diff options
| -rw-r--r-- | Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt | 36 | ||||
| -rw-r--r-- | arch/arm/boot/dts/imx28-evk.dts | 4 | ||||
| -rw-r--r-- | drivers/staging/iio/adc/mxs-lradc.c | 57 |
3 files changed, 71 insertions, 26 deletions
diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt index 46882058b59b..ee05dc390694 100644 --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt @@ -1,7 +1,8 @@ * Freescale i.MX28 LRADC device driver Required properties: -- compatible: Should be "fsl,imx28-lradc" +- compatible: Should be "fsl,imx23-lradc" for i.MX23 SoC and "fsl,imx28-lradc" + for i.MX28 SoC - reg: Address and length of the register set for the device - interrupts: Should contain the LRADC interrupts @@ -9,13 +10,38 @@ Optional properties: - fsl,lradc-touchscreen-wires: Number of wires used to connect the touchscreen to LRADC. Valid value is either 4 or 5. If this property is not present, then the touchscreen is - disabled. + disabled. 5 wires is valid for i.MX28 SoC only. +- fsl,ave-ctrl: number of samples per direction to calculate an average value. + Allowed value is 1 ... 31, default is 4 +- fsl,ave-delay: delay between consecutive samples. Allowed value is + 1 ... 2047. It is used if 'fsl,ave-ctrl' > 1, counts at + 2 kHz and its default is 2 (= 1 ms) +- fsl,settling: delay between plate switch to next sample. Allowed value is + 1 ... 2047. It counts at 2 kHz and its default is + 10 (= 5 ms) -Examples: +Example for i.MX23 SoC: + + lradc@80050000 { + compatible = "fsl,imx23-lradc"; + reg = <0x80050000 0x2000>; + interrupts = <36 37 38 39 40 41 42 43 44>; + status = "okay"; + fsl,lradc-touchscreen-wires = <4>; + fsl,ave-ctrl = <4>; + fsl,ave-delay = <2>; + fsl,settling = <10>; + }; + +Example for i.MX28 SoC: lradc@80050000 { compatible = "fsl,imx28-lradc"; reg = <0x80050000 0x2000>; - interrupts = <10 14 15 16 17 18 19 - 20 21 22 23 24 25>; + interrupts = <10 14 15 16 17 18 19 20 21 22 23 24 25>; + status = "okay"; + fsl,lradc-touchscreen-wires = <5>; + fsl,ave-ctrl = <4>; + fsl,ave-delay = <2>; + fsl,settling = <10>; }; diff --git a/arch/arm/boot/dts/imx28-evk.dts b/arch/arm/boot/dts/imx28-evk.dts index 15715d921d14..aa33393903a8 100644 --- a/arch/arm/boot/dts/imx28-evk.dts +++ b/arch/arm/boot/dts/imx28-evk.dts @@ -183,6 +183,10 @@ lradc@80050000 { status = "okay"; + fsl,lradc-touchscreen-wires = <4>; + fsl,ave-ctrl = <4>; + fsl,ave-delay = <2>; + fsl,settling = <10>; }; i2c0: i2c@80058000 { diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c index 18510d1ea5c8..dfd1bc1cc56f 100644 --- a/drivers/staging/iio/adc/mxs-lradc.c +++ b/drivers/staging/iio/adc/mxs-lradc.c @@ -1224,10 +1224,45 @@ MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids); static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, struct device_node *lradc_node) { - /* TODO retrieve from device tree */ + int ret; + u32 ts_wires = 0, adapt; + + ret = of_property_read_u32(lradc_node, "fsl,lradc-touchscreen-wires", + &ts_wires); + if (ret) + return -ENODEV; /* touchscreen feature disabled */ + + switch (ts_wires) { + case 4: + lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE; + break; + case 5: + if (lradc->soc == IMX28_LRADC) { + lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_5WIRE; + break; + } + /* fall through an error message for i.MX23 */ + default: + dev_err(lradc->dev, + "Unsupported number of touchscreen wires (%d)\n", + ts_wires); + return -EINVAL; + } + lradc->over_sample_cnt = 4; + ret = of_property_read_u32(lradc_node, "fsl,ave-ctrl", &adapt); + if (ret == 0) + lradc->over_sample_cnt = adapt; + lradc->over_sample_delay = 2; + ret = of_property_read_u32(lradc_node, "fsl,ave-delay", &adapt); + if (ret == 0) + lradc->over_sample_delay = adapt; + lradc->settling_delay = 10; + ret = of_property_read_u32(lradc_node, "fsl,settling", &adapt); + if (ret == 0) + lradc->settling_delay = adapt; return 0; } @@ -1243,7 +1278,6 @@ static int mxs_lradc_probe(struct platform_device *pdev) struct mxs_lradc *lradc; struct iio_dev *iio; struct resource *iores; - uint32_t ts_wires = 0; int ret = 0, touch_ret; int i; @@ -1277,25 +1311,6 @@ static int mxs_lradc_probe(struct platform_device *pdev) touch_ret = mxs_lradc_probe_touchscreen(lradc, node); - /* Check if touchscreen is enabled in DT. */ - ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires", - &ts_wires); - if (ret) - dev_info(dev, "Touchscreen not enabled.\n"); - else if (ts_wires == 4) - lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE; - else if (ts_wires == 5) - lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_5WIRE; - else - dev_warn(dev, "Unsupported number of touchscreen wires (%d)\n", - ts_wires); - - if ((lradc->soc == IMX23_LRADC) && (ts_wires == 5)) { - dev_warn(dev, "No support for 5 wire touches on i.MX23\n"); - dev_warn(dev, "Falling back to 4 wire\n"); - ts_wires = 4; - } - /* Grab all IRQ sources */ for (i = 0; i < of_cfg->irq_count; i++) { lradc->irq[i] = platform_get_irq(pdev, i); |