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From: daniel.lezcano@linaro.org (Daniel Lezcano)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 38/71] clocksource: sh_mtu2: Split channel fields from sh_mtu2_priv
Date: Fri, 23 May 2014 12:31:18 +0200	[thread overview]
Message-ID: <1400841111-6683-38-git-send-email-daniel.lezcano@linaro.org> (raw)
In-Reply-To: <1400841111-6683-1-git-send-email-daniel.lezcano@linaro.org>

From: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Create a new sh_mtu2_channel structure to hold the channel-specific
fields in preparation for multiple channels per device support.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Wolfram Sang <wsa@sang-engineering.com>
---
 drivers/clocksource/sh_mtu2.c |  125 +++++++++++++++++++++++------------------
 1 file changed, 69 insertions(+), 56 deletions(-)

diff --git a/drivers/clocksource/sh_mtu2.c b/drivers/clocksource/sh_mtu2.c
index 6668455..e509f41 100644
--- a/drivers/clocksource/sh_mtu2.c
+++ b/drivers/clocksource/sh_mtu2.c
@@ -34,12 +34,21 @@
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 
+struct sh_mtu2_priv;
+
+struct sh_mtu2_channel {
+	struct sh_mtu2_priv *mtu;
+	int irq;
+	struct clock_event_device ced;
+};
+
 struct sh_mtu2_priv {
+	struct platform_device *pdev;
+
 	void __iomem *mapbase;
 	struct clk *clk;
-	int irq;
-	struct platform_device *pdev;
-	struct clock_event_device ced;
+
+	struct sh_mtu2_channel channel;
 };
 
 static DEFINE_RAW_SPINLOCK(sh_mtu2_lock);
@@ -63,10 +72,10 @@ static unsigned long mtu2_reg_offs[] = {
 	[TGR] = 8,
 };
 
-static inline unsigned long sh_mtu2_read(struct sh_mtu2_priv *p, int reg_nr)
+static inline unsigned long sh_mtu2_read(struct sh_mtu2_channel *ch, int reg_nr)
 {
-	struct sh_timer_config *cfg = p->pdev->dev.platform_data;
-	void __iomem *base = p->mapbase;
+	struct sh_timer_config *cfg = ch->mtu->pdev->dev.platform_data;
+	void __iomem *base = ch->mtu->mapbase;
 	unsigned long offs;
 
 	if (reg_nr == TSTR)
@@ -80,11 +89,11 @@ static inline unsigned long sh_mtu2_read(struct sh_mtu2_priv *p, int reg_nr)
 		return ioread8(base + offs);
 }
 
-static inline void sh_mtu2_write(struct sh_mtu2_priv *p, int reg_nr,
+static inline void sh_mtu2_write(struct sh_mtu2_channel *ch, int reg_nr,
 				unsigned long value)
 {
-	struct sh_timer_config *cfg = p->pdev->dev.platform_data;
-	void __iomem *base = p->mapbase;
+	struct sh_timer_config *cfg = ch->mtu->pdev->dev.platform_data;
+	void __iomem *base = ch->mtu->mapbase;
 	unsigned long offs;
 
 	if (reg_nr == TSTR) {
@@ -100,100 +109,100 @@ static inline void sh_mtu2_write(struct sh_mtu2_priv *p, int reg_nr,
 		iowrite8(value, base + offs);
 }
 
-static void sh_mtu2_start_stop_ch(struct sh_mtu2_priv *p, int start)
+static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start)
 {
-	struct sh_timer_config *cfg = p->pdev->dev.platform_data;
+	struct sh_timer_config *cfg = ch->mtu->pdev->dev.platform_data;
 	unsigned long flags, value;
 
 	/* start stop register shared by multiple timer channels */
 	raw_spin_lock_irqsave(&sh_mtu2_lock, flags);
-	value = sh_mtu2_read(p, TSTR);
+	value = sh_mtu2_read(ch, TSTR);
 
 	if (start)
 		value |= 1 << cfg->timer_bit;
 	else
 		value &= ~(1 << cfg->timer_bit);
 
