Commit Graph

593 Commits

Author SHA1 Message Date
Linus Torvalds 894025f24b Merge tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
 "Here is the big set of USB and PHY driver updates for 4.15-rc1.

  There is the usual amount of gadget and xhci driver updates, along
  with phy and chipidea enhancements. There's also a lot of SPDX tags
  and license boilerplate cleanups as well, which provide some churn in
  the diffstat.

  Other major thing is the typec code that moved out of staging and into
  the "real" part of the drivers/usb/ tree, which was nice to see
  happen.

  All of these have been in linux-next with no reported issues for a
  while"

* tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
  usb: gadget: f_fs: Fix use-after-free in ffs_free_inst
  USB: usbfs: compute urb->actual_length for isochronous
  usb: core: message: remember to reset 'ret' to 0 when necessary
  USB: typec: Remove remaining redundant license text
  USB: typec: add SPDX identifiers to some files
  USB: renesas_usbhs: rcar?.h: add SPDX tags
  USB: chipidea: ci_hdrc_tegra.c: add SPDX line
  USB: host: xhci-debugfs: add SPDX lines
  USB: add SPDX identifiers to all remaining Makefiles
  usb: host: isp1362-hcd: remove a couple of redundant assignments
  USB: adutux: remove redundant variable minor
  usb: core: add a new usb_get_ptm_status() helper
  usb: core: add a 'type' parameter to usb_get_status()
  usb: core: introduce a new usb_get_std_status() helper
  usb: core: rename usb_get_status() 'type' argument to 'recip'
  usb: core: add Status Type definitions
  USB: gadget: Remove redundant license text
  USB: gadget: function: Remove redundant license text
  USB: gadget: udc: Remove redundant license text
  USB: gadget: legacy: Remove redundant license text
  ...
2017-11-13 21:14:07 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Greg Kroah-Hartman 4dce3c4b9b Merge tag 'extcon-next-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/extcon into usb-next
Chanwoo writes:

Update extcon for 4.15

Detailed description for this pull request:
1. Split out extcon header file for consumer and provider device
: The extcon has two type of extcon devices as following.
- 'extcon provider deivce' adds new extcon device and detect
the state/properties of external connector. Also, it notifies the
state/properties to the extcon consumer device.
- 'extcon consumer device' gets the change state/properties
from extcon provider device.

Prior to that, include/linux/extcon.h contains all exported API
for both provider and consumer device driver. To clarify the meaning
of header file and to remove the wrong use-case on consumer device.
- include/linux/extcon-provider.h includes API for the provider device driver.
- include/linux/extcon.h includes the API for the consumer device driver.

2. Support the SmartDock accessory on extcon-max77843.c device driver
- Support the SmartDock accessory which detects following connectors
 at the same time.
 : USB host throught USB hub for mouse, keyboard and so on.
 : MHL connector for video output.
 : Charger connector for battery charging.
- It tested with Unitek Y-2165 MHL+OTG Hub Smart Phone Dock.

3. Fix the minor issue of extcon driver
- Delete the unneeded initialization in extcon-max14577.
- Make extcon_info static const in order to fix the warning.
2017-10-27 12:36:06 +02:00
Andrzej Pietrasiewicz 36914111e6 drivers: phy: add calibrate method
Some quirky UDCs (like dwc3 on Exynos) need to have their phys calibrated e.g.
for using super speed. This patch adds a new phy_calibrate() method.
When the calibration should be used is dependent on actual chip.

In case of dwc3 on Exynos the calibration must happen after usb_add_hcd()
(while in host mode), because certain phy parameters like Tx LOS levels
and boost levels need to be calibrated further post initialization of xHCI
controller, to get SuperSpeed operations working. But an hcd must be
prepared first in order to pass it to usb_add_hcd(), so, in particular, dwc3
registers must be available first, and in order for the latter to happen
the phys must be initialized. This poses a chicken and egg problem if
the calibration were to be performed in phy_init(). To break the circular
dependency a separate method is added which can be called at a desired
moment after phy intialization.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:28 +05:30
Vivek Gautam 052553af6a ufs/phy: qcom: Refactor to use phy_init call
Refactor ufs_qcom_power_up_sequence() to get rid of ugly
exported phy APIs and use the phy_init() and phy_power_on()
to do the phy initialization.

