RE: [PATCH v4 2/4] mfd: omap: control: core system control driver
From: AnilKumar, Chimata <hidden>
Date: 2012-08-29 12:33:26
Also in:
linux-arm-kernel, linux-omap
Hi Konstantin, On Wed, Jul 25, 2012 at 16:35:16, Konstantin Baydarov wrote:
quoted hunk ↗ jump to hunk
This patch introduces a MFD core device driver for OMAP system control module. The control module allows software control of various static modes supported by the device. It is composed of two control submodules: general control module and device (padconfiguration) control module. Device driver is probed with postcore_initcall. Control module register CONTROL_STATUS that is needed by omap_type() is early mapped by postcore_initcall_sync. Signed-off-by: J Keerthy <j-keerthy@ti.com> Signed-off-by: Kishon Vijay Abraham I <redacted> Signed-off-by: Eduardo Valentin <redacted> Signed-off-by: Konstantin Baydarov <redacted> --- .../devicetree/bindings/mfd/omap_control.txt | 32 ++++ arch/arm/mach-omap2/Kconfig | 1 + arch/arm/plat-omap/Kconfig | 4 + drivers/mfd/Kconfig | 6 + drivers/mfd/Makefile | 1 + drivers/mfd/omap-control-core.c | 162 ++++++++++++++++++++ include/linux/mfd/omap_control.h | 35 +++++ 7 files changed, 241 insertions(+), 0 deletions(-) create mode 100644 Documentation/devicetree/bindings/mfd/omap_control.txt create mode 100644 drivers/mfd/omap-control-core.c create mode 100644 include/linux/mfd/omap_control.hdiff --git a/Documentation/devicetree/bindings/mfd/omap_control.txt b/Documentation/devicetree/bindings/mfd/omap_control.txt new file mode 100644 index 0000000..a9dca9e --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/omap_control.txt@@ -0,0 +1,32 @@ +* Texas Instrument OMAP System Control Module (SCM) bindings + +The control module allows software control of various static modes supported by +the device. The control module controls the settings of various device modules +through register configuration and internal signals. It also controls the pad +configuration, pin functional multiplexing, and the routing of internal signals +(such as PRCM signals or DMA requests) to output pins configured for hardware +observability. + +Required properties: +- compatible : Should be: + - "ti,omap3-control" for OMAP3 support + - "ti,omap4-control" for OMAP4 support + - "ti,omap5-control" for OMAP5 support + +OMAP specific properties: +- ti,hwmods: Name of the hwmod associated to the control module: + Should be "ctrl_module_core"; + +OMAP CONTROL_STATUS register: +reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */ + +Examples: +ctrl_module_core: ctrl_module_core@4A0022C4 { + compatible = "ti,omap4-control"; + #address-cells = <1>; + #size-cells = <1>; + /* ranges; */ + ti,hwmods = "ctrl_module_core"; + reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */ +}; +diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig index dd0fbf7..1235576 100644 --- a/arch/arm/mach-omap2/Kconfig +++ b/arch/arm/mach-omap2/Kconfig@@ -59,6 +59,7 @@ config ARCH_OMAP4 select ARM_ERRATA_720789 select ARCH_HAS_OPP select PM_RUNTIME if CPU_IDLE + select ARCH_HAS_CONTROL_MODULE select PM_OPP if PM select USB_ARCH_HAS_EHCI if USB_SUPPORT select ARM_CPU_SUSPEND if PMdiff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig index dd36eba..2b2c9d8 100644 --- a/arch/arm/plat-omap/Kconfig +++ b/arch/arm/plat-omap/Kconfig@@ -5,6 +5,10 @@ menu "TI OMAP Common Features" config ARCH_OMAP_OTG bool +config ARCH_HAS_CONTROL_MODULE + bool + select MFD_OMAP_CONTROL + choice prompt "OMAP System Type" default ARCH_OMAP2PLUSdiff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 92144ed..530ac60 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig@@ -823,6 +823,12 @@ config MFD_WL1273_CORE driver connects the radio-wl1273 V4L2 module and the wl1273 audio codec. +config MFD_OMAP_CONTROL + bool "Texas Instruments OMAP System control module" + depends on ARCH_HAS_CONTROL_MODULE + help + This is the core driver for system control module. + config MFD_OMAP_USB_HOST bool "Support OMAP USBHS core driver" depends on USB_EHCI_HCD_OMAP || USB_OHCI_HCD_OMAP3diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index 75f6ed6..b037443 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile@@ -107,6 +107,7 @@ obj-$(CONFIG_MFD_TPS6586X) += tps6586x.o obj-$(CONFIG_MFD_VX855) += vx855.o obj-$(CONFIG_MFD_WL1273_CORE) += wl1273-core.o obj-$(CONFIG_MFD_CS5535) += cs5535-mfd.o +obj-$(CONFIG_MFD_OMAP_CONTROL) += omap-control-core.o obj-$(CONFIG_MFD_OMAP_USB_HOST) += omap-usb-host.o obj-$(CONFIG_MFD_PM8921_CORE) += pm8921-core.o obj-$(CONFIG_MFD_PM8XXX_IRQ) += pm8xxx-irq.odiff --git a/drivers/mfd/omap-control-core.c b/drivers/mfd/omap-control-core.c new file mode 100644 index 0000000..cefbc5a --- /dev/null +++ b/drivers/mfd/omap-control-core.c@@ -0,0 +1,162 @@ +/* + * OMAP system control module driver file + * + * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/ + * Contacts: + * Based on original code written by: + * J Keerthy <j-keerthy@ti.com> + * Moiz Sonasath <m-sonasath@ti.com> + * MFD clean up and re-factoring: + * Eduardo Valentin <eduardo.valentin@ti.com> + * Konstantin Baydarov <kbaidarov@dev.rtsoft.ru> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + */ + +#include <linux/module.h> +#include <linux/export.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/of_platform.h> +#include <linux/of_address.h> +#include <linux/mfd/core.h> +#include <linux/mfd/omap_control.h> + +#include <linux/of.h> +#include <linux/of_address.h> + +void __iomem *omap_control_base; +unsigned long omap_control_phys_base; +size_t omap_control_mapsize; + +u32 omap_control_status_read(void) +{ + return __raw_readl(omap_control_base); +}
In AM335X, D_CAN IP uses single CONTROL module register to
initialize D_CAN ram (D_CAN_RAMINIT). In order to enable
D_CAN RAM we have to write to that register in sync with
clock enable/disable.
How can I use this driver to handle this usecase? Similar to
above API?
Currently this is handled using platform call back (example below)
In arch/arm/mach-omap2/devices.c:
static void d_can_hw_raminit(unsigned int instance, unsigned int enable)
{
u32 val;
/* Read the value */
val = readl(AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
if (enable) {
/* Set to "1" */
val &= ~AM33XX_DCAN_RAMINIT_START(instance);
val |= AM33XX_DCAN_RAMINIT_START(instance);
writel(val, AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
} else {
/* Set to "0" */
val &= ~AM33XX_DCAN_RAMINIT_START(instance);
writel(val, AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
}
}
In drivers/net/can/c_can/c_can.c:
void d_can_reset_ram(struct d_can_priv *d_can, unsigned int instance,
unsigned int enable)
{
if (d_can->ram_init)
d_can->ram_init(instance, enable);
}
Thanks
AnilKumar