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Input: tsc2007 - properly shut off interrupts/delayed work
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Properly shut off interrupts/delayed work by free-ing IRQ first
and then ensuring that enable/disable is balanced. Also add
__devinit/__devexit markings, restore poll delay/period scheduling
logic, make sure we call exit_platform_hw() method when probe
fails.

Tested-by: Richard Röjfors <richard.rojfors.ext@mocean-labs.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Dmitry Torokhov committed Jul 26, 2009
1 parent 75fba3b commit 141586b
Showing 1 changed file with 42 additions and 30 deletions.
72 changes: 42 additions & 30 deletions drivers/input/touchscreen/tsc2007.c
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Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,8 @@
#include <linux/i2c.h>
#include <linux/i2c/tsc2007.h>

#define TS_POLL_PERIOD msecs_to_jiffies(1) /* ms delay between samples */
#define TS_POLL_DELAY 1 /* ms delay between samples */
#define TS_POLL_PERIOD 1 /* ms delay between samples */

#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
#define TSC2007_MEASURE_AUX (0x2 << 4)
Expand Down Expand Up @@ -76,7 +77,7 @@ struct tsc2007 {
u16 model;
u16 x_plate_ohms;

unsigned pendown;
bool pendown;
int irq;

int (*get_pendown_state)(void);
Expand Down Expand Up @@ -131,18 +132,18 @@ static void tsc2007_send_event(void *tsc)
} else
rt = 0;

/* Sample found inconsistent by debouncing or pressure is beyond
/*
* Sample found inconsistent by debouncing or pressure is beyond
* the maximum. Don't report it to user space, repeat at least
* once more the measurement
*/
if (rt > MAX_12BIT) {
dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);

schedule_delayed_work(&ts->work, TS_POLL_PERIOD);
return;
}

/* NOTE: We can't rely on the pressure to determine the pen down
/*
* NOTE: We can't rely on the pressure to determine the pen down
* state, even this controller has a pressure sensor. The pressure
* value can fluctuate for quite a while after lifting the pen and
* in some cases may not even settle at the expected value.
Expand All @@ -157,7 +158,7 @@ static void tsc2007_send_event(void *tsc)
dev_dbg(&ts->client->dev, "DOWN\n");

input_report_key(input, BTN_TOUCH, 1);
ts->pendown = 1;
ts->pendown = true;
}

input_report_abs(input, ABS_X, x);
Expand All @@ -169,8 +170,6 @@ static void tsc2007_send_event(void *tsc)
dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
x, y, rt);
}

schedule_delayed_work(&ts->work, TS_POLL_PERIOD);
}

static int tsc2007_read_values(struct tsc2007 *tsc)
Expand All @@ -195,6 +194,7 @@ static void tsc2007_work(struct work_struct *work)
{
struct tsc2007 *ts =
container_of(to_delayed_work(work), struct tsc2007, work);

if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
struct input_dev *input = ts->input;

Expand All @@ -204,14 +204,17 @@ static void tsc2007_work(struct work_struct *work)
input_report_abs(input, ABS_PRESSURE, 0);
input_sync(input);

ts->pendown = 0;
ts->pendown = false;
enable_irq(ts->irq);
} else {
/* pen is still down, continue with the measurement */
dev_dbg(&ts->client->dev, "pen is still down\n");

tsc2007_read_values(ts);
tsc2007_send_event(ts);

schedule_delayed_work(&ts->work,
msecs_to_jiffies(TS_POLL_PERIOD));
}
}

Expand All @@ -221,7 +224,8 @@ static irqreturn_t tsc2007_irq(int irq, void *handle)

if (likely(ts->get_pendown_state())) {
disable_irq_nosync(ts->irq);
schedule_delayed_work(&ts->work, 0);
schedule_delayed_work(&ts->work,
msecs_to_jiffies(TS_POLL_DELAY));
}

if (ts->clear_penirq)
Expand All @@ -230,8 +234,21 @@ static irqreturn_t tsc2007_irq(int irq, void *handle)
return IRQ_HANDLED;
}

static int tsc2007_probe(struct i2c_client *client,
const struct i2c_device_id *id)
static void tsc2007_free_irq(struct tsc2007 *ts)
{
free_irq(ts->irq, ts);
if (cancel_delayed_work_sync(&ts->work)) {
/*
* Work was pending, therefore we need to enable
* IRQ here to balance the disable_irq() done in the
* interrupt handler.
*/
enable_irq(ts->irq);
}
}

static int __devinit tsc2007_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct tsc2007 *ts;
struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
Expand All @@ -255,17 +272,15 @@ static int tsc2007_probe(struct i2c_client *client,
}

ts->client = client;
i2c_set_clientdata(client, ts);

ts->irq = client->irq;
ts->input = input_dev;
INIT_DELAYED_WORK(&ts->work, tsc2007_work);

ts->model = pdata->model;
ts->x_plate_ohms = pdata->x_plate_ohms;
ts->get_pendown_state = pdata->get_pendown_state;
ts->clear_penirq = pdata->clear_penirq;

pdata->init_platform_hw();

snprintf(ts->phys, sizeof(ts->phys),
"%s/input0", dev_name(&client->dev));

Expand All @@ -280,11 +295,7 @@ static int tsc2007_probe(struct i2c_client *client,
input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);

tsc2007_read_values(ts);

ts->irq = client->irq;

INIT_DELAYED_WORK(&ts->work, tsc2007_work);
pdata->init_platform_hw();

err = request_irq(ts->irq, tsc2007_irq, 0,
client->dev.driver->name, ts);
Expand All @@ -297,29 +308,30 @@ static int tsc2007_probe(struct i2c_client *client,
if (err)
goto err_free_irq;

dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
i2c_set_clientdata(client, ts);

tsc2007_read_values(ts);

return 0;

err_free_irq:
free_irq(ts->irq, ts);
tsc2007_free_irq(ts);
pdata->exit_platform_hw();
err_free_mem:
input_free_device(input_dev);
kfree(ts);
return err;
}

static int tsc2007_remove(struct i2c_client *client)
static int __devexit tsc2007_remove(struct i2c_client *client)
{
struct tsc2007 *ts = i2c_get_clientdata(client);
struct tsc2007_platform_data *pdata;
struct tsc2007_platform_data *pdata = client->dev.platform_data;

cancel_delayed_work_sync(&ts->work);
tsc2007_free_irq(ts);

pdata = client->dev.platform_data;
pdata->exit_platform_hw();

free_irq(ts->irq, ts);
input_unregister_device(ts->input);
kfree(ts);

Expand All @@ -340,7 +352,7 @@ static struct i2c_driver tsc2007_driver = {
},
.id_table = tsc2007_idtable,
.probe = tsc2007_probe,
.remove = tsc2007_remove,
.remove = __devexit_p(tsc2007_remove),
};

static int __init tsc2007_init(void)
Expand Down

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