-	sh_mtu2_write(p, TSTR, value);
+	sh_mtu2_write(ch, TSTR, value);
 	raw_spin_unlock_irqrestore(&sh_mtu2_lock, flags);
 }
 
-static int sh_mtu2_enable(struct sh_mtu2_priv *p)
+static int sh_mtu2_enable(struct sh_mtu2_channel *ch)
 {
 	unsigned long periodic;
 	unsigned long rate;
 	int ret;
 
-	pm_runtime_get_sync(&p->pdev->dev);
-	dev_pm_syscore_device(&p->pdev->dev, true);
+	pm_runtime_get_sync(&ch->mtu->pdev->dev);
+	dev_pm_syscore_device(&ch->mtu->pdev->dev, true);
 
 	/* enable clock */
-	ret = clk_enable(p->clk);
+	ret = clk_enable(ch->mtu->clk);
 	if (ret) {
-		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		dev_err(&ch->mtu->pdev->dev, "cannot enable clock\n");
 		return ret;
 	}
 
 	/* make sure channel is disabled */
-	sh_mtu2_start_stop_ch(p, 0);
+	sh_mtu2_start_stop_ch(ch, 0);
 
-	rate = clk_get_rate(p->clk) / 64;
+	rate = clk_get_rate(ch->mtu->clk) / 64;
 	periodic = (rate + HZ/2) / HZ;
 
 	/* "Periodic Counter Operation" */
-	sh_mtu2_write(p, TCR, 0x23); /* TGRA clear, divide clock by 64 */
-	sh_mtu2_write(p, TIOR, 0);
-	sh_mtu2_write(p, TGR, periodic);
-	sh_mtu2_write(p, TCNT, 0);
-	sh_mtu2_write(p, TMDR, 0);
-	sh_mtu2_write(p, TIER, 0x01);
+	sh_mtu2_write(ch, TCR, 0x23); /* TGRA clear, divide clock by 64 */
+	sh_mtu2_write(ch, TIOR, 0);
+	sh_mtu2_write(ch, TGR, periodic);
+	sh_mtu2_write(ch, TCNT, 0);
+	sh_mtu2_write(ch, TMDR, 0);
+	sh_mtu2_write(ch, TIER, 0x01);
 
 	/* enable channel */
-	sh_mtu2_start_stop_ch(p, 1);
+	sh_mtu2_start_stop_ch(ch, 1);
 
 	return 0;
 }
 
-static void sh_mtu2_disable(struct sh_mtu2_priv *p)
+static void sh_mtu2_disable(struct sh_mtu2_channel *ch)
 {
 	/* disable channel */
-	sh_mtu2_start_stop_ch(p, 0);
+	sh_mtu2_start_stop_ch(ch, 0);
 
 	/* stop clock */
-	clk_disable(p->clk);
+	clk_disable(ch->mtu->clk);
 
-	dev_pm_syscore_device(&p->pdev->dev, false);
-	pm_runtime_put(&p->pdev->dev);
+	dev_pm_syscore_device(&ch->mtu->pdev->dev, false);
+	pm_runtime_put(&ch->mtu->pdev->dev);
 }
 
 static irqreturn_t sh_mtu2_interrupt(int irq, void *dev_id)
 {
-	struct sh_mtu2_priv *p = dev_id;
+	struct sh_mtu2_channel *ch = dev_id;
 
 	/* acknowledge interrupt */
-	sh_mtu2_read(p, TSR);
-	sh_mtu2_write(p, TSR, 0xfe);
+	sh_mtu2_read(ch, TSR);
+	sh_mtu2_write(ch, TSR, 0xfe);
 
 	/* notify clockevent layer */
-	p->ced.event_handler(&p->ced);
+	ch->ced.event_handler(&ch->ced);
 	return IRQ_HANDLED;
 }
 
