diff options
author | Daniel Lezcano <daniel.lezcano@linaro.org> | 2019-02-19 13:06:46 +0300 |
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committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2019-02-23 14:13:45 +0300 |
commit | 371eec9b822b25c0fd8523487a78050ad813db7e (patch) | |
tree | 315353fd29d3db88708359977691b6d01efdcd42 /drivers/clocksource/cs5535-clockevt.c | |
parent | eb36f29347fd78ba00485376a9fe11a3d02963c1 (diff) | |
download | linux-371eec9b822b25c0fd8523487a78050ad813db7e.tar.xz |
clocksource/drivers/timer-cs5535: Rename the file for consistency
For the sake of consistency, let's rename the file to a name similar
to other file names in this directory.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Diffstat (limited to 'drivers/clocksource/cs5535-clockevt.c')
-rw-r--r-- | drivers/clocksource/cs5535-clockevt.c | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/drivers/clocksource/cs5535-clockevt.c b/drivers/clocksource/cs5535-clockevt.c deleted file mode 100644 index 1de8cac99a0e..000000000000 --- a/drivers/clocksource/cs5535-clockevt.c +++ /dev/null @@ -1,196 +0,0 @@ -/* - * Clock event driver for the CS5535/CS5536 - * - * Copyright (C) 2006, Advanced Micro Devices, Inc. - * Copyright (C) 2007 Andres Salomon <dilinger@debian.org> - * Copyright (C) 2009 Andres Salomon <dilinger@collabora.co.uk> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public License - * as published by the Free Software Foundation. - * - * The MFGPTs are documented in AMD Geode CS5536 Companion Device Data Book. - */ - -#include <linux/kernel.h> -#include <linux/irq.h> -#include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/cs5535.h> -#include <linux/clockchips.h> - -#define DRV_NAME "cs5535-clockevt" - -static int timer_irq; -module_param_hw_named(irq, timer_irq, int, irq, 0644); -MODULE_PARM_DESC(irq, "Which IRQ to use for the clock source MFGPT ticks."); - -/* - * We are using the 32.768kHz input clock - it's the only one that has the - * ranges we find desirable. The following table lists the suitable - * divisors and the associated Hz, minimum interval and the maximum interval: - * - * Divisor Hz Min Delta (s) Max Delta (s) - * 1 32768 .00048828125 2.000 - * 2 16384 .0009765625 4.000 - * 4 8192 .001953125 8.000 - * 8 4096 .00390625 16.000 - * 16 2048 .0078125 32.000 - * 32 1024 .015625 64.000 - * 64 512 .03125 128.000 - * 128 256 .0625 256.000 - * 256 128 .125 512.000 - */ - -static struct cs5535_mfgpt_timer *cs5535_event_clock; - -/* Selected from the table above */ - -#define MFGPT_DIVISOR 16 -#define MFGPT_SCALE 4 /* divisor = 2^(scale) */ -#define MFGPT_HZ (32768 / MFGPT_DIVISOR) -#define MFGPT_PERIODIC (MFGPT_HZ / HZ) - -/* - * The MFGPT timers on the CS5536 provide us with suitable timers to use - * as clock event sources - not as good as a HPET or APIC, but certainly - * better than the PIT. This isn't a general purpose MFGPT driver, but - * a simplified one designed specifically to act as a clock event source. - * For full details about the MFGPT, please consult the CS5536 data sheet. - */ - -static void disable_timer(struct cs5535_mfgpt_timer *timer) -{ - /* avoid races by clearing CMP1 and CMP2 unconditionally */ - cs5535_mfgpt_write(timer, MFGPT_REG_SETUP, - (uint16_t) ~MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP1 | - MFGPT_SETUP_CMP2); -} - -static void start_timer(struct cs5535_mfgpt_timer *timer, uint16_t delta) -{ - cs5535_mfgpt_write(timer, MFGPT_REG_CMP2, delta); - cs5535_mfgpt_write(timer, MFGPT_REG_COUNTER, 