From: Stephen Gallimore <stephen.gallimore@xxxxxx> This patch adds a reset controller platform driver for the STiH415 SoC. This initial version provides a compatible driver for the "st,stih415-powerdown" device, which registers a system configuration register based reset controller that controls the powerdown state of hardware such as the on-chip USB host controllers. Signed-off-by: Stephen Gallimore <stephen.gallimore@xxxxxx> --- .../devicetree/bindings/reset/st,sti-powerdown.txt | 47 ++++++++++++ arch/arm/boot/dts/stih415.dtsi | 6 ++ drivers/reset/sti/Kconfig | 4 + drivers/reset/sti/Makefile | 3 + drivers/reset/sti/reset-stih415.c | 77 ++++++++++++++++++++ .../dt-bindings/reset-controller/stih415-resets.h | 19 +++++ 6 files changed, 156 insertions(+) create mode 100644 Documentation/devicetree/bindings/reset/st,sti-powerdown.txt create mode 100644 drivers/reset/sti/reset-stih415.c create mode 100644 include/dt-bindings/reset-controller/stih415-resets.h diff --git a/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt b/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt new file mode 100644 index 0000000..5ab26b7 --- /dev/null +++ b/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt @@ -0,0 +1,47 @@ +STMicroelectronics STi family Sysconfig Peripheral Powerdown Reset Controller +============================================================================= + +This binding describes a reset controller device that is used to enable and +disable on-chip peripheral controllers such as USB and SATA, using +"powerdown" control bits found in the STi family SoC system configuration +registers. These have been grouped together into a single reset controller +device for convenience. + +The actual action taken when powerdown is asserted is hardware dependent. +However, when asserted it may not be possible to access the hardware's +registers and after an assert/deassert sequence the hardware's previous state +may no longer be valid. + +Please refer to reset.txt in this directory for common reset +controller binding usage. + +Required properties: +- compatible: Should be "st,<chip>-powerdown" + ex: "st,stih415-powerdown", "st,stih416-powerdown" +- #reset-cells: 1, see below + +example: + + powerdown: powerdown-controller { + #reset-cells = <1>; + compatible = "st,stih415-powerdown"; + }; + + +Specifying powerdown control of devices +======================================= + +Device nodes should specify the reset channel required in their "resets" +property, containing a phandle to the powerdown device node and an +index specifying which channel to use, as described in reset.txt + +example: + + usb1: usb@fe200000 { + resets = <&powerdown STIH41X_USB1_POWERDOWN>; + }; + +Macro definitions for the supported reset channels can be found in: + +include/dt-bindings/reset-controller/stih415-resets.h +include/dt-bindings/reset-controller/stih416-resets.h diff --git a/arch/arm/boot/dts/stih415.dtsi b/arch/arm/boot/dts/stih415.dtsi index d9c7dd1..19e29f4 100644 --- a/arch/arm/boot/dts/stih415.dtsi +++ b/arch/arm/boot/dts/stih415.dtsi @@ -10,6 +10,7 @@ #include "stih415-clock.dtsi" #include "stih415-pinctrl.dtsi" #include <dt-bindings/interrupt-controller/arm-gic.h> +#include <dt-bindings/reset-controller/stih415-resets.h> / { L2: cache-controller { @@ -28,6 +29,11 @@ ranges; compatible = "simple-bus"; + powerdown: powerdown-controller { + #reset-cells = <1>; + compatible = "st,stih415-powerdown"; + }; + syscfg_sbc: sbc-syscfg@fe600000{ compatible = "st,stih415-sbc-syscfg", "syscon"; reg = <0xfe600000 0xb4>; diff --git a/drivers/reset/sti/Kconfig b/drivers/reset/sti/Kconfig index ba13796..ef6654a 100644 --- a/drivers/reset/sti/Kconfig +++ b/drivers/reset/sti/Kconfig @@ -4,4 +4,8 @@ config STI_RESET_SYSCFG bool select RESET_CONTROLLER +config