Messages in this thread Patch in this message | | | Subject | Re: [PATCH V2 03/27] mmc: mmci: convert dma_setup callback to return an int | From | Ludovic BARRE <> | Date | Mon, 24 Sep 2018 18:12:44 +0200 |
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hi Ulf
On 09/24/2018 04:28 PM, Ulf Hansson wrote: > On 21 September 2018 at 11:45, Ludovic Barre <ludovic.Barre@st.com> wrote: >> From: Ludovic Barre <ludovic.barre@st.com> >> >> This patch converts dma_setup callback to return an integer >> This patch is needed to prepare sdmmc variant with internal dma >> >> Signed-off-by: Ludovic Barre <ludovic.barre@st.com> >> --- >> drivers/mmc/host/mmci.c | 14 ++++++++++---- >> drivers/mmc/host/mmci.h | 2 +- >> drivers/mmc/host/mmci_qcom_dml.c | 6 ++++-- >> 3 files changed, 15 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c >> index cbd67bc..2f845f3 100644 >> --- a/drivers/mmc/host/mmci.c >> +++ b/drivers/mmc/host/mmci.c >> @@ -415,7 +415,7 @@ static void mmci_init_sg(struct mmci_host *host, struct mmc_data *data) >> * no custom DMA interfaces are supported. >> */ >> #ifdef CONFIG_DMA_ENGINE >> -static void mmci_dma_setup(struct mmci_host *host) >> +static int mmci_dma_setup(struct mmci_host *host) >> { >> const char *rxname, *txname; >> >> @@ -466,7 +466,9 @@ static void mmci_dma_setup(struct mmci_host *host) >> } >> >> if (host->ops && host->ops->dma_setup) >> - host->ops->dma_setup(host); >> + return host->ops->dma_setup(host); >> + > > Looks like you need to implement a error handling, instead of just > returning the error code.
yes, today if a dma_setup is defined, we can't fallback to pio mode. A use_dma variable (defined in mmci_host) could be setted follow the return code of ops->dma_setup
example:
void mmci_dma_setup(struct mmci_host *host) { int err;
if (!host->ops || !host->ops->dma_setup) return;
err = host->ops->dma_setup(host); if (err) return; host->use_dma = true; /* initialize pre request cookie */ host->next_cookie = 1; }
use_dma variable could be check by mmci_host_ops variant functions.
are you agree with this proposal?
> >> + return 0; >> } >> >> /* >> @@ -741,8 +743,10 @@ static void mmci_post_request(struct mmc_host *mmc, struct mmc_request *mrq, >> static void mmci_get_next_data(struct mmci_host *host, struct mmc_data *data) >> { >> } >> -static inline void mmci_dma_setup(struct mmci_host *host) >> + >> +static inline int mmci_dma_setup(struct mmci_host *host) >> { >> + return 0; >> } >> >> static inline void mmci_dma_release(struct mmci_host *host) >> @@ -1796,7 +1800,9 @@ static int mmci_probe(struct amba_device *dev, >> amba_rev(dev), (unsigned long long)dev->res.start, >> dev->irq[0], dev->irq[1]); >> >> - mmci_dma_setup(host); >> + ret = mmci_dma_setup(host); >> + if (ret) >> + goto clk_disable; >> >> pm_runtime_set_autosuspend_delay(&dev->dev, 50); >> pm_runtime_use_autosuspend(&dev->dev); >> diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h >> index 21aaf9a..06299ac 100644 >> --- a/drivers/mmc/host/mmci.h >> +++ b/drivers/mmc/host/mmci.h >> @@ -273,7 +273,7 @@ struct variant_data { >> >> /* mmci variant callbacks */ >> struct mmci_host_ops { >> - void (*dma_setup)(struct mmci_host *host); >> + int (*dma_setup)(struct mmci_host *host); >> }; >> >> struct mmci_host_next { >> diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c >> index be3fab5..1bb59cf 100644 >> --- a/drivers/mmc/host/mmci_qcom_dml.c >> +++ b/drivers/mmc/host/mmci_qcom_dml.c >> @@ -119,7 +119,7 @@ static int of_get_dml_pipe_index(struct device_node *np, const char *name) >> } >> >> /* Initialize the dml hardware connected to SD Card controller */ >> -static void qcom_dma_setup(struct mmci_host *host) >> +static int qcom_dma_setup(struct mmci_host *host) >> { >> u32 config; >> void __iomem *base; >> @@ -131,7 +131,7 @@ static void qcom_dma_setup(struct mmci_host *host) >> >> if (producer_id < 0 || consumer_id < 0) { >> host->variant->qcom_dml = false; > > It seems like the existing code is an attempt to fallback to use pio > mode. However, I doubt it works as is.
oops, I seen that like a variant identification issue, so if it's a fallback to pio mode it doesn't work.
> >> - return; >> + return -EINVAL; > > My point is, if you return an error code here, it means that the error > code becomes propagated and ->probe() will fail. > > Ideally, we should be able fall back to pio mode when dma doesn't > work. I have looped in Srinivas who implemented the qcom dml support, > let's see if he can explains the intent with the code. > > I also volunteer to help out running some tests on the 410c platform, > however allow me a day or two to do that.
yes, I would be more reassured
> >> } >> >> base = host->base + DML_OFFSET; >> @@ -175,6 +175,8 @@ static void qcom_dma_setup(struct mmci_host *host) >> >> /* Make sure dml initialization is finished */ >> mb(); >> + >> + return 0; >> } >> >> static struct mmci_host_ops qcom_variant_ops = { >> -- >> 2.7.4 >> > > Kind regards > Uffe >
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