-static struct sh_mtu2_priv *ced_to_sh_mtu2(struct clock_event_device *ced)
+static struct sh_mtu2_channel *ced_to_sh_mtu2(struct clock_event_device *ced)
 {
-	return container_of(ced, struct sh_mtu2_priv, ced);
+	return container_of(ced, struct sh_mtu2_channel, ced);
 }
 
 static void sh_mtu2_clock_event_mode(enum clock_event_mode mode,
 				    struct clock_event_device *ced)
 {
-	struct sh_mtu2_priv *p = ced_to_sh_mtu2(ced);
+	struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
 	int disabled = 0;
 
 	/* deal with old setting first */
 	switch (ced->mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
-		sh_mtu2_disable(p);
+		sh_mtu2_disable(ch);
 		disabled = 1;
 		break;
 	default:
@@ -202,12 +211,13 @@ static void sh_mtu2_clock_event_mode(enum clock_event_mode mode,
 
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
-		dev_info(&p->pdev->dev, "used for periodic clock events\n");
-		sh_mtu2_enable(p);
+		dev_info(&ch->mtu->pdev->dev,
+			 "used for periodic clock events\n");
+		sh_mtu2_enable(ch);
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 		if (!disabled)
-			sh_mtu2_disable(p);
+			sh_mtu2_disable(ch);
 		break;
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	default:
@@ -217,18 +227,18 @@ static void sh_mtu2_clock_event_mode(enum clock_event_mode mode,
 
 static void sh_mtu2_clock_event_suspend(struct clock_event_device *ced)
 {
-	pm_genpd_syscore_poweroff(&ced_to_sh_mtu2(ced)->pdev->dev);
+	pm_genpd_syscore_poweroff(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
 }
 
 static void sh_mtu2_clock_event_resume(struct clock_event_device *ced)
 {
-	pm_genpd_syscore_poweron(&ced_to_sh_mtu2(ced)->pdev->dev);
+	pm_genpd_syscore_poweron(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
 }
 
-static void sh_mtu2_register_clockevent(struct sh_mtu2_priv *p,
+static void sh_mtu2_register_clockevent(struct sh_mtu2_channel *ch,
 				       char *name, unsigned long rating)
 {
-	struct clock_event_device *ced = &p->ced;
+	struct clock_event_device *ced = &ch->ced;
 	int ret;
 
 	memset(ced, 0, sizeof(*ced));
@@ -241,23 +251,24 @@ static void sh_mtu2_register_clockevent(struct sh_mtu2_priv *p,
 	ced->suspend = sh_mtu2_clock_event_suspend;
 	ced->resume = sh_mtu2_clock_event_resume;
 
-	dev_info(&p->pdev->dev, "used for clock events\n");
+	dev_info(&ch->mtu->pdev->dev, "used for clock events\n");
 	clockevents_register_device(ced);
 
-	ret = request_irq(p->irq, sh_mtu2_interrupt,
+	ret = request_irq(ch->irq, sh_mtu2_interrupt,
 			  IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
-			  dev_name(&p->pdev->dev), p);
+			  dev_name(&ch->mtu->pdev->dev), ch);
 	if (ret) {
-		dev_err(&p->pdev->dev, "failed to request irq %d\n", p->irq);
+		dev_err(&ch->mtu->pdev->dev, "failed to request irq %d\n",
+			ch->irq);
 		return;
 	}
 }
 
-static int sh_mtu2_register(struct sh_mtu2_priv *p, char *name,
+static int sh_mtu2_register(struct sh_mtu2_channel *ch, char *name,
 			    unsigned long clockevent_rating)
 {
 	if (clockevent_rating)
-		sh_mtu2_register_clockevent(p, name, clockevent_rating);
+		sh_mtu2_register_clockevent(ch, name, clockevent_rating);
 
 	return 0;
 }
@@ -285,8 +296,8 @@ static int sh_mtu2_setup(struct sh_mtu2_priv *p, struct platform_device *pdev)
 		goto err0;
 	}
 
