Dinesh, Hi
On Fri, Aug 30, 2013 at 7:28 AM, Dinesh Ram <dinram@xxxxxxxxx> wrote:
>
> 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 <dinram@xxxxxxxxx>
> ---
> drivers/media/radio/si4713/si4713.c | 110 ++++++++++++++++++++----------------
> drivers/media/radio/si4713/si4713.h | 1 +
> 2 files changed, 63 insertions(+), 48 deletions(-)
>
> diff --git a/drivers/media/radio/si4713/si4713.c b/drivers/media/radio/si4713/si4713.c
> index ac727e3..55c4d27 100644
> --- a/drivers/media/radio/si4713/si4713.c
> +++ b/drivers/media/radio/si4713/si4713.c
> @@ -27,7 +27,6 @@
> #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>
> @@ -213,6 +212,7 @@ 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 +228,39 @@ 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;
Why did you change the semantics here?
> }
>
> + 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;
Again?
> + }
>
> - 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 +353,15 @@ 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,
> };
>
> @@ -369,18 +379,22 @@ 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),
> TIMEOUT_POWER_UP);
> -
> +
Please, do not insert tabulation in blank lines.
> if (!err) {
> v4l2_dbg(1, debug, &sdev->sd, "Powerup response: 0x%02x\n",
> resp[0]);
> 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))
> @@ -447,7 +461,7 @@ static int si4713_checkrev(struct si4713_device *sdev)
> if (rval < 0)
> return rval;
>
> - if (resp[1] == SI4713_PRODUCT_NUMBER) {
> + if (resp[1] == SI4713_PRODUCT_NUMBER) {
Please, do not insert spaces in the end of the line.
> v4l2_info(&sdev->sd, "chip found @ 0x%02x (%s)\n",
> client->addr << 1, client->adapter->name);
> } else {
> @@ -465,33 +479,34 @@ 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];
> -
> - /* Wait response from STC interrupt */
> - if (!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;
> + unsigned long start_jiffies = jiffies;
> + int err;
> +
> + 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.\n", __func__);
> +
> + for (;;) {
> + /* Clear status bits */
> + err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
> + NULL, 0,
> + resp, ARRAY_SIZE(resp),
> + DEFAULT_TIMEOUT);
> +
> + if (err >= 0) {
Why are you polling while the command fails? If the command fails, you
need to stop, and propagate the error to upper layers. You shall keep
polling only while the command succeed and (resp[0] & SI4713_STC_INT)
== 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 -EIO;
> + msleep(3);
> + }
Can you please add a comment why you chose msleep(3)? For instance,
here you sleep for 3 ms, in send command you need only 1ms. Any
explanation?
Besides could you please move this for to another function? Something
like si4713_poll_stc?
> }
>
> /*
> @@ -1024,7 +1039,6 @@ 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;
> diff --git a/drivers/media/radio/si4713/si4713.h b/drivers/media/radio/si4713/si4713.h
> index c274e1f..dc0ce66 100644
> --- a/drivers/media/radio/si4713/si4713.h
> +++ b/drivers/media/radio/si4713/si4713.h
> @@ -15,6 +15,7 @@
> #ifndef SI4713_I2C_H
> #define SI4713_I2C_H
>
> +#include <linux/regulator/consumer.h>
> #include <media/v4l2-subdev.h>
> #include <media/v4l2-ctrls.h>
> #include <media/si4713.h>
> --
> 1.8.4.rc2
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Eduardo Bezerra Valentin
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
