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@xxxxxxx>
---
drivers/media/radio/si4713/si4713.c | 108 +++++++++++++++++++++--------------
1 file changed, 64 insertions(+), 44 deletions(-)
diff --git a/drivers/media/radio/si4713/si4713.c b/drivers/media/radio/si4713/si4713.c
index ac727e3..24ae41d 100644
--- a/drivers/media/radio/si4713/si4713.c
+++ b/drivers/media/radio/si4713/si4713.c
@@ -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;
+ }
+
+ DBG_BUFFER(&sdev->sd, "Response", response, respn);
+ if (!check_command_failed(response[0]))
+ return 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);
-
- /* Clear status bits */
- err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
- NULL, 0,
- resp, ARRAY_SIZE(resp),
- DEFAULT_TIMEOUT);
-
- 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;
+ "(%s) Device took too much time to answer.\n", __func__);
+
+ 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 (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;
--
1.7.9.5
--
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