-	p->irq = platform_get_irq(p->pdev, 0);
-	if (p->irq < 0) {
+	p->channel.irq = platform_get_irq(p->pdev, 0);
+	if (p->channel.irq < 0) {
 		dev_err(&p->pdev->dev, "failed to get irq\n");
 		goto err0;
 	}
@@ -310,7 +321,9 @@ static int sh_mtu2_setup(struct sh_mtu2_priv *p, struct platform_device *pdev)
 	if (ret < 0)
 		goto err2;
 
-	ret = sh_mtu2_register(p, (char *)dev_name(&p->pdev->dev),
+	p->channel.mtu = p;
+
+	ret = sh_mtu2_register(&p->channel, (char *)dev_name(&p->pdev->dev),
 			       cfg->clockevent_rating);
 	if (ret < 0)
 		goto err3;
-- 
1.7.9.5

  parent reply	other threads:[~2014-05-23 10:31 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-23 10:22 [GIT PULL] clockevents: new material for 3.16 Daniel Lezcano
2014-05-23 10:30 ` [PATCH 01/71] clocksource: sh_cmt: Use request_irq() instead of setup_irq() Daniel Lezcano
2014-05-23 10:30   ` [PATCH 02/71] clocksource: sh_cmt: Split channel fields from sh_cmt_priv Daniel Lezcano
2014-05-23 10:30   ` [PATCH 03/71] clocksource: sh_cmt: Rename struct sh_cmt_priv to sh_cmt_device Daniel Lezcano
2014-05-23 10:30   ` [PATCH 04/71] clocksource: sh_cmt: Split channel setup to separate function Daniel Lezcano
2014-05-23 10:30   ` [PATCH 05/71] clocksource: sh_cmt: Constify name argument to sh_cmt_register() Daniel Lezcano
2014-05-23 10:30   ` [PATCH 06/71] clocksource: sh_cmt: Rename mapbase/mapbase_str to mapbase_ch/mapbase Daniel Lezcano
2014-05-23 10:30   ` [PATCH 07/71] clocksource: sh_cmt: Add memory base to sh_cmt_channel structure Daniel Lezcano
2014-05-23 10:30   ` [PATCH 08/71] clocksource: sh_cmt: Add index to struct sh_cmt_channel Daniel Lezcano
2014-05-23 10:30   ` [PATCH 09/71] clocksource: sh_cmt: Replace kmalloc + memset with kzalloc Daniel Lezcano
2014-05-23 10:30   ` [PATCH 10/71] clocksource: sh_cmt: Allocate channels dynamically Daniel Lezcano
2014-05-23 10:30   ` [PATCH 11/71] clocksource: sh_cmt: Split static information from sh_cmt_device Daniel Lezcano
2014-05-23 10:30   ` [PATCH 12/71] clocksource: sh_cmt: Replace hardcoded register values with macros Daniel Lezcano
2014-05-23 10:30   ` [PATCH 13/71] clocksource: sh_cmt: Set cpumask to cpu_possible_mask Daniel Lezcano
2014-05-23 10:30   ` [PATCH 14/71] clocksource: sh_cmt: Hardcode CMT clock event rating to 125 Daniel Lezcano
2014-05-23 10:30   ` [PATCH 15/71] clocksource: sh_cmt: Hardcode CMT clock source " Daniel Lezcano
2014-05-23 10:30   ` [PATCH 16/71] clocksource: sh_cmt: Add support for multiple channels per device Daniel Lezcano
2014-05-23 10:30   ` [PATCH 17/71] clocksource: sh_cmt: Rename clock to "fck" in the non-legacy case Daniel Lezcano
2014-05-23 10:30   ` [PATCH 18/71] clocksource: sh_cmt: Remove FSF mail address from GPL notice Daniel Lezcano
2014-05-23 10:30   ` [PATCH 19/71] clocksource: sh_cmt: Sort headers alphabetically Daniel Lezcano
2014-05-23 10:31   ` [PATCH 20/71] clocksource: sh_cmt: Request IRQ for clock event device only Daniel Lezcano
