| Message ID | 20191217112625.30715-1-peter.ujfalusi@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mmc: bcm2835: Use dma_request_chan() instead dma_request_slave_channel() | expand |
Hi Peter, On Tue, 2019-12-17 at 13:26 +0200, Peter Ujfalusi wrote: > dma_request_slave_channel() is a wrapper on top of dma_request_chan() > eating up the error code. > > By using dma_request_chan() directly the driver can support deferred > probing against DMA. > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> > --- > drivers/mmc/host/bcm2835.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c > index 99f61fd2a658..3821f159d36d 100644 > --- a/drivers/mmc/host/bcm2835.c > +++ b/drivers/mmc/host/bcm2835.c > @@ -1393,7 +1393,15 @@ static int bcm2835_probe(struct platform_device *pdev) > host->dma_chan = NULL; > host->dma_desc = NULL; > > - host->dma_chan_rxtx = dma_request_slave_channel(dev, "rx-tx"); > + host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); > + if (IS_ERR(host->dma_chan_rxtx)) { > + if (PTR_ERR(host->dma_chan_rxtx) == -EPROBE_DEFER) > + return -EPROBE_DEFER; I think you should 'goto err' here, as you have to free the mmc host structure allocated earlier in the probe function. Other than that the patch looks good to me. Regards, Nicolas
On 17/12/2019 13.37, Nicolas Saenz Julienne wrote: > Hi Peter, > > On Tue, 2019-12-17 at 13:26 +0200, Peter Ujfalusi wrote: >> dma_request_slave_channel() is a wrapper on top of dma_request_chan() >> eating up the error code. >> >> By using dma_request_chan() directly the driver can support deferred >> probing against DMA. >> >> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> >> --- >> drivers/mmc/host/bcm2835.c | 10 +++++++++- >> 1 file changed, 9 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c >> index 99f61fd2a658..3821f159d36d 100644 >> --- a/drivers/mmc/host/bcm2835.c >> +++ b/drivers/mmc/host/bcm2835.c >> @@ -1393,7 +1393,15 @@ static int bcm2835_probe(struct platform_device *pdev) >> host->dma_chan = NULL; >> host->dma_desc = NULL; >> >> - host->dma_chan_rxtx = dma_request_slave_channel(dev, "rx-tx"); >> + host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); >> + if (IS_ERR(host->dma_chan_rxtx)) { >> + if (PTR_ERR(host->dma_chan_rxtx) == -EPROBE_DEFER) >> + return -EPROBE_DEFER; > > I think you should 'goto err' here, as you have to free the mmc host structure > allocated earlier in the probe function. You are right. > Other than that the patch looks good to me. > > Regards, > Nicolas > - Péter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c index 99f61fd2a658..3821f159d36d 100644 --- a/drivers/mmc/host/bcm2835.c +++ b/drivers/mmc/host/bcm2835.c @@ -1393,7 +1393,15 @@ static int bcm2835_probe(struct platform_device *pdev) host->dma_chan = NULL; host->dma_desc = NULL; - host->dma_chan_rxtx = dma_request_slave_channel(dev, "rx-tx"); + host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); + if (IS_ERR(host->dma_chan_rxtx)) { + if (PTR_ERR(host->dma_chan_rxtx) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + /* Ignore errors to fall back to PIO mode */ + host->dma_chan_rxtx = NULL; + } + clk = devm_clk_get(dev, NULL); if (IS_ERR(clk)) {
dma_request_slave_channel() is a wrapper on top of dma_request_chan() eating up the error code. By using dma_request_chan() directly the driver can support deferred probing against DMA. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> --- drivers/mmc/host/bcm2835.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)