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Author SHA1 Message Date
Tian Tao 291a81c3b0 mmc: meson-mx-sdio: replace spin_lock_irqsave by spin_lock in hard IRQ 
The code has been in a irq-disabled context since it is hard IRQ. There
is no necessity to do it again.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/1604375323-33556-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2020-11-16 11:59:29 +01:00
Douglas Anderson a1a489197a mmc: Set PROBE_PREFER_ASYNCHRONOUS for drivers that existed in v4.19 
This is like commit 3d3451124f3d ("mmc: sdhci-msm: Prefer asynchronous
probe") but applied to a whole pile of drivers.  This batch converts
the drivers that appeared to be around in the v4.19 timeframe.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200903162412.4.I84eb3e0a738635d524c90d1a688087bc295f7c32@changeid
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2020-09-07 14:24:21 +02:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword 
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
 2020-08-23 17:36:59 -05:00
Ulf Hansson 1be64c7963 mmc: host: Drop redundant MMC_CAP_ERASE 
The MMC_CAP_ERASE bit is no longer used by the mmc core as erase, discard
and trim operations are now always supported. Therefore, drop the bit and
move all mmc hosts away from using it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Link: https://lore.kernel.org/r/20200508112902.23575-1-ulf.hansson@linaro.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
 2020-05-28 11:22:14 +02:00
Martin Blumenstingl 91995b904e mmc: meson-mx-sdio: trigger a soft reset after a timeout or CRC error 
The vendor driver (from the 3.10 kernel) triggers a soft reset every
time before starting a new command. While this fixes a problem where
SDIO cards are not detected at all (because all commands simply
timed out) this hurts SD card read performance a bit (in my tests
between 10% to 20%).

Trigger a soft reset after we got a CRC error or if the previous command
timed out (just like the vendor driver from the same 3.10 kernel for the
newer SDHC controller IP does). This fixes detection of SDIO cards and
doesn't hurt SD card read performance at the same time.

With this patch the initialization of an RTL8723BS SDIO card looks like
this:
  req done (CMD52): -110: 00000000 00000000 00000000 00000000
  clock 400000Hz busmode 2 powermode 2 cs 1 Vdd 21 width 1 timing 0
  starting CMD0 arg 00000000 flags 000000c0
  req done (CMD0): 0: 00000000 00000000 00000000 00000000
  clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 0
  starting CMD8 arg 000001aa flags 000002f5
  req done (CMD8): -110: 00000000 00000000 00000000 00000000
  starting CMD5 arg 00000000 flags 000002e1
  req done (CMD5): 0: 90ff0000 00000000 00000000 00000000
  starting CMD5 arg 00200000 flags 000002e1
  req done (CMD5): 0: 90ff0000 00000000 00000000 00000000
  starting CMD3 arg 00000000 flags 00000075
  req done (CMD3): 0: 00010000 00000000 00000000 00000000
  starting CMD7 arg 00010000 flags 00000015
  req done (CMD7): 0: 00001e00 00000000 00000000 00000000
  starting CMD52 arg 00000000 flags 00000195
  req done (CMD52): 0: 00001032 00000000 00000000 00000000
  [... more CMD52 omitted ...]
  clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 2
  clock 50000000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 1 timing 2
  starting CMD52 arg 00000e00 flags 00000195
  req done (CMD52): 0: 00001000 00000000 00000000 00000000
  starting CMD52 arg 80000e02 flags 00000195
  req done (CMD52): 0: 00001002 00000000 00000000 00000000
  clock 50000000Hz busmode 2 powermode 2 cs 0 Vdd 21 width 4 timing 2
  starting CMD52 arg 00020000 flags 00000195
  req done (CMD52): 0: 00001007 00000000 00000000 00000000
  [... more CMD52 omitted ...]
  new high speed SDIO card at address 0001

Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20200503222805.2668941-1-martin.blumenstingl@googlemail.com
Tested-by: Tobias Baumann <017623705678@o2online.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2020-05-28 11:21:42 +02:00
Martin Blumenstingl ddca1092c4 mmc: meson-mx-sdio: remove the broken ->card_busy() op 
The recent commit 0d84c3e6a5 ("mmc: core: Convert to
mmc_poll_for_busy() for erase/trim/discard") makes use of the
->card_busy() op for SD cards. This uncovered that the ->card_busy() op
in the Meson SDIO driver was never working right:
while polling the busy status with ->card_busy()
meson_mx_mmc_card_busy() reads only one of the two MESON_MX_SDIO_IRQC
register values 0x1f001f10 or 0x1f003f10. This translates to "three out
of four DAT lines are HIGH" and "all four DAT lines are HIGH", which
is interpreted as "the card is busy".

