| Message ID | 1415972879-26509-1-git-send-email-ludovic.desroches@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 14, 2014 at 02:47:59PM +0100, Ludovic Desroches wrote: > Return probe defer if requesting a dma channel without a dma controller probed. > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > drivers/i2c/busses/i2c-at91.c | 22 ++++++++++++++++------ > 1 file changed, 16 insertions(+), 6 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c > index 77fb647..df3f4c4 100644 > --- a/drivers/i2c/busses/i2c-at91.c > +++ b/drivers/i2c/busses/i2c-at91.c > @@ -679,14 +679,21 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) > dma_cap_zero(mask); > dma_cap_set(DMA_SLAVE, mask); > > - dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata, > - dev->dev, "tx"); > - if (!dma->chan_tx) { > + dma->chan_tx = dma_request_slave_channel_reason(dev->dev, "tx"); Will it cause regressions if you drop the compat-version of requesting a channel? > + if (IS_ERR(dma->chan_tx)) { > + ret = PTR_ERR(dma->chan_tx); > + if (ret == -EPROBE_DEFER) { > + dev_warn(dev->dev, "no DMA channel available at the moment\n"); I'd say drop this warning. The core usually prints when deferred probing takes place.
On Wed, Nov 19, 2014 at 10:16:47AM +0100, Wolfram Sang wrote: > On Fri, Nov 14, 2014 at 02:47:59PM +0100, Ludovic Desroches wrote: > > Return probe defer if requesting a dma channel without a dma controller probed. > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > --- > > drivers/i2c/busses/i2c-at91.c | 22 ++++++++++++++++------ > > 1 file changed, 16 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c > > index 77fb647..df3f4c4 100644 > > --- a/drivers/i2c/busses/i2c-at91.c > > +++ b/drivers/i2c/busses/i2c-at91.c > > @@ -679,14 +679,21 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) > > dma_cap_zero(mask); > > dma_cap_set(DMA_SLAVE, mask); > > > > - dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata, > > - dev->dev, "tx"); > > - if (!dma->chan_tx) { > > + dma->chan_tx = dma_request_slave_channel_reason(dev->dev, "tx"); > > Will it cause regressions if you drop the compat-version of requesting > a channel? All our devices with a DMA controller have been converted to device tree and the legacy board support will be removed in 3.19 so it won't cause regression. > > > + if (IS_ERR(dma->chan_tx)) { > > + ret = PTR_ERR(dma->chan_tx); > > + if (ret == -EPROBE_DEFER) { > > + dev_warn(dev->dev, "no DMA channel available at the moment\n"); > > I'd say drop this warning. The core usually prints when deferred probing > takes place. > Ok, I'll remove it. Ludovic
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index 77fb647..df3f4c4 100644 --- a/drivers/i2c/busses/i2c-at91.c +++ b/drivers/i2c/busses/i2c-at91.c @@ -679,14 +679,21 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); - dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata, - dev->dev, "tx"); - if (!dma->chan_tx) { + dma->chan_tx = dma_request_slave_channel_reason(dev->dev, "tx"); + if (IS_ERR(dma->chan_tx)) { + ret = PTR_ERR(dma->chan_tx); + if (ret == -EPROBE_DEFER) { + dev_warn(dev->dev, "no DMA channel available at the moment\n"); + return ret; + } dev_err(dev->dev, "can't get a DMA channel for tx\n"); - ret = -EBUSY; goto error; } + /* + * No reason to check EPROBE_DEFER here since we have already request + * tx channel. If it fails here, it's for another reason. + */ dma->chan_rx = dma_request_slave_channel_compat(mask, filter, pdata, dev->dev, "rx"); if (!dma->chan_rx) { @@ -722,7 +729,7 @@ error: dev_info(dev->dev, "can't use DMA\n"); if (dma->chan_rx) dma_release_channel(dma->chan_rx); - if (dma->chan_tx) + if (!IS_ERR(dma->chan_tx)) dma_release_channel(dma->chan_tx); return ret; } @@ -788,8 +795,11 @@ static int at91_twi_probe(struct platform_device *pdev) clk_prepare_enable(dev->clk); if (dev->pdata->has_dma_support) { - if (at91_twi_configure_dma(dev, phy_addr) == 0) + rc = at91_twi_configure_dma(dev, phy_addr); + if (rc == 0) dev->use_dma = true; + else if (rc == -EPROBE_DEFER) + return rc; } rc = of_property_read_u32(dev->dev->of_node, "clock-frequency",
Return probe defer if requesting a dma channel without a dma controller probed. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> --- drivers/i2c/busses/i2c-at91.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-)