From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Sverdlin Subject: Re: [PATCH] i2c: tegra: apply size limit quirk Date: Wed, 17 Jun 2015 16:33:40 +0200 Message-ID: <55818544.2020000@nokia.com> References: <1434477449-8340-1-git-send-email-wsa@the-dreams.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1434477449-8340-1-git-send-email-wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: ext Wolfram Sang , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Hi! On 16/06/15 19:57, ext Wolfram Sang wrote: > payload_size is a 12 bit field in the HW register, so add a limit for > this size. That way we gracefully reject the message beforehand instead > of generating an OOPS while transferring. Verified using some older > Tegra2 documentation and a more recent Jetson TK1 board. > > Signed-off-by: Wolfram Sang Looks good, Reviewed-by: Alexander Sverdlin > --- > drivers/i2c/busses/i2c-tegra.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c > index 0a1b6eacef0fba..78a36681469674 100644 > --- a/drivers/i2c/busses/i2c-tegra.c > +++ b/drivers/i2c/busses/i2c-tegra.c > @@ -669,6 +669,12 @@ static const struct i2c_algorithm tegra_i2c_algo = { > .functionality = tegra_i2c_func, > }; > > +/* payload size is only 12 bit */ > +static struct i2c_adapter_quirks tegra_i2c_quirks = { > + .max_read_len = 4096, > + .max_write_len = 4096, > +}; > + > static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { > .has_continue_xfer_support = false, > .has_per_pkt_xfer_complete_irq = false, > @@ -739,6 +745,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) > i2c_dev->base = base; > i2c_dev->div_clk = div_clk; > i2c_dev->adapter.algo = &tegra_i2c_algo; > + i2c_dev->adapter.quirks = &tegra_i2c_quirks; > i2c_dev->irq = irq; > i2c_dev->cont_id = pdev->id; > i2c_dev->dev = &pdev->dev; -- Best regards, Alexander Sverdlin.