[PATCH v3 04/15] can: grcan: Add clock handling

Arun Muthusamy
2026-01-22T12:10:54Z

From: Daniel Hellstrom <daniel@gaisler.com>

Add clock handling and add error messages for missing 'freq' DT property.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: Arun Muthusamy <arun.muthusamy@gaisler.com>
---
drivers/net/can/grcan.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/grcan.c b/drivers/net/can/grcan.c
index 3b1b09943436..538a9b4f82ab 100644
--- a/drivers/net/can/grcan.c
+++ b/drivers/net/can/grcan.c
@@ -34,7 +34,7 @@
#include <linux/spinlock.h>
#include <linux/of.h>
#include <linux/of_irq.h>
-
+#include <linux/clk.h>
#include <linux/dma-mapping.h>

#define DRV_NAME "grcan"
@@ -1644,6 +1644,7 @@ static int grcan_probe(struct platform_device *ofdev)
{
struct device_node *np = ofdev->dev.of_node;
struct device_node *sysid_parent;
+ struct clk *clk;
u32 sysid, ambafreq;
int irq, err;
void __iomem *base;
@@ -1663,8 +1664,20 @@ static int grcan_probe(struct platform_device *ofdev)

err = of_property_read_u32(np, "freq", &ambafreq);
if (err) {
- dev_err(&ofdev->dev, "unable to fetch \"freq\" property\n");
- goto exit_error;
+ clk = devm_clk_get(&ofdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err_probe(&ofdev->dev, PTR_ERR(clk),
+ "Failed both to get \"freq\" property and clock for fallback\n");
+ err = PTR_ERR(clk);
+ goto exit_error;
+ }
+ if (clk) {
+ ambafreq = clk_get_rate(clk);
+ if (!ambafreq) {
+ dev_err(&ofdev->dev, "Invalid or Uninitialized clock\n");
+ return -EINVAL;
+ }
+ }
}

base = devm_platform_ioremap_resource(ofdev, 0);
--
2.51.0