From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eduardo Valentin Subject: Re: [PATCH 03/17] Input: sun4i-ts: Add thermal zone sensor support Date: Fri, 9 Jan 2015 14:07:44 -0400 Message-ID: <20150109180742.GB9510@developer> References: <1420511727-8242-1-git-send-email-wens@csie.org> <1420511727-8242-4-git-send-email-wens@csie.org> <20150106152425.GA6276@developer> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="aVD9QWMuhilNxW9f" Return-path: Received: from mail-qa0-f42.google.com ([209.85.216.42]:59153 "EHLO mail-qa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752305AbbAISHz (ORCPT ); Fri, 9 Jan 2015 13:07:55 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Chen-Yu Tsai Cc: Maxime Ripard , Dmitry Torokhov , Zhang Rui , Hans de Goede , "linux-input@vger.kernel.org" , linux-arm-kernel , linux-pm@vger.kernel.org --aVD9QWMuhilNxW9f Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 08, 2015 at 09:33:54PM +0800, Chen-Yu Tsai wrote: > On Thu, Jan 8, 2015 at 12:24 AM, Chen-Yu Tsai wrote: > > Hi, > > > > On Tue, Jan 6, 2015 at 11:24 PM, Eduardo Valentin = wrote: > >> Hello Chen-Yu, > >> > >> > >> On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote: > >>> The touchscreen controller has a temperature sensor embedded in the S= oC, > >>> which already has hwmon support in the driver. > >>> > >>> Add DT thermal zone support so we can use it with cpufreq for thermal > >>> throttling. > >>> > >>> Signed-off-by: Chen-Yu Tsai > >>> --- > >>> .../bindings/input/touchscreen/sun4i.txt | 1 + > >>> drivers/input/touchscreen/sun4i-ts.c | 27 ++++++++++++= ++++++++++ > >>> 2 files changed, 28 insertions(+) > >>> > >>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4= i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt > >>> index aef57791f40b..7f1110adbd24 100644 > >>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt > >>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt > >>> @@ -5,6 +5,7 @@ Required properties: > >>> - compatible: "allwinner,sun4i-a10-ts" > >>> - reg: mmio address range of the chip > >>> - interrupts: interrupt to which the chip is connected > >>> + - #thermal-sensor-cells: shall be 0 > >>> > >> > >> You may want to update your Example section too, below. > >> Example: > >> > >> rtp: rtp@01c25000 { > >> compatible =3D "allwinner,sun4i-a10-ts"; > >> reg =3D <0x01c25000 0x100>; > >> interrupts =3D <29>; > >> allwinner,ts-attached; > >> #thermal-sensor-cells =3D <0>; > >> }; > > > > Ok. > > > >> > >> > >>> Optional properties: > >>> - allwinner,ts-attached: boolean indicating that an actual touchscr= een is > >>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/tou= chscreen/sun4i-ts.c > >>> index 28a06749ae42..b6e9043446d6 100644 > >>> --- a/drivers/input/touchscreen/sun4i-ts.c > >>> +++ b/drivers/input/touchscreen/sun4i-ts.c > >>> @@ -34,6 +34,7 @@ > >>> > >>> #include > >>> #include > >>> +#include > >>> #include > >>> #include > >>> #include > >>> @@ -107,6 +108,7 @@ > >>> struct sun4i_ts_data { > >>> struct device *dev; > >>> struct input_dev *input; > >>> + struct thermal_zone_device *tz; > >>> void __iomem *base; > >>> unsigned int irq; > >>> bool ignore_fifo_data; > >>> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev) > >>> writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); > >>> } > >>> > >>> +static int get_temp(void *data, long *temp) > >>> +{ > >>> + struct sun4i_ts_data *ts =3D data; > >>> + > >>> + /* No temp_data until the first irq */ > >>> + if (ts->temp_data =3D=3D -1) > >>> + return -EAGAIN; > >>> + > >>> + *temp =3D (ts->temp_data - 1447) * 100; > >>> + > >> > >> Care to explain the formula in a simple comment? > > > > This was just copied from the hwmon section. AFAIK there is no document= ation > > for the formula. It was probably copied from Allwinner's SDK code. > > > > Hans? Do you remember where you got this? >=20 > So this is from the AXP209 datasheet. The Allwinner SoC datasheets don't > mention the formula to calculate the temperature. But since Allwinner > and X-powers are affiliated, it's possible they use the same formula. >=20 > http://comments.gmane.org/gmane.comp.hardware.netbook.arm.sunxi/3838 Ok. We use in the thermal framework miliCelsius as the temperature unit. Can you make sure the resulting temperature is in miliCelsius? Cheers, >=20 > >>> + return 0; > >>> +} > >>> + > >>> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops =3D { > >>> + .get_temp =3D get_temp, > >>> +}; > >>> + > >>> static ssize_t show_temp(struct device *dev, struct device_attribute= *devattr, > >>> char *buf) > >>> { > >>> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device= *pdev) > >>> if (IS_ERR(hwmon)) > >>> return PTR_ERR(hwmon); > >>> > >>> + ts->tz =3D thermal_zone_of_sensor_register(ts->dev, 0, ts, > >>> + &sun4i_ts_tz_ops); > >>> + if (IS_ERR(ts->tz)) > >>> + ts->tz =3D NULL; > >>> + > >>> writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); > >>> > >>> if (ts_attached) { > >> > >> here.. if input_register_device fails, you will keep an orphan thermal= zone > >> registered in your system: > >> > >> error =3D input_register_device(ts->input); > >> if (error) { > >> writel(0, ts->base + TP_INT_FIFOC); > > > > Will add an unregister call here. > > > > > > Thanks for the review. > > > > ChenYu > > > >> return error; > >> } > >> ... > >> > >> > >>> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device= *pdev) > >>> if (ts->input) > >>> input_unregister_device(ts->input); > >>> > >>> + if (ts->tz) > >>> + thermal_zone_of_sensor_unregister(ts->dev, ts->tz); > >>> + > >>> /* Deactivate all IRQs */ > >>> writel(0, ts->base + TP_INT_FIFOC); > >>> > >>> -- > >>> 2.1.4 > >>> --aVD9QWMuhilNxW9f Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBAgAGBQJUsBjlAAoJEMLUO4d9pOJWCfkIAIXJ0C9BfPxl39tC1xaJRfSZ VZh7BG4rclVRCwsCjMR6cjWnoL+9M/Goryy+/yxUZlwwczUNc0Af46tbJ3mosI4l c53ecdaf37hsNL5C46f5LDoFL2RmRD6HimHQO07qOkdwh8krt61NtmgtUlmMRjEd kkGUqKwcmjzAHue7EFow6B7QxcWKJzDhtPTDIyTbkQ2N+KLjIwNs3SDJEd8lVvIa Oo0ijdY05ont1g3Y7l3Kq+iyRz7aP4B8YM1J/j+OJfGoK+jnRvy8cB6AQSdVUsZg hJyv5M9jTB8Wz/Hj4UJ/bnNcBHhcbcQ73z7Y5Ld9Xdqan6fqdEpyZCslY3kza3E= =qCIs -----END PGP SIGNATURE----- --aVD9QWMuhilNxW9f--