On 10 February 2014 05:07, Jaehoon Chung <jh80.chung@xxxxxxxxxxx> wrote: > Hi, > > On 02/08/2014 03:39 AM, Puthikorn Voravootivat wrote: >> Force host to have erase capacity to enable trim or >> discard feature in supported eMMC device. >> >> Signed-off-by: Puthikorn Voravootivat <puthik@xxxxxxxxxxxx> >> --- >> In mmc_init_queue() before setting up the discard function, mmc driver >> will call mmc_can_erase() which will always return 0 because the host >> erase capacity is not set anywhere. So to enable discard function, we >> need to add erase capacity to the host. >> >> drivers/mmc/host/dw_mmc.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >> index 55cd110..f47f1c1 100644 >> --- a/drivers/mmc/host/dw_mmc.c >> +++ b/drivers/mmc/host/dw_mmc.c >> @@ -55,6 +55,8 @@ >> #define DW_MCI_FREQ_MAX 200000000 /* unit: HZ */ >> #define DW_MCI_FREQ_MIN 400000 /* unit: HZ */ >> >> +#define DW_MCI_DEFAULT_CAPS (MMC_CAP_ERASE) >> + > > This define didn't need. > >> #ifdef CONFIG_MMC_DW_IDMAC >> #define IDMAC_INT_CLR (SDMMC_IDMAC_INT_AI | SDMMC_IDMAC_INT_NI | \ >> SDMMC_IDMAC_INT_CES | SDMMC_IDMAC_INT_DU | \ >> @@ -2371,6 +2373,8 @@ static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host) >> return ERR_PTR(-ENOMEM); >> } >> >> + pdata->caps |= DW_MCI_DEFAULT_CAPS; >> + > I didn't want to enable by default. If it's possible, how about using dt-file? > Well, if need to enable by default, just use the "pdata->caps |= MMC_CAPS_ERASE;" Why not push this one step further; remove MMC_CAPS_ERASE and make it default enabled for all hosts? Kind regards Ulf Hansson > > Best Regards, > Jaehoon Chung >> /* find out number of slots supported */ >> if (of_property_read_u32(dev->of_node, "num-slots", >> &pdata->num_slots)) { >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html