It turns out that no situation can be observed where all four DAT lines
are LOW, meaning the card is not busy anymore. Upon further research the
3.10 vendor driver for this controller does not implement the
->card_busy() op.

Remove the ->card_busy() op from the meson-mx-sdio driver since it is
not working. At the time of writing this patch it is not clear what's
needed to make the ->card_busy() implementation work with this specific
controller hardware. For all use-cases which have previously worked the
MMC_CAP_WAIT_WHILE_BUSY flag is now taking over, even if we don't have
a ->card_busy() op anymore.

Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200416183513.993763-3-martin.blumenstingl@googlemail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2020-04-20 09:24:39 +02:00
Martin Blumenstingl e53b868b3c mmc: meson-mx-sdio: Set MMC_CAP_WAIT_WHILE_BUSY 
The Meson SDIO controller uses the DAT0 lane for hardware busy
detection. Set MMC_CAP_WAIT_WHILE_BUSY accordingly. This fixes
the following error observed with Linux 5.7 (pre-rc-1):
  mmc1: Card stuck being busy! __mmc_poll_for_busy
  blk_update_request: I/O error, dev mmcblk1, sector 17111080 op
   0x3:(DISCARD) flags 0x0 phys_seg 1 prio class 0

Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200416183513.993763-2-martin.blumenstingl@googlemail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2020-04-20 09:24:39 +02:00
Yangtao Li e10e54a6c5 mmc: meson-mx-sdio: convert to devm_platform_ioremap_resource 
Use devm_platform_ioremap_resource() to simplify code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Link: https://lore.kernel.org/r/20191215175120.3290-3-tiny.windzz@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2019-12-18 14:46:06 +01:00
Joe Perches 665e985c2f mmc: meson-mx-sdio: Fix misuse of GENMASK macro 
Arguments are supposed to be ordered high then low.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic
Meson8 and Meson8b SoCs")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2019-07-22 15:09:23 +02:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 2019-05-30 11:26:32 -07:00
Stephen Boyd 62e59c4e69 clk: Remove io.h from clk-provider.h 
Now that we've gotten rid of clk_readl() we can remove io.h from the
clk-provider header and push out the io.h include to any code that isn't
already including the io.h header but using things like readl/writel,
etc.

Found with this grep:

