forked from Minki/linux
1b3f828760
Pull clocksource/clockevent updates from Daniel Lezcano: * Axel Lin removed an unused structure defining the ids for the bcm kona driver. * Ezequiel Garcia enabled the timer divider only when the 25MHz timer is not used for the armada 370 XP. * Jingoo Han removed a pointless platform data initialization for the sh_mtu and sh_mtu2. * Laurent Pinchart added the clk_prepare/clk_unprepare for sh_cmt. * Linus Walleij added a useful warning in clk_of when no clocks are found while the old behavior was to silently hang at boot time. * Maxime Ripard added the high speed timer drivers for the Allwinner SoCs (A10, A13, A20). He increased the rating, shared the irq across all available cpus and fixed the clockevent's irq initialization for the sun4i. * Michael Opdenacker removed the usage of the IRQF_DISABLED for the all the timers driver located in drivers/clocksource. * Stephen Boyd switched to sched_clock_register for the arm_global_timer, cadence_ttc, sun4i and orion timers. Conflicts: drivers/clocksource/clksrc-of.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
570 lines
12 KiB
C
570 lines
12 KiB
C
/*
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* SuperH Timer Support - TMU
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*
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* Copyright (C) 2009 Magnus Damm
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/init.h>
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#include <linux/platform_device.h>
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#include <linux/spinlock.h>
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#include <linux/interrupt.h>
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#include <linux/ioport.h>
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#include <linux/delay.h>
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#include <linux/io.h>
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#include <linux/clk.h>
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#include <linux/irq.h>
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#include <linux/err.h>
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#include <linux/clocksource.h>
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#include <linux/clockchips.h>
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#include <linux/sh_timer.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/pm_domain.h>
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#include <linux/pm_runtime.h>
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struct sh_tmu_priv {
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void __iomem *mapbase;
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struct clk *clk;
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struct irqaction irqaction;
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struct platform_device *pdev;
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unsigned long rate;
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unsigned long periodic;
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struct clock_event_device ced;
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struct clocksource cs;
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bool cs_enabled;
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unsigned int enable_count;
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};
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static DEFINE_RAW_SPINLOCK(sh_tmu_lock);
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#define TSTR -1 /* shared register */
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#define TCOR 0 /* channel register */
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#define TCNT 1 /* channel register */
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#define TCR 2 /* channel register */
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static inline unsigned long sh_tmu_read(struct sh_tmu_priv *p, int reg_nr)
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{
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struct sh_timer_config *cfg = p->pdev->dev.platform_data;
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void __iomem *base = p->mapbase;
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unsigned long offs;
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if (reg_nr == TSTR)
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return ioread8(base - cfg->channel_offset);
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offs = reg_nr << 2;
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if (reg_nr == TCR)
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return ioread16(base + offs);
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else
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return ioread32(base + offs);
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}
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static inline void sh_tmu_write(struct sh_tmu_priv *p, int reg_nr,
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unsigned long value)
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{
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struct sh_timer_config *cfg = p->pdev->dev.platform_data;
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void __iomem *base = p->mapbase;
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unsigned long offs;
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if (reg_nr == TSTR) {
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iowrite8(value, base - cfg->channel_offset);
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return;
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}
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offs = reg_nr << 2;
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if (reg_nr == TCR)
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iowrite16(value, base + offs);
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else
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iowrite32(value, base + offs);
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}
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static void sh_tmu_start_stop_ch(struct sh_tmu_priv *p, int start)
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{
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struct sh_timer_config *cfg = p->pdev->dev.platform_data;
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unsigned long flags, value;
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/* start stop register shared by multiple timer channels */
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raw_spin_lock_irqsave(&sh_tmu_lock, flags);
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value = sh_tmu_read(p, TSTR);
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if (start)
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value |= 1 << cfg->timer_bit;
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else
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value &= ~(1 << cfg->timer_bit);
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sh_tmu_write(p, TSTR, value);
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raw_spin_unlock_irqrestore(&sh_tmu_lock, flags);
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}
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static int __sh_tmu_enable(struct sh_tmu_priv *p)
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{
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int ret;
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/* enable clock */
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ret = clk_enable(p->clk);
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if (ret) {
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dev_err(&p->pdev->dev, "cannot enable clock\n");
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return ret;
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}
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/* make sure channel is disabled */
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sh_tmu_start_stop_ch(p, 0);
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/* maximum timeout */
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sh_tmu_write(p, TCOR, 0xffffffff);
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sh_tmu_write(p, TCNT, 0xffffffff);
