| Message ID | 1453362769-16223-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, Shawn. On 01/21/2016 04:52 PM, Shawn Lin wrote: > num_slots comes from pdata if existing, otherwise from > dw_mci_parse_dt which make it at least one slot. If > num_slots is less than 1 for the existing pdata case, > current code return -ENODEV. But dw_mci_probe seems to > treat this a optional case as it will call SDMMC_GET_SLOT_NUM > if no slot assigned. Well, we need to consider more thing.. Host can get the number of slot from SDMMC_GET_SLOT_NUM(). But i think this way also has the problem. num_slot isn't defined anywhere, and num_slot should be set to value of SDMMC_GET_SLOT_NUM. If that value is higher than 1, it should be blocking..(I didn't test all cases..) Even though this patch is not correct, i could check the problem relevant to num_slot, because of this patch. :) my suggestion is if pdata->num_slot is not defined anywhere, just set to 1 by default. not take from SDMMC_GET_SLOT_NUM. if (host->pdata->nums_slots < 1 || host->pdata->nums_slots > SDMMC_GET_SLOT_NUM()) This is correct condition. num_slots can't be higher than number of supported slots. how about? Best Regards, Jaehoon Chung > > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > > --- > > drivers/mmc/host/dw_mmc.c | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > index 7128351..a116ec6 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -2949,12 +2949,6 @@ int dw_mci_probe(struct dw_mci *host) > } > } > > - if (host->pdata->num_slots < 1) { > - dev_err(host->dev, > - "Platform data must supply num_slots.\n"); > - return -ENODEV; > - } > - > host->biu_clk = devm_clk_get(host->dev, "biu"); > if (IS_ERR(host->biu_clk)) { > dev_dbg(host->dev, "biu clock not available\n"); > -- 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
On 2016/1/22 10:46, Jaehoon Chung wrote: > Hi, Shawn. > > On 01/21/2016 04:52 PM, Shawn Lin wrote: >> num_slots comes from pdata if existing, otherwise from >> dw_mci_parse_dt which make it at least one slot. If >> num_slots is less than 1 for the existing pdata case, >> current code return -ENODEV. But dw_mci_probe seems to >> treat this a optional case as it will call SDMMC_GET_SLOT_NUM >> if no slot assigned. > > Well, we need to consider more thing.. > Host can get the number of slot from SDMMC_GET_SLOT_NUM(). > But i think this way also has the problem. > > num_slot isn't defined anywhere, and num_slot should be set to value of SDMMC_GET_SLOT_NUM. > If that value is higher than 1, it should be blocking..(I didn't test all cases..) > Actually, from the code itself, it confused me the way about how we get num_slot. At leaset, we might should try to cleanup it someway to make it a little more clear. And just as what you point out, we see some broblem here. > Even though this patch is not correct, i could check the problem relevant to num_slot, because of this patch. :) > Nice to here that. I make it a RFC patch since I also not quite sure about all cases including some corner cases. Let's think it twice. > my suggestion is if pdata->num_slot is not defined anywhere, just set to 1 by default. > not take from SDMMC_GET_SLOT_NUM. > yes, SDMMC_GET_SLOT_NUM is the capability of controller, num_slot is hardware wired number. So, geting it from SDMMC_GET_SLOT_NUM has problem. > if (host->pdata->nums_slots < 1 || > host->pdata->nums_slots > SDMMC_GET_SLOT_NUM()) > > This is correct condition. num_slots can't be higher than number of supported slots. > how about? Seems reasonable. I guess you want to come up with a new patch dealing with it? :) > > Best Regards, > Jaehoon Chung > >> >> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >> >> --- >> >> drivers/mmc/host/dw_mmc.c | 6 ------ >> 1 file changed, 6 deletions(-) >> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >> index 7128351..a116ec6 100644 >> --- a/drivers/mmc/host/dw_mmc.c >> +++ b/drivers/mmc/host/dw_mmc.c >> @@ -2949,12 +2949,6 @@ int dw_mci_probe(struct dw_mci *host) >> } >> } >> >> - if (host->pdata->num_slots < 1) { >> - dev_err(host->dev, >> - "Platform data must supply num_slots.\n"); >> - return -ENODEV; >> - } >> - >> host->biu_clk = devm_clk_get(host->dev, "biu"); >> if (IS_ERR(host->biu_clk)) { >> dev_dbg(host->dev, "biu clock not available\n"); >> > > > >
