Re: [PATCH 28/40] Input: atmel_mxt_ts - Add CHG line handling in bootloader code

[Benson Leung]

On Fri, Feb 22, 2013 at 9:58 AM, Nick Dyer  wrote:
> The bootloader state machine toggles the CHG/Interrupt line to indicate when
> it has transitioned between states. Waiting for this event improves bootloader
> reliability.
>
> Signed-off-by: Nick Dyer 
> ---
>  drivers/input/touchscreen/atmel_mxt_ts.c |   29 +++--
>  1 file changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c 
> b/drivers/input/touchscreen/atmel_mxt_ts.c
> index a1f196b..f182228 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -430,6 +430,27 @@ static int mxt_probe_bootloader(struct mxt_data *data)
> return 0;
>  }
>
> +static int mxt_wait_for_chg(struct mxt_data *data)
> +{
> +   int timeout_counter = 0;
> +   int count = 1E6;
> +
> +   if (data->pdata->read_chg == NULL) {

This also assumes the existence of data->pdata. If data->pdata ==
NULL, you're going to have a bad time.

> +   msleep(20);
> +   return 0;
> +   }
> +
> +   while ((timeout_counter++ <= count) && data->pdata->read_chg())
> +   udelay(20);
> +
> +   if (timeout_counter > count) {
> +   dev_err(>client->dev, "mxt_wait_for_chg() timeout!\n");
> +   return -EIO;
> +   }
> +
> +   return 0;
> +}
> +

> --
> 1.7.10.4
>



-- 
Benson Leung
Software Engineer, Chrom* OS
ble...@chromium.org
--
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Re: [PATCH 28/40] Input: atmel_mxt_ts - Add CHG line handling in bootloader code

[Benson Leung]

This is very similar to a patch that Daniel and I sent earlier this month.

http://www.spinics.net/lists/linux-input/msg24666.html

The major difference is that your wait_for_chg does a polling read of
chg, while the one we worked on leaves the irq enabled and waits on
completion.

On Fri, Feb 22, 2013 at 9:58 AM, Nick Dyer  wrote:
> The bootloader state machine toggles the CHG/Interrupt line to indicate when
> it has transitioned between states. Waiting for this event improves bootloader
> reliability.
>
> Signed-off-by: Nick Dyer 
> ---
>  drivers/input/touchscreen/atmel_mxt_ts.c |   29 +++--
>  1 file changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c 
> b/drivers/input/touchscreen/atmel_mxt_ts.c
> index a1f196b..f182228 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -430,6 +430,27 @@ static int mxt_probe_bootloader(struct mxt_data *data)
> return 0;
>  }
>
> +static int mxt_wait_for_chg(struct mxt_data *data)
> +{
> +   int timeout_counter = 0;
> +   int count = 1E6;
> +
> +   if (data->pdata->read_chg == NULL) {
> +   msleep(20);
> +   return 0;
> +   }
> +
> +   while ((timeout_counter++ <= count) && data->pdata->read_chg())
> +   udelay(20);
> +
> +   if (timeout_counter > count) {
> +   dev_err(>client->dev, "mxt_wait_for_chg() timeout!\n");
> +   return -EIO;
> +   }
> +
> +   return 0;
> +}
> +
>  static u8 mxt_get_bootloader_version(struct mxt_data *data, u8 val)
>  {
> struct device *dev = >client->dev;
> @@ -478,9 +499,10 @@ recheck:
> val &= ~MXT_BOOT_STATUS_MASK;
> break;
> case MXT_FRAME_CRC_PASS:
> -   if (val == MXT_FRAME_CRC_CHECK)
> +   if (val == MXT_FRAME_CRC_CHECK) {
> +   mxt_wait_for_chg(data);
> goto recheck;
> -   if (val == MXT_FRAME_CRC_FAIL) {
> +   } else if (val == MXT_FRAME_CRC_FAIL) {
> dev_err(dev, "Bootloader CRC fail\n");
> return -EINVAL;
> }
> @@ -1781,6 +1803,7 @@ static int mxt_load_fw(struct device *dev, const char 
> *fn)
>
> ret = mxt_check_bootloader(data, MXT_WAITING_BOOTLOAD_CMD);
> if (ret) {
> +   mxt_wait_for_chg(data);
> /* Bootloader may still be unlocked from previous update
>  * attempt */
> ret = mxt_check_bootloader(data, MXT_WAITING_FRAME_DATA);
> @@ -1800,6 +1823,7 @@ static int mxt_load_fw(struct device *dev, const char 
> *fn)
> }
>
> while (pos < fw->size) {
> +   mxt_wait_for_chg(data);
> ret = mxt_check_bootloader(data, MXT_WAITING_FRAME_DATA);
> if (ret) {
> data->state = FAILED;
> @@ -1818,6 +1842,7 @@ static int mxt_load_fw(struct device *dev, const char 
> *fn)
> goto release_firmware;
> }
>
> +   mxt_wait_for_chg(data);
> ret = mxt_check_bootloader(data, MXT_FRAME_CRC_PASS);
> if (ret) {
> retry++;
> --
> 1.7.10.4
>



--
Benson Leung
Software Engineer, Chrom* OS
ble...@chromium.org
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 28/40] Input: atmel_mxt_ts - Add CHG line handling in bootloader code

[Benson Leung]

This is very similar to a patch that Daniel and I sent earlier this month.

http://www.spinics.net/lists/linux-input/msg24666.html

The major difference is that your wait_for_chg does a polling read of
chg, while the one we worked on leaves the irq enabled and waits on
completion.