  git grep -l clk-provider.h | grep '.c$' | xargs git grep -L 'linux/io.h' | \
  	xargs git grep -l \
	-e '\<__iowrite32_copy\>' --or \
	-e '\<__ioread32_copy\>' --or \
	-e '\<__iowrite64_copy\>' --or \
	-e '\<ioremap_page_range\>' --or \
	-e '\<ioremap_huge_init\>' --or \
	-e '\<arch_ioremap_pud_supported\>' --or \
	-e '\<arch_ioremap_pmd_supported\>' --or \
	-e '\<devm_ioport_map\>' --or \
	-e '\<devm_ioport_unmap\>' --or \
	-e '\<IOMEM_ERR_PTR\>' --or \
	-e '\<devm_ioremap\>' --or \
	-e '\<devm_ioremap_nocache\>' --or \
	-e '\<devm_ioremap_wc\>' --or \
	-e '\<devm_iounmap\>' --or \
	-e '\<devm_ioremap_release\>' --or \
	-e '\<devm_memremap\>' --or \
	-e '\<devm_memunmap\>' --or \
	-e '\<__devm_memremap_pages\>' --or \
	-e '\<pci_remap_cfgspace\>' --or \
	-e '\<arch_has_dev_port\>' --or \
	-e '\<arch_phys_wc_add\>' --or \
	-e '\<arch_phys_wc_del\>' --or \
	-e '\<memremap\>' --or \
	-e '\<memunmap\>' --or \
	-e '\<arch_io_reserve_memtype_wc\>' --or \
	-e '\<arch_io_free_memtype_wc\>' --or \
	-e '\<__io_aw\>' --or \
	-e '\<__io_pbw\>' --or \
	-e '\<__io_paw\>' --or \
	-e '\<__io_pbr\>' --or \
	-e '\<__io_par\>' --or \
	-e '\<__raw_readb\>' --or \
	-e '\<__raw_readw\>' --or \
	-e '\<__raw_readl\>' --or \
	-e '\<__raw_readq\>' --or \
	-e '\<__raw_writeb\>' --or \
	-e '\<__raw_writew\>' --or \
	-e '\<__raw_writel\>' --or \
	-e '\<__raw_writeq\>' --or \
	-e '\<readb\>' --or \
	-e '\<readw\>' --or \
	-e '\<readl\>' --or \
	-e '\<readq\>' --or \
	-e '\<writeb\>' --or \
	-e '\<writew\>' --or \
	-e '\<writel\>' --or \
	-e '\<writeq\>' --or \
	-e '\<readb_relaxed\>' --or \
	-e '\<readw_relaxed\>' --or \
	-e '\<readl_relaxed\>' --or \
	-e '\<readq_relaxed\>' --or \
	-e '\<writeb_relaxed\>' --or \
	-e '\<writew_relaxed\>' --or \
	-e '\<writel_relaxed\>' --or \
	-e '\<writeq_relaxed\>' --or \
	-e '\<readsb\>' --or \
	-e '\<readsw\>' --or \
	-e '\<readsl\>' --or \
	-e '\<readsq\>' --or \
	-e '\<writesb\>' --or \
	-e '\<writesw\>' --or \
	-e '\<writesl\>' --or \
	-e '\<writesq\>' --or \
	-e '\<inb\>' --or \
	-e '\<inw\>' --or \
	-e '\<inl\>' --or \
	-e '\<outb\>' --or \
	-e '\<outw\>' --or \
	-e '\<outl\>' --or \
	-e '\<inb_p\>' --or \
	-e '\<inw_p\>' --or \
	-e '\<inl_p\>' --or \
	-e '\<outb_p\>' --or \
	-e '\<outw_p\>' --or \
	-e '\<outl_p\>' --or \
	-e '\<insb\>' --or \
	-e '\<insw\>' --or \
	-e '\<insl\>' --or \
	-e '\<outsb\>' --or \
	-e '\<outsw\>' --or \
	-e '\<outsl\>' --or \
	-e '\<insb_p\>' --or \
	-e '\<insw_p\>' --or \
	-e '\<insl_p\>' --or \
	-e '\<outsb_p\>' --or \
	-e '\<outsw_p\>' --or \
	-e '\<outsl_p\>' --or \
	-e '\<ioread8\>' --or \
	-e '\<ioread16\>' --or \
	-e '\<ioread32\>' --or \
	-e '\<ioread64\>' --or \
	-e '\<iowrite8\>' --or \
	-e '\<iowrite16\>' --or \
	-e '\<iowrite32\>' --or \
	-e '\<iowrite64\>' --or \
	-e '\<ioread16be\>' --or \
	-e '\<ioread32be\>' --or \
	-e '\<ioread64be\>' --or \
	-e '\<iowrite16be\>' --or \
	-e '\<iowrite32be\>' --or \
	-e '\<iowrite64be\>' --or \
	-e '\<ioread8_rep\>' --or \
	-e '\<ioread16_rep\>' --or \
	-e '\<ioread32_rep\>' --or \
	-e '\<ioread64_rep\>' --or \
	-e '\<iowrite8_rep\>' --or \
	-e '\<iowrite16_rep\>' --or \
	-e '\<iowrite32_rep\>' --or \
	-e '\<iowrite64_rep\>' --or \
	-e '\<__io_virt\>' --or \
	-e '\<pci_iounmap\>' --or \
	-e '\<virt_to_phys\>' --or \
	-e '\<phys_to_virt\>' --or \
	-e '\<ioremap_uc\>' --or \
	-e '\<ioremap\>' --or \
	-e '\<__ioremap\>' --or \
	-e '\<iounmap\>' --or \
	-e '\<ioremap\>' --or \
	-e '\<ioremap_nocache\>' --or \
	-e '\<ioremap_uc\>' --or \
	-e '\<ioremap_wc\>' --or \
	-e '\<ioremap_wc\>' --or \
	-e '\<ioremap_wt\>' --or \
	-e '\<ioport_map\>' --or \
	-e '\<ioport_unmap\>' --or \
	-e '\<ioport_map\>' --or \
	-e '\<ioport_unmap\>' --or \
	-e '\<xlate_dev_kmem_ptr\>' --or \
	-e '\<xlate_dev_mem_ptr\>' --or \
	-e '\<unxlate_dev_mem_ptr\>' --or \
	-e '\<virt_to_bus\>' --or \
	-e '\<bus_to_virt\>' --or \
	-e '\<memset_io\>' --or \
	-e '\<memcpy_fromio\>' --or \
	-e '\<memcpy_toio\>'

I also reordered a couple includes when they weren't alphabetical and
removed clk.h from kona, replacing it with clk-provider.h because
that driver doesn't use clk consumer APIs.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: John Crispin <john@phrozen.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
 2019-05-15 13:21:37 -07:00
Nicholas Mc Guire b0d06f1cb0 mmc: meson-mx-sdio: check devm_kasprintf for failure 
devm_kasprintf() may return NULL on failure of internal allocation thus
the assignments to  init.name  are not safe if not checked. On error
meson_mx_mmc_register_clks() returns negative values so -ENOMEM in the
(unlikely) failure case of devm_kasprintf() should be fine here.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2018-12-17 08:26:24 +01:00
Gustavo A. R. Silva d2681cd81b mmc: meson-mx-sdio: mark expected switch fall-through 
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Notice that in this particular case, I replaced the "fall-through:"
comment with a proper "fall through", which is what GCC is
expecting to find.

