Skip to content

Commit

Permalink
V4L/DVB (13176): adv7180: Support checking standard via interrupts
Browse files Browse the repository at this point in the history 
If the I2C device provides an interrupt it is registered and the
standard
is updated via interrupts rather than polling.

Since I2C communication is needed, the interrupt handler fires off a
work which will check the new standard, and store it in the internal
structure.

To handle mutual exclusion a mutex is introduced.

Signed-off-by: Richard Röjfors <richard.rojfors@mocean-labs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
  • Loading branch information
Richard Röjfors authored and Mauro Carvalho Chehab committed Dec 5, 2009
1 parent 527aebf commit 42752f7
Showing 1 changed file with 168 additions and 17 deletions.
185 changes: 168 additions & 17 deletions drivers/media/video/adv7180.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,7 @@
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <linux/mutex.h>

#define DRIVER_NAME "adv7180"

Expand All @@ -48,9 +49,14 @@
#define ADV7180_INPUT_CONTROL_PAL_SECAM 0xe0
#define ADV7180_INPUT_CONTROL_PAL_SECAM_PED 0xf0

#define ADV7180_AUTODETECT_ENABLE_REG 0x07
#define ADV7180_AUTODETECT_DEFAULT 0x7f
#define ADV7180_EXTENDED_OUTPUT_CONTROL_REG 0x04
#define ADV7180_EXTENDED_OUTPUT_CONTROL_NTSCDIS 0xC5

#define ADV7180_AUTODETECT_ENABLE_REG 0x07
#define ADV7180_AUTODETECT_DEFAULT 0x7f

#define ADV7180_ADI_CTRL_REG 0x0e
#define ADV7180_ADI_CTRL_IRQ_SPACE 0x20

#define ADV7180_STATUS1_REG 0x10
#define ADV7180_STATUS1_IN_LOCK 0x01
Expand All @@ -67,9 +73,28 @@
#define ADV7180_IDENT_REG 0x11
#define ADV7180_ID_7180 0x18

#define ADV7180_ICONF1_ADI 0x40
#define ADV7180_ICONF1_ACTIVE_LOW 0x01
#define ADV7180_ICONF1_PSYNC_ONLY 0x10
#define ADV7180_ICONF1_ACTIVE_TO_CLR 0xC0

#define ADV7180_IRQ1_LOCK 0x01
#define ADV7180_IRQ1_UNLOCK 0x02
#define ADV7180_ISR1_ADI 0x42
#define ADV7180_ICR1_ADI 0x43
#define ADV7180_IMR1_ADI 0x44
#define ADV7180_IMR2_ADI 0x48
#define ADV7180_IRQ3_AD_CHANGE 0x08
#define ADV7180_ISR3_ADI 0x4A
#define ADV7180_ICR3_ADI 0x4B
#define ADV7180_IMR3_ADI 0x4C
#define ADV7180_IMR4_ADI 0x50

struct adv7180_state {
struct v4l2_subdev sd;
struct work_struct work;
struct mutex mutex; /* mutual excl. when accessing chip */
int irq;
v4l2_std_id curr_norm;
bool autodetect;
};
Expand Down Expand Up @@ -153,19 +178,30 @@ static inline struct adv7180_state *to_state(struct v4l2_subdev *sd)
static int adv7180_querystd(struct v4l2_subdev *sd, v4l2_std_id *std)
{
struct adv7180_state *state = to_state(sd);
int err = 0;
int err = mutex_lock_interruptible(&state->mutex);
if (err)
return err;

if (!state->autodetect)
/* when we are interrupt driven we know the state */
if (!state->autodetect || state->irq > 0)
*std = state->curr_norm;
else
err = __adv7180_status(v4l2_get_subdevdata(sd), NULL, std);

mutex_unlock(&state->mutex);
return err;
}

static int adv7180_g_input_status(struct v4l2_subdev *sd, u32 *status)
{
return __adv7180_status(v4l2_get_subdevdata(sd), status, NULL);
struct adv7180_state *state = to_state(sd);
int ret = mutex_lock_interruptible(&state->mutex);
if (ret)
return ret;

ret = __adv7180_status(v4l2_get_subdevdata(sd), status, NULL);
mutex_unlock(&state->mutex);
return ret;
}

static int adv7180_g_chip_ident(struct v4l2_subdev *sd,
Expand All @@ -180,7 +216,9 @@ static int adv7180_s_std(struct v4l2_subdev *sd, v4l2_std_id std)
{
struct adv7180_state *state = to_state(sd);
struct i2c_client *client = v4l2_get_subdevdata(sd);
int ret;
int ret = mutex_lock_interruptible(&state->mutex);
if (ret)
return ret;

/* all standards -> autodetect */
if (std == V4L2_STD_ALL) {
Expand All @@ -190,6 +228,7 @@ static int adv7180_s_std(struct v4l2_subdev *sd, v4l2_std_id std)
if (ret < 0)
goto out;

__adv7180_status(client, NULL, &state->curr_norm);
state->autodetect = true;
} else {
ret = v4l2_std_to_adv7180(std);
Expand All @@ -206,6 +245,7 @@ static int adv7180_s_std(struct v4l2_subdev *sd, v4l2_std_id std)
}
ret = 0;
out:
mutex_unlock(&state->mutex);
return ret;
}

