[PATCH v7 0/2] mmc: sdhci-msm: Add support for MSM chipsets

[Georgi Djakov <gdjakov@mm-sol.com>]

This patchset adds basic support of the Secure Digital Host Controller
Interface compliant controller found in Qualcomm MSM chipsets.

Tested with SD card on APQ8074 Dragonboard.

Patchset applies to mmc-next, as it depends on:
4525181 mmc: sdhci: add hooks for platform specific tuning

Changes from v6:
- Fixed wrong pointer in sdhci_msm_pwr_irq().
- Added platform_execute_tuning() callback as the MSM SDHC does not
  support tuning as in SDHC 3.0 spec and will need custom implementation
  in order to support SDR104, HS200 and HS400.
- Removed the always-on devicetree property - if the regulator is
  configured as always-on, it will not be disabled anyway.
- Removed devm_pinctrl_get_select_default() - the default pins are 
  already set from the device core.
- Removed wrapper function sdhci_msm_set_vdd_io_vol() and enum
  vdd_io_level and now calling regulator_set_voltage() directly.
- Converted #defines to use BIT() macro.
- Added IS_ERR(vreg->reg) check at the beginning of sdhci_msm_vreg
  functions.
- Do not print errors when regulators init return -EPROBE_DEFER as the
  deffered init is not an actual error.
- Handle each power irq status bit separately in sdhci_msm_pwr_irq().
- Ensure that any pending power irq is acknowledged before enabling it,
  otherwise the irq handler will be fired prematurely.
- Minor changes.

Changes from v5:
- Driver is split into multiple patches
- Do not initialize variables that are assigned later in code
- Remove some useless comments
- Use shorter variable names
- Change pr_err() to dev_err()
- Optimized sdhci_msm_setup_vreg()
- Some code alignment fixes
- Improved DT values sanity check
- Added dev_dbg print for sdhci controller version in probe()
- Added usleep_range() after SW reset - it can take some time
- Added SDHCI_QUIRK_SINGLE_POWER_WRITE - power handled by PMIC
- Renamed DT property vdd-io to vddio

Changes from v4:
- Simplified sdhci_msm_vreg_disable() and sdhci_msm_set_vdd_io_vol()
- Use devm_ioremap_resource() instead of devm_ioremap()
- Converted IS_ERR_OR_NULL to IS_ERR
- Disable regulators in sdhci_msm_remove()
- Check for DT node at the beginning in sdhci_msm_probe()
- Removed more redundant code
- Changes in some error messages
- Minor fixes

Changes from v3:
- Allocate memory for all required structs at once
- Added termination entry in sdhci_msm_dt_match[]
- Fixed a missing sdhci_pltfm_free() in probe()
- Removed redundant of_match_ptr
- Removed the unneeded function sdhci_msm_vreg_reset()

Changes from v2:
- Added DT bindings for clocks
- Moved voltage regulators data to platform data
- Removed unneeded includes
- Removed obsolete and wrapper functions
- Removed error checking where unnecessary
- Removed redundant _clk suffix from clock names
- Just return instead of goto where possible
- Minor fixes

Changes from v1:
- GPIO references are replaced by pinctrl
- DT parsing is done mostly by mmc_of_parse()
- Use of_match_device() for DT matching
- A few minor changes

Georgi Djakov (2):
  mmc: sdhci-msm: Initial SDHCI MSM driver documentation
  mmc: sdhci-msm: Initial support for MSM chipsets

 .../devicetree/bindings/mmc/sdhci-msm.txt          |   93 +++
 drivers/mmc/host/Kconfig                           |   13 +
 drivers/mmc/host/Makefile                          |    1 +
 drivers/mmc/host/sdhci-msm.c                       |  655 ++++++++++++++++++++
 4 files changed, 762 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mmc/sdhci-msm.txt
 create mode 100644 drivers/mmc/host/sdhci-msm.c

-- 
1.7.9.5