| Message ID | 87k35mkcgu.wl%kuninori.morimoto.gx@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2 September 2014 04:01, Kuninori Morimoto <kuninori.morimoto.gx@gmail.com> wrote: > From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> > > Current mmc block.c has MMC_CAP2_NO_MULTI_READ flag > for HW bug workaround, but it should be implemented > under driver, not framework. > This patch is prepare for it I like the idea of this patchset! Still, historically, we have been using MMC_CAP* to solve these kind issues. Therefore I think the commit message deserves a better explanation to why we invent a new host ops function pointer for this particular case. > > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> > --- > v1 -> v2 > > - no change > > drivers/mmc/card/block.c | 5 +++++ > include/linux/mmc/host.h | 4 ++++ > 2 files changed, 9 insertions(+) > > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index ede41f0..e946067 100644 > --- a/drivers/mmc/card/block.c > +++ b/drivers/mmc/card/block.c > @@ -1402,6 +1402,11 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, > if (card->host->caps2 & MMC_CAP2_NO_MULTI_READ && > rq_data_dir(req) == READ) > brq->data.blocks = 1; > + > + /* Some controllers needs workaround */ Suggest to rephrase the comment to: "Some controllers have HW issues while operating in multiple I/O mode." > + if (card->host->ops->blk_size_workaround) Do you mind renaming the new callback to "multi_io_quirk"? I think it better describes what it's intended for. > + brq->data.blocks = card->host->ops->blk_size_workaround( > + card, req, brq->data.blocks); We shouldn't pass "req" as an argument, since that is a blkdev specific struct. It's better to pass MMC_DATA_WRITE|READ as an unsigned int. > } > > if (brq->data.blocks > 1 || do_rel_wr) { > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index 4cbf614..95bd903 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -139,6 +139,10 @@ struct mmc_host_ops { > int (*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv); > void (*hw_reset)(struct mmc_host *host); > void (*card_event)(struct mmc_host *host); > + > + /* optional callback for mmc block HW bug workaround */ Please update the comment to something like below: "Optional callback to support controllers with HW issues for multiple I/O. Returns the number of supported blocks for the request." > + int (*blk_size_workaround)(struct mmc_card *card, > + struct request *req, int blk_size); > }; > > struct mmc_card; > -- > 1.7.9.5 > Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Ulf > > Current mmc block.c has MMC_CAP2_NO_MULTI_READ flag > > for HW bug workaround, but it should be implemented > > under driver, not framework. > > This patch is prepare for it > > I like the idea of this patchset! > > Still, historically, we have been using MMC_CAP* to solve these kind > issues. Therefore I think the commit message deserves a better > explanation to why we invent a new host ops function pointer for this > particular case. Thank you for your feedback. (Especially "English comment/naming" feedback is very useful for me :) I send v3 patchset soon Best regards --- Kuninori Morimoto -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index ede41f0..e946067 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -1402,6 +1402,11 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, if (card->host->caps2 & MMC_CAP2_NO_MULTI_READ && rq_data_dir(req) == READ) brq->data.blocks = 1; + + /* Some controllers needs workaround */ + if (card->host->ops->blk_size_workaround) + brq->data.blocks = card->host->ops->blk_size_workaround( + card, req, brq->data.blocks); } if (brq->data.blocks > 1 || do_rel_wr) { diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 4cbf614..95bd903 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -139,6 +139,10 @@ struct mmc_host_ops { int (*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv); void (*hw_reset)(struct mmc_host *host); void (*card_event)(struct mmc_host *host); + + /* optional callback for mmc block HW bug workaround */ + int (*blk_size_workaround)(struct mmc_card *card, + struct request *req, int blk_size); }; struct mmc_card;