[PATCH net-next 17/37] can: rcar_canfd: Derive max_channels from the device tree

[Marc Kleine-Budde <mkl@pengutronix.de>]

From: Biju Das <biju.das.jz@bp.renesas.com>

The maximum number of channels is currently hardcoded per SoC in
struct rcar_canfd_hw_info. Since the DT describes the channels as
child nodes of the controller, the count can be obtained at probe time
with of_get_child_count() instead.

Drop max_channels from struct rcar_canfd_hw_info and store the value
in struct rcar_canfd_global, so it no longer needs to be maintained
for each SoC variant. Update all for_each_set_bit() users over
channels_mask to use gpriv->max_channels.

No functional change.

Reviewed-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://patch.msgid.link/20261001075742.21961-3-biju.das.jz@bp.renesas.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/rcar/rcar_canfd.c | 39 +++++++++++++++----------------
 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 74c3c3f20991..41c395118949 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -436,7 +436,6 @@ struct rcar_canfd_hw_info {
 	u8 rnc_field_width;
 	u8 max_aflpn;
 	u8 max_cftml;
-	u8 max_channels;
 	u8 postdiv;
 	/* hardware features */
 	unsigned shared_global_irqs:1;	/* Has shared global irqs */
@@ -478,6 +477,7 @@ struct rcar_canfd_global {
 	struct reset_control *rstc1;
 	struct reset_control *rstc2;
 	const struct rcar_canfd_hw_info *info;
+	u8 max_channels;
 };
 
 /* CAN FD mode nominal rate constants */
@@ -613,7 +613,6 @@ static const struct rcar_canfd_hw_info rcar_gen3_hw_info = {
 	.rnc_field_width = 8,
 	.max_aflpn = 31,
 	.max_cftml = 15,
-	.max_channels = 2,
 	.postdiv = 2,
 	.shared_global_irqs = 1,
 	.ch_interface_mode = 0,
@@ -632,7 +631,6 @@ static const struct rcar_canfd_hw_info rcar_gen4_hw_info = {
 	.rnc_field_width = 16,
 	.max_aflpn = 127,
 	.max_cftml = 31,
-	.max_channels = 8,
 	.postdiv = 2,
 	.shared_global_irqs = 1,
 	.ch_interface_mode = 1,
@@ -651,7 +649,6 @@ static const struct rcar_canfd_hw_info rzg2l_hw_info = {
 	.rnc_field_width = 8,
 	.max_aflpn = 31,
 	.max_cftml = 15,
-	.max_channels = 2,
 	.postdiv = 1,
 	.multi_channel_irqs = 1,
 	.ch_interface_mode = 0,
@@ -670,7 +667,6 @@ static const struct rcar_canfd_hw_info r9a08g045_hw_info = {
 	.rnc_field_width = 16,
 	.max_aflpn = 15,
 	.max_cftml = 31,
-	.max_channels = 2,
 	.postdiv = 2,
 	.shared_global_irqs = 0,
 	.multi_channel_irqs = 1,
@@ -690,7 +686,6 @@ static const struct rcar_canfd_hw_info r9a09g047_hw_info = {
 	.rnc_field_width = 16,
 	.max_aflpn = 63,
 	.max_cftml = 31,
-	.max_channels = 6,
 	.postdiv = 1,
 	.multi_channel_irqs = 1,
 	.ch_interface_mode = 1,
@@ -709,7 +704,6 @@ static const struct rcar_canfd_hw_info r9a09g077_hw_info = {
 	.rnc_field_width = 16,
 	.max_aflpn = 15,
 	.max_cftml = 31,
-	.max_channels = 2,
 	.postdiv = 1,
 	.multi_channel_irqs = 1,
 	.ch_interface_mode = 1,
@@ -854,7 +848,7 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
 	}
 
 	/* Transition all Channels to reset mode */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		rcar_canfd_clear_bit(gpriv->base,
 				     RCANFD_CCTR(ch), RCANFD_CCTR_CSLPR);
 
@@ -922,7 +916,7 @@ static void rcar_canfd_configure_controller(struct rcar_canfd_global *gpriv)
 	rcar_canfd_set_bit(gpriv->base, RCANFD_GCFG, cfg);
 
