Re: [PATCH v2 2/4] hwrng: stm32 - implement support for STM32MP25x platforms

From: Marek Vasut
Date: Mon Oct 14 2024 - 06:12:12 EST


On 10/14/24 10:38 AM, Gatien CHEVALLIER wrote:


On 10/11/24 18:17, Marek Vasut wrote:
On 10/11/24 5:41 PM, Gatien Chevallier wrote:

[...]

@@ -551,6 +565,41 @@ static int stm32_rng_probe(struct platform_device *ofdev)
      priv->rng.read = stm32_rng_read;
      priv->rng.quality = 900;
+    if (!priv->data->nb_clock || priv->data->nb_clock > 2)
+        return -EINVAL;
+
+    priv->clk_bulk = devm_kzalloc(dev, priv->data->nb_clock * sizeof(*priv->clk_bulk),
+                      GFP_KERNEL);
+    if (!priv->clk_bulk)
+        return -ENOMEM;

Try this:

ret = devm_clk_bulk_get(dev, priv->data->nb_clock, priv->clk_bulk);
...
// Swap the clock if they are not in the right order:
if (priv->data->nb_clock == 2 &&
     strcmp(__clk_get_name(priv->clk_bulk[0].clk), "core"))
{
  const char *id = priv->clk_bulk[1].id;
  struct clk *clk = priv->clk_bulk[1].clk;
  priv->clk_bulk[1].id = priv->clk_bulk[0].id;
  priv->clk_bulk[1].clk = priv->clk_bulk[0].clk;
  priv->clk_bulk[0].id = id;
  priv->clk_bulk[0].clk = clk;
}


Hi Marek,

This won't work as the name returned by this API is clk->core->name.
AFAICT, it doesn't correspond to the names present in the device tree
under the "clock-names" property.
Any other idea or are you fine with what's below?
Hmmm, it is not great, but at least it reduces the changes throughout the driver, so that is an improvement.

I guess one could do some of_clk_get() and clk_is_match() in probe to look up the clock in OF by name and then compare which clock is which before swapping them in clk_bulk[] array, but that might be too convoluted?