On 01/22/2016 12:07 PM, Shawn Lin wrote: > On 2016/1/22 10:46, Jaehoon Chung wrote: >> Hi, Shawn. >> >> On 01/21/2016 04:52 PM, Shawn Lin wrote: >>> num_slots comes from pdata if existing, otherwise from >>> dw_mci_parse_dt which make it at least one slot. If >>> num_slots is less than 1 for the existing pdata case, >>> current code return -ENODEV. But dw_mci_probe seems to >>> treat this a optional case as it will call SDMMC_GET_SLOT_NUM >>> if no slot assigned. >> >> Well, we need to consider more thing.. >> Host can get the number of slot from SDMMC_GET_SLOT_NUM(). >> But i think this way also has the problem. >> >> num_slot isn't defined anywhere, and num_slot should be set to value of SDMMC_GET_SLOT_NUM. >> If that value is higher than 1, it should be blocking..(I didn't test all cases..) >> > > Actually, from the code itself, it confused me the way about how we get > num_slot. At leaset, we might should try to cleanup it someway to make > it a little more clear. And just as what you point out, we see some > broblem here. > >> Even though this patch is not correct, i could check the problem relevant to num_slot, because of this patch. :) >> > > Nice to here that. I make it a RFC patch since I also not quite sure > about all cases including some corner cases. Let's think it twice. > >> my suggestion is if pdata->num_slot is not defined anywhere, just set to 1 by default. >> not take from SDMMC_GET_SLOT_NUM. >> > > yes, SDMMC_GET_SLOT_NUM is the capability of controller, num_slot is > hardware wired number. So, geting it from SDMMC_GET_SLOT_NUM has > problem. > >> if (host->pdata->nums_slots < 1 || >> host->pdata->nums_slots > SDMMC_GET_SLOT_NUM()) >> >> This is correct condition. num_slots can't be higher than number of supported slots. >> how about? > > Seems reasonable. > I guess you want to come up with a new patch dealing with it? :) No matter who does this. If you are ok, i will wait for patch. :) Best Regards, Jaehoon Chung > >> >> Best Regards, >> Jaehoon Chung >> >>> >>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >>> >>> --- >>> >>> drivers/mmc/host/dw_mmc.c | 6 ------ >>> 1 file changed, 6 deletions(-) >>> >>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >>> index 7128351..a116ec6 100644 >>> --- a/drivers/mmc/host/dw_mmc.c >>> +++ b/drivers/mmc/host/dw_mmc.c >>> @@ -2949,12 +2949,6 @@ int dw_mci_probe(struct dw_mci *host) >>> } >>> } >>> >>> - if (host->pdata->num_slots < 1) { >>> - dev_err(host->dev, >>> - "Platform data must supply num_slots.\n"); >>> - return -ENODEV; >>> - } >>> - >>> host->biu_clk = devm_clk_get(host->dev, "biu"); >>> if (IS_ERR(host->biu_clk)) { >>> dev_dbg(host->dev, "biu clock not available\n"); >>> >> >> >> >> > > -- 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/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 7128351..a116ec6 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2949,12 +2949,6 @@ int dw_mci_probe(struct dw_mci *host) } } - if (host->pdata->num_slots < 1) { - dev_err(host->dev, - "Platform data must supply num_slots.\n"); - return -ENODEV; - } - host->biu_clk = devm_clk_get(host->dev, "biu"); if (IS_ERR(host->biu_clk)) { dev_dbg(host->dev, "biu clock not available\n");
num_slots comes from pdata if existing, otherwise from dw_mci_parse_dt which make it at least one slot. If num_slots is less than 1 for the existing pdata case, current code return -ENODEV. But dw_mci_probe seems to treat this a optional case as it will call SDMMC_GET_SLOT_NUM if no slot assigned. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> --- drivers/mmc/host/dw_mmc.c | 6 ------ 1 file changed, 6 deletions(-)