0); - - cs5535_mfgpt_write(timer, MFGPT_REG_SETUP, - MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2); -} - -static int mfgpt_shutdown(struct clock_event_device *evt) -{ - disable_timer(cs5535_event_clock); - return 0; -} - -static int mfgpt_set_periodic(struct clock_event_device *evt) -{ - disable_timer(cs5535_event_clock); - start_timer(cs5535_event_clock, MFGPT_PERIODIC); - return 0; -} - -static int mfgpt_next_event(unsigned long delta, struct clock_event_device *evt) -{ - start_timer(cs5535_event_clock, delta); - return 0; -} - -static struct clock_event_device cs5535_clockevent = { - .name = DRV_NAME, - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .set_state_shutdown = mfgpt_shutdown, - .set_state_periodic = mfgpt_set_periodic, - .set_state_oneshot = mfgpt_shutdown, - .tick_resume = mfgpt_shutdown, - .set_next_event = mfgpt_next_event, - .rating = 250, -}; - -static irqreturn_t mfgpt_tick(int irq, void *dev_id) -{ - uint16_t val = cs5535_mfgpt_read(cs5535_event_clock, MFGPT_REG_SETUP); - - /* See if the interrupt was for us */ - if (!(val & (MFGPT_SETUP_SETUP | MFGPT_SETUP_CMP2 | MFGPT_SETUP_CMP1))) - return IRQ_NONE; - - /* Turn off the clock (and clear the event) */ - disable_timer(cs5535_event_clock); - - if (clockevent_state_detached(&cs5535_clockevent) || - clockevent_state_shutdown(&cs5535_clockevent)) - return IRQ_HANDLED; - - /* Clear the counter */ - cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_COUNTER, 0); - - /* Restart the clock in periodic mode */ - - if (clockevent_state_periodic(&cs5535_clockevent)) - cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_SETUP, - MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2); - - cs5535_clockevent.event_handler(&cs5535_clockevent); - return IRQ_HANDLED; -} - -static struct irqaction mfgptirq = { - .handler = mfgpt_tick, - .flags = IRQF_NOBALANCING | IRQF_TIMER | IRQF_SHARED, - .name = DRV_NAME, -}; - -static int __init cs5535_mfgpt_init(void) -{ - struct cs5535_mfgpt_timer *timer; - int ret; - uint16_t val; - - timer = cs5535_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING); - if (!timer) { - printk(KERN_ERR DRV_NAME ": Could not allocate MFGPT timer\n"); - return -ENODEV; - } - cs5535_event_clock = timer; - - /* Set up the IRQ on the MFGPT side */ - if (cs5535_mfgpt_setup_irq(timer, MFGPT_CMP2, &timer_irq)) { - printk(KERN_ERR DRV_NAME ": Could not set up IRQ %d\n", - timer_irq); - goto err_timer; - } - - /* And register it with the kernel */ - ret = setup_irq(timer_irq, &mfgptirq); - if (ret) { - printk(KERN_ERR DRV_NAME ": Unable to set up the interrupt.\n"); - goto err_irq; - } - - /* Set the clock scale and enable the event mode for CMP2 */ - val = MFGPT_SCALE | (3 << 8); - - cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_SETUP, val); - - /* Set up the clock event */ - printk(KERN_INFO DRV_NAME - ": Registering MFGPT timer as a clock event, using IRQ %d\n", - timer_irq); - clockevents_config_and_register(&cs5535_clockevent, MFGPT_HZ, - 0xF, 0xFFFE); - - return 0; - -err_irq: - cs5535_mfgpt_release_irq(cs5535_event_clock, MFGPT_CMP2, &timer_irq); -err_timer: - cs5535_mfgpt_free_timer(cs5535_event_clock); - printk(KERN_ERR DRV_NAME ": Unable to set up the MFGPT clock source\n"); - return -EIO; -} - -module_init(cs5535_mfgpt_init); - -MODULE_AUTHOR("Andres Salomon <dilinger@queued.net>"); -MODULE_DESCRIPTION("CS5535/CS5536 MFGPT clock event driver"); -MODULE_LICENSE("GPL"); |