 	/* Channel configuration settings */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		rcar_canfd_set_bit(gpriv->base, RCANFD_CCTR(ch),
 				   RCANFD_CCTR_ERRD);
 		rcar_canfd_update_bit(gpriv->base, RCANFD_CCTR(ch),
@@ -1293,7 +1287,7 @@ static irqreturn_t rcar_canfd_global_err_interrupt(int irq, void *dev_id)
 	struct rcar_canfd_global *gpriv = dev_id;
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels)
 		rcar_canfd_handle_global_err(gpriv, ch);
 
 	return IRQ_HANDLED;
@@ -1325,7 +1319,7 @@ static irqreturn_t rcar_canfd_global_receive_fifo_interrupt(int irq, void *dev_i
 	struct rcar_canfd_global *gpriv = dev_id;
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels)
 		rcar_canfd_handle_global_receive(gpriv, ch);
 
 	return IRQ_HANDLED;
@@ -1339,7 +1333,7 @@ static irqreturn_t rcar_canfd_global_interrupt(int irq, void *dev_id)
 	/* Global error interrupts still indicate a condition specific
 	 * to a channel. RxFIFO interrupt is a global interrupt.
 	 */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		rcar_canfd_handle_global_err(gpriv, ch);
 		rcar_canfd_handle_global_receive(gpriv, ch);
 	}
@@ -1435,7 +1429,7 @@ static irqreturn_t rcar_canfd_channel_interrupt(int irq, void *dev_id)
 	u32 ch;
 
 	/* Common FIFO is a per channel resource */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		rcar_canfd_handle_channel_err(gpriv, ch);
 		rcar_canfd_handle_channel_tx(gpriv, ch);
 	}
@@ -2072,7 +2066,7 @@ static int rcar_canfd_global_init(struct rcar_canfd_global *gpriv)
 	rcar_canfd_configure_controller(gpriv);
 
 	/* Configure per channel attributes */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		/* Configure Channel's Rx fifo */
 		rcar_canfd_configure_rx(gpriv, ch);
 
@@ -2145,14 +2139,18 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	bool fdmode = true;			/* CAN FD only mode - default */
 	char name[9] = "channelX";
 	u32 ch, fcan_freq;
+	u8 max_channels;
 	int i;
 
 	info = of_device_get_match_data(dev);
+	max_channels = of_get_child_count(dev->of_node);
+	if (max_channels > RCANFD_NUM_CHANNELS)
+		return -EINVAL;
 
 	if (of_property_read_bool(dev->of_node, "renesas,no-can-fd"))
 		fdmode = false;			/* Classical CAN only mode */
 
-	for (i = 0; i < info->max_channels; ++i) {
+	for (i = 0; i < max_channels; ++i) {
 		name[7] = '0' + i;
 		of_child = of_get_available_child_by_name(dev->of_node, name);
 		if (of_child) {
@@ -2199,6 +2197,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	gpriv->pdev = pdev;
 	gpriv->channels_mask = channels_mask;
 	gpriv->fdmode = fdmode;
+	gpriv->max_channels = max_channels;
 	gpriv->info = info;
 
 	if (of_property_read_bool(dev->of_node, "renesas,fd-only"))
@@ -2300,7 +2299,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	if (err)
 		goto fail_mode;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		err = rcar_canfd_channel_probe(gpriv, ch, fcan_freq,
 					       transceivers[ch]);
 		if (err)
@@ -2314,7 +2313,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	return 0;
 
 fail_channel:
-	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels)
 		rcar_canfd_channel_remove(gpriv, ch);
 fail_mode:
 	rcar_canfd_global_deinit(gpriv, false);
@@ -2327,7 +2326,7 @@ static void rcar_canfd_remove(struct platform_device *pdev)
 	struct rcar_canfd_global *gpriv = platform_get_drvdata(pdev);
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		rcar_canfd_disable_channel_interrupts(gpriv->ch[ch]);
 		rcar_canfd_channel_remove(gpriv, ch);
 	}
@@ -2341,7 +2340,7 @@ static int rcar_canfd_suspend(struct device *dev)
 	int err;
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		struct rcar_canfd_channel *priv = gpriv->ch[ch];
 		struct net_device *ndev = priv->ndev;
 
@@ -2378,7 +2377,7 @@ static int rcar_canfd_resume(struct device *dev)
 		return err;
 	}
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
 		struct rcar_canfd_channel *priv = gpriv->ch[ch];
 		struct net_device *ndev = priv->ndev;
 
-- 
2.53.0