On Mon, Jul 4, 2016 at 1:40 PM, Lukas Wunner lukas@wunner.de wrote:
Convert asciidoc-formatted docs to rst in accordance with Jonathan's and Jani's effort to use sphinx for kernel-doc rendering in 4.8.
Darren, I'm fine with this one. FWIW: Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com
Cc: Jonathan Corbet corbet@lwn.net Cc: Jani Nikula jani.nikula@intel.com Signed-off-by: Lukas Wunner lukas@wunner.de
drivers/platform/x86/apple-gmux.c | 55 +++++++++++++++++++++------------------ 1 file changed, 29 insertions(+), 26 deletions(-)
diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 4034d2d..a66be13 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -31,19 +31,21 @@ /**
- DOC: Overview
- gmux is a microcontroller built into the MacBook Pro to support dual GPUs:
- A {1}[Lattice XP2] on pre-retinas, a {2}[Renesas R4F2113] on retinas.
- A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on retinas.
- (The MacPro6,1 2013 also has a gmux, however it is unclear why since it has
- dual GPUs but no built-in display.)
- gmux is connected to the LPC bus of the southbridge. Its I/O ports are
- accessed differently depending on the microcontroller: Driver functions
- to access a pre-retina gmux are infixed `_pio_`, those for a retina gmux
- are infixed `_index_`.
- to access a pre-retina gmux are infixed ``_pio_``, those for a retina gmux
- are infixed ``_index_``.
- .. _Lattice XP2:
http://www.latticesemi.com/en/Products/FPGAandCPLD/LatticeXP2.aspx
- .. _Renesas R4F2113:
*/
http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jspstruct apple_gmux_data { @@ -272,15 +274,15 @@ static bool gmux_is_indexed(struct apple_gmux_data *gmux_data) /**
- DOC: Backlight control
- On single GPU MacBooks, the PWM signal for the backlight is generated by
- the GPU. On dual GPU MacBook Pros by contrast, either GPU may be suspended
- to conserve energy. Hence the PWM signal needs to be generated by a separate
- backlight driver which is controlled by gmux. The earliest generation
- MBP5 2008/09 uses a {3}[TI LP8543] backlight driver. All newer models
- use a {4}[TI LP8545].
- MBP5 2008/09 uses a `TI LP8543`_ backlight driver. All newer models
- use a `TI LP8545`_.
- .. _TI LP8543: http://www.ti.com/lit/ds/symlink/lp8543.pdf
*/
- .. _TI LP8545: http://www.ti.com/lit/ds/symlink/lp8545.pdf
static int gmux_get_brightness(struct backlight_device *bd) @@ -312,28 +314,20 @@ static const struct backlight_ops gmux_bl_ops = { /**
- DOC: Graphics mux
- On pre-retinas, the LVDS outputs of both GPUs feed into gmux which muxes
- either of them to the panel. One of the tricks gmux has up its sleeve is
- to lengthen the blanking interval of its output during a switch to
- synchronize it with the GPU switched to. This allows for a flicker-free
- switch that is imperceptible by the user ({5}[US 8,687,007 B2]).
- switch that is imperceptible by the user (`US 8,687,007 B2`_).
- On retinas, muxing is no longer done by gmux itself, but by a separate
- chip which is controlled by gmux. The chip is triple sourced, it is
- either an {6}[NXP CBTL06142], {7}[TI HD3SS212] or {8}[Pericom PI3VDP12412].
- either an `NXP CBTL06142`_, `TI HD3SS212`_ or `Pericom PI3VDP12412`_.
- The panel is driven with eDP instead of LVDS since the pixel clock
- required for retina resolution exceeds LVDS' limits.
- Pre-retinas are able to switch the panel's DDC pins separately.
- This is handled by a {9}[TI SN74LV4066A] which is controlled by gmux.
- This is handled by a `TI SN74LV4066A`_ which is controlled by gmux.
- The inactive GPU can thus probe the panel's EDID without switching over
- the entire panel. Retinas lack this functionality as the chips used for
- eDP muxing are incapable of switching the AUX channel separately (see
@@ -344,15 +338,15 @@ static const struct backlight_ops gmux_bl_ops = {
- The external DP port is only fully switchable on the first two unibody
- MacBook Pro generations, MBP5 2008/09 and MBP6 2010. This is done by an
- {6}[NXP CBTL06141] which is controlled by gmux. It's the predecessor of the
- `NXP CBTL06141`_ which is controlled by gmux. It's the predecessor of the
- eDP mux on retinas, the difference being support for 2.7 versus 5.4 Gbit/s.
- The following MacBook Pro generations replaced the external DP port with a
- combined DP/Thunderbolt port and lost the ability to switch it between GPUs,
- connecting it either to the discrete GPU or the Thunderbolt controller.
- Oddly enough, while the full port is no longer switchable, AUX and HPD
- are still switchable by way of an {10}[NXP CBTL03062] (on pre-retinas
- MBP8 2011 and MBP9 2012) or two {11}[TI TS3DS10224] (on retinas) under the
- are still switchable by way of an `NXP CBTL03062`_ (on pre-retinas
- MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on retinas) under the
- control of gmux. Since the integrated GPU is missing the main link,
- external displays appear to it as phantoms which fail to link-train.
@@ -365,10 +359,19 @@ static const struct backlight_ops gmux_bl_ops = {
- of this feature.
- gmux' initial switch state on bootup is user configurable via the EFI
- variable `gpu-power-prefs-fa4ce28d-b62f-4c99-9cc3-6815686e30f9` (5th byte,
- variable ``gpu-power-prefs-fa4ce28d-b62f-4c99-9cc3-6815686e30f9`` (5th byte,
- 1 = IGD, 0 = DIS). Based on this setting, the EFI firmware tells gmux to
- switch the panel and the external DP connector and allocates a framebuffer
- for the selected GPU.
- .. _US 8,687,007 B2: http://pimg-fpiw.uspto.gov/fdd/07/870/086/0.pdf
- .. _NXP CBTL06141: http://www.nxp.com/documents/data_sheet/CBTL06141.pdf
- .. _NXP CBTL06142: http://www.nxp.com/documents/data_sheet/CBTL06141.pdf
- .. _TI HD3SS212: http://www.ti.com/lit/ds/symlink/hd3ss212.pdf
- .. _Pericom PI3VDP12412: https://www.pericom.com/assets/Datasheets/PI3VDP12412.pdf
- .. _TI SN74LV4066A: http://www.ti.com/lit/ds/symlink/sn74lv4066a.pdf
*/
- .. _TI TS3DS10224: http://www.ti.com/lit/ds/symlink/ts3ds10224.pdf
static void gmux_read_switch_state(struct apple_gmux_data *gmux_data)
2.8.1
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