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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-25 05:21:02 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-25 05:21:02 +0300
commit93a4b1b9465d92e8be031b57166afa3d5611e142 (patch)
tree0ac95e35f24a754e01bdc40c56d71068eed49e4c /Documentation/pinctrl.txt
parentd59b92f93df2d545d87d2341eb0705cc926ea22a (diff)
parentdaecdc66968f122fe53038ded8cb7abe93e0aa8c (diff)
downloadlinux-93a4b1b9465d92e8be031b57166afa3d5611e142.tar.xz
Merge tag 'pinctrl-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij: "Here is the bulk of pin control changes for the v4.2 series: Quite a lot of new SoC subdrivers and two new main drivers this time, apart from that business as usual. Details: Core functionality: - Enable exclusive pin ownership: it is possible to flag a pin controller so that GPIO and other functions cannot use a single pin simultaneously. New drivers: - NXP LPC18xx System Control Unit pin controller - Imagination Pistachio SoC pin controller New subdrivers: - Freescale i.MX7d SoC - Intel Sunrisepoint-H PCH - Renesas PFC R8A7793 - Renesas PFC R8A7794 - Mediatek MT6397, MT8127 - SiRF Atlas 7 - Allwinner A33 - Qualcomm MSM8660 - Marvell Armada 395 - Rockchip RK3368 Cleanups: - A big cleanup of the Marvell MVEBU driver rectifying it to correspond to reality - Drop platform device probing from the SH PFC driver, we are now a DT only shop for SuperH - Drop obsolte multi-platform check for SH PFC - Various janitorial: constification, grammar etc Improvements: - The AT91 GPIO portions now supports the set_multiple() feature - Split out SPI pins on the Xilinx Zynq - Support DTs without specific function nodes in the i.MX driver" * tag 'pinctrl-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (99 commits) pinctrl: rockchip: add support for the rk3368 pinctrl: rockchip: generalize perpin driver-strength setting pinctrl: sh-pfc: r8a7794: add SDHI pin groups pinctrl: sh-pfc: r8a7794: add MMCIF pin groups pinctrl: sh-pfc: add R8A7794 PFC support pinctrl: make pinctrl_register() return proper error code pinctrl: mvebu: armada-39x: add support for Armada 395 variant pinctrl: mvebu: armada-39x: add missing SATA functions pinctrl: mvebu: armada-39x: add missing PCIe functions pinctrl: mvebu: armada-38x: add ptp functions pinctrl: mvebu: armada-38x: add ua1 functions pinctrl: mvebu: armada-38x: add nand functions pinctrl: mvebu: armada-38x: add sata functions pinctrl: mvebu: armada-xp: add dram functions pinctrl: mvebu: armada-xp: add nand rb function pinctrl: mvebu: armada-xp: add spi1 function pinctrl: mvebu: armada-39x: normalize ref clock naming pinctrl: mvebu: armada-xp: rename spi to spi0 pinctrl: mvebu: armada-370: align spi1 clock pin naming pinctrl: mvebu: armada-370: align VDD cpu-pd pin naming with datasheet ...
Diffstat (limited to 'Documentation/pinctrl.txt')
-rw-r--r--Documentation/pinctrl.txt11
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index a9b47163bb5d..4976389e432d 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -714,6 +714,7 @@ static struct pinmux_ops foo_pmxops = {
.get_function_name = foo_get_fname,
.get_function_groups = foo_get_groups,
.set_mux = foo_set_mux,
+ .strict = true,
};
/* Pinmux operations are handled by some pin controller */
@@ -830,6 +831,11 @@ separate memory range only intended for GPIO driving, and the register
range dealing with pin config and pin multiplexing get placed into a
different memory range and a separate section of the data sheet.
+A flag "strict" in struct pinctrl_desc is available to check and deny
+simultaneous access to the same pin from GPIO and pin multiplexing
+consumers on hardware of this type. The pinctrl driver should set this flag
+accordingly.
+
(B)
pin config
@@ -850,6 +856,11 @@ possible that the GPIO, pin config and pin multiplex registers are placed into
the same memory range and the same section of the data sheet, although that
need not be the case.
+In some pin controllers, although the physical pins are designed in the same
+way as (B), the GPIO function still can't be enabled at the same time as the
+peripheral functions. So again the "strict" flag should be set, denying
+simultaneous activation by GPIO and other muxed in devices.
+
From a kernel point of view, however, these are different aspects of the
hardware and shall be put into different subsystems: