From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH] spi: tegra114: add spi driver Date: Wed, 20 Feb 2013 13:11:12 +0000 Message-ID: <20130220131112.GE2726@opensource.wolfsonmicro.com> References: <1361281115-20436-1-git-send-email-ldewangan@nvidia.com> <5123C18A.9010604@wwwdotorg.org> <5124C18F.6070108@nvidia.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============8443615521534515653==" Cc: Stephen Warren , "linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org" To: Laxman Dewangan Return-path: In-Reply-To: <5124C18F.6070108-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" List-Id: linux-spi.vger.kernel.org --===============8443615521534515653== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ILuaRSyQpoVaJ1HG" Content-Disposition: inline --ILuaRSyQpoVaJ1HG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Feb 20, 2013 at 05:59:03PM +0530, Laxman Dewangan wrote: > On Tuesday 19 February 2013 11:46 PM, Stephen Warren wrote: > >In the older Tegra SPI drivers, the PM runtime logic was was of > >master->{un,}prepare_transfer. I'm curious why it's implemented > >differently here. > The prepare is called in atomic context and in this we are calling > pm_runtime_get_sync() which is blocking and it can cause issue. > I have already bug reported by you that sometimes you saw locking in > tegra20 slink driver which we need to fix. When testing this, I ran > into similar case and hence now moving this out or prepare. > I will push the change for fixing this in tegra20_slink driver also. As I think I've said before I keep thinking we ought to just have some basic runtime PM code in the core - a substantial proportion of drivers end up following the same pattern, it'd be surprising to see hardware that needed a different pattern. > >>+ tspi->clk = devm_clk_get(&pdev->dev, "spi"); > >Does this HW block use multiple clocks? If not, I think s/"spi"/NULL/ > >there, just like the Tegra20 driver. > No, spi controller uses the only one clock. I will change to NULL. I'm never convinced that NULL is a helpful clock name to pick, it's not awesome if you ever acquire a second clock. --ILuaRSyQpoVaJ1HG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJRJMtpAAoJELSic+t+oim9kBsQAJY+ECq8UzL+o+K4tOJd1dnm 3NpsTeMXCZeitEN2HKqTZxHsX/CBKP/59m9ZVQzoF49bH7bIsxOW1V+DE8xT6vmC JNQc+3yda9YdIzzBDwi+lQ29DfnxEUmLKlIwPIRnOpUzNPSTjQdJh7PgbwkAAIxW ivVMo4UdqKkzhj3db3eIrUNlFDFVfdZqBmn83hGN9A2+jB65E66btbeH+DprrEyY KsKGw4lX3xQ7XjdeAICraKlEXcdrmJ+zMsZSxHkZb6p2zWMnLknku0rDE4l9l192 CXgruSsyqiPEMo/SFSfKbbgE8Ls0qjFcyDzN18tCUuFnqLpXpxYlxFgHzGK5+1iy w1MCODkBzpJwxxq6dPPZ1+3QGQUqzYk2YCTJfJ195n2/DXXa46bsff6bozoJvXWM 7Hnhl16hWkAdeC2+2+Q6lWd9573sC/wccyhCe02HjiVEOnYpgrqmSVMn/EOC6dpG K6xpfhH2Qp+gveX/1QgJDkfW5QFWWyuPRf5CwEUduXgGhKDU5jrRpoU0///Tip9I EAzaBHRyXKklbXS6GkCUjIh1dwUiqgcU/j8iZOPSIz600n9hpBCLfZpgLwUF7pBb Nk1aofsSwgEh2HSESXQngQvItks4RSA9W326ysWcyhYlbauSC9N+a265aDG896ii 60M8Ex5wnO51wyr+DeKB =AR5w -----END PGP SIGNATURE----- --ILuaRSyQpoVaJ1HG-- --===============8443615521534515653== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ devicetree-discuss mailing list devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org https://lists.ozlabs.org/listinfo/devicetree-discuss --===============8443615521534515653==--