Expand All @@ -224,6 +264,39 @@ static const struct v4l2_subdev_ops adv7180_ops = {
.video = &adv7180_video_ops,
};

static void adv7180_work(struct work_struct *work)
{
struct adv7180_state *state = container_of(work, struct adv7180_state,
work);
struct i2c_client *client = v4l2_get_subdevdata(&state->sd);
u8 isr3;

mutex_lock(&state->mutex);
i2c_smbus_write_byte_data(client, ADV7180_ADI_CTRL_REG,
ADV7180_ADI_CTRL_IRQ_SPACE);
isr3 = i2c_smbus_read_byte_data(client, ADV7180_ISR3_ADI);
/* clear */
i2c_smbus_write_byte_data(client, ADV7180_ICR3_ADI, isr3);
i2c_smbus_write_byte_data(client, ADV7180_ADI_CTRL_REG, 0);

if (isr3 & ADV7180_IRQ3_AD_CHANGE && state->autodetect)
__adv7180_status(client, NULL, &state->curr_norm);
mutex_unlock(&state->mutex);

enable_irq(state->irq);
}

static irqreturn_t adv7180_irq(int irq, void *devid)
{
struct adv7180_state *state = devid;

schedule_work(&state->work);

disable_irq_nosync(state->irq);

return IRQ_HANDLED;
}

/*
* Generic i2c probe
* concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
Expand All @@ -244,33 +317,111 @@ static __devinit int adv7180_probe(struct i2c_client *client,
client->addr << 1, client->adapter->name);

state = kzalloc(sizeof(struct adv7180_state), GFP_KERNEL);
if (state == NULL)
return -ENOMEM;
if (state == NULL) {
ret = -ENOMEM;
goto err;
}

state->irq = client->irq;
INIT_WORK(&state->work, adv7180_work);
mutex_init(&state->mutex);
state->autodetect = true;
sd = &state->sd;
v4l2_i2c_subdev_init(sd, client, &adv7180_ops);

/* Initialize adv7180 */
/* enable autodetection */
/* Enable autodetection */
ret = i2c_smbus_write_byte_data(client, ADV7180_INPUT_CONTROL_REG,
ADV7180_INPUT_CONTROL_AD_PAL_BG_NTSC_J_SECAM);
if (ret > 0)
ret = i2c_smbus_write_byte_data(client,
ADV7180_AUTODETECT_ENABLE_REG,
ADV7180_AUTODETECT_DEFAULT);
if (ret < 0) {
printk(KERN_ERR DRIVER_NAME
": Failed to communicate to chip: %d\n", ret);
return ret;
if (ret < 0)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_AUTODETECT_ENABLE_REG,
ADV7180_AUTODETECT_DEFAULT);
if (ret < 0)
goto err_unreg_subdev;

/* ITU-R BT.656-4 compatible */
ret = i2c_smbus_write_byte_data(client,
ADV7180_EXTENDED_OUTPUT_CONTROL_REG,
ADV7180_EXTENDED_OUTPUT_CONTROL_NTSCDIS);
if (ret < 0)
goto err_unreg_subdev;

/* read current norm */
__adv7180_status(client, NULL, &state->curr_norm);

/* register for interrupts */
if (state->irq > 0) {
ret = request_irq(state->irq, adv7180_irq, 0, DRIVER_NAME,
state);
if (ret)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_ADI_CTRL_REG,
ADV7180_ADI_CTRL_IRQ_SPACE);
if (ret < 0)
goto err_unreg_subdev;

/* config the Interrupt pin to be active low */
ret = i2c_smbus_write_byte_data(client, ADV7180_ICONF1_ADI,
ADV7180_ICONF1_ACTIVE_LOW | ADV7180_ICONF1_PSYNC_ONLY);
if (ret < 0)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_IMR1_ADI, 0);
if (ret < 0)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_IMR2_ADI, 0);
if (ret < 0)
goto err_unreg_subdev;

/* enable AD change interrupts interrupts */
ret = i2c_smbus_write_byte_data(client, ADV7180_IMR3_ADI,
ADV7180_IRQ3_AD_CHANGE);
if (ret < 0)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_IMR4_ADI, 0);
if (ret < 0)
goto err_unreg_subdev;

ret = i2c_smbus_write_byte_data(client, ADV7180_ADI_CTRL_REG,
0);
if (ret < 0)
goto err_unreg_subdev;
}

return 0;

err_unreg_subdev:
mutex_destroy(&state->mutex);
v4l2_device_unregister_subdev(sd);
kfree(state);
err:
printk(KERN_ERR DRIVER_NAME ": Failed to probe: %d\n", ret);
return ret;
}

static __devexit int adv7180_remove(struct i2c_client *client)
{
struct v4l2_subdev *sd = i2c_get_clientdata(client);
struct adv7180_state *state = to_state(sd);

if (state->irq > 0) {
free_irq(client->irq, state);
if (cancel_work_sync(&state->work)) {
/*
* Work was pending, therefore we need to enable
* IRQ here to balance the disable_irq() done in the
* interrupt handler.
*/
enable_irq(state->irq);
}
}

mutex_destroy(&state->mutex);
v4l2_device_unregister_subdev(sd);
kfree(to_state(sd));
return 0;
Expand Down

0 comments on commit 42752f7

Please sign in to comment.