[PATCH] mmc: core: Fix mmc_select_hs200() regression in v4.7-rc.
From: peter.griffin@linaro.org (Peter Griffin)
Date: 2016-06-07 13:57:11
Also in:
linux-mmc, lkml
Hi Lee, On Tue, 07 Jun 2016, Lee Jones wrote:
On Tue, 07 Jun 2016, Peter Griffin wrote:quoted
mmc_select_bus_width() returns bus width (4 or 8) on success or zero if unsupported. If bus width is set successfully we then wish to switch to HS200 mode. This avoids the following error message in v4.70-rc2 [ 2.523674] mmc0: mmc_select_hs200 failed, error 3 [ 2.528516] mmc0: error 3 whilst initialising MMC card With this patch card is enumerated correctly [ 2.468065] mmc0: new HS200 MMC card at address 0001 [ 2.468335] mmcblk0: mmc0:0001 P1XXXX 7.20 GiB [ 2.468441] mmcblk0boot0: mmc0:0001 P1XXXX partition 1 2.00 MiB [ 2.468552] mmcblk0boot1: mmc0:0001 P1XXXX partition 2 2.00 MiB [ 2.468651] mmcblk0rpmb: mmc0:0001 P1XXXX partition 3 128 KiB [ 2.469269] mmcblk0: p1 Fixes: 287980e (remove lots of IS_ERR_VALUE abuses) Signed-off-by: Peter Griffin <peter.griffin@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> --- drivers/mmc/core/mmc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index c984321..aafb73d 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c@@ -1276,7 +1276,7 @@ static int mmc_select_hs200(struct mmc_card *card) * switch to HS200 mode if bus width is set successfully. */ err = mmc_select_bus_width(card); - if (!err) { + if (err > 0) { val = EXT_CSD_TIMING_HS200 | card->drive_strength << EXT_CSD_DRV_STR_SHIFT; err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,@@ -1583,7 +1583,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, } else if (mmc_card_hs(card)) { /* Select the desired bus width optionally */ err = mmc_select_bus_width(card); - if (!err) { + if (err > 0) { err = mmc_select_hs_ddr(card); if (err) goto free_card;Looks like this has already been 'fixed' in -rc2.
Ah, it seems I was on -rc1, not -rc2
quoted hunk ↗ jump to hunk
Although, this patch does not work for me. mmc: fix mmc mode selection for HS-DDR and higher When IS_ERR_VALUE was removed from the mmc core code, it was replaced with a simple not-zero check. This does not work, as the value checked is the return value for mmc_select_bus_width, which returns the set bit width on success. This made eMMC modes higher than HS-DDR unusable. Fix this by checking for a positive return value instead. Fixes: 287980e49ffc ("remove lots of IS_ERR_VALUE abuses") Cc: Arnd Bergmann [off-list ref] Signed-off-by: Chen-Yu Tsai [off-list ref] Acked-by: Hans de Goede [off-list ref] Reviewed-by: Krzysztof Kozlowski [off-list ref] Acked-by: Jaehoon Chung [off-list ref] Reviewed-by: Shawn Lin [off-list ref] Tested-by: Marcel Ziswiler [off-list ref] Tested-by: Bjorn Andersson [off-list ref] Signed-off-by: Ulf Hansson [off-list ref]diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index c984321..5d438ad 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c@@ -1276,7 +1276,7 @@ static int mmc_select_hs200(struct mmc_card *card) * switch to HS200 mode if bus width is set successfully. */ err = mmc_select_bus_width(card); - if (!err) { + if (err >= 0) {
This patch looks wrong to me, as if zero is returned by mmc_select_bus_width() it means setting the bus width failed, and you most likely don't want to switch to hs200 mode. Ulf - what is your opinion? regards, Peter.>