Re: [PATCH v5] Staging: comedi: convert while loop to timeout in ni_mio_common.c
On 2014-01-15 05:15, Chase Southwood wrote: This patch for ni_mio_common.c changes out a while loop for a timeout, which is preferred. Signed-off-by: Chase Southwood --- All right, I think this guy's ready to go now! Thanks for all the help! Chase 2: Changed from simple clean-up to swapping a timeout in for a while loop. 3: Removed extra counter variable, and added error checking. 4: No longer using counter variable, using jiffies instead. 5: udelay for 10u, instead of 1u. drivers/staging/comedi/drivers/ni_mio_common.c | 11 ++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index 457b884..07e9777 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -687,12 +687,21 @@ static void ni_clear_ai_fifo(struct comedi_device *dev) { const struct ni_board_struct *board = comedi_board(dev); struct ni_private *devpriv = dev->private; + unsigned long timeout; if (board->reg_type == ni_reg_6143) { /* Flush the 6143 data FIFO */ ni_writel(0x10, AIFIFO_Control_6143); /* Flush fifo */ ni_writel(0x00, AIFIFO_Control_6143); /* Flush fifo */ - while (ni_readl(AIFIFO_Status_6143) & 0x10) ; /* Wait for complete */ + /* Wait for complete */ + timeout = jiffies + msec_to_jiffies(500); + while (ni_readl(AIFIFO_Status_6143) & 0x10) { + if (time_after(jiffies, timeout)) { + comedi_error(dev, "FIFO flush timeout."); + break; + } + udelay(10); I preferred the earlier udelay(1) from your PATCH v4, but I think it's even better to replace it with: cpu_relax(); You might also need: #include to define cpu_relax(). + } } else { devpriv->stc_writew(dev, 1, ADC_FIFO_Clear); if (board->reg_type == ni_reg_625x) { -- -=( Ian Abbott @ MEV Ltd.E-mail: )=- -=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=- -- 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 v5] Staging: comedi: convert while loop to timeout in ni_mio_common.c
On 2014-01-15 05:15, Chase Southwood wrote: This patch for ni_mio_common.c changes out a while loop for a timeout, which is preferred. Signed-off-by: Chase Southwood chase.southw...@yahoo.com --- All right, I think this guy's ready to go now! Thanks for all the help! Chase 2: Changed from simple clean-up to swapping a timeout in for a while loop. 3: Removed extra counter variable, and added error checking. 4: No longer using counter variable, using jiffies instead. 5: udelay for 10u, instead of 1u. drivers/staging/comedi/drivers/ni_mio_common.c | 11 ++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index 457b884..07e9777 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -687,12 +687,21 @@ static void ni_clear_ai_fifo(struct comedi_device *dev) { const struct ni_board_struct *board = comedi_board(dev); struct ni_private *devpriv = dev-private; + unsigned long timeout; if (board-reg_type == ni_reg_6143) { /* Flush the 6143 data FIFO */ ni_writel(0x10, AIFIFO_Control_6143); /* Flush fifo */ ni_writel(0x00, AIFIFO_Control_6143); /* Flush fifo */ - while (ni_readl(AIFIFO_Status_6143) 0x10) ; /* Wait for complete */ + /* Wait for complete */ + timeout = jiffies + msec_to_jiffies(500); + while (ni_readl(AIFIFO_Status_6143) 0x10) { + if (time_after(jiffies, timeout)) { + comedi_error(dev, FIFO flush timeout.); + break; + } + udelay(10); I preferred the earlier udelay(1) from your PATCH v4, but I think it's even better to replace it with: cpu_relax(); You might also need: #include asm/processor.h to define cpu_relax(). + } } else { devpriv-stc_writew(dev, 1, ADC_FIFO_Clear); if (board-reg_type == ni_reg_625x) { -- -=( Ian Abbott @ MEV Ltd.E-mail: abbo...@mev.co.uk)=- -=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=- -- 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/
[PATCH v5] Staging: comedi: convert while loop to timeout in ni_mio_common.c
This patch for ni_mio_common.c changes out a while loop for a timeout, which is preferred. Signed-off-by: Chase Southwood --- All right, I think this guy's ready to go now! Thanks for all the help! Chase 2: Changed from simple clean-up to swapping a timeout in for a while loop. 3: Removed extra counter variable, and added error checking. 4: No longer using counter variable, using jiffies instead. 5: udelay for 10u, instead of 1u. drivers/staging/comedi/drivers/ni_mio_common.c | 11 ++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index 457b884..07e9777 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -687,12 +687,21 @@ static void ni_clear_ai_fifo(struct comedi_device *dev) { const struct ni_board_struct *board = comedi_board(dev); struct ni_private *devpriv = dev->private; + unsigned long timeout; if (board->reg_type == ni_reg_6143) { /* Flush the 6143 data FIFO */ ni_writel(0x10, AIFIFO_Control_6143); /* Flush fifo */ ni_writel(0x00, AIFIFO_Control_6143); /* Flush fifo */ - while (ni_readl(AIFIFO_Status_6143) & 0x10) ; /* Wait for complete */ + /* Wait for complete */ + timeout = jiffies + msec_to_jiffies(500); + while (ni_readl(AIFIFO_Status_6143) & 0x10) { + if (time_after(jiffies, timeout)) { + comedi_error(dev, "FIFO flush timeout."); + break; + } + udelay(10); + } } else { devpriv->stc_writew(dev, 1, ADC_FIFO_Clear); if (board->reg_type == ni_reg_625x) { -- 1.8.4.2 -- 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/
[PATCH v5] Staging: comedi: convert while loop to timeout in ni_mio_common.c
This patch for ni_mio_common.c changes out a while loop for a timeout, which is preferred. Signed-off-by: Chase Southwood chase.southw...@yahoo.com --- All right, I think this guy's ready to go now! Thanks for all the help! Chase 2: Changed from simple clean-up to swapping a timeout in for a while loop. 3: Removed extra counter variable, and added error checking. 4: No longer using counter variable, using jiffies instead. 5: udelay for 10u, instead of 1u. drivers/staging/comedi/drivers/ni_mio_common.c | 11 ++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c index 457b884..07e9777 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -687,12 +687,21 @@ static void ni_clear_ai_fifo(struct comedi_device *dev) { const struct ni_board_struct *board = comedi_board(dev); struct ni_private *devpriv = dev-private; + unsigned long timeout; if (board-reg_type == ni_reg_6143) { /* Flush the 6143 data FIFO */ ni_writel(0x10, AIFIFO_Control_6143); /* Flush fifo */ ni_writel(0x00, AIFIFO_Control_6143); /* Flush fifo */ - while (ni_readl(AIFIFO_Status_6143) 0x10) ; /* Wait for complete */ + /* Wait for complete */ + timeout = jiffies + msec_to_jiffies(500); + while (ni_readl(AIFIFO_Status_6143) 0x10) { + if (time_after(jiffies, timeout)) { + comedi_error(dev, FIFO flush timeout.); + break; + } + udelay(10); + } } else { devpriv-stc_writew(dev, 1, ADC_FIFO_Clear); if (board-reg_type == ni_reg_625x) { -- 1.8.4.2 -- 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/