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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-04 11:35:03 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-04 11:35:03 -0700 |
commit | 8bd8fd0a29bfd5ad8e1976edd8c4c40cdb39aa4f (patch) | |
tree | 1d7b2e30083194cc4223d9b150583fc2924bd032 /drivers/clocksource | |
parent | 352712274507645b6f82b8763977ad87321919a3 (diff) | |
parent | 5a688c455066c21c133bc8ffa7b11f8c66b7fe0b (diff) | |
download | linux-8bd8fd0a29bfd5ad8e1976edd8c4c40cdb39aa4f.tar.bz2 |
Merge tag 'mfd-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones:
"New Device Support:
- New Clocksource driver from ST
- New MFD/ACPI/DMA drivers for Intel's Sunrisepoint PCH based platforms
- Add support for Arizona WM8998 and WM1814
- Add support for Dialog Semi DA9062 and DA9063
- Add support for Kontron COMe-bBL6 and COMe-cBW6
- Add support for X-Powers AXP152
- Add support for Atmel, many
- Add support for STMPE, many
- Add support for USB in X-Powers AXP22X
Core Frameworks:
- New Base API to traverse devices and their children in reverse order
Bug Fixes:
- Fix race between runtime-suspend and IRQs
- Obtain platform data form more reliable source
Fix-ups:
- Constifying things
- Variable signage changes
- Kconfig depends|selects changes
- Make use of BIT() macro
- Do not supply .owner attribute in *_driver structures
- MAINTAINERS entries
- Stop using set_irq_flags()
- Start using irq_set_chained_handler_and_data()
- Export DT device ID structures"
* tag 'mfd-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (69 commits)
mfd: jz4740-adc: Init mask cache in generic IRQ chip
mfd: cros_ec: spi: Add OF match table
mfd: stmpe: Add OF match table
mfd: max77686: Split out regulator part from the DT binding
mfd: Add DT binding for Maxim MAX77802 IC
mfd: max77686: Use a generic name for the PMIC node in the example
mfd: max77686: Don't suggest in binding to use a deprecated property
mfd: Add MFD_CROS_EC dependencies
mfd: cros_ec: Remove CROS_EC_PROTO dependency for SPI and I2C drivers
mfd: axp20x: Add a cell for the usb power_supply part of the axp20x PMICs
mfd: axp20x: Add missing registers, and mark more registers volatile
mfd: arizona: Fixup some formatting/white space errors
mfd: wm8994: Fix NULL pointer exception on missing pdata
of: Add vendor prefix for Nuvoton
mfd: mt6397: Implement wake handler and suspend/resume to handle wake up event
mfd: atmel-hlcdc: Add support for new SoCs
mfd: Export OF module alias information in missing drivers
mfd: stw481x: Export I2C module alias information
mfd: da9062: Support for the DA9063 OnKey in the DA9062 core
mfd: max899x: Avoid redundant irq_data lookup
...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r-- | drivers/clocksource/Kconfig | 8 | ||||
-rw-r--r-- | drivers/clocksource/Makefile | 1 | ||||
-rw-r--r-- | drivers/clocksource/clksrc_st_lpc.c | 131 |
3 files changed, 140 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 552c9b134cc5..a7726db13abb 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -297,4 +297,12 @@ config CLKSRC_IMX_GPT depends on ARM && CLKDEV_LOOKUP select CLKSRC_MMIO +config CLKSRC_ST_LPC + bool + depends on ARCH_STI + select CLKSRC_OF if OF + help + Enable this option to use the Low Power controller timer + as clocksource. + endmenu diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 066337e24737..5c00863c3e33 