Addresses-Coverity-ID: 1373880 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2018-10-08 11:40:43 +02:00
Johan Hovold c483a5cc9d mmc: meson-mx-sdio: fix OF child-node lookup 
Use the new of_get_compatible_child() helper to lookup the slot child
node instead of using of_find_compatible_node(), which searches the
entire tree from a given start node and thus can return an unrelated
(i.e. non-child) node.

This also addresses a potential use-after-free (e.g. after probe
deferral) as the tree-wide helper drops a reference to its first
argument (i.e. the node of the device being probed).

While at it, also fix up the related slot-node reference leak.

Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Cc: stable <stable@vger.kernel.org>     # 4.15
Cc: Carlo Caione <carlo@endlessm.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2018-09-05 08:28:45 +02:00
Kees Cook 2ee4f62005 mmc: Convert timers to use timer_setup() 
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Nicolas Pitre <nico@fluxnic.net>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Bruce Chang <brucechang@via.com.tw>
Cc: Harald Welte <HaraldWelte@viatech.com>
Cc: Tony Olech <tony.olech@elandigitalsystems.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Cc: Arvind Yadav <arvind.yadav.cs@gmail.com>
Cc: Allen <allen.lkml@gmail.com>
Cc: linux-mmc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-omap@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2017-11-02 15:20:28 +01:00
Wolfram Sang aa5754c7d1 mmc: meson-mx-sdio: catch all errors when getting regulators 
Bail out everytime when mmc_regulator_get_supply() returns an errno, not
only when probing gets deferred. This is currently a no-op, because this
function only returns -EPROBE_DEFER or 0 right now. But if it will throw
another error somewhen, it will be for a reason. (This still doesn't change
that getting regulators is optional, so 0 can still mean no regulators
found). So, let us a) be future proof and b) have driver code which is
easier to understand.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2017-10-30 11:50:34 +01:00
Dan Carpenter 2f129d39ad mmc: meson-mx-sdio: Cleanup IS_ERR() checks 
Using PTR_ERR_OR_ZERO() instead of IS_ERR() works, but it's not how
you're supposed to write these conditions.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2017-10-30 11:50:31 +01:00
Dan Carpenter 7599b84932 mmc: meson-mx-sdio: return correct error code 
This has a copy and paste bug so we use "host->fixed_factor_clk" which
is a valid pointer instead of "host->cfg_div_clk" which holds the error
code.

Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2017-10-30 11:49:42 +01:00
Carlo Caione ed80a13bb4 mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoCs 
Add a driver for the SDIO/MMC host found on the Amlogic Meson SoCs. This
is an MMC controller which provides an interface between the application
processor and various memory cards. It supports the SD specification
v2.0 and the eMMC specification v4.41.

The controller provides an internal "mux" which allows connecting up to
three MMC devices to it. Only one device can be used at a time though
since the registers are shared across all devices. The driver takes care
of synchronizing access (similar to the dw_mmc driver).
The maximum supported bus-width is 4-bits.

Amlogic's GPL kernel sources call the corresponding driver "aml_sdio" to
differentiate it from the other MMC controller in (at least the Meson8
and Meson8b) the SoCs (they call the other drivers aml_sdhc and
aml_sdhc_m8, which seem to support a bus-width of up to 8-bits). This
means that there are three different MMC host controller IP blocks from
Amlogic (each of them with completely own register layout and features):
- "SDIO": 1 and 4 bit bus width, support for high-speed modes up to
  UHS-I SDR50, part of Meson6, Meson8 and Meson8b (the driver from this
  patch targets this controller)
- "SDHC": 1, 4 and 8 bit bus width, compatible with standard iNAND
  interface, support for speeds up to HS200 and MMC spec up to version
  4.5x, part of Meson8 and Meson8b SoCs (there is no mainline driver
  for this controller yet)
- "SDEMMC": 1, 4 and 8 bit bus width, support for speeds up to HS400
  and MMC spec up to version 5.0, part of the Meson GX (64-bit) SoCs
  (supported by the meson-gx MMC host driver)

Signed-off-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
 2017-10-30 11:46:02 +01:00