clocksource: sh_tmu: Add index to struct sh_tmu_channel

Use the index as the timer start/stop bit and when printing messages to
identify the channel.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

drivers/clocksource/sh_tmu.c

@@ -39,6 +39,7 @@ struct sh_tmu_device;
 
 struct sh_tmu_channel {
 	struct sh_tmu_device *tmu;
+	unsigned int index;
 
 	void __iomem *base;
 	int irq;
@@ -102,7 +103,6 @@ static inline void sh_tmu_write(struct sh_tmu_channel *ch, int reg_nr,
 
 static void sh_tmu_start_stop_ch(struct sh_tmu_channel *ch, int start)
 {
-	struct sh_timer_config *cfg = ch->tmu->pdev->dev.platform_data;
 	unsigned long flags, value;
 
 	/* start stop register shared by multiple timer channels */
@@ -110,9 +110,9 @@ static void sh_tmu_start_stop_ch(struct sh_tmu_channel *ch, int start)
 	value = sh_tmu_read(ch, TSTR);
 
 	if (start)
-		value |= 1 << cfg->timer_bit;
+		value |= 1 << ch->index;
 	else
-		value &= ~(1 << cfg->timer_bit);
+		value &= ~(1 << ch->index);
 
 	sh_tmu_write(ch, TSTR, value);
 	raw_spin_unlock_irqrestore(&sh_tmu_lock, flags);
@@ -125,7 +125,8 @@ static int __sh_tmu_enable(struct sh_tmu_channel *ch)
 	/* enable clock */
 	ret = clk_enable(ch->tmu->clk);
 	if (ret) {
-		dev_err(&ch->tmu->pdev->dev, "cannot enable clock\n");
+		dev_err(&ch->tmu->pdev->dev, "ch%u: cannot enable clock\n",
+			ch->index);
 		return ret;
 	}
 
@@ -303,7 +304,8 @@ static int sh_tmu_register_clocksource(struct sh_tmu_channel *ch,
 	cs->mask = CLOCKSOURCE_MASK(32);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
 
-	dev_info(&ch->tmu->pdev->dev, "used as clock source\n");
+	dev_info(&ch->tmu->pdev->dev, "ch%u: used as clock source\n",
+		 ch->index);
 
 	/* Register with dummy 1 Hz value, gets updated in ->enable() */
 	clocksource_register_hz(cs, 1);
@@ -349,12 +351,12 @@ static void sh_tmu_clock_event_mode(enum clock_event_mode mode,
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		dev_info(&ch->tmu->pdev->dev,
-			 "used for periodic clock events\n");
+			 "ch%u: used for periodic clock events\n", ch->index);
 		sh_tmu_clock_event_start(ch, 1);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		dev_info(&ch->tmu->pdev->dev,
-			 "used for oneshot clock events\n");
+			 "ch%u: used for oneshot clock events\n", ch->index);
 		sh_tmu_clock_event_start(ch, 0);
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
@@ -407,7 +409,8 @@ static void sh_tmu_register_clockevent(struct sh_tmu_channel *ch,
 	ced->suspend = sh_tmu_clock_event_suspend;
 	ced->resume = sh_tmu_clock_event_resume;
 
-	dev_info(&ch->tmu->pdev->dev, "used for clock events\n");
+	dev_info(&ch->tmu->pdev->dev, "ch%u: used for clock events\n",
+		 ch->index);
 
 	clockevents_config_and_register(ced, 1, 0x300, 0xffffffff);
 
@@ -415,8 +418,8 @@ static void sh_tmu_register_clockevent(struct sh_tmu_channel *ch,
 			  IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
 			  dev_name(&ch->tmu->pdev->dev), ch);
 	if (ret) {
-		dev_err(&ch->tmu->pdev->dev, "failed to request irq %d\n",
-			ch->irq);
+		dev_err(&ch->tmu->pdev->dev, "ch%u: failed to request irq %d\n",
+			ch->index, ch->irq);
 		return;
 	}
 }
@@ -441,9 +444,19 @@ static int sh_tmu_channel_setup(struct sh_tmu_channel *ch,
 	memset(ch, 0, sizeof(*ch));
 	ch->tmu = tmu;
 
+	/*
+	 * The SH3 variant (SH770x, SH7705, SH7710 and SH7720) maps channel
+	 * registers blocks at base + 2 + 12 * index, while all other variants
+	 * map them at base + 4 + 12 * index. We can compute the index by just
+	 * dividing by 12, the 2 bytes or 4 bytes offset being hidden by the
+	 * integer division.
+	 */
+	ch->index = cfg->channel_offset / 12;
+
 	ch->irq = platform_get_irq(tmu->pdev, 0);
 	if (ch->irq < 0) {
-		dev_err(&tmu->pdev->dev, "failed to get irq\n");
+		dev_err(&tmu->pdev->dev, "ch%u: failed to get irq\n",
+			ch->index);
 		return ch->irq;
 	}