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/* configure channel to parent clock / 4, irq off */
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p->rate = clk_get_rate(p->clk) / 4;
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sh_tmu_write(p, TCR, 0x0000);
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/* enable channel */
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sh_tmu_start_stop_ch(p, 1);
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return 0;
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}
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static int sh_tmu_enable(struct sh_tmu_priv *p)
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{
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if (p->enable_count++ > 0)
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return 0;
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pm_runtime_get_sync(&p->pdev->dev);
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dev_pm_syscore_device(&p->pdev->dev, true);
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return __sh_tmu_enable(p);
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}
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static void __sh_tmu_disable(struct sh_tmu_priv *p)
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{
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/* disable channel */
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sh_tmu_start_stop_ch(p, 0);
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/* disable interrupts in TMU block */
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sh_tmu_write(p, TCR, 0x0000);
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/* stop clock */
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clk_disable(p->clk);
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}
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static void sh_tmu_disable(struct sh_tmu_priv *p)
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{
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if (WARN_ON(p->enable_count == 0))
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return;
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if (--p->enable_count > 0)
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return;
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__sh_tmu_disable(p);
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dev_pm_syscore_device(&p->pdev->dev, false);
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pm_runtime_put(&p->pdev->dev);
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}
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static void sh_tmu_set_next(struct sh_tmu_priv *p, unsigned long delta,
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int periodic)
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{
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/* stop timer */
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sh_tmu_start_stop_ch(p, 0);
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/* acknowledge interrupt */
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sh_tmu_read(p, TCR);
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/* enable interrupt */
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sh_tmu_write(p, TCR, 0x0020);
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/* reload delta value in case of periodic timer */
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if (periodic)
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sh_tmu_write(p, TCOR, delta);
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else
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sh_tmu_write(p, TCOR, 0xffffffff);
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sh_tmu_write(p, TCNT, delta);
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/* start timer */
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sh_tmu_start_stop_ch(p, 1);
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}
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static irqreturn_t sh_tmu_interrupt(int irq, void *dev_id)
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{
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struct sh_tmu_priv *p = dev_id;
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/* disable or acknowledge interrupt */
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if (p->ced.mode == CLOCK_EVT_MODE_ONESHOT)
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sh_tmu_write(p, TCR, 0x0000);
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else
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sh_tmu_write(p, TCR, 0x0020);
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/* notify clockevent layer */
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p->ced.event_handler(&p->ced);
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return IRQ_HANDLED;
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}
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static struct sh_tmu_priv *cs_to_sh_tmu(struct clocksource *cs)
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{
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return container_of(cs, struct sh_tmu_priv, cs);
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}
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static cycle_t sh_tmu_clocksource_read(struct clocksource *cs)
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{
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struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
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return sh_tmu_read(p, TCNT) ^ 0xffffffff;
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}
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static int sh_tmu_clocksource_enable(struct clocksource *cs)
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{
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struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
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int ret;
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if (WARN_ON(p->cs_enabled))
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return 0;
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ret = sh_tmu_enable(p);
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if (!ret) {
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__clocksource_updatefreq_hz(cs, p->rate);
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p->cs_enabled = true;
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}
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return ret;
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}
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static void sh_tmu_clocksource_disable(struct clocksource *cs)
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{
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struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
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if (WARN_ON(!p->cs_enabled))
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return;
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sh_tmu_disable(p);
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p->cs_enabled = false;
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}
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static void sh_tmu_clocksource_suspend(struct clocksource *cs)
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{
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struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
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if (!p->cs_enabled)
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return;
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if (--p->enable_count == 0) {
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__sh_tmu_disable(p);
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pm_genpd_syscore_poweroff(&p->pdev->dev);
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}
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}
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static void sh_tmu_clocksource_resume(struct clocksource *cs)
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{
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struct sh_tmu_priv *p = cs_to_sh_tmu(cs);
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if (!p->cs_enabled)
