From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Date: Thu, 04 Jul 2013 15:20:23 +0000 Subject: Re: [PATCH net-next v3 1/3] sh_eth: add support for gpio reset Message-Id: <4213921.CCv1lD9ftn@avalon> List-Id: References: <1372652695-16606-1-git-send-email-horms+renesas@verge.net.au> <51D19122.6030409@cogentembedded.com> <20130702052458.GA23507@verge.net.au> In-Reply-To: <20130702052458.GA23507@verge.net.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Simon Horman Cc: Sergei Shtylyov , netdev@vger.kernel.org, linux-sh@vger.kernel.org, Magnus Damm Hi Simon, On Tuesday 02 July 2013 14:25:00 Simon Horman wrote: > On Mon, Jul 01, 2013 at 06:24:34PM +0400, Sergei Shtylyov wrote: > > On 01-07-2013 8:24, Simon Horman wrote: > > >Allow reset using a GPIO. In order to use this set the following > > > > > >in the device's platform data: > > > needs_gpio_reset = 1 > > > reset_gpio = GPIO pin to use > > > > > >This patch is motivated by the lager board which uses the r8a7790 SoC > > >which has a GPIO pin to reset its sh_eth device. > > > > > >Signed-off-by: Simon Horman > > > > > >-- > > > > > >v2 > > >* First post > > >--- > > > > > > drivers/net/ethernet/renesas/sh_eth.c | 4 ++++ > > > include/linux/sh_eth.h | 3 +++ > > > 2 files changed, 7 insertions(+) > > > > > >diff --git a/drivers/net/ethernet/renesas/sh_eth.c > > >b/drivers/net/ethernet/renesas/sh_eth.c index 7732f11..0253f61 100644 > > >--- a/drivers/net/ethernet/renesas/sh_eth.c > > >+++ b/drivers/net/ethernet/renesas/sh_eth.c > > > > [...] > > > > >@@ -2652,6 +2653,9 @@ static int sh_eth_drv_probe(struct platform_device > > >*pdev)> > > > > ndev->features = NETIF_F_HW_VLAN_CTAG_FILTER; > > > > > > } > > > > > >+ if (pd->needs_gpio_reset) > > >+ gpio_request_one(pd->reset_gpio, GPIOF_OUT_INIT_HIGH, NULL); > > > > > Is reset signal active low or active high? Are you asserting or > > > > releasing it? > > Good point. > > I'm not sure that the documentation that I have is sufficient to answer > that. Empirically it seems that this change isn't strictly necessary, so > perhaps it would be best to drop it for now. GPIO 5-31 is connected to the active-low reset input of the KSZ8041 PHY. Wouldn't it make more sense to handle it in the PHY framework ? More work is then be needed. If the Lager boot loader configures the GPIO correctly I would thus drop this patch. -- Regards, Laurent Pinchart