[PATCH v4 0/2] m68k: coldfire: Add RNG support for MCF54418

[PATCH v4 0/2] m68k: coldfire: Add RNG support for MCF54418

[Jean-Michel Hautbois via B4 Relay]

This series adds support for the MCF54418 hardware random number generator
(RNGB).

The MCF54418 contains an RNGB hardware block compatible with the imx-rngc
driver. This series enables its use by:
- Adding platform device registration for the RNG hardware
- Enabling the clock at platform initialization
- Making the imx-rngc driver compatible with Coldfire's always-on clock
model using devm_clk_get_optional()

Testing on DLC Next board shows:
- Hardware RNG throughput: 26 MB/s
- FIPS 140-2 quality: 0.2% failure rate (rng-tools)
- Boot time improvement: CRNG initialization 7 seconds faster

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
Changes in v4:
- Postpone const qualifiers for now
- Link to v3: https://lore.kernel.org/r/20251124-b4-m5441x-add-rng-support-v3-0-f447251dad27@yoseli.org

Changes in v3:
- Depend on COLDFIRE is enough
- Split the clock change in a dedicated commit
- Link to v2: https://lore.kernel.org/r/20251107-b4-m5441x-add-rng-support-v2-0-f91d685832b9@yoseli.org

Changes in v2:
- Split const qualifier changes into a separate patch as suggested by
Frank Li
- Mark all resource arrays (including RNG) as const in device.c
- No functional changes to RNG implementation

---
Jean-Michel Hautbois (2):
      hwrng: imx-rngc: Use optional clock
      m68k: coldfire: Add RNG support for MCF54418

 arch/m68k/coldfire/device.c       | 28 ++++++++++++++++++++++++++++
 arch/m68k/coldfire/m5441x.c       |  2 +-
 arch/m68k/include/asm/m5441xsim.h |  9 +++++++++
 drivers/char/hw_random/Kconfig    |  3 ++-
 drivers/char/hw_random/imx-rngc.c |  9 ++++++++-
 5 files changed, 48 insertions(+), 3 deletions(-)
---
base-commit: ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
change-id: 20251107-b4-m5441x-add-rng-support-0fdb8d40210a

Best regards,
--  
Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

[PATCH v4 1/2] hwrng: imx-rngc: Use optional clock

[Jean-Michel Hautbois via B4 Relay]

From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

Change devm_clk_get() to devm_clk_get_optional() to support platforms
where the RNG clock is always enabled and not exposed via the clock
framework (such as ColdFire MCF54418).

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
 drivers/char/hw_random/imx-rngc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 241664a9b5d9..d6a847e48339 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
 	if (IS_ERR(rngc->base))
 		return PTR_ERR(rngc->base);
 
-	rngc->clk = devm_clk_get(&pdev->dev, NULL);
+	rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
 	if (IS_ERR(rngc->clk))
 		return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");
 

-- 
2.39.5

Re: [PATCH v4 1/2] hwrng: imx-rngc: Use optional clock

[Martin Kaiser]

Thus wrote Jean-Michel Hautbois via B4 Relay (devnull+jeanmichel.hautbois.yoseli.org@kernel.org):

> From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

> Change devm_clk_get() to devm_clk_get_optional() to support platforms
> where the RNG clock is always enabled and not exposed via the clock
> framework (such as ColdFire MCF54418).

> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> ---
>  drivers/char/hw_random/imx-rngc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> index 241664a9b5d9..d6a847e48339 100644
> --- a/drivers/char/hw_random/imx-rngc.c
> +++ b/drivers/char/hw_random/imx-rngc.c
> @@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
>  	if (IS_ERR(rngc->base))
>  		return PTR_ERR(rngc->base);

> -	rngc->clk = devm_clk_get(&pdev->dev, NULL);
> +	rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
>  	if (IS_ERR(rngc->clk))
>  		return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");

The clock is not optional on a standard imx25 system. If it's missing in the
device tree, the rngb will not work and we should not load the driver.

Should we call devm_clk_get or devm_clk_get_optional, depending on the
detected device?