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -61,3 +61,4 @@ obj-$(CONFIG_ASM9260_TIMER) += asm9260_timer.o obj-$(CONFIG_H8300) += h8300_timer8.o obj-$(CONFIG_H8300_TMR16) += h8300_timer16.o obj-$(CONFIG_H8300_TPU) += h8300_tpu.o +obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o diff --git a/drivers/clocksource/clksrc_st_lpc.c b/drivers/clocksource/clksrc_st_lpc.c new file mode 100644 index 000000000000..65ec4674416d --- /dev/null +++ b/drivers/clocksource/clksrc_st_lpc.c @@ -0,0 +1,131 @@ +/* + * Clocksource using the Low Power Timer found in the Low Power Controller (LPC) + * + * Copyright (C) 2015 STMicroelectronics – All Rights Reserved + * + * Author(s): Francesco Virlinzi <francesco.virlinzi@st.com> + * Ajit Pal Singh <ajitpal.singh@st.com> + * + * 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/clk.h> +#include <linux/clocksource.h> +#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/sched_clock.h> +#include <linux/slab.h> + +#include <dt-bindings/mfd/st-lpc.h> + +/* Low Power Timer */ +#define LPC_LPT_LSB_OFF 0x400 +#define LPC_LPT_MSB_OFF 0x404 +#define LPC_LPT_START_OFF 0x408 + +static struct st_clksrc_ddata { + struct clk *clk; + void __iomem *base; +} ddata; + +static void __init st_clksrc_reset(void) +{ + writel_relaxed(0, ddata.base + LPC_LPT_START_OFF); + writel_relaxed(0, ddata.base + LPC_LPT_MSB_OFF); + writel_relaxed(0, ddata.base + LPC_LPT_LSB_OFF); + writel_relaxed(1, ddata.base + LPC_LPT_START_OFF); +} + +static u64 notrace st_clksrc_sched_clock_read(void) +{ + return (u64)readl_relaxed(ddata.base + LPC_LPT_LSB_OFF); +} + +static int __init st_clksrc_init(void) +{ + unsigned long rate; + int ret; + + st_clksrc_reset(); + + rate = clk_get_rate(ddata.clk); + + sched_clock_register(st_clksrc_sched_clock_read, 32, rate); + + ret = clocksource_mmio_init(ddata.base + LPC_LPT_LSB_OFF, + "clksrc-st-lpc", rate, 300, 32, + clocksource_mmio_readl_up); + if (ret) { + pr_err("clksrc-st-lpc: Failed to register clocksource\n"); + return ret; + } + + return 0; +} + +static int __init st_clksrc_setup_clk(struct device_node *np) +{ + struct clk *clk; + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + pr_err("clksrc-st-lpc: Failed to get LPC clock\n"); + return PTR_ERR(clk); + } + + if (clk_prepare_enable(clk)) { + pr_err("clksrc-st-lpc: Failed to enable LPC clock\n"); + return -EINVAL; + } + + if (!clk_get_rate(clk)) { + pr_err("clksrc-st-lpc: Failed to get LPC clock rate\n"); + clk_disable_unprepare(clk); + return -EINVAL; + } + + ddata.clk = clk; + + return 0; +} + +static void __init st_clksrc_of_register(struct device_node *np) +{ + int ret; + uint32_t mode; + + ret = of_property_read_u32(np, "st,lpc-mode", &mode); + if (ret) { + pr_err("clksrc-st-lpc: An LPC mode must be provided\n"); + return; + } + + /* LPC can either run as a Clocksource or in RTC or WDT mode */ + if (mode != ST_LPC_MODE_CLKSRC) + return; + + ddata.base = of_iomap(np, 0); + if (!ddata.base) { + pr_err("clksrc-st-lpc: Unable to map iomem\n"); + return; + } + + if (st_clksrc_setup_clk(np)) { + iounmap(ddata.base); + return; + } + + if (st_clksrc_init()) { + clk_disable_unprepare(ddata.clk); + clk_put(ddata.clk); + iounmap(ddata.base); + return; + } + + pr_info("clksrc-st-lpc: clocksource initialised - running @ %luHz\n", + clk_get_rate(ddata.clk)); +} +CLOCKSOURCE_OF_DECLARE(ddata, "st,stih407-lpc", st_clksrc_of_register); |