STIH415_RESET + bool + select STI_RESET_SYSCFG + endif diff --git a/drivers/reset/sti/Makefile b/drivers/reset/sti/Makefile index c4a51d9..fce4433 100644 --- a/drivers/reset/sti/Makefile +++ b/drivers/reset/sti/Makefile @@ -1 +1,4 @@ obj-$(CONFIG_STI_RESET_SYSCFG) += reset-syscfg.o + +# SoC specific reset devices +obj-$(CONFIG_STIH415_RESET) += reset-stih415.o diff --git a/drivers/reset/sti/reset-stih415.c b/drivers/reset/sti/reset-stih415.c new file mode 100644 index 0000000..56c2146 --- /dev/null +++ b/drivers/reset/sti/reset-stih415.c @@ -0,0 +1,77 @@ +/* + * Copyright (C) 2013 STMicroelectronics (R&D) Limited + * Author: Stephen Gallimore <stephen.gallimore@xxxxxx> + * Author: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +#include <dt-bindings/reset-controller/stih415-resets.h> + +#include "reset-syscfg.h" + +/* + * STiH415 Peripheral powerdown definitions. + */ +static const char stih415_front[] = "st,stih415-front-syscfg"; +static const char stih415_rear[] = "st,stih415-rear-syscfg"; +static const char stih415_sbc[] = "st,stih415-sbc-syscfg"; +static const char stih415_lpm[] = "st,stih415-lpm-syscfg"; + +#define STIH415_PDN_FRONT(_bit) \ + _SYSCFG_RST_CH(stih415_front, SYSCFG_114, _bit, SYSSTAT_187, _bit) + +#define STIH415_PDN_REAR(_cntl, _stat) \ + _SYSCFG_RST_CH(stih415_rear, SYSCFG_336, _cntl, SYSSTAT_384, _stat) + +#define SYSCFG_114 0x38 /* Powerdown request EMI/NAND/Keyscan */ +#define SYSSTAT_187 0x15c /* Powerdown status EMI/NAND/Keyscan */ + +#define SYSCFG_336 0x90 /* Powerdown request USB/SATA/PCIe */ +#define SYSSTAT_384 0x150 /* Powerdown status USB/SATA/PCIe */ + +static const struct syscfg_reset_channel_data stih415_powerdowns[] = { + [STIH415_EMISS_POWERDOWN] = STIH415_PDN_FRONT(0), + [STIH415_NAND_POWERDOWN] = STIH415_PDN_FRONT(1), + [STIH415_KEYSCAN_POWERDOWN] = STIH415_PDN_FRONT(2), + [STIH415_USB0_POWERDOWN] = STIH415_PDN_REAR(0, 0), + [STIH415_USB1_POWERDOWN] = STIH415_PDN_REAR(1, 1), + [STIH415_USB2_POWERDOWN] = STIH415_PDN_REAR(2, 2), + [STIH415_SATA0_POWERDOWN] = STIH415_PDN_REAR(3, 3), + [STIH415_SATA1_POWERDOWN] = STIH415_PDN_REAR(4, 4), + [STIH415_PCIE_POWERDOWN] = STIH415_PDN_REAR(5, 8), +}; + +static struct syscfg_reset_controller_data stih415_powerdown_controller = { + .wait_for_ack = true, + .nr_channels = ARRAY_SIZE(stih415_powerdowns), + .channels = stih415_powerdowns, +}; + +static struct of_device_id stih415_reset_match[] = { + { .compatible = "st,stih415-powerdown", + .data = &stih415_powerdown_controller, }, + {}, +}; + +static struct platform_driver stih415_reset_driver = { + .probe = syscfg_reset_probe, + .driver = { + .name = "reset-stih415", + .owner = THIS_MODULE, + .of_match_table = stih415_reset_match, + }, +}; + +static int __init stih415_reset_init(void) +{ + return platform_driver_register(&stih415_reset_driver); +} +arch_initcall(stih415_reset_init); diff --git a/include/dt-bindings/reset-controller/stih415-resets.h b/include/dt-bindings/reset-controller/stih415-resets.h new file mode 100644 index 0000000..2d54e68 --- /dev/null +++ b/include/dt-bindings/reset-controller/stih415-resets.h @@ -0,0 +1,19 @@ +/* + * This header provides constants for the reset controller + * based peripheral powerdown requests on the STMicroelectronics + * STiH415 SoC. + */ +#ifndef _DT_BINDINGS_RESET_CONTROLLER_STIH415 +#define _DT_BINDINGS_RESET_CONTROLLER_STIH415 + +#define STIH415_EMISS_POWERDOWN 0 +#define STIH415_NAND_POWERDOWN 1 +#define STIH415_KEYSCAN_POWERDOWN 2 +#define STIH415_USB0_POWERDOWN 3 +#define STIH415_USB1_POWERDOWN 4 +#define STIH415_USB2_POWERDOWN 5 +#define STIH415_SATA0_POWERDOWN 6 +#define STIH415_SATA1_POWERDOWN 7 +#define STIH415_PCIE_POWERDOWN 8 + +#endif /* _DT_BINDINGS_RESET_CONTROLLER_STIH415 */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html