Best regards,
Martin

Re: [PATCH v4 1/2] hwrng: imx-rngc: Use optional clock

[Geert Uytterhoeven]

Hi Martin,

On Wed, 26 Nov 2025 at 21:30, Martin Kaiser <martin@kaiser.cx> wrote:
> Thus wrote Jean-Michel Hautbois via B4 Relay (devnull+jeanmichel.hautbois.yoseli.org@kernel.org):
>
> > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
>
> > Change devm_clk_get() to devm_clk_get_optional() to support platforms
> > where the RNG clock is always enabled and not exposed via the clock
> > framework (such as ColdFire MCF54418).
>
> > Reviewed-by: Frank Li <Frank.Li@nxp.com>
> > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > ---
> >  drivers/char/hw_random/imx-rngc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
>
> > diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> > index 241664a9b5d9..d6a847e48339 100644
> > --- a/drivers/char/hw_random/imx-rngc.c
> > +++ b/drivers/char/hw_random/imx-rngc.c
> > @@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
> >       if (IS_ERR(rngc->base))
> >               return PTR_ERR(rngc->base);
>
> > -     rngc->clk = devm_clk_get(&pdev->dev, NULL);
> > +     rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
> >       if (IS_ERR(rngc->clk))
> >               return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");
>
> The clock is not optional on a standard imx25 system. If it's missing in the
> device tree, the rngb will not work and we should not load the driver.

As the clocks property is marked required in
Documentation/devicetree/bindings/rng/imx-rng.yaml, "make dtbs_check"
should flag a missing clock.

> Should we call devm_clk_get or devm_clk_get_optional, depending on the
> detected device?

That can quickly lead to complex code.  Nowadays it is fine to rely on
"make dtbs_check" for some part of the validation.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v4 1/2] hwrng: imx-rngc: Use optional clock

[Martin Kaiser]

Hi Geert,

Thus wrote Geert Uytterhoeven (geert@linux-m68k.org):

> Hi Martin,

> On Wed, 26 Nov 2025 at 21:30, Martin Kaiser <martin@kaiser.cx> wrote:
> > Thus wrote Jean-Michel Hautbois via B4 Relay (devnull+jeanmichel.hautbois.yoseli.org@kernel.org):

> > > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

> > > Change devm_clk_get() to devm_clk_get_optional() to support platforms
> > > where the RNG clock is always enabled and not exposed via the clock
> > > framework (such as ColdFire MCF54418).

> > > Reviewed-by: Frank Li <Frank.Li@nxp.com>
> > > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > ---
> > >  drivers/char/hw_random/imx-rngc.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)

> > > diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> > > index 241664a9b5d9..d6a847e48339 100644
> > > --- a/drivers/char/hw_random/imx-rngc.c
> > > +++ b/drivers/char/hw_random/imx-rngc.c
> > > @@ -259,7 +259,7 @@ static int __init imx_rngc_probe(struct platform_device *pdev)
> > >       if (IS_ERR(rngc->base))
> > >               return PTR_ERR(rngc->base);

> > > -     rngc->clk = devm_clk_get(&pdev->dev, NULL);
> > > +     rngc->clk = devm_clk_get_optional(&pdev->dev, NULL);
> > >       if (IS_ERR(rngc->clk))
> > >               return dev_err_probe(&pdev->dev, PTR_ERR(rngc->clk), "Cannot get rng_clk\n");

> > The clock is not optional on a standard imx25 system. If it's missing in the
> > device tree, the rngb will not work and we should not load the driver.

> As the clocks property is marked required in
> Documentation/devicetree/bindings/rng/imx-rng.yaml, "make dtbs_check"
> should flag a missing clock.

> > Should we call devm_clk_get or devm_clk_get_optional, depending on the
> > detected device?

> That can quickly lead to complex code.  Nowadays it is fine to rely on
> "make dtbs_check" for some part of the validation.

ok, understood. With this clarification, I'm happy with the patch.

Reviewed-by: Martin Kaiser <martin@kaiser.cx>

Thanks,
Martin

[PATCH v4 2/2] m68k: coldfire: Add RNG support for MCF54418

[Jean-Michel Hautbois via B4 Relay]

From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

Add support for the hardware Random Number Generator (RNGB) found on
MCF54418 ColdFire processors with clock enabled at platform
initialization.

The RNGB block is compatible with the imx-rngc driver.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
 arch/m68k/coldfire/device.c       | 28 ++++++++++++++++++++++++++++
 arch/m68k/coldfire/m5441x.c       |  2 +-
 arch/m68k/include/asm/m5441xsim.h |  9 +++++++++
 drivers/char/hw_random/Kconfig    |  3 ++-
 drivers/char/hw_random/imx-rngc.c |  7 +++++++
 5 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
index b6958ec2a220..9d8f844e319a 100644
--- a/arch/m68k/coldfire/device.c
+++ b/arch/m68k/coldfire/device.c
@@ -622,6 +622,31 @@ static struct platform_device mcf_flexcan0 = {
 };
 #endif /* MCFFLEXCAN_SIZE */
 
