Hi Ulf,
On 19-04-16 11:29, Ulf Hansson wrote:
On 19 April 2016 at 09:12, Olliver Schinagl <oli...@schinagl.nl> wrote:
In patch 81f8a7be66 Hans de Goede added a patch to allow marking an mmc
device as to having an broken HPI implementation. After talking some
with Hans, we now think it is actually the mmc controller that can be
broken and not support broken HPI's.
I don't want us to invent a DT binding for something you *think* is a
HW controller issue.
Have you really excluded that this isn't a software issue? Me
personally haven't been using HPI that much so I can't really tell
about the code robustness from the mmc core (mmc protocol point of
view).
Well this patch goes hand in hand so to speak with the broken-hpi patch
introduced by him, he did most of the investigation. We just discussed
how to handle it and asked me to cook up the patch.
@hans, what do you think?
Kind regards
Uffe
This patch adds a new capability, mmc-broken-hpi, which allows us to
mark a broken hpi implementation on the host level.
Signed-off-by: Olliver Schinagl <oli...@schinagl.nl>
---
drivers/mmc/core/host.c | 2 ++
drivers/mmc/core/mmc.c | 2 +-
include/linux/mmc/host.h | 1 +
3 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 6e4c55a..9b63b36 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -270,6 +270,8 @@ int mmc_of_parse(struct mmc_host *host)
host->caps |= MMC_CAP_HW_RESET;
if (of_property_read_bool(np, "cap-sdio-irq"))
host->caps |= MMC_CAP_SDIO_IRQ;
+ if (of_property_read_bool(np, "mmc-broken-hpi"))
+ host->caps |= MMC_CAP_BROKEN_HPI;
if (of_property_read_bool(np, "full-pwr-cycle"))
host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
if (of_property_read_bool(np, "keep-power-in-suspend"))
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 4dbe3df..9a19562 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1592,7 +1592,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
/*
* Enable HPI feature (if supported)
*/
- if (card->ext_csd.hpi) {
+ if (card->ext_csd.hpi && !(host->caps & MMC_CAP_BROKEN_HPI)) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_HPI_MGMT, 1,
card->ext_csd.generic_cmd6_time);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 8dd4d29..20f758e 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -264,6 +264,7 @@ struct mmc_host {
#define MMC_CAP_DRIVER_TYPE_A (1 << 23) /* Host supports Driver Type A
*/
#define MMC_CAP_DRIVER_TYPE_C (1 << 24) /* Host supports Driver Type C
*/
#define MMC_CAP_DRIVER_TYPE_D (1 << 25) /* Host supports Driver Type D
*/
+#define MMC_CAP_BROKEN_HPI (1 << 29) /* Host support for HPI is
broken */
#define MMC_CAP_CMD23 (1 << 30) /* CMD23 supported. */
#define MMC_CAP_HW_RESET (1 << 31) /* Hardware reset */
--
2.8.0.rc3
