[PATCHv6][ 1/4] Input: tsc2007: Add device tree support.
Rob Herring
robherring2 at gmail.com
Thu Oct 24 06:31:07 EDT 2013
On Thu, Oct 24, 2013 at 5:16 AM, Grant Likely <grant.likely at secretlab.ca> wrote:
> On Thu, 24 Oct 2013 10:38:50 +0200, Denis Carikli <denis at eukrea.com> 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 v5->v6:
>> - Fixed a code style issue.
>> - Improved the documentation to set some gpio related properties as optional.
>> - The properties related to the gpios are also explained better.
>> ---
>> .../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..46fc677
>> --- /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.
>> +- 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).
>> +- interrupt-parent: the phandle for the gpio controller
>> + (see interrupt binding[1]).
>> +- interrupts: (gpio) interrupt to which the chip is connected
>> + (see interrupt binding[1]).
>> +- pinctrl-0: Should specify pin control groups used for the gpio
>> + (see pinctrl bindings[0]).
>> +- pinctrl-names: Should contain only one value - "default"
>> + (see pinctrl bindings[0]).
>> +- max-rt: maximum pressure.
>> +- fuzzy: specifies the fuzz value that is used to filter noise from the event
>> + stream.
>
> I don't actually understand what this means, can you clarify in the
> document?
>
>> +- poll-period: how much time to wait(in millisecond) before reading again the
>> + values from the tsc2007.
>
> max-rt, fuzzy, and poll-period should probably be prefixed with "ti,".
These could be common touchscreen properties. There is also tps6507
touchscreen binding being reviewed. I haven't checked, but there's
probably already some touchscreen bindings. So this is a good
opportunity for common bindings/properties.
Rob
>
> Otherwise the binding looks good to me.
>
> g.
>
>
>> +
>> +[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..6b1d7a9 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;
>> +
>> + if (!of_property_read_u32(np, "fuzzy", &val32))
>> + ts->fuzzy = val32;
>> +
>> + if (!of_property_read_u64(np, "poll-period", &val64))
>> + ts->poll_period = val64;
>> + else
>> + ts->poll_period = 1;
>> +
>> + if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
>> + ts->x_plate_ohms = val32;
>> + } else {
>> + dev_err(&client->dev,
>> + "Error: lacking ti,x-plate-ohms devicetree property. (err %d).",
>> + err);
>> return -EINVAL;
>> }
>>
>> - if (!i2c_check_functionality(client->adapter,
>> - I2C_FUNC_SMBUS_READ_WORD_DATA))
>> - return -EIO;
>> + ts->gpio = of_get_gpio(np, 0);
>> + if (!gpio_is_valid(ts->gpio))
>> + dev_err(&client->dev,
>> + "GPIO not found (of_get_gpio returned %d)\n",
>> + ts->gpio);
>>
>> - ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
>> - input_dev = input_allocate_device();
>> - if (!ts || !input_dev) {
>> - err = -ENOMEM;
>> - goto err_free_mem;
>> - }
>> + /* Used to detect if it is probed trough the device tree,
>> + * in order to be able to use that information in the IRQ handler.
>> + */
>> + ts->of = 1;
>>
>> - ts->client = client;
>> - ts->irq = client->irq;
>> - ts->input = input_dev;
>> - init_waitqueue_head(&ts->wait);
>> + return 0;
>> +}
>> +#else
>> +static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
>> + struct device_node *np)
>> +{
>> + return -ENODEV;
>> +}
>> +#endif
>> +
>> +static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
>> + struct tsc2007_platform_data *pdata,
>> + const struct i2c_device_id *id)
>> +{
>> + if (!pdata) {
>> + dev_err(&client->dev, "platform data is required!\n");
>> + return -EINVAL;
>> + }
>>
>> ts->model = pdata->model;
>> ts->x_plate_ohms = pdata->x_plate_ohms;
>> @@ -309,13 +362,57 @@ static int tsc2007_probe(struct i2c_client *client,
>> ts->poll_period = pdata->poll_period ? : 1;
>> ts->get_pendown_state = pdata->get_pendown_state;
>> ts->clear_penirq = pdata->clear_penirq;
>> + ts->fuzzy = pdata->fuzzy;
>>
>> if (pdata->x_plate_ohms == 0) {
>> dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
>> - err = -EINVAL;
>> - goto err_free_mem;
>> + return -EINVAL;
>> }
>>
>> + /* Used to detect if it is probed trough the device tree,
>> + * in order to be able to use that information in the IRQ handler.