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:27 +05:30
Vivek Gautam 3d741ff44e phy: qcom-ufs: Add support to set phy mode
Adding support to set desired UFS phy mode that can be set
from the host controller.

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:27 +05:30
Kishon Vijay Abraham I 2796ceb0c1 phy: ti-pipe3: Update pcie phy settings
Update the PCIe phy settings based on new settings available
in AM572x Technical Reference Manual[1] Revision I, revised
April 2017 in Table 26-62 "Preferred PCIe_PHY_RX SCP Register
Settings".

[1] http://www.ti.com/lit/ug/spruhz6i/spruhz6i.pdf

Cc: Vignesh R <vigneshr@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
[nsekhar@ti.com: commit message updates]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:27 +05:30
Florian Fainelli af174c4956 phy: brcm-sata: Allow RX equalizer tuning
Parse the DT properties brcm,rxaeq-mode and brcm,rxaeq-value to
correctly configure the RX equalizer of the PHY. This may be required to
resolve specific signal integrity issues.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:26 +05:30
Florian Fainelli 6ec248fed5 phy: brcm-sata: Prepare for doing more tuning
Split the functional code in brcm_stb_sata_init() to a separate function
that actually does configure spread spectrum: brcm_stb_sata_ssc_init()
and make that function return void, since that function cannot fail.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:26 +05:30
Yoshihiro Shimoda 9adaaa9e45 phy: rcar-gen3-usb2: add SoC-specific parameter for dedicated pins
This patch adds SoC-specific parameter to avoid reading/writing
specific registers wrongly if this driver runs on a SoC which doesn't
have dedicated pins (e.g. R-Car D3). This patch also changes the
value "has_otg" to "has_otg_pins" for slightly easier reading of
the code.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:26 +05:30
Yoshihiro Shimoda b56acc82f9 phy: rcar-gen3-usb2: use enum phy_mode in the role_store()
This patch modifies the role_store() to use "enum phy_mode" instead
of the local "bool" for host/device mode selection.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:26 +05:30
Yoshihiro Shimoda 7e0540f413 phy: rcar-gen3-usb2: check dr_mode for otg mode
The previous code assumed a channel has otg capability if a channel
has interrupt property. But, it is not good because:
 - Battery charging feature also needs interrupt property.
 - Some R-Car Gen3 SoCs (e.g. R-Car D3) don't have OTG capability.

So, this patch checks whether usb 2.0 host node has dr_mode property or
not. If it has 'dr_mode = "otg";', this driver enables otg capability.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:26 +05:30
Icenowy Zheng a06173badf phy: sun4i-usb: enable PHY0 dual route for V3s SoC
Allwinner V3s SoC also features the dual route of the first USB PHY.

Enable it.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:25 +05:30
Douglas Anderson e023b1fb52 phy: rockchip-typec: Do the calibration more correctly
Calculate the calibration code as per the docs.  The docs talk about
reading and averaging the pullup and pulldown calibration codes.  They
also talk about adding in some adjustment codes.  Let's do what the
docs say.

In practice this doesn't seem to matter a whole lot.  On a device I
tested the pullup and pulldown codes were nearly the same (0x23 and
0x24) and the adjustment codes were 0.

Reviewed-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:25 +05:30
Douglas Anderson f85fd4c909 phy: rockchip-typec: Avoid magic numbers + add delays in aux calib
NOTE: nothing is known to be fixed by this change, but it does enforce
some delays that are documented to be necessary.  Possibly this could
fix some corner cases.