2014-05-23 10:31   ` [PATCH 21/71] clocksource: sh_tmu: Use request_irq() instead of setup_irq() Daniel Lezcano
2014-05-23 10:31   ` [PATCH 22/71] clocksource: sh_tmu: Split channel fields from sh_tmu_priv Daniel Lezcano
2014-05-23 10:31   ` [PATCH 23/71] clocksource: sh_tmu: Rename struct sh_tmu_priv to sh_tmu_device Daniel Lezcano
2014-05-23 10:31   ` [PATCH 24/71] clocksource: sh_tmu: Split channel setup to separate function Daniel Lezcano
2014-05-23 10:31   ` [PATCH 25/71] clocksource: sh_tmu: Constify name argument to sh_tmu_register() Daniel Lezcano
2014-05-23 10:31   ` [PATCH 26/71] clocksource: sh_tmu: Add memory base to sh_tmu_channel structure Daniel Lezcano
2014-05-23 10:31   ` [PATCH 27/71] clocksource: sh_tmu: Add index to struct sh_tmu_channel Daniel Lezcano
2014-05-23 10:31   ` [PATCH 28/71] clocksource: sh_tmu: Replace kmalloc + memset with kzalloc Daniel Lezcano
2014-05-23 10:31   ` [PATCH 29/71] clocksource: sh_tmu: Allocate channels dynamically Daniel Lezcano
2014-05-23 10:31   ` [PATCH 30/71] clocksource: sh_tmu: Replace hardcoded register values with macros Daniel Lezcano
2014-05-23 10:31   ` [PATCH 31/71] clocksource: sh_tmu: Hardcode TMU clock event and source ratings to 200 Daniel Lezcano
2014-05-23 10:31   ` [PATCH 32/71] clocksource: sh_tmu: Add support for multiple channels per device Daniel Lezcano
2014-05-23 10:31   ` [PATCH 33/71] clocksource: sh_tmu: Rename clock to "fck" in the non-legacy case Daniel Lezcano
2014-05-23 10:31   ` [PATCH 34/71] clocksource: sh_tmu: Remove FSF mail address from GPL notice Daniel Lezcano
2014-05-23 10:31   ` [PATCH 35/71] clocksource: sh_tmu: Sort headers alphabetically Daniel Lezcano
2014-05-23 10:31   ` [PATCH 36/71] clocksource: sh_mtu2: Use request_irq() instead of setup_irq() Daniel Lezcano
2014-05-23 10:31   ` [PATCH 37/71] clocksource: sh_mtu2: Turn sh_mtu2_priv fields into local variables Daniel Lezcano
2014-05-23 10:31   ` Daniel Lezcano [this message]
2014-05-23 10:31   ` [PATCH 39/71] clocksource: sh_mtu2: Rename struct sh_mtu2_priv to sh_mtu2_device Daniel Lezcano
2014-05-23 10:31   ` [PATCH 40/71] clocksource: sh_mtu2: Split channel setup to separate function Daniel Lezcano
2014-05-23 10:31   ` [PATCH 41/71] clocksource: sh_mtu2: Constify name argument to sh_mtu2_register() Daniel Lezcano
2014-05-23 10:31   ` [PATCH 42/71] clocksource: sh_mtu2: Add memory base to sh_mtu2_channel structure Daniel Lezcano
2014-05-23 10:31   ` [PATCH 43/71] clocksource: sh_mtu2: Add index to struct sh_mtu2_channel Daniel Lezcano
2014-05-23 10:31   ` [PATCH 44/71] clocksource: sh_mtu2: Replace kmalloc + memset with kzalloc Daniel Lezcano
2014-05-23 10:31   ` [PATCH 45/71] clocksource: sh_mtu2: Allocate channels dynamically Daniel Lezcano
2014-05-23 10:31   ` [PATCH 46/71] clocksource: sh_mtu2: Replace hardcoded register values with macros Daniel Lezcano