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return;
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if (p->enable_count++ == 0) {
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pm_genpd_syscore_poweron(&p->pdev->dev);
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__sh_tmu_enable(p);
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}
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}
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static int sh_tmu_register_clocksource(struct sh_tmu_priv *p,
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char *name, unsigned long rating)
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{
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struct clocksource *cs = &p->cs;
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cs->name = name;
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cs->rating = rating;
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cs->read = sh_tmu_clocksource_read;
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cs->enable = sh_tmu_clocksource_enable;
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cs->disable = sh_tmu_clocksource_disable;
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cs->suspend = sh_tmu_clocksource_suspend;
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cs->resume = sh_tmu_clocksource_resume;
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cs->mask = CLOCKSOURCE_MASK(32);
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cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
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dev_info(&p->pdev->dev, "used as clock source\n");
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/* Register with dummy 1 Hz value, gets updated in ->enable() */
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clocksource_register_hz(cs, 1);
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return 0;
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}
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static struct sh_tmu_priv *ced_to_sh_tmu(struct clock_event_device *ced)
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{
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return container_of(ced, struct sh_tmu_priv, ced);
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}
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static void sh_tmu_clock_event_start(struct sh_tmu_priv *p, int periodic)
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{
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struct clock_event_device *ced = &p->ced;
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sh_tmu_enable(p);
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clockevents_config(ced, p->rate);
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if (periodic) {
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p->periodic = (p->rate + HZ/2) / HZ;
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sh_tmu_set_next(p, p->periodic, 1);
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}
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}
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static void sh_tmu_clock_event_mode(enum clock_event_mode mode,
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struct clock_event_device *ced)
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{
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struct sh_tmu_priv *p = ced_to_sh_tmu(ced);
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int disabled = 0;
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/* deal with old setting first */
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switch (ced->mode) {
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case CLOCK_EVT_MODE_PERIODIC:
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case CLOCK_EVT_MODE_ONESHOT:
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sh_tmu_disable(p);
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disabled = 1;
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break;
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default:
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break;
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}
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switch (mode) {
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case CLOCK_EVT_MODE_PERIODIC:
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dev_info(&p->pdev->dev, "used for periodic clock events\n");
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sh_tmu_clock_event_start(p, 1);
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break;
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case CLOCK_EVT_MODE_ONESHOT:
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dev_info(&p->pdev->dev, "used for oneshot clock events\n");
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sh_tmu_clock_event_start(p, 0);
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break;
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case CLOCK_EVT_MODE_UNUSED:
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if (!disabled)
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sh_tmu_disable(p);
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break;
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case CLOCK_EVT_MODE_SHUTDOWN:
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default:
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break;
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}
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}
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static int sh_tmu_clock_event_next(unsigned long delta,
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struct clock_event_device *ced)
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{
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struct sh_tmu_priv *p = ced_to_sh_tmu(ced);
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BUG_ON(ced->mode != CLOCK_EVT_MODE_ONESHOT);
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/* program new delta value */
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sh_tmu_set_next(p, delta, 0);
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return 0;
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}
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static void sh_tmu_clock_event_suspend(struct clock_event_device *ced)
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{
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pm_genpd_syscore_poweroff(&ced_to_sh_tmu(ced)->pdev->dev);
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}
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static void sh_tmu_clock_event_resume(struct clock_event_device *ced)
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{
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pm_genpd_syscore_poweron(&ced_to_sh_tmu(ced)->pdev->dev);
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}
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static void sh_tmu_register_clockevent(struct sh_tmu_priv *p,
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char *name, unsigned long rating)
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{
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struct clock_event_device *ced = &p->ced;
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int ret;
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memset(ced, 0, sizeof(*ced));
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ced->name = name;
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ced->features = CLOCK_EVT_FEAT_PERIODIC;
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ced->features |= CLOCK_EVT_FEAT_ONESHOT;
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ced->rating = rating;
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ced->cpumask = cpumask_of(0);
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ced->set_next_event = sh_tmu_clock_event_next;
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ced->set_mode = sh_tmu_clock_event_mode;
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ced->suspend = sh_tmu_clock_event_suspend;
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ced->resume = sh_tmu_clock_event_resume;
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dev_info(&p->pdev->dev, "used for clock events\n");
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clockevents_config_and_register(ced, 1, 0x300, 0xffffffff);