The function tcphy_dp_aux_calibration(), like most of the functions in
the type C PHY, is mostly undocumented and filled with mysterious,
hardcoded numbers.

Let's attempt to try to document some of these numbers and clean the
function up a little bit.  Here's the actual cleanup that happened
here:

1. All magic numbers were replaced with bit definitions.

2. For registers that we modify multiple times I now keep track of the
   value of the register rather than randomly doing a
   read/modify/write or just hardcoding a new number based on knowing
   what the old number was.

3. Delay 10 ms (vs 1 ms) after writing the calibration code.  No idea
   if this is important but it matches the example in the docs.

4. Whenever setting a "delayed" version of a signal always put an
   explicit delay in the code.  No known problems were seen without
   this delay but it seems wise to have it.  Whenever a delay of "at
   least 100 ns" was specified I used a delay of 1 us.

5. Added comments to some of the bits of code.

6. Removed duplicate setting of TX_ANA_CTRL_REG_5 (to 0)

7. Moved setting of TX_ANA_CTRL_REG_3 to the same place it was in the
   sample code.  Note that TX_ANA_CTRL_REG_3 ought to be initted to 0
   (and elsewhere we assume that we just got a reset), but it seems
   fine to be explicit.

8. Treats the calibration code as a 7-bit two's complement number.
   This isn't strictly required, but seems slightly cleaner.  The docs
   say "treat this as a two's complement number, but it should never
   be negative".  If we ever read the "adjustment" codes as documented
   then perhaps the two's complement bit will matter more.

There are still a few weird / mysterious things around aux init and
this doesn't attempt to fix all of them.  Mostly it's aimed at doing
changes that should be _very_ safe and add a lot of clarity.  Things
specifically not done:

A) Resolve the fact that some registers are read/modify/write and
   others are explicitly initted to a value.  We always call
   tcphy_dp_aux_calibration() right after resetting the PHY so it's
   probably not critical, but it's a little weird that the code is
   inconsistent.

B) Fully resolve the documented init sequence with the current one.
   We still have a few mystery steps and we also leave out turning on
   TXDA_DRV_LDO_BG_FB_EN and TXDA_DRV_LDO_BG_REF_EN, which is in the
   sample code.

C) Clean things up to read all the bits of the calibration code.  This
   will hopefully come in a followup change.

This also doesn't attempt to document any of the other parts of the
PHY--just the aux init which is all I got docs for.

Reviewed-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:25 +05:30
Chunfeng Yun 5954a10e8e phy: phy-mtk-tphy: add set_mode callback
This is used to force PHY with USB OTG function to enter a specific
mode, and override OTG IDPIN(or IDDIG) signal.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:25 +05:30
Antoine Tenart 30dbc0415f phy: mvebu-cp110-comphy: remove unused member in private struct
The 'modes' member of the mvebu_comphy_priv structure is not used.
Remove it.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 11:19:25 +05:30
Chanwoo Choi 176aa36012 extcon: Split out extcon header file for consumer and provider device
The extcon has two type of extcon devices as following.
- 'extcon provider deivce' adds new extcon device and detect the
   state/properties of external connector. Also, it notifies the
   state/properties to the extcon consumer device.
- 'extcon consumer device' gets the change state/properties
   from extcon provider device.
Prior to that, include/linux/extcon.h contains all exported API for
both provider and consumer device driver. To clarify the meaning of
header file and to remove the wrong use-case on consumer device,
this patch separates into extcon.h and extcon-provider.h.

