4.19-stable review patch. If anyone has any objections, please let me know.
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From: Ivan Semenov ivan@semenov.dev
commit ff3206d2186d84e4f77e1378ba1d225633f17b9b upstream.
Initializing an eMMC that's connected via a 1-bit bus is current failing, if the HW (DT) informs that 4-bit bus is supported. In fact this is a regression, as we were earlier capable of falling back to 1-bit mode, when switching to 4/8-bit bus failed. Therefore, let's restore the behaviour.
Log for Samsung eMMC 5.1 chip connected via 1bit bus (only D0 pin) Before patch: [134509.044225] mmc0: switch to bus width 4 failed [134509.044509] mmc0: new high speed MMC card at address 0001 [134509.054594] mmcblk0: mmc0:0001 BGUF4R 29.1 GiB [134509.281602] mmc0: switch to bus width 4 failed [134509.282638] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.282657] Buffer I/O error on dev mmcblk0, logical block 0, async page read [134509.284598] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.284602] Buffer I/O error on dev mmcblk0, logical block 0, async page read [134509.284609] ldm_validate_partition_table(): Disk read failed. [134509.286495] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.286500] Buffer I/O error on dev mmcblk0, logical block 0, async page read [134509.288303] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.288308] Buffer I/O error on dev mmcblk0, logical block 0, async page read [134509.289540] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.289544] Buffer I/O error on dev mmcblk0, logical block 0, async page read [134509.289553] mmcblk0: unable to read partition table [134509.289728] mmcblk0boot0: mmc0:0001 BGUF4R 31.9 MiB [134509.290283] mmcblk0boot1: mmc0:0001 BGUF4R 31.9 MiB [134509.294577] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 [134509.295835] I/O error, dev mmcblk0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 [134509.295841] Buffer I/O error on dev mmcblk0, logical block 0, async page read
After patch:
[134551.089613] mmc0: switch to bus width 4 failed [134551.090377] mmc0: new high speed MMC card at address 0001 [134551.102271] mmcblk0: mmc0:0001 BGUF4R 29.1 GiB [134551.113365] mmcblk0: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 [134551.114262] mmcblk0boot0: mmc0:0001 BGUF4R 31.9 MiB [134551.114925] mmcblk0boot1: mmc0:0001 BGUF4R 31.9 MiB
Fixes: 577fb13199b1 ("mmc: rework selection of bus speed mode") Cc: stable@vger.kernel.org Signed-off-by: Ivan Semenov ivan@semenov.dev Link: https://lore.kernel.org/r/20240206172845.34316-1-ivan@semenov.dev Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mmc/core/mmc.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -994,10 +994,12 @@ static int mmc_select_bus_width(struct m static unsigned ext_csd_bits[] = { EXT_CSD_BUS_WIDTH_8, EXT_CSD_BUS_WIDTH_4, + EXT_CSD_BUS_WIDTH_1, }; static unsigned bus_widths[] = { MMC_BUS_WIDTH_8, MMC_BUS_WIDTH_4, + MMC_BUS_WIDTH_1, }; struct mmc_host *host = card->host; unsigned idx, bus_width = 0;