Add device tree support for the I2C variant of AD7879 (AD7879-1). This allows to specify the touchscreen controller as a I2C client node. Most of the options available as platform data are also available as device tree properties. Exporting the GPIO is currently not possible through device tree. Signed-off-by: Stefan Agner <stefan@xxxxxxxx> --- .../bindings/input/touchscreen/ad7879-i2c.txt | 47 ++++++++++++++++ drivers/input/touchscreen/ad7879-i2c.c | 63 +++++++++++++++++++++- drivers/input/touchscreen/ad7879-spi.c | 3 +- drivers/input/touchscreen/ad7879.c | 2 +- drivers/input/touchscreen/ad7879.h | 1 + 5 files changed, 113 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/input/touchscreen/ad7879-i2c.txt diff --git a/Documentation/devicetree/bindings/input/touchscreen/ad7879-i2c.txt b/Documentation/devicetree/bindings/input/touchscreen/ad7879-i2c.txt new file mode 100644 index 0000000..bf169a2 --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/ad7879-i2c.txt @@ -0,0 +1,47 @@ +* Analog Devices AD7879-1/AD7889-1 touchscreen interface (I2C) + +Required properties: +- compatible: must be "adi,ad7879-1" +- reg: i2c slave address +- interrupt-parent: the phandle for the interrupt controller +- interrupts: touch controller interrupt +- resistance-plate-x : total resistance of X-plate (for pressure + calculation) +- touchscreen-max-pressure : maximum reported pressure +- touchscreen-swapped-x-y : X and Y axis are swapped (boolean) + Swapping is done after inverting the axis +Optional properties: +- first-conversion-delay : 0-12 in 128us steps (starting with 128us) + 13: 2.560ms + 14: 3.584ms + 15: 4.096ms +- acquisition-time : 0: 2us + 1: 4us + 2: 8us + 3: 16us +- median-filter-size : 0: disabled + 1: 4 measurements + 2: 8 measurements + 3: 16 measurements +- averaging : 0: 2 middle values (1 if median disabled) + 1: 4 middle values + 2: 8 middle values + 3: 16 values +- conversion-interval: : 0: convert one time only + 1-255: 515us + val * 35us (up to 9.440ms) + +Example: + + ad7879@2c { + compatible = "adi,ad7879-1"; + reg = <0x2c>; + interrupt-parent = <&gpio1>; + interrupts = <13 IRQ_TYPE_EDGE_FALLING>; + resistance-plate-x = <120>; + touchscreen-max-pressure = <4096>; + first-conversion-delay = /bits/ 8 <3>; + acquisition-time = /bits/ 8 <1>; + median-filter-size = /bits/ 8 <2>; + averaging = /bits/ 8 <1>; + conversion-interval = /bits/ 8 <255>; + }; diff --git a/drivers/input/touchscreen/ad7879-i2c.c b/drivers/input/touchscreen/ad7879-i2c.c index d66962c..08a2c9a 100644 --- a/drivers/input/touchscreen/ad7879-i2c.c +++ b/drivers/input/touchscreen/ad7879-i2c.c @@ -11,6 +11,7 @@ #include <linux/module.h> #include <linux/types.h> #include <linux/pm.h> +#include <linux/input/ad7879.h> #include "ad7879.h" @@ -54,9 +55,50 @@ static const struct ad7879_bus_ops ad7879_i2c_bus_ops = { .write = ad7879_i2c_write, }; +static struct ad7879_platform_data *ad7879_parse_dt(struct device *dev) +{ + struct ad7879_platform_data *pdata; + struct device_node *np = dev->of_node; + int err; + u32 tmp; + + if (!np) + return NULL; + + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); + + if (!pdata) + return ERR_PTR(-ENOMEM); + + err = of_property_read_u32(np, "resistance-plate-x", &tmp); + if (err) { + dev_err(dev, "failed to get resistance-plate-x property\n"); + return ERR_PTR(err); + } + pdata->x_plate_ohms = (u16)tmp; + + err = of_property_read_u32(np, "touchscreen-max-pressure", &tmp); + if (err) { + dev_err(dev, "failed to get touchscreen-max-pressure property\n"); + return ERR_PTR(err); + } + pdata->pressure_min = (u16)tmp; + + of_property_read_u8(np, "first-conversion-delay", &pdata->first_conversion_delay); + of_property_read_u8(np, "acquisition-time", &pdata->acquisition_time); + of_property_read_u8(np, "median-filter-size", &pdata->median); + of_property_read_u8(np, "averaging", &pdata->averaging); + of_property_read_u8(np, "conversion-interval", &pdata->pen_down_acc_interval); + + pdata->swap_xy = of_property_read_bool(np, "touchscreen-swapped-x-y"); + + return pdata; +} + static int ad7879_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id) { + struct ad7879_platform_data *pdata; struct ad7879 *ts; if (!i2c_check_functionality(client->adapter, @@ -65,7 +107,17 @@ static int ad7879_i2c_probe(struct i2c_client *client, return -EIO; } - ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq, + pdata = dev_get_platdata(&client->dev); + + if (!pdata && IS_ENABLED(CONFIG_OF)) + pdata = ad7879_parse_dt(&client->dev); + + if (IS_ERR_OR_NULL(pdata)) { + dev_err(&client->dev, "Need platform data\n"); + return PTR_ERR(pdata); + } + + ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq, pdata, &ad7879_i2c_bus_ops); if (IS_ERR(ts)) return PTR_ERR(ts); @@ -91,10 +143,19 @@ static const struct i2c_device_id ad7879_id[] = { }; MODULE_DEVICE_TABLE(i2c, ad7879_id); +#ifdef CONFIG_OF +static const struct of_device_id ad7879_dt_ids[] = { + { .compatible = "adi,ad7879-1", }, + { } +}; +MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids); +#endif + static struct i2c_driver ad7879_i2c_driver = { .driver = { .name = "ad7879", .pm = &ad7879_pm_ops, + .of_match_table = of_match_ptr(ad7879_dt_ids), }, .probe = ad7879_i2c_probe, .remove = ad7879_i2c_remove, diff --git a/drivers/input/touchscreen/ad7879-spi.c b/drivers/input/touchscreen/ad7879-spi.c index 48033c2..8ebe604 100644 --- a/drivers/input/touchscreen/ad7879-spi.c +++ b/drivers/input/touchscreen/ad7879-spi.c @@ -128,7 +128,8 @@ static int ad7879_spi_probe(struct spi_device *spi) return err; } - ts = ad7879_probe(&spi->dev, AD7879_DEVID, spi->irq, &ad7879_spi_bus_ops); + ts = ad7879_probe(&spi->dev, AD7879_DEVID, spi->irq, pdata, + dev_get_platdata(&spi->dev), &ad7879_spi_bus_ops); if (IS_ERR(ts)) return PTR_ERR(ts); diff --git a/drivers/input/touchscreen/ad7879.c b/drivers/input/touchscreen/ad7879.c index e290e7b..e763c77 100644 --- a/drivers/input/touchscreen/ad7879.c +++ b/drivers/input/touchscreen/ad7879.c @@ -486,9 +486,9 @@ static inline void ad7879_gpio_remove(struct ad7879 *ts) #endif struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq, + struct ad7879_platform_data *pdata, const struct ad7879_bus_ops *bops) { - struct ad7879_platform_data *pdata = dev_get_platdata(dev); struct ad7879 *ts; struct input_dev *input_dev; int err; diff --git a/drivers/input/touchscreen/ad7879.h b/drivers/input/touchscreen/ad7879.h index 6fd13c4..fa363a0 100644 --- a/drivers/input/touchscreen/ad7879.h +++ b/drivers/input/touchscreen/ad7879.h @@ -24,6 +24,7 @@ struct ad7879_bus_ops { extern const struct dev_pm_ops ad7879_pm_ops; struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned irq, + struct ad7879_platform_data *pdata, const struct ad7879_bus_ops *bops); void ad7879_remove(struct ad7879 *); -- 2.7.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html