On 2016-01-26 00:14, Michael Hennerich wrote: > On 01/26/2016 04:04 AM, Stefan Agner wrote: >> 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> > > > Hi Stefan, > > Thanks for the patch - > There is something similar in our tree but I forgot to send it > mainline a long time ago. > > https://github.com/analogdevicesinc/linux/commit/69b16d4b616a4bbe9001d3f67d3ff54f3deb85ce Yeah I saw that patch. I tried to use the standard touchscreen properties where applicable. Also, my implementation is currently only for I2C. However, when I now think about it, I might as well move my code into ad7879.c which would enable to use the same bindings for SPI devices too. > > There are some build issues can you have a look? Yeah I saw, shame on me. Will fix them. > > I also don't understand why "exporting the GPIO is not possible > through device tree"? > > Can you explain? I should have written "not implemented" instead of "not possible". To implement proper device tree GPIO bindings it would need some more changes. I did not look into that, hence the current device tree bindings do not allow to enable the GPIO functionality. -- Stefan > > Regards, > Michael > > >> --- >> .../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 *); >> >> -- 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
