From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: Re: [PATCH 1/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve Date: Mon, 09 Mar 2015 09:15:47 +0100 Message-ID: <54FD56B3.7030200@redhat.com> References: <1425848022-18001-1-git-send-email-hdegoede@redhat.com> <1425848022-18001-2-git-send-email-hdegoede@redhat.com> <20150308211335.GB23193@dtor-ws> Reply-To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Return-path: In-Reply-To: <20150308211335.GB23193@dtor-ws> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Dmitry Torokhov Cc: Maxime Ripard , Chen-Yu Tsai , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree , linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Tong Zhang , Olliver Schinagl List-Id: devicetree@vger.kernel.org Hi, On 08-03-15 22:13, Dmitry Torokhov wrote: > On Sun, Mar 08, 2015 at 09:53:40PM +0100, Hans de Goede wrote: >> Testing has revealed that the temperature in the rtp controller of the A10 >> (sun4i) SoC has a different curve then on the A13 (sun5i) and later models. >> >> Add a new sun5i-a13-ts compatible to differentiate the newer models and >> set the curve based on the compatible string. >> >> The new curve is still not ideal on all A10-s, that seems to have to >> do with there being a large spread between different A10-s out there, >> the new curve us based on callibration results on 4 completely different >> models: >> raw min raw max temp min temp max stepsize offset >> Tong Zhang's hackberry 2402 2680 45.0 80.0 0.125 -255.3 >> Hansg's Cubieboard 2207 2300 36.0 45.0 0.096 -175.8 >> Olliver's lime 1 (*): 2258 2537 48.3 87.1 0.139 -265.7 >> Olliver's lime 2 (*): 2222 2486 46.7 91.7 0.170 -331.0 >> *) from: http://linux-sunxi.org/Temperature_Calibration >> >> Average all 4: 0.133 -257.0 >> Average without outliers (middle 2): 0.132 -261.0 >> >> Since it is better to slightly overreport the temperature this patch uses >> the average of all 4 as curve. >> >> This fixes the temperature reported on the A10 being much higher then >> expected. >> >> Cc: Tong Zhang >> Cc: Olliver Schinagl >> Reported-by: Tong Zhang >> Signed-off-by: Hans de Goede > > > Applied, thank you. Thanks. Note I've just found out that I've made a math error, the offset as I've used it is in degrees, but the actual code applies the offset before multiplying by stepsize :| Given that this is rather backwards (every math course ever thought applies the multiplication before the offset for linear functions. I'll do a follow up patch fixing the code to do the logical thing, and adjusting the offset for the other models accordingly. Regards, Hans > >> --- >> .../devicetree/bindings/input/touchscreen/sun4i.txt | 3 ++- >> drivers/input/touchscreen/sun4i-ts.c | 16 +++++++++++++--- >> 2 files changed, 15 insertions(+), 4 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt >> index 433332d..d59d252 100644 >> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt >> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt >> @@ -2,7 +2,8 @@ sun4i resistive touchscreen controller >> -------------------------------------- >> >> Required properties: >> - - compatible: "allwinner,sun4i-a10-ts" or "allwinner,sun6i-a31-ts" >> + - compatible: "allwinner,sun4i-a10-ts", "allwinner,sun5i-a13-ts" or >> + "allwinner,sun6i-a31-ts" >> - reg: mmio address range of the chip >> - interrupts: interrupt to which the chip is connected >> - #thermal-sensor-cells: shall be 0 >> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c >> index b93a28b..66ccd5a 100644 >> --- a/drivers/input/touchscreen/sun4i-ts.c >> +++ b/drivers/input/touchscreen/sun4i-ts.c >> @@ -258,6 +258,15 @@ static int sun4i_ts_probe(struct platform_device *pdev) >> /* Allwinner SDK has temperature = -271 + (value / 6) (C) */ >> ts->temp_offset = 1626; >> ts->temp_step = 167; >> + } else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) { >> + /* >> + * The A10 temperature sensor has quite a wide spread, these >> + * parameters are based on the averaging of the calibration >> + * results of 4 completely different boards, with a spread of >> + * temp_step from 96 - 170 and temp_offset from 1758 - 3310. >> + */ >> + ts->temp_offset = 2570; >> + ts->temp_step = 133; >> } else { >> /* >> * The user manuals do not contain the formula for calculating >> @@ -330,10 +339,10 @@ static int sun4i_ts_probe(struct platform_device *pdev) >> * finally enable tp mode. >> */ >> reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1); >> - if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) >> - reg |= TP_MODE_EN(1); >> - else >> + if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) >> reg |= SUN6I_TP_MODE_EN(1); >> + else >> + reg |= TP_MODE_EN(1); >> writel(reg, ts->base + TP_CTRL1); >> >> /* >> @@ -383,6 +392,7 @@ static int sun4i_ts_remove(struct platform_device *pdev) >> >> static const struct of_device_id sun4i_ts_of_match[] = { >> { .compatible = "allwinner,sun4i-a10-ts", }, >> + { .compatible = "allwinner,sun5i-a13-ts", }, >> { .compatible = "allwinner,sun6i-a31-ts", }, >> { /* sentinel */ } >> }; >> -- >> 2.3.1 >> >