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ret = setup_irq(p->irqaction.irq, &p->irqaction);
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if (ret) {
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dev_err(&p->pdev->dev, "failed to request irq %d\n",
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p->irqaction.irq);
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return;
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}
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}
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static int sh_tmu_register(struct sh_tmu_priv *p, char *name,
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unsigned long clockevent_rating,
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unsigned long clocksource_rating)
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{
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if (clockevent_rating)
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sh_tmu_register_clockevent(p, name, clockevent_rating);
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else if (clocksource_rating)
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sh_tmu_register_clocksource(p, name, clocksource_rating);
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return 0;
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}
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static int sh_tmu_setup(struct sh_tmu_priv *p, struct platform_device *pdev)
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{
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struct sh_timer_config *cfg = pdev->dev.platform_data;
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struct resource *res;
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int irq, ret;
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ret = -ENXIO;
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memset(p, 0, sizeof(*p));
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p->pdev = pdev;
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if (!cfg) {
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dev_err(&p->pdev->dev, "missing platform data\n");
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goto err0;
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}
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platform_set_drvdata(pdev, p);
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res = platform_get_resource(p->pdev, IORESOURCE_MEM, 0);
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if (!res) {
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dev_err(&p->pdev->dev, "failed to get I/O memory\n");
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goto err0;
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}
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irq = platform_get_irq(p->pdev, 0);
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if (irq < 0) {
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dev_err(&p->pdev->dev, "failed to get irq\n");
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goto err0;
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}
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/* map memory, let mapbase point to our channel */
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p->mapbase = ioremap_nocache(res->start, resource_size(res));
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if (p->mapbase == NULL) {
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dev_err(&p->pdev->dev, "failed to remap I/O memory\n");
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goto err0;
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}
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/* setup data for setup_irq() (too early for request_irq()) */
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p->irqaction.name = dev_name(&p->pdev->dev);
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p->irqaction.handler = sh_tmu_interrupt;
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p->irqaction.dev_id = p;
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p->irqaction.irq = irq;
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p->irqaction.flags = IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING;
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/* get hold of clock */
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p->clk = clk_get(&p->pdev->dev, "tmu_fck");
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if (IS_ERR(p->clk)) {
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dev_err(&p->pdev->dev, "cannot get clock\n");
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ret = PTR_ERR(p->clk);
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goto err1;
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}
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ret = clk_prepare(p->clk);
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if (ret < 0)
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goto err2;
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p->cs_enabled = false;
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p->enable_count = 0;
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ret = sh_tmu_register(p, (char *)dev_name(&p->pdev->dev),
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cfg->clockevent_rating,
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cfg->clocksource_rating);
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if (ret < 0)
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goto err3;
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return 0;
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err3:
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clk_unprepare(p->clk);
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err2:
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clk_put(p->clk);
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err1:
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iounmap(p->mapbase);
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err0:
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return ret;
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}
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static int sh_tmu_probe(struct platform_device *pdev)
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{
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struct sh_tmu_priv *p = platform_get_drvdata(pdev);
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struct sh_timer_config *cfg = pdev->dev.platform_data;
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int ret;
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if (!is_early_platform_device(pdev)) {
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pm_runtime_set_active(&pdev->dev);
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pm_runtime_enable(&pdev->dev);
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}
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if (p) {
|
|
dev_info(&pdev->dev, "kept as earlytimer\n");
|
|
goto out;
|
|
}
|
|
|
|
p = kmalloc(sizeof(*p), GFP_KERNEL);
|
|
if (p == NULL) {
|
|
dev_err(&pdev->dev, "failed to allocate driver data\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
ret = sh_tmu_setup(p, pdev);
|
|
if (ret) {
|
|
kfree(p);
|
|
pm_runtime_idle(&pdev->dev);
|
|
return ret;
|
|
}
|
|
if (is_early_platform_device(pdev))
|
|
return 0;
|
|
|
|
out:
|
|
if (cfg->clockevent_rating || cfg->clocksource_rating)
|
|
pm_runtime_irq_safe(&pdev->dev);
|
|
else
|
|
pm_runtime_idle(&pdev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sh_tmu_remove(struct platform_device *pdev)
|
|
{
|
|
return -EBUSY; /* cannot unregister clockevent and clocksource */
|
|
}
|
|
|
|
static struct platform_driver sh_tmu_device_driver = {
|
|
.probe = sh_tmu_probe,
|
|
.remove = sh_tmu_remove,
|
|
.driver = {
|
|
.name = "sh_tmu",
|
|
}
|
|
};
|
|
|
|
static int __init sh_tmu_init(void)
|
|
{
|
|
return platform_driver_register(&sh_tmu_device_driver);
|
|
}
|
|
|
|
static void __exit sh_tmu_exit(void)
|
|
{
|
|
platform_driver_unregister(&sh_tmu_device_driver);
|
|
}
|
|
|
|
early_platform_init("earlytimer", &sh_tmu_device_driver);
|
|
subsys_initcall(sh_tmu_init);
|
|
module_exit(sh_tmu_exit);
|
|
|
|
MODULE_AUTHOR("Magnus Damm");
|
|
MODULE_DESCRIPTION("SuperH TMU Timer Driver");
|
|
MODULE_LICENSE("GPL v2");
|