[PATCH v4 00/18] Add suspend to ram support for PCIe on J7200

[Thomas Richard <thomas.richard@xxxxxxxxxxx>]

This add suspend to ram support for the PCIe (RC mode) on J7200 platform.

In RC mode, the reset pin for endpoints is managed by a gpio expander on a
i2c bus. This pin shall be managed in suspend_noirq() and resume_noirq().
The suspend/resume has been moved to suspend_noirq()/resume_noirq() for
pca953x (expander) and pinctrl-single.

To do i2c accesses during suspend_noirq/resume_noirq, we need to force the
wakeup of the i2c controller (which is autosuspended) during suspend
callback. 
It's the only way to wakeup the controller if it's autosuspended, as
runtime pm is disabled in suspend_noirq and resume_noirq.

The main change in the v4 is that now mux_chip_resume() returns zero or on
the first error.
The 2 patches on the pinctrl-single driver were squashed.
And the subject line for the PCI patches was fixed.
Other changes are detailed below.

Regards,

Thomas

Signed-off-by: Thomas Richard <thomas.richard@xxxxxxxxxxx>
---
Changes in v4:
- all: use SoB/Co-developed-by for patches initially developed by Théo
  Lebrun.
- pinctrl-single: squash the two commits.
- i2c-omap: fix line lenghts of the comment in omap_i2c_suspend().
- mux: mux_chip_resume() return 0 or at the first error.
- phy-j721e-wiz: clean code around dev_err_probe().
- phy-j721e-wiz: use REF_CLK_100MHZ macros.
- pci: fix subject line for all PCI patches.
- pci-cadence: use fsleep() instead of usleep_range().
- pci-cadence: remove cdns_torrent_clk_cleanup() call in
  cdns_torrent_phy_resume_noirq().
- pci-j721e: add a patch to use dev_err_probe() instead of dev_err() in the probe().
- pci-j721e: fix unordered header files.
- pci-j721e: remove some log spammers.
- pci-j721e: add a missing clock disable in j721e_pcie_resume_noirq().
- pci-j721e: simplify the patch "Add reset GPIO to struct j721e_pcie"
- Link to v3: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v3-0-5c2e4a3fac1f@xxxxxxxxxxx

Changes in v3:
- pinctrl-single: split patch in two parts, a first patch to remove the
  dead code, a second to move suspend()/resume() callbacks to noirq.
- i2c-omap: add a comments above the suspend_noirq() callback.
- mux: now mux_chip_resume() try to restores all muxes, then return 0 if
  all is ok or the first failure.
- mmio: fix commit message.
- phy-j721e-wiz: add a patch to use dev_err_probe() instead of dev_err() in
  the wiz_clock_init() function.
- phy-j721e-wiz: remove probe boolean for the wiz_clock_init(), rename the
  function to wiz_clock_probe(), extract hardware configuration part in a
  new function wiz_clock_init().
- phy-cadence-torrent: use dev_err_probe() and fix commit messages
- pcie-cadence-host: remove probe boolean for the cdns_pcie_host_setup()
  function and extract the link setup part in a new function
  cdns_pcie_host_link_setup().
- pcie-cadence-host: make cdns_pcie_host_init() global.
- pci-j721e: use the cdns_pcie_host_link_setup() cdns_pcie_host_init()
  functions in the resume_noirq() callback.
- Link to v2: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v2-0-8e4f7d228ec2@xxxxxxxxxxx

Changes in v2:
- all: fix commits messages.
- all: use DEFINE_NOIRQ_DEV_PM_OPS and pm_sleep_ptr macros.
- all: remove useless #ifdef CONFIG_PM.
- pinctrl-single: drop dead code
- mux: add mux_chip_resume() function in mux core.
- mmio: resume sequence is now a call to mux_chip_resume().
- phy-cadence-torrent: fix typo in resume sequence (reset_control_assert()
  instead of reset_control_put()).
- phy-cadence-torrent: use PHY instead of phy.
- pci-j721e: do not shadow cdns_pcie_host_setup return code in resume
  sequence.
- pci-j721e: drop dead code.
- Link to v1: https://lore.kernel.org/r/20240102-j7200-pcie-s2r-v1-0-84e55da52400@xxxxxxxxxxx

---
Thomas Richard (15):
      gpio: pca953x: move suspend()/resume() to suspend_noirq()/resume_noirq()
      pinctrl: pinctrl-single: move suspend()/resume() callbacks to noirq
      i2c: omap: wakeup the controller during suspend() callback
      mux: add mux_chip_resume() function
      phy: ti: phy-j721e-wiz: use dev_err_probe() instead of dev_err()
      phy: ti: phy-j721e-wiz: split wiz_clock_init() function
      phy: ti: phy-j721e-wiz: add resume support
      phy: cadence-torrent: extract calls to clk_get from cdns_torrent_clk
      phy: cadence-torrent: register resets even if the phy is already configured
      phy: cadence-torrent: add already_configured to struct cdns_torrent_phy
      phy: cadence-torrent: remove noop_ops phy operations
      phy: cadence-torrent: add suspend and resume support
      PCI: cadence: Extract link setup sequence from cdns_pcie_host_setup()
      PCI: cadence: Set cdns_pcie_host_init() global
      PCI: j721e: Use dev_err_probe() in the probe() function

Théo Lebrun (3):
      mux: mmio: add resume support
      PCI: j721e: Add reset GPIO to struct j721e_pcie
      PCI: j721e: Add suspend and resume support

 drivers/gpio/gpio-pca953x.c                        |   7 +-
 drivers/i2c/busses/i2c-omap.c                      |  22 ++++
 drivers/mux/core.c                                 |  29 +++++
 drivers/mux/mmio.c                                 |  12 ++
 drivers/pci/controller/cadence/pci-j721e.c         | 107 +++++++++++++++--
 drivers/pci/controller/cadence/pcie-cadence-host.c |  44 ++++---
 drivers/pci/controller/cadence/pcie-cadence.h      |  12 ++
 drivers/phy/cadence/phy-cadence-torrent.c          | 120 ++++++++++++++-----
 drivers/phy/ti/phy-j721e-wiz.c                     | 132 +++++++++++++--------
 drivers/pinctrl/pinctrl-single.c                   |  28 ++---
 include/linux/mux/driver.h                         |   1 +
 11 files changed, 384 insertions(+), 130 deletions(-)
---
base-commit: e76807cc177efce5bdb253de3c673b13c08be013
change-id: 20240102-j7200-pcie-s2r-ecb1a979e357

Best regards,
-- 
Thomas Richard <thomas.richard@xxxxxxxxxxx>