----- --hoZxPH4CaxYzWscb-- --===============0619500208== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4 IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4Cg== --===============0619500208==--