[Description for include/linux/{extcon.h|extcon-provider.h}]
- extcon.h includes the extcon API and data structure for extcon consumer
  device driver. This header file contains the following APIs:
  : Register/unregister the notifier to catch the change of extcon device
  : Get the extcon device instance
  : Get the extcon device name
  : Get the state of each external connector
  : Get the property value of each external connector
  : Get the property capability of each external connector

- extcon-provider.h includes the extcon API and data structure for extcon
  provider device driver. This header file contains the following APIs:
  : Include 'include/linux/extcon.h'
  : Allocate the memory for extcon device instance
  : Register/unregister extcon device
  : Set the state of each external connector
  : Set the property value of each external connector
  : Set the property capability of each external connector

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-23 14:07:58 +09:00
Kishon Vijay Abraham I d664817452 Merge branch 'fixes' into next 2017-10-18 16:31:59 +05:30
Douglas Anderson 2fb850092f phy: rockchip-typec: Check for errors from tcphy_phy_init()
The function tcphy_phy_init() could return an error but the callers
weren't checking the return value.  They should.  In at least one case
while testing I saw the message "wait pma ready timeout" which
indicates that tcphy_phy_init() really could return an error and we
should account for it.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-03 15:18:41 +05:30
Al Cooper 415060b21f phy: usb: phy-brcm-usb: Add ability to force DRD mode to host or device
When the usb phy device mode is set to "drd", the USB port will
switch between device and host modes depending on what's plugged
into the port. Customers have asked for the ability to force
host or device mode from software. This commit adds sysfs
entries to the phy device that allow this. The sysfs for the phy
device can be found at:
/sys/bus/platform/drivers/brcmstb-usb-phy/*.usb-phy

The following sysfs entries were added:
- "dr_mode" (RO) - The current phy "dr_mode" setting.
  It will be set to one of the following values:
  - "host" - host mode
  - "peripheral " - device mode
  - "drd" - switch between device and host mode based on
    installed device
  - "typec-pd" - device/host mode is controller by the USB
    Type-C PD protocol.

If "dr_mode" is "drd"
- "drd_select" (RW) -
  It will be set to one of the following values:
  - "host" - force host mode
  - "device" - force device mode
  - "auto" - allow normal auto selection of host/device based on
    inserted USB device

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-03 11:54:55 +05:30
Al Cooper 49859e55e3 phy: usb: phy-brcm-usb: Add Broadcom STB USB phy driver
Add a new USB Phy driver for Broadcom STB SoCs. This driver
supports Broadcom STB ARM SoCs. This driver in
combination with the Broadcom STB ohci, ehci and xhci
drivers will enable USB1.1, USB2.0 and USB3.0 support.
This Phy driver also supports the Broadcom BDC gadget
driver.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-10-03 11:54:54 +05:30
Douglas Anderson 26e03d803c phy: rockchip-typec: Don't set the aux voltage swing to 400 mV
On rk3399-gru-kevin there are some cases where we're seeing AUX CH
failures when trying to do DisplayPort over type C.  Problems are
intermittent and don't reproduce all the time.  Problems are often
bursty and failures persist for several seconds before going away.
The failure case I focused on is:
* A particular type C to HDMI adapter.
* One orientation (flip mode) of that adapter.
* Easier to see failures when something is plugged into the _other
  type C port at the same time.
* Problems reproduce on both type C ports (left and right side).

Ironically problems also stop reproducing when I solder wires onto the
AUX CH signals on a port (even if no scope is connected to the
signals).  In this case, problems only stop reproducing on the port
with the wires connected.

From the above it appears that something about the signaling on the
aux channel is marginal and any slight differences can bring us over
the edge to failure.

It turns out that we can fix our problems by just increasing the
voltage swing of the AUX CH, giving us a bunch of extra margin.  In DP
up to version 1.2 the voltage swing on the aux channel was specced as
.29 V to 1.38 V.  In DP version 1.3 the aux channel voltage was
tightened to be between .29 V and .40 V, but it clarifies that it
really only needs the lower voltage when operating at the highest
speed (HBR3 mode).  So right now we are trying to use a voltage that
technically should be valid for all versions of the spec (including
version 1.3 when transmitting at HBR3).  That would be great to do if
it worked reliably.  ...but it doesn't seem to.