+#ifdef MCF_RNG_BASE
+/*
+ * Random Number Generator (RNG) - only on MCF54418
+ */
+static struct resource mcf_rng_resource[] = {
+	{
+		.start = MCF_RNG_BASE,
+		.end   = MCF_RNG_BASE + MCF_RNG_SIZE - 1,
+		.flags = IORESOURCE_MEM,
+	},
+	{
+		.start = MCF_IRQ_RNG,
+		.end   = MCF_IRQ_RNG,
+		.flags = IORESOURCE_IRQ,
+	},
+};
+
+static struct platform_device mcf_rng = {
+	.name           = "imx-rngc",
+	.id             = -1,
+	.num_resources  = ARRAY_SIZE(mcf_rng_resource),
+	.resource       = mcf_rng_resource,
+};
+#endif /* MCF_RNG_BASE */
+
 static struct platform_device *mcf_devices[] __initdata = {
 	&mcf_uart,
 #ifdef MCFFEC_BASE0
@@ -660,6 +685,9 @@ static struct platform_device *mcf_devices[] __initdata = {
 #ifdef MCFFLEXCAN_SIZE
 	&mcf_flexcan0,
 #endif
+#ifdef MCF_RNG_BASE
+	&mcf_rng,
+#endif
 };
 
 /*
diff --git a/arch/m68k/coldfire/m5441x.c b/arch/m68k/coldfire/m5441x.c
index 7a25cfc7ac07..ab5b00637237 100644
--- a/arch/m68k/coldfire/m5441x.c
+++ b/arch/m68k/coldfire/m5441x.c
@@ -158,6 +158,7 @@ static struct clk * const enable_clks[] __initconst = {
 	&__clk_0_33, /* pit.1 */
 	&__clk_0_37, /* eport */
 	&__clk_0_48, /* pll */
+	&__clk_0_49, /* rng */
 	&__clk_0_51, /* esdhc */
 
 	&__clk_1_36, /* CCM/reset module/Power management */
@@ -179,7 +180,6 @@ static struct clk * const disable_clks[] __initconst = {
 	&__clk_0_44, /* usb otg */
 	&__clk_0_45, /* usb host */
 	&__clk_0_47, /* ssi.0 */
-	&__clk_0_49, /* rng */
 	&__clk_0_50, /* ssi.1 */
 	&__clk_0_53, /* enet-fec */
 	&__clk_0_54, /* enet-fec */
diff --git a/arch/m68k/include/asm/m5441xsim.h b/arch/m68k/include/asm/m5441xsim.h
index f48cf63bd782..dd64cdfcad3e 100644
--- a/arch/m68k/include/asm/m5441xsim.h
+++ b/arch/m68k/include/asm/m5441xsim.h
@@ -198,6 +198,15 @@
 #define MCFRTC_SIZE		(0xfc0a8840 - 0xfc0a8000)
 #define MCF_IRQ_RTC		(MCFINT2_VECBASE + MCFINT2_RTC)
 
+/*
+ *  Random Number Generator (RNG) Module.
+ *  Note: Only present in MCF54418, not in MCF54410/54415/54417
+ */
+#define MCF_RNG_BASE		0xfc0c4000
+#define MCF_RNG_SIZE		0x1c
+#define MCFINT2_RNG		28
+#define MCF_IRQ_RNG		(MCFINT2_VECBASE + MCFINT2_RNG)
+
 /*
  *  GPIO Module.
  */
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 492a2a61a65b..2f301e43db84 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -270,12 +270,13 @@ config HW_RANDOM_MXC_RNGA
 config HW_RANDOM_IMX_RNGC
 	tristate "Freescale i.MX RNGC Random Number Generator"
 	depends on HAS_IOMEM
-	depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COMPILE_TEST
+	depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COLDFIRE || COMPILE_TEST
 	default HW_RANDOM
 	help
 	  This driver provides kernel-side support for the Random Number
 	  Generator Version C hardware found on some Freescale i.MX
 	  processors. Version B is also supported by this driver.
+	  Also supports RNGB on Freescale MCF54418 (Coldfire V4e).
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called imx-rngc.
diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index d6a847e48339..44f20a05de0a 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -353,12 +353,19 @@ static const struct of_device_id imx_rngc_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, imx_rngc_dt_ids);
 
+static const struct platform_device_id imx_rngc_devtype[] = {
+	{ .name = "imx-rngc" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, imx_rngc_devtype);
+
 static struct platform_driver imx_rngc_driver = {
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.pm = pm_ptr(&imx_rngc_pm_ops),
 		.of_match_table = imx_rngc_dt_ids,
 	},
+	.id_table = imx_rngc_devtype,
 };
 
 module_platform_driver_probe(imx_rngc_driver, imx_rngc_probe);

-- 
2.39.5

Re: [PATCH v4 2/2] m68k: coldfire: Add RNG support for MCF54418

[