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[media] si4713: Modified i2c driver to handle cases where interrupts are not used

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Checks have been introduced at several places in the code to test if an
interrupt is set or not. For devices which do not use the interrupt, to
get a valid response, within a specified timeout, the device is polled
instead.

Signed-off-by: Dinesh Ram <dinesh.ram@cern.ch>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Eduardo Valentin <edubezval@gmail.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Dinesh Ram 2013-10-15 12:24:38 -03:00 committed by Mauro Carvalho Chehab
parent 7391232e12
commit 5173332c1e
1 changed files with 62 additions and 42 deletions
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104
drivers/media/radio/si4713/si4713.c
View file

@ -27,11 +27,11 @@
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/module.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-common.h>
#include <linux/regulator/consumer.h>
#include "si4713.h"
@ -213,6 +213,7 @@ static int si4713_send_command(struct si4713_device *sdev, const u8 command,
u8 response[], const int respn, const int usecs)
{
struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
unsigned long until_jiffies;
u8 data1[MAX_ARGS + 1];
int err;
@ -228,30 +229,39 @@ static int si4713_send_command(struct si4713_device *sdev, const u8 command,
if (err != argn + 1) {
v4l2_err(&sdev->sd, "Error while sending command 0x%02x\n",
command);
return (err > 0) ? -EIO : err;
return err < 0 ? err : -EIO;
}
until_jiffies = jiffies + usecs_to_jiffies(usecs) + 1;
/* Wait response from interrupt */
if (!wait_for_completion_timeout(&sdev->work,
if (client->irq) {
if (!wait_for_completion_timeout(&sdev->work,
usecs_to_jiffies(usecs) + 1))
v4l2_warn(&sdev->sd,
v4l2_warn(&sdev->sd,
"(%s) Device took too much time to answer.\n",
__func__);
/* Then get the response */
err = i2c_master_recv(client, response, respn);
if (err != respn) {
v4l2_err(&sdev->sd,
"Error while reading response for command 0x%02x\n",
command);
return (err > 0) ? -EIO : err;
}
DBG_BUFFER(&sdev->sd, "Response", response, respn);
if (check_command_failed(response[0]))
return -EBUSY;
do {
err = i2c_master_recv(client, response, respn);
if (err != respn) {
v4l2_err(&sdev->sd,
"Error %d while reading response for command 0x%02x\n",
err, command);
return err < 0 ? err : -EIO;
}
return 0;
DBG_BUFFER(&sdev->sd, "Response", response, respn);
if (!check_command_failed(response[0]))
return 0;
if (client->irq)
return -EBUSY;
msleep(1);
} while (jiffies <= until_jiffies);
return -EBUSY;
}
/*
@ -344,14 +354,15 @@ static int si4713_write_property(struct si4713_device *sdev, u16 prop, u16 val)
*/
static int si4713_powerup(struct si4713_device *sdev)
{
struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
int err;
u8 resp[SI4713_PWUP_NRESP];
/*
* .First byte = Enabled interrupts and boot function
* .Second byte = Input operation mode
*/
const u8 args[SI4713_PWUP_NARGS] = {
SI4713_PWUP_CTSIEN | SI4713_PWUP_GPO2OEN | SI4713_PWUP_FUNC_TX,
u8 args[SI4713_PWUP_NARGS] = {
SI4713_PWUP_GPO2OEN | SI4713_PWUP_FUNC_TX,
SI4713_PWUP_OPMOD_ANALOG,
};
@ -369,6 +380,9 @@ static int si4713_powerup(struct si4713_device *sdev)
gpio_set_value(sdev->gpio_reset, 1);
}
if (client->irq)
args[0] |= SI4713_PWUP_CTSIEN;
err = si4713_send_command(sdev, SI4713_CMD_POWER_UP,
args, ARRAY_SIZE(args),
resp, ARRAY_SIZE(resp),
@ -380,7 +394,8 @@ static int si4713_powerup(struct si4713_device *sdev)
v4l2_dbg(1, debug, &sdev->sd, "Device in power up mode\n");
sdev->power_state = POWER_ON;
err = si4713_write_property(sdev, SI4713_GPO_IEN,
if (client->irq)
err = si4713_write_property(sdev, SI4713_GPO_IEN,
SI4713_STC_INT | SI4713_CTS);
} else {
if (gpio_is_valid(sdev->gpio_reset))
@ -465,33 +480,39 @@ static int si4713_checkrev(struct si4713_device *sdev)
*/
static int si4713_wait_stc(struct si4713_device *sdev, const int usecs)
{
int err;
struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
u8 resp[SI4713_GET_STATUS_NRESP];
unsigned long start_jiffies = jiffies;
int err;
/* Wait response from STC interrupt */
if (!wait_for_completion_timeout(&sdev->work,
usecs_to_jiffies(usecs) + 1))
if (client->irq &&
!wait_for_completion_timeout(&sdev->work, usecs_to_jiffies(usecs) + 1))
v4l2_warn(&sdev->sd,
"%s: device took too much time to answer (%d usec).\n",
__func__, usecs);
"(%s) Device took too much time to answer.\n", __func__);
/* Clear status bits */
err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
NULL, 0,
resp, ARRAY_SIZE(resp),
DEFAULT_TIMEOUT);
for (;;) {
/* Clear status bits */
err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
NULL, 0,
resp, ARRAY_SIZE(resp),
DEFAULT_TIMEOUT);
/* The USB device returns errors when it waits for the
* STC bit to be set. Hence polling */
if (err >= 0) {
v4l2_dbg(1, debug, &sdev->sd,
"%s: status bits: 0x%02x\n", __func__, resp[0]);
if (err < 0)
goto exit;
v4l2_dbg(1, debug, &sdev->sd,
"%s: status bits: 0x%02x\n", __func__, resp[0]);
if (!(resp[0] & SI4713_STC_INT))
err = -EIO;
exit:
return err;
if (resp[0] & SI4713_STC_INT)
return 0;
}
if (jiffies_to_usecs(jiffies - start_jiffies) > usecs)
return err < 0 ? err : -EIO;
/* We sleep here for 3 ms in order to avoid flooding the device
* with USB requests. The si4713 USB driver was developed
* by reverse engineering the Windows USB driver. The windows
* driver also has a ~2.5 ms delay between responses. */
msleep(3);
}
}
/*
@ -1024,7 +1045,6 @@ static int si4713_initialize(struct si4713_device *sdev)
if (rval < 0)
return rval;
sdev->frequency = DEFAULT_FREQUENCY;
sdev->stereo = 1;
sdev->tune_rnl = DEFAULT_TUNE_RNL;