>> + */
>> + ts->of = 0;
>> +
>> + return 0;
>> +}
>> +
>> +static int tsc2007_probe(struct i2c_client *client,
>> + const struct i2c_device_id *id)
>> +{
>> + struct device_node *np = client->dev.of_node;
>> + struct tsc2007_platform_data *pdata = client->dev.platform_data;
>> + struct tsc2007 *ts;
>> + struct input_dev *input_dev;
>> + int err = 0;
>> +
>> + ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
>> + if (!ts)
>> + return -ENOMEM;
>> +
>> + if (np)
>> + err = tsc2007_probe_dt(client, ts, np);
>> + else
>> + err = tsc2007_probe_pdev(client, ts, pdata, id);
>> +
>> + if (err)
>> + return err;
>> +
>> + if (!i2c_check_functionality(client->adapter,
>> + I2C_FUNC_SMBUS_READ_WORD_DATA))
>> + return -EIO;
>> +
>> + input_dev = input_allocate_device();
>> + if (!input_dev) {
>> + err = -ENOMEM;
>> + goto err_free_input;
>> + };
>> +
>> + ts->client = client;
>> + ts->irq = client->irq;
>> + ts->input = input_dev;
>> + init_waitqueue_head(&ts->wait);
>> +
>> snprintf(ts->phys, sizeof(ts->phys),
>> "%s/input0", dev_name(&client->dev));
>>
>> @@ -331,19 +428,21 @@ static int tsc2007_probe(struct i2c_client *client,
>> input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
>> input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
>>
>> - input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, pdata->fuzzx, 0);
>> - input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, pdata->fuzzy, 0);
>> + input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzy, 0);
>> + input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
>> input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
>> - pdata->fuzzz, 0);
>> + ts->fuzzy, 0);
>>
>> - if (pdata->init_platform_hw)
>> - pdata->init_platform_hw();
>> + if (!np) {
>> + if (pdata->init_platform_hw)
>> + pdata->init_platform_hw();
>> + }
>>
>> err = request_threaded_irq(ts->irq, tsc2007_hard_irq, tsc2007_soft_irq,
>> IRQF_ONESHOT, client->dev.driver->name, ts);
>> if (err < 0) {
>> dev_err(&client->dev, "irq %d busy?\n", ts->irq);
>> - goto err_free_mem;
>> + goto err_free_input;
>> }
>>
>> tsc2007_stop(ts);
>> @@ -358,23 +457,27 @@ static int tsc2007_probe(struct i2c_client *client,
>>
>> err_free_irq:
>> free_irq(ts->irq, ts);
>> - if (pdata->exit_platform_hw)
>> - pdata->exit_platform_hw();
>> - err_free_mem:
>> + if (!np) {
>> + if (pdata->exit_platform_hw)
>> + pdata->exit_platform_hw();
>> + }
>> + err_free_input:
>> input_free_device(input_dev);
>> - kfree(ts);
>> return err;
>> }
>>
>> static int tsc2007_remove(struct i2c_client *client)
>> {
>> + struct device_node *np = client->dev.of_node;
>> struct tsc2007 *ts = i2c_get_clientdata(client);
>> struct tsc2007_platform_data *pdata = client->dev.platform_data;
>>
>> free_irq(ts->irq, ts);
>>
>> - if (pdata->exit_platform_hw)
>> - pdata->exit_platform_hw();
>> + if (!np) {
>> + if (pdata->exit_platform_hw)
>> + pdata->exit_platform_hw();
>> + }
>>
>> input_unregister_device(ts->input);
>> kfree(ts);
>> @@ -389,10 +492,19 @@ static const struct i2c_device_id tsc2007_idtable[] = {
>>
>> MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
>>
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id tsc2007_of_match[] = {
>> + { .compatible = "ti,tsc2007" },
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, tsc2007_of_match);
>> +#endif
>> +
>> static struct i2c_driver tsc2007_driver = {
>> .driver = {
>> .owner = THIS_MODULE,
>> - .name = "tsc2007"
>> + .name = "tsc2007",
>> + .of_match_table = of_match_ptr(tsc2007_of_match),
>> },
>> .id_table = tsc2007_idtable,
>> .probe = tsc2007_probe,
>> --
>> 1.7.9.5
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
>
>
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