From mboxrd@z Thu Jan 1 00:00:00 1970 From: Javier Martinez Canillas Subject: Re: [PATCH v2 1/2] ARM: OMAP2+: only search for GPMC DT child nodes on probe Date: Thu, 18 Apr 2013 00:10:16 +0200 Message-ID: <516F1DC8.2000707@collabora.co.uk> References: <1366230852-2440-1-git-send-email-javier.martinez@collabora.co.uk> <516F13B8.20601@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <516F13B8.20601@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Jon Hunter Cc: Tony Lindgren , Enric Balletbo i Serra , Lars Poeschel , devicetree-discuss@lists.ozlabs.org, linux-omap List-Id: devicetree@vger.kernel.org On 04/17/2013 11:27 PM, Jon Hunter wrote: > > On 04/17/2013 03:34 PM, Javier Martinez Canillas wrote: >> The GPMC DT probe function use for_each_node_by_name() to search >> child device nodes of the GPMC controller. But this function does >> not use the GPMC device node as the root of the search and instead >> search across the complete Device Tree. >> >> This means that any device node on the DT that is using any of the >> GPMC child nodes names searched for will be returned even if they >> are not connected to the GPMC, making the gpmc_probe_xxx_child() >> function to fail. >> >> Fix this by using the GPMC device node as the search root so the >> search will be restricted to its children. >> >> Reported-by: Lars Poeschel >> Signed-off-by: Javier Martinez Canillas >> --- >> >> Changes since v1 (suggested by Jon Hunter): >> - Split the search for GPMC child nodes and only warn if a >> child probe fails on two different patches >> - Don't probe all childs unnecesary if a previous matched >> >> arch/arm/mach-omap2/gpmc.c | 33 ++++++++++----------------------- >> 1 files changed, 10 insertions(+), 23 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c >> index ed946df..6166847 100644 >> --- a/arch/arm/mach-omap2/gpmc.c >> +++ b/arch/arm/mach-omap2/gpmc.c >> @@ -1520,32 +1520,19 @@ static int gpmc_probe_dt(struct platform_device *pdev) >> return ret; >> } >> >> - for_each_node_by_name(child, "nand") { >> - ret = gpmc_probe_nand_child(pdev, child); >> - if (ret < 0) { >> - of_node_put(child); >> - return ret; >> - } >> - } >> + for_each_child_of_node(pdev->dev.of_node, child) { >> >> - for_each_node_by_name(child, "onenand") { >> - ret = gpmc_probe_onenand_child(pdev, child); >> - if (ret < 0) { >> - of_node_put(child); >> - return ret; >> - } >> - } >> + if (!child->name) >> + continue; >> >> - for_each_node_by_name(child, "nor") { >> - ret = gpmc_probe_generic_child(pdev, child); >> - if (ret < 0) { >> - of_node_put(child); >> - return ret; >> - } >> - } >> + if (of_node_cmp(child->name, "nand") == 0) >> + ret = gpmc_probe_nand_child(pdev, child); >> + else if (of_node_cmp(child->name, "onenand") == 0) >> + ret = gpmc_probe_onenand_child(pdev, child); >> + else if (of_node_cmp(child->name, "ethernet") == 0 || >> + of_node_cmp(child->name, "nor") == 0) >> + ret = gpmc_probe_generic_child(pdev, child); >> >> - for_each_node_by_name(child, "ethernet") { >> - ret = gpmc_probe_generic_child(pdev, child); >> if (ret < 0) { > > I think that we need to make sure that "ret" is initialised to 0 at the > beginning of the function. We should not have a case where the child Hi Jon, I didn't set ret to 0 at the beginning of the function since it is assigned the return value of a previous call to of_property_read_u32(). So ret should be 0 when execution reaches the for loop. > name does not match but who knows. Actually that raises another point, > should we have an "else" clause at the end that WARNs on > "unknown/unsupported child" device? > Actually I thought about it when I was writing that patch and then I decided to not add a WARN for that case since nothing really fail in that case. I mean if we want to check that a DT is well formed then I think we will need to add much more checks and I don't know if is worth it. But I don't have a strong opinion on this so if you want I can add it an send a v3. >> of_node_put(child); >> return ret; >> > > Otherwise looks great. > > Cheers > Jon > Best regards, Javier