Input: eeti_ts: pass gpio value instead of IRQ

commit 4eef6cbfcc03b294d9d334368a851b35b496ce53 upstream.

The EETI touchscreen asserts its IRQ line as soon as it has data in its
internal buffers. The line is automatically deasserted once all data has
been read via I2C. Hence, the driver has to monitor the GPIO line and
cannot simply rely on the interrupt handler reception.

In the current implementation of the driver, irq_to_gpio() is used to
determine the GPIO number from the i2c_client's IRQ value.

As irq_to_gpio() is not available on all platforms, this patch changes
this and makes the driver ignore the passed in IRQ. Instead, a GPIO is
added to the platform_data struct and gpio_to_irq is used to derive the
IRQ from that GPIO. If this fails, bail out. The driver is only able to
work in environments where the touchscreen GPIO can be mapped to an
IRQ.

Without this patch, building raumfeld_defconfig results in:

drivers/input/touchscreen/eeti_ts.c: In function 'eeti_ts_irq_active':
drivers/input/touchscreen/eeti_ts.c:65:2: error: implicit declaration of function 'irq_to_gpio' [-Werror=implicit-function-declaration]

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Sven Neumann <s.neumann@raumfeld.com>
Cc: linux-input@vger.kernel.org
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
[bwh: Backported to 3.2: raumfeld_controller_i2c_board_info.irq was
 initialised using gpio_to_irq(), but this doesn't seem to matter]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/arm/mach-pxa/raumfeld.c b/arch/arm/mach-pxa/raumfeld.c
index f0c05f4d12ed5eb48715d8433665b20199bde3bd..ae7786dfe0c4cee78c65972e4dbfd5d63bcd7a7b 100644 (file)
--- a/arch/arm/mach-pxa/raumfeld.c
+++ b/arch/arm/mach-pxa/raumfeld.c
@@ -951,12 +951,12 @@ static struct i2c_board_info raumfeld_connector_i2c_board_info __initdata = {
 
 static struct eeti_ts_platform_data eeti_ts_pdata = {
        .irq_active_high = 1,
+       .irq_gpio = GPIO_TOUCH_IRQ,
 };
 
 static struct i2c_board_info raumfeld_controller_i2c_board_info __initdata = {
        .type   = "eeti_ts",
        .addr   = 0x0a,
-       .irq    = gpio_to_irq(GPIO_TOUCH_IRQ),
        .platform_data = &eeti_ts_pdata,
 };
 

diff --git a/drivers/input/touchscreen/eeti_ts.c b/drivers/input/touchscreen/eeti_ts.c
index 7f8f538a9806d067f7aef37943d8050d041f50ac..4f938bb05ae20356d49709e052fee73db3e92614 100644 (file)
--- a/drivers/input/touchscreen/eeti_ts.c
+++ b/drivers/input/touchscreen/eeti_ts.c
@@ -48,7 +48,7 @@ struct eeti_ts_priv {
        struct input_dev *input;
        struct work_struct work;
        struct mutex mutex;
-       int irq, irq_active_high;
+       int irq_gpio, irq, irq_active_high;
 };
 
 #define EETI_TS_BITDEPTH       (11)
@@ -62,7 +62,7 @@ struct eeti_ts_priv {
 
 static inline int eeti_ts_irq_active(struct eeti_ts_priv *priv)
 {
-       return gpio_get_value(irq_to_gpio(priv->irq)) == priv->irq_active_high;
+       return gpio_get_value(priv->irq_gpio) == priv->irq_active_high;
 }
 
 static void eeti_ts_read(struct work_struct *work)
@@ -157,7 +157,7 @@ static void eeti_ts_close(struct input_dev *dev)
 static int __devinit eeti_ts_probe(struct i2c_client *client,
                                   const struct i2c_device_id *idp)
 {
-       struct eeti_ts_platform_data *pdata;
+       struct eeti_ts_platform_data *pdata = client->dev.platform_data;
        struct eeti_ts_priv *priv;
        struct input_dev *input;
        unsigned int irq_flags;
@@ -199,9 +199,12 @@ static int __devinit eeti_ts_probe(struct i2c_client *client,
 
        priv->client = client;
        priv->input = input;
-       priv->irq = client->irq;
+       priv->irq_gpio = pdata->irq_gpio;
+       priv->irq = gpio_to_irq(pdata->irq_gpio);
 
-       pdata = client->dev.platform_data;
+       err = gpio_request_one(pdata->irq_gpio, GPIOF_IN, client->name);
+       if (err < 0)
+               goto err1;
 
        if (pdata)
                priv->irq_active_high = pdata->irq_active_high;
@@ -215,13 +218,13 @@ static int __devinit eeti_ts_probe(struct i2c_client *client,
 
        err = input_register_device(input);
        if (err)
-               goto err1;
+               goto err2;
 
        err = request_irq(priv->irq, eeti_ts_isr, irq_flags,
                          client->name, priv);
        if (err) {
                dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
-               goto err2;
+               goto err3;
        }
 
        /*
@@ -233,9 +236,11 @@ static int __devinit eeti_ts_probe(struct i2c_client *client,
        device_init_wakeup(&client->dev, 0);
        return 0;
 
-err2:
+err3:
        input_unregister_device(input);
        input = NULL; /* so we dont try to free it below */
+err2:
+       gpio_free(pdata->irq_gpio);
 err1:
        input_free_device(input);
        kfree(priv);

diff --git a/include/linux/input/eeti_ts.h b/include/linux/input/eeti_ts.h
index f875b316249d257ce2f56e7243e4463c9d4994e2..16625d799b6fc1ca85f89d5d9f81415332c8e86e 100644 (file)
--- a/include/linux/input/eeti_ts.h
+++ b/include/linux/input/eeti_ts.h
@@ -2,6 +2,7 @@
 #define LINUX_INPUT_EETI_TS_H
 
 struct eeti_ts_platform_data {
+       int irq_gpio;
        unsigned int irq_active_high;
 };