Add support for the LiteX SD-Card device, LiteSDCard.
LiteSDCard is a simple SD-Card interface available as part of the LiteX
environment, used with various RISC-V and other FPGA based SoCs.
New in v8:
commit blurbs:
- cosmetic editing of descriptions
- removed `Cc:` lines
drivers/mmc/host/litex_mmc.c:
- fix file header comment (for real, this time)
- add explicit `bits.h` include
- remove `of_match_ptr()` wrapper from around .of_match_table argument
- fix devm ordering issues: use `devm_request_irq()`, which precludes
the need to call `free_irq()` on `probe()` error path or from `remove()`
>New in v7:
>
>drivers/mmc/host/Kconfig:
> - added module name in LiteSDCard Kconfig entry
>
>drivers/mmc/host/litex_mmc.c:
> - fixed comment formatting, ordering, and capitalization throughout
> the entire file
> - sorted header #include statements
> - removed redundant parantheses in readx_poll_timeout() condition
> - explicit handling of readx_poll_timeout() timeout scenarios
> - dev_err() used in litex_mmc_sdcard_wait_done()
> - use memcpy_fromio() to grab command response
> - no need to apply 0xffff mask to a 32-bit value right-shifted by 16
> (host->resp[3])
> - use clamp() instead of min(max(...)...)
> - reworked platform_get_irq_optional() error handling logic
> - no need to explicitly zero host->irq, kzalloc() does that already
> - added missing free_irq() in litex_mmc_probe() error path
> - reordered calls inside litex_mmc_remove() (calling mmc_free_host()
> before free_irq()
>
>>New in v6:
>>
>>drivers/mmc/host/litex_mmc.c:
>> - fix handling of deferred probe vs. platform_get_irq_optional()
>> - don't #ifdef dma_set_mask_and_coherent(), since it automatically
>> does the right thing on both 32- and 64-bit DMA capable arches
>> - remove MMC_CAP2_FULL_PWR_CYCLE, add MMC_CAP2_NO_MMC to list of
>> hardcoded capabilities during litex_mmc_probe()
>> - hardcode mmc->ocr_avail to the full 2.7-3.6V range allowed by the
>> SDCard spec (the LiteSDCard device doesn't accept software
>> configuration)
>>
>>>New in v5:
>>>
>>>MAINTAINERS:
>>>
>>> - picked up a/b Mateusz
>>>
>>>Doc/dt/bindings/mmc/litex,mmc.yaml:
>>>
>>> - picked up r/b Rob, Joel
>>>
>>>drivers/mmc/host/litex_mmc.c:
>>>
>>> - shorten #define constant names (cosmetic, make them less unwieldy)
>>> - picked up r/b Joel
>>>
>>>>New in v4:
>>>>
>>>>Doc/dt/bindings/mmc/litex,mmc.yaml:
>>>>
>>>> - fixed `dt_binding_check` errors uncovered by Rob's script
>>>>
>>>>drivers/mmc/host/litex_mmc.c:
>>>>
>>>> - struct litex_mmc_host fields re-ordered so that `pahole` reports
>>>> no holes in either 32- or 64-bit builds
>>>> - litex_mmc_set_bus_width() now encapsulates check for
>>>> host->is_bus_width_set
>>>> - litex_mmc_request() - factor out dma data setup into separate
>>>> helper function: litex_mmc_do_dma()
>>>>
>>>>>New in v3:
>>>>>
>>>>> MAINTAINERS:
>>>>>
>>>>> - picked up acked-by Joel
>>>>> - added listing for liteeth driver
>>>>> - added Joel as additional co-maintainer (thanks!)
>>>>>
>>>>> Doc/dt/bindings/mmc/litex,mmc.yaml:
>>>>>
>>>>> - picked up r/b Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> in DT
>>>>> bindings document (please let me know if that was premature, and
>>>>> happy to take further review if needed :)
>>>>> - add dedicated DT property for source clock frequency
>>>>>
>>>>> drivers/mmc/host/litex_mmc.c:
>>>>>
>>>>> - fixed function signature (no line split), and naming (litex_mmc_*)
>>>>> - more informative MODULE_AUTHOR() entries
>>>>> - also added matching "Copyright" entries in file header
>>>>> - fixed description in Kconfig
>>>>> - fixed DT documentation
>>>>> - removed magic constants
>>>>> - removed litex_map_status(), have sdcard_wait_done() return *real*
>>>>> error codes directly instead.
>>>>> - streamlined litex_mmc_reponse_len()
>>>>> - call litex_mmc_set_bus_width() only once, and ensure it returns
>>>>> correct error code(s)
>>>>> - use readx_poll_timeout() -- more concise -- instead of
>>>>> read_poll_timeout()
>>>>> - use dev_err() in litex_mmc_send_cmd() (instead of pr_err())
>>>>> - litex_mmc_setclk() will update host->clock before returning
>>>>> - separate irq initialization into its own function,
>>>>> litex_mmc_irq_init()
>>>>> - document rationale for f_min, f_max
>>>>> - use dmam_alloc_coherent(), which simplifies cleanup significantly
>>>>> - large `if (data) { ... }` block in litex_mmc_request() left as-is,
>>>>> there are too many variables shared with the rest of the parent
>>>>> function body to easily separate (e.g., `len`, `transfer`, `direct`).
>>>>> If this is indeed a blocker, I can take another shot at refactoring
>>>>> it in a future revision!
>>>>> - bump dma_set_mask_and_coherent() to 64-bits on suitable
>>>>> architectures
>>>>> - clock source picked up from dedicated DT clock reference property
>>>>> - remove gpio card-detect logic (needs testing and a dt binding
>>>>> example before being eligible for upstream inclusion)
>>>>>
>>>>>> New in v2:
>>>>>> - reword info message in litex_set_clk()
>>>>>> - streamline code in litex_map_status()
>>>>>> - fix typos in Kconfig (thanks Randy Dunlap <rdunlap@xxxxxxxxxxxxx>)
>>>>>> - improvements suggested by Stafford Horne <shorne@xxxxxxxxx>
>>>>>> - allow COMPILE_TEST in Kconfig
>>>>>> - use read_poll_timeout() when waiting for cmd/data/DMA
>>>>>> xfer completion
>>>>>> - include interrupt.h (thanks kernel test robot <lkp@xxxxxxxxx>)
Gabriel Somlo (3):
MAINTAINERS: co-maintain LiteX platform
dt-bindings: mmc: Add bindings for LiteSDCard
mmc: Add driver for LiteX's LiteSDCard interface
.../devicetree/bindings/mmc/litex,mmc.yaml | 72 ++
MAINTAINERS | 9 +-
drivers/mmc/host/Kconfig | 10 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/litex_mmc.c | 666 ++++++++++++++++++
5 files changed, 756 insertions(+), 2 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mmc/litex,mmc.yaml
create mode 100644 drivers/mmc/host/litex_mmc.c
--
2.31.1