It turns out that if you continue to read through the DP part of the
rk3399 TRM and other parts of the type C PHY spec you'll find out that
while the rk3399 does support DP 1.3, it doesn't support HBR3.  The
docs specifically say "RBR, HBR and HBR2 data rates only".  Thus there
is actually no requirement to support an AUX CH swing of .4 V.

Even if there is no actual requirement to support the tighter voltage
swing, one could possibly argue that we should support it anyway.  The
DP spec clarifies that the lower voltage on the AUX CH will reduce
cross talk in some cases and that seems like it could be beneficial
even at the lower bit rates.  At the moment, though, we are seeing
problems with the AUX CH and not on the other lines.  Also, checking
another known working and similar laptop shows that the other laptop
runs the AUX channel at a higher voltage.

Other notes:
* Looking at measurements done on the AUX CH we weren't actually
  compliant with the DP 1.3 spec anyway.  AUX CH peek-to-peek voltage
  was measured on rk3399-gru-kevin as .466 V which is > .4 V.
* With this new patch the AUX channel isn't actually 1.0 V, but it has
  been confirmed that the signal is better and has more margin.  Eye
  diagram passes.
* If someone were truly an expert in the Type C PHY and in DisplayPort
  signaling they might be able to make things work and keep the
  voltage at < .4 V.  The Type C PHY seems to have a plethora of
  tuning knobs that could almost certainly improve the signal
  integrity.  Some of these things (like enabling tx_fcm_full_margin)
  even seem to fix my problems.  However, lacking expertise I can't
  say whether this is a better or worse solution.  Tightening signals
  to give cleaner waveforms can often have adverse affects, like
  increasing EMI or adding noise to other signals.  I'd rather not
  tune things like this without a healthy application of expertise
  that I don't have.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-09-26 17:02:49 +05:30
Douglas Anderson f98b743875 phy: rockchip-typec: Set the AUX channel flip state earlier
On some DP monitors we found that setting the wrong flip state on the
AUX channel could cause the monitor to stop asserting HotPlug Detect
(HPD).  Setting the right flip state caused these monitors to start
asserting HotPlug Detect again.

Here's what we believe was happening:
* We'd plug in the monitor and we'd see HPD assert
* We'd quickly see HPD deassert
* The kernel would try to init the type C PHY but would init it in USB
  mode (because there was a peripheral there but no HPD)
* Because the kernel never set the flip mode properly we'd never see
  the HPD come back.

With this change, we'll still see HPD disappear (we don't think
there's anything we can do about that), but then it will come back.

Overall we can say that it's sane to set the AUX channel flip state
even when HPD is not asserted.

NOTE: to make this change possible, I needed to do a bit of cleanup to
the tcphy_dp_aux_calibration() function so that it doesn't ever
clobber the FLIP state.  This made it very obvious that a line of code
documented as "setting bit 12" also did a bunch of other magic,
undocumented stuff.  For now I'll just break out the bits and add a
comment that this is black magic and we'll try to document
tcphy_dp_aux_calibration() better in a future CL.

ALSO NOTE: the old function used to write a bunch of hardcoded
values in _some_ cases instead of doing a read-modify-write.  One
could possibly assert that these could have had (beneficial) side
effects and thus with this new code (which always does
read-modify-write) we could have a bug.  We shouldn't need to worry,
though, since in the old code tcphy_dp_aux_calibration() was always
called following the de-assertion of "reset" the the type C PHY.
...so the type C PHY was always in default state.  TX_ANA_CTRL_REG_1
is documented to be 0x0 after reset.  This was also confirmed by
printk.

Suggested-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-09-26 17:02:49 +05:30
Dan Carpenter c1c7acac09 phy: mvebu-cp110: checking for NULL instead of IS_ERR()
devm_ioremap_resource() never returns NULL, it only returns error
pointers so this test needs to be changed.

Fixes: d0438bd6aa ("phy: add the mvebu cp110 comphy driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2017-09-26 17:02:49 +05:30