From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sam Povilus Subject: [PATCH] Adding the ability for the ads7828 and ads7830 to use the device tree to get thier optional parameters, instead of using platform devices. This allows people using custom boards to also use the ads7828 in a non-default manner. Date: Sat, 11 Mar 2017 20:22:52 -0700 Message-ID: <20170312032252.10656-1-kernel.development@povil.us> Return-path: Sender: linux-hwmon-owner@vger.kernel.org To: wsa@the-dreams.de, jdelvare@suse.com, linux@roeck-us.net, linux-hwmon@vger.kernel.org, linux-i2c@vger.kernel.org Cc: Sam Povilus List-Id: linux-i2c@vger.kernel.org Also adding a note to the user if they misconfigure the device's external reference. Signed-off-by: Sam Povilus --- Documentation/devicetree/bindings/hwmon/ads7828.txt | 18 ++++++++++++++++++ .../devicetree/bindings/i2c/trivial-devices.txt | 2 -- drivers/hwmon/ads7828.c | 21 +++++++++++++++++++++ 3 files changed, 39 insertions(+), 2 deletions(-) create mode 100644 Documentation/devicetree/bindings/hwmon/ads7828.txt diff --git a/Documentation/devicetree/bindings/hwmon/ads7828.txt b/Documentation/devicetree/bindings/hwmon/ads7828.txt new file mode 100644 index 000000000000..7cd786585b51 --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/ads7828.txt @@ -0,0 +1,18 @@ +ads7828 properties + +Required properties: +- compatible: + Should be one of + ti,ads7828 + ti,ads7830 +- reg: I2C address + +Optional properties: + +- diff_input + Set to use the device in differential mode. +- ext_vref + Set to enable the external voltage reference on the device. +- vref_mv + The external reference on the device is set to this as an unsigned integer in + milivolts. Must use "ext_vref" for this to have any meaning. diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt index cdd7b48826c3..87648909f6ce 100644 --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt @@ -163,8 +163,6 @@ st,m41t00 Serial real-time clock (RTC) st,m41t62 Serial real-time clock (RTC) with alarm st,m41t80 M41T80 - SERIAL ACCESS RTC WITH ALARMS taos,tsl2550 Ambient Light Sensor with SMBUS/Two Wire Serial Interface -ti,ads7828 8-Channels, 12-bit ADC -ti,ads7830 8-Channels, 8-bit ADC ti,tsc2003 I2C Touch-Screen Controller ti,tmp102 Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface ti,tmp103 Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index ee396ff167d9..1a6a91f3701f 100644 --- a/drivers/hwmon/ads7828.c +++ b/drivers/hwmon/ads7828.c @@ -118,6 +118,7 @@ static int ads7828_probe(struct i2c_client *client, struct ads7828_data *data; struct device *hwmon_dev; unsigned int vref_mv = ADS7828_INT_VREF_MV; + unsigned int vref_mv_tmp; bool diff_input = false; bool ext_vref = false; unsigned int regval; @@ -131,11 +132,31 @@ static int ads7828_probe(struct i2c_client *client, ext_vref = pdata->ext_vref; if (ext_vref && pdata->vref_mv) vref_mv = pdata->vref_mv; + } else if (dev->of_node) { + if(of_get_property(dev->of_node, "diff_input", NULL)) + { + diff_input = true; + } + if(of_get_property(dev->of_node, "ext_vref", NULL)) + { + ext_vref = true; + } + if(!of_property_read_u32(dev->of_node, "vref_mv", &vref_mv_tmp) + && ext_vref) { + vref_mv = vref_mv_tmp; + } } /* Bound Vref with min/max values */ + vref_mv_tmp = vref_mv; vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN, ADS7828_EXT_VREF_MV_MAX); + if(vref_mv_tmp != vref_mv) + { + pr_info("You used and invalid external vref," + " it has been clamped to %u", + vref_mv); + } /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */ if (id->driver_data == ads7828) { -- 2.11.0