[PATCHv5][ 1/4] Input: tsc2007: Add device tree support.
Rob Herring
robherring2 at gmail.com
Wed Oct 23 18:18:27 EDT 2013
On 10/23/2013 07:10 AM, Denis Carikli wrote:
> Cc: Rob Herring <rob.herring at calxeda.com>
> Cc: Pawel Moll <pawel.moll at arm.com>
> Cc: Mark Rutland <mark.rutland at arm.com>
> Cc: Stephen Warren <swarren at wwwdotorg.org>
> Cc: Ian Campbell <ijc+devicetree at hellion.org.uk>
> Cc: devicetree at vger.kernel.org
> Cc: Dmitry Torokhov <dmitry.torokhov at gmail.com>
> Cc: linux-input at vger.kernel.org
> Cc: Sascha Hauer <kernel at pengutronix.de>
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: Lothar Waßmann <LW at KARO-electronics.de>
> Cc: Eric Bénard <eric at eukrea.com>
> Signed-off-by: Denis Carikli <denis at eukrea.com>
> ---
> ChangeLog v4->v5:
> - Most of the "if (ts->of)" were replaced by wrapping them in the
> tsc2007_is_pen_down_valid and tsc2007_is_pen_down functions.
> - Some whitespace cleanups.
> - The devm_kzalloc call was fixed to make it compile.
> ---
> .../bindings/input/touchscreen/tsc2007.txt | 44 +++++
> drivers/input/touchscreen/tsc2007.c | 194 +++++++++++++++-----
> 2 files changed, 197 insertions(+), 41 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
>
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
> new file mode 100644
> index 0000000..fadd3f6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
> @@ -0,0 +1,44 @@
> +* Texas Instruments tsc2007 touchscreen controller
> +
> +Required properties:
> +- compatible: must be "ti,tsc2007".
> +- reg: I2C address of the chip.
> +- pinctrl-0: Should specify pin control groups used for this controller
> + (see pinctrl bindings[0]).
> +- pinctrl-names: Should contain only one value - "default"
> + (see pinctrl bindings[0]).
I'm confused why an i2c slave needs pinctl binding?
> +- interrupt-parent: the phandle for the interrupt controller
> + (see interrupt binding[1]).
> +- interrupts: interrupt to which the chip is connected
> + (see interrupt binding[1]).
> +- ti,x-plate-ohms: X-plate resistance in ohms.
> +
> +Optional properties:
> +- gpios: the interrupt gpio the chip is connected to (trough the penirq pin)
> + (see GPIO binding[2] for more details).
> +- max-rt: maximum pressure.
> +- fuzzy: specifies the fuzz value that is used to filter noise from the event
> + stream.
> +- poll-period: how much time to wait(in millisecond) before reading again the
> + values from the tsc2007.
> +
> +[0]: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
> +[1]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
> +[2]: Documentation/devicetree/bindings/gpio/gpio.txt
> +
> +Example:
> + &i2c1 {
> + /* ... */
> + tsc2007 at 49 {
> + compatible = "ti,tsc2007";
> + reg = <0x49>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_tsc2007_1>;
> + interrupt-parent = <&gpio4>;
> + interrupts = <0x0 0x8>;
> + gpios = <&gpio4 0 0>;
> + ti,x-plate-ohms = <180>;
> + };
> +
> + /* ... */
> + };
> diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
> index 0b67ba4..0625fe1 100644
> --- a/drivers/input/touchscreen/tsc2007.c
> +++ b/drivers/input/touchscreen/tsc2007.c
> @@ -26,6 +26,9 @@
> #include <linux/interrupt.h>
> #include <linux/i2c.h>
> #include <linux/i2c/tsc2007.h>
> +#include <linux/of_device.h>
> +#include <linux/of.h>
> +#include <linux/of_gpio.h>
>
> #define TSC2007_MEASURE_TEMP0 (0x0 << 4)
> #define TSC2007_MEASURE_AUX (0x2 << 4)
> @@ -74,7 +77,10 @@ struct tsc2007 {
> u16 max_rt;
> unsigned long poll_delay;
> unsigned long poll_period;
> + int fuzzy;
> + char of;
>
> + unsigned gpio;
> int irq;
>
> wait_queue_head_t wait;
> @@ -84,6 +90,11 @@ struct tsc2007 {
> void (*clear_penirq)(void);
> };
>
> +static int tsc2007_get_pendown_state_dt(struct tsc2007 *ts)
> +{
> + return !gpio_get_value(ts->gpio);
> +}
> +
> static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
> {
> s32 data;
> @@ -142,6 +153,14 @@ static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
> return rt;
> }
>
> +static bool tsc2007_is_pen_down_valid(struct tsc2007 *ts)
> +{
> + if (ts->of)
> + return gpio_is_valid(ts->gpio);
> + else
> + return ts->get_pendown_state ? true : false;
> +}
> +
> static bool tsc2007_is_pen_down(struct tsc2007 *ts)
> {
> /*
> @@ -158,10 +177,13 @@ static bool tsc2007_is_pen_down(struct tsc2007 *ts)
> * to fall back on the pressure reading.
> */
>
> - if (!ts->get_pendown_state)
> + if (!tsc2007_is_pen_down_valid(ts))
> return true;
>
> - return ts->get_pendown_state();
> + if (ts->of)
> + return tsc2007_get_pendown_state_dt(ts);
> + else
> + return ts->get_pendown_state();
> }
>
> static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
> @@ -178,7 +200,7 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
>
> rt = tsc2007_calculate_pressure(ts, &tc);
>
> - if (rt == 0 && !ts->get_pendown_state) {
> + if(!rt && !tsc2007_is_pen_down_valid(ts)) {
> /*
> * If pressure reported is 0 and we don't have
> * callback to check pendown state, we have to
> @@ -228,7 +250,7 @@ static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
> {
> struct tsc2007 *ts = handle;
>
> - if (!ts->get_pendown_state || likely(ts->get_pendown_state()))
> + if (tsc2007_is_pen_down(ts))
> return IRQ_WAKE_THREAD;
>
> if (ts->clear_penirq)
> @@ -273,34 +295,65 @@ static void tsc2007_close(struct input_dev *input_dev)
> tsc2007_stop(ts);
> }
>
> -static int tsc2007_probe(struct i2c_client *client,
> - const struct i2c_device_id *id)
> +#ifdef CONFIG_OF
> +static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
> + struct device_node *np)
> {
> - struct tsc2007 *ts;
> - struct tsc2007_platform_data *pdata = client->dev.platform_data;
> - struct input_dev *input_dev;
> - int err;
> -
> - if (!pdata) {
> - dev_err(&client->dev, "platform data is required!\n");
> + int err = 0;
> + u32 val32;
> + u64 val64;
> +
> + if (!of_property_read_u32(np, "max-rt", &val32))
> + ts->max_rt = val32;
> + else
> + ts->max_rt = MAX_12BIT;
These functions don't overwrite the value if the property isn't present.
So you can set the values to the defaults and just pass the variable
(i.e. ts->max_rt) to of_property_read_u32 directly.
Rob
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