On Fri, Feb 22, 2013 at 9:58 AM, Nick Dyer nick.d...@itdev.co.uk wrote:
 The bootloader state machine toggles the CHG/Interrupt line to indicate when
 it has transitioned between states. Waiting for this event improves bootloader
 reliability.

 Signed-off-by: Nick Dyer nick.d...@itdev.co.uk
 ---
  drivers/input/touchscreen/atmel_mxt_ts.c |   29 +++--
  1 file changed, 27 insertions(+), 2 deletions(-)

 diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c 
 b/drivers/input/touchscreen/atmel_mxt_ts.c
 index a1f196b..f182228 100644
 --- a/drivers/input/touchscreen/atmel_mxt_ts.c
 +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
 @@ -430,6 +430,27 @@ static int mxt_probe_bootloader(struct mxt_data *data)
 return 0;
  }

 +static int mxt_wait_for_chg(struct mxt_data *data)
 +{
 +   int timeout_counter = 0;
 +   int count = 1E6;
 +
 +   if (data-pdata-read_chg == NULL) {
 +   msleep(20);
 +   return 0;
 +   }
 +
 +   while ((timeout_counter++ = count)  data-pdata-read_chg())
 +   udelay(20);
 +
 +   if (timeout_counter  count) {
 +   dev_err(data-client-dev, mxt_wait_for_chg() timeout!\n);
 +   return -EIO;
 +   }
 +
 +   return 0;
 +}
 +
  static u8 mxt_get_bootloader_version(struct mxt_data *data, u8 val)
  {
 struct device *dev = data-client-dev;
 @@ -478,9 +499,10 @@ recheck:
 val = ~MXT_BOOT_STATUS_MASK;
 break;
 case MXT_FRAME_CRC_PASS:
 -   if (val == MXT_FRAME_CRC_CHECK)
 +   if (val == MXT_FRAME_CRC_CHECK) {
 +   mxt_wait_for_chg(data);
 goto recheck;
 -   if (val == MXT_FRAME_CRC_FAIL) {
 +   } else if (val == MXT_FRAME_CRC_FAIL) {
 dev_err(dev, Bootloader CRC fail\n);
 return -EINVAL;
 }
 @@ -1781,6 +1803,7 @@ static int mxt_load_fw(struct device *dev, const char 
 *fn)

 ret = mxt_check_bootloader(data, MXT_WAITING_BOOTLOAD_CMD);
 if (ret) {
 +   mxt_wait_for_chg(data);
 /* Bootloader may still be unlocked from previous update
  * attempt */
 ret = mxt_check_bootloader(data, MXT_WAITING_FRAME_DATA);
 @@ -1800,6 +1823,7 @@ static int mxt_load_fw(struct device *dev, const char 
 *fn)
 }

 while (pos  fw-size) {
 +   mxt_wait_for_chg(data);
 ret = mxt_check_bootloader(data, MXT_WAITING_FRAME_DATA);
 if (ret) {
 data-state = FAILED;
 @@ -1818,6 +1842,7 @@ static int mxt_load_fw(struct device *dev, const char 
 *fn)
 goto release_firmware;
 }

 +   mxt_wait_for_chg(data);
 ret = mxt_check_bootloader(data, MXT_FRAME_CRC_PASS);
 if (ret) {
 retry++;
 --
 1.7.10.4




--
Benson Leung
Software Engineer, Chrom* OS
ble...@chromium.org
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH 28/40] Input: atmel_mxt_ts - Add CHG line handling in bootloader code

[Benson Leung]

On Fri, Feb 22, 2013 at 9:58 AM, Nick Dyer nick.d...@itdev.co.uk wrote:
 The bootloader state machine toggles the CHG/Interrupt line to indicate when
 it has transitioned between states. Waiting for this event improves bootloader
 reliability.

 Signed-off-by: Nick Dyer nick.d...@itdev.co.uk
 ---
  drivers/input/touchscreen/atmel_mxt_ts.c |   29 +++--
  1 file changed, 27 insertions(+), 2 deletions(-)

 diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c 
 b/drivers/input/touchscreen/atmel_mxt_ts.c
 index a1f196b..f182228 100644
 --- a/drivers/input/touchscreen/atmel_mxt_ts.c
 +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
 @@ -430,6 +430,27 @@ static int mxt_probe_bootloader(struct mxt_data *data)
 return 0;
  }

 +static int mxt_wait_for_chg(struct mxt_data *data)
 +{
 +   int timeout_counter = 0;
 +   int count = 1E6;
 +
 +   if (data-pdata-read_chg == NULL) {

This also assumes the existence of data-pdata. If data-pdata ==
NULL, you're going to have a bad time.

 +   msleep(20);
 +   return 0;
 +   }
 +
 +   while ((timeout_counter++ = count)  data-pdata-read_chg())
 +   udelay(20);
 +
 +   if (timeout_counter  count) {
 +   dev_err(data-client-dev, mxt_wait_for_chg() timeout!\n);
 +   return -EIO;
 +   }
 +
 +   return 0;
 +}
 +

 --
 1.7.10.4




-- 
Benson Leung
Software Engineer, Chrom* OS
ble...@chromium.org
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/