| Message ID | 1481707438-32240-1-git-send-email-tnhuynh@apm.com |
|---|---|
| State | Accepted |
| Headers | show |
On 12/14/2016 11:23 AM, Tin Huynh wrote: > ACPI always sets Tx/Rx FIFO to 32. This configuration will > cause problem if the IP core supports a FIFO size of less than 32. > The driver should read the FIFO size from the IP and select the smaller > one of the two. > > Signed-off-by: Tin Huynh <tnhuynh@apm.com> > > --- > drivers/i2c/busses/i2c-designware-platdrv.c | 31 ++++++++++++++++++++------ > 1 files changed, 24 insertions(+), 7 deletions(-) Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Dec 14, 2016 at 04:23:58PM +0700, Tin Huynh wrote: > ACPI always sets Tx/Rx FIFO to 32. This configuration will > cause problem if the IP core supports a FIFO size of less than 32. > The driver should read the FIFO size from the IP and select the smaller > one of the two. > > Signed-off-by: Tin Huynh <tnhuynh@apm.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2016-12-14 at 16:23 +0700, Tin Huynh wrote: > ACPI always sets Tx/Rx FIFO to 32. This configuration will > cause problem if the IP core supports a FIFO size of less than 32. > The driver should read the FIFO size from the IP and select the > smaller > one of the two. > > Signed-off-by: Tin Huynh <tnhuynh@apm.com> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > drivers/i2c/busses/i2c-designware-platdrv.c | 31 > ++++++++++++++++++++------ > 1 files changed, 24 insertions(+), 7 deletions(-) > > Change from V4: > -Change else condition and add some comments to clarify new approach. > > Change from V3: > -Use uppercase of FIFO instead of lowercase. > -Correct else condition when IP core return 0 of FIFO. > > Change from V2: > -Add a helper function to set FIFO size. > > Change from V1: > -Revert the default 32 for FIFO, read parameter from IP core > and pick the smaller one of the two. > -Correct the title to describe new approach. > > diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c > b/drivers/i2c/busses/i2c-designware-platdrv.c > index 0b42a12..682adc3 100644 > --- a/drivers/i2c/busses/i2c-designware-platdrv.c > +++ b/drivers/i2c/busses/i2c-designware-platdrv.c > @@ -150,6 +150,29 @@ static int i2c_dw_plat_prepare_clk(struct > dw_i2c_dev *i_dev, bool prepare) > return 0; > } > > +static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id) > +{ > + u32 param, tx_fifo_depth, rx_fifo_depth; > + > + /* > + * Try to detect the FIFO depth if not set by interface > driver, > + * the depth could be from 2 to 256 from HW spec. > + */ > + param = i2c_dw_read_comp_param(dev); > + tx_fifo_depth = ((param >> 16) & 0xff) + 1; > + rx_fifo_depth = ((param >> 8) & 0xff) + 1; > + if (!dev->tx_fifo_depth) { > + dev->tx_fifo_depth = tx_fifo_depth; > + dev->rx_fifo_depth = rx_fifo_depth; > + dev->adapter.nr = id; > + } else if (tx_fifo_depth >= 2) { > + dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, > + tx_fifo_depth); > + dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, > + rx_fifo_depth); > + } > +} > + > static int dw_i2c_plat_probe(struct platform_device *pdev) > { > struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev- > >dev); > @@ -246,13 +269,7 @@ static int dw_i2c_plat_probe(struct > platform_device *pdev) > 1000000); > } > > - if (!dev->tx_fifo_depth) { > - u32 param1 = i2c_dw_read_comp_param(dev); > - > - dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; > - dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; > - dev->adapter.nr = pdev->id; > - } > + dw_i2c_set_fifo_size(dev, pdev->id); > > adap = &dev->adapter; > adap->owner = THIS_MODULE;
On Wed, Dec 14, 2016 at 04:23:58PM +0700, Tin Huynh wrote: > ACPI always sets Tx/Rx FIFO to 32. This configuration will > cause problem if the IP core supports a FIFO size of less than 32. > The driver should read the FIFO size from the IP and select the smaller > one of the two. > > Signed-off-by: Tin Huynh <tnhuynh@apm.com> > Applied to for-current, thanks!
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 0b42a12..682adc3 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -150,6 +150,29 @@ static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare) return 0; } +static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id) +{ + u32 param, tx_fifo_depth, rx_fifo_depth; + + /* + * Try to detect the FIFO depth if not set by interface driver, + * the depth could be from 2 to 256 from HW spec. + */ + param = i2c_dw_read_comp_param(dev); + tx_fifo_depth = ((param >> 16) & 0xff) + 1; + rx_fifo_depth = ((param >> 8) & 0xff) + 1; + if (!dev->tx_fifo_depth) { + dev->tx_fifo_depth = tx_fifo_depth; + dev->rx_fifo_depth = rx_fifo_depth; + dev->adapter.nr = id; + } else if (tx_fifo_depth >= 2) { + dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, + tx_fifo_depth); + dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, + rx_fifo_depth); + } +} + static int dw_i2c_plat_probe(struct platform_device *pdev) { struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev); @@ -246,13 +269,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) 1000000); } - if (!dev->tx_fifo_depth) { - u32 param1 = i2c_dw_read_comp_param(dev); - - dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; - dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; - dev->adapter.nr = pdev->id; - } + dw_i2c_set_fifo_size(dev, pdev->id); adap = &dev->adapter; adap->owner = THIS_MODULE;
ACPI always sets Tx/Rx FIFO to 32. This configuration will cause problem if the IP core supports a FIFO size of less than 32. The driver should read the FIFO size from the IP and select the smaller one of the two. Signed-off-by: Tin Huynh <tnhuynh@apm.com> --- drivers/i2c/busses/i2c-designware-platdrv.c | 31 ++++++++++++++++++++------ 1 files changed, 24 insertions(+), 7 deletions(-) Change from V4: -Change else condition and add some comments to clarify new approach. Change from V3: -Use uppercase of FIFO instead of lowercase. -Correct else condition when IP core return 0 of FIFO. Change from V2: -Add a helper function to set FIFO size. Change from V1: -Revert the default 32 for FIFO, read parameter from IP core and pick the smaller one of the two. -Correct the title to describe new approach.