2014-05-23 10:31   ` [PATCH 47/71] clocksource: sh_mtu2: Set cpumask to cpu_possible_mask Daniel Lezcano
2014-05-23 10:31   ` [PATCH 48/71] clocksource: sh_mtu2: Hardcode MTU2 clock event rating to 200 Daniel Lezcano
2014-05-23 10:31   ` [PATCH 49/71] clocksource: sh_mtu2: Add support for multiple channels per device Daniel Lezcano
2014-05-23 10:31   ` [PATCH 50/71] clocksource: sh_mtu2: Rename clock to "fck" in the non-legacy case Daniel Lezcano
2014-05-23 10:31   ` [PATCH 51/71] clocksource: sh_mtu2: Remove FSF mail address from GPL notice Daniel Lezcano
2014-05-23 10:31   ` [PATCH 52/71] clocksource: sh_mtu2: Sort headers alphabetically Daniel Lezcano
2014-05-23 10:31   ` [PATCH 53/71] clocksource: arm_global_timer: Only check for unusable timer on A9 Daniel Lezcano
2014-05-23 10:31   ` [PATCH 54/71] documentaion: DT: allow a A5 compatible string in global timer Daniel Lezcano
2014-05-23 10:31   ` [PATCH 55/71] dts: ca5: add the global timer for the A5 Daniel Lezcano
2014-05-23 10:31   ` [PATCH 56/71] KConfig: Vexpress: build the ARM_GLOBAL_TIMER with vexpress platform Daniel Lezcano
2014-05-23 10:31   ` [PATCH 57/71] clocksource: efm32: use $vendor, $device scheme for compatible string Daniel Lezcano
2014-05-23 10:31   ` [PATCH 58/71] clocksource: sun5i: Add support for reset controller Daniel Lezcano
2014-05-23 10:31   ` [PATCH 59/71] ARM: sun6i: a31: Add support for the High Speed Timers Daniel Lezcano
2014-05-23 10:31   ` [PATCH 60/71] clocksource: qcom: Implement read_current_timer for udelay Daniel Lezcano
2014-05-23 10:31   ` [PATCH 61/71] clocksource: sh_tmu: Fix channel IRQ retrieval in legacy case Daniel Lezcano
2014-05-23 10:31   ` [PATCH 62/71] clocksource: Fix type confusion for clocksource_mmio_readX_Y Daniel Lezcano
2014-05-23 10:31   ` [PATCH 63/71] clocksource: Fix clocksource_mmio_readX_down Daniel Lezcano
2014-05-23 10:31   ` [PATCH 64/71] clocksource: dw_apb_timer_of: Do not trace read_sched_clock Daniel Lezcano
2014-05-23 10:31   ` [PATCH 65/71] clocksource: em_sti: Remove unnecessary OOM messages Daniel Lezcano
2014-05-23 10:31   ` [PATCH 66/71] clocksource: sh_cmt: " Daniel Lezcano
2014-05-23 10:31   ` [PATCH 67/71] clocksource: sh_mtu2: " Daniel Lezcano
2014-05-23 10:31   ` [PATCH 68/71] clocksource: sh_tmu: " Daniel Lezcano
2014-05-23 10:31   ` [PATCH 69/71] clocksource: ftm: Add FlexTimer Module (FTM) Timer devicetree Documentation Daniel Lezcano
2014-05-23 10:31   ` [PATCH 70/71] ARM: dts: vf610: Add Freescale FlexTimer Module timer node Daniel Lezcano
2014-05-23 10:31   ` [PATCH 71/71] clocksource: Add Freescale FlexTimer Module (FTM) timer support Daniel Lezcano
     [not found] ` <20140526194512.032c6630@canb.auug.org.au>
2014-05-26  9:52   ` [GIT PULL] clockevents: new material for 3.16 Daniel Lezcano
2014-05-26 13:40     ` Maxime Ripard
2014-05-26 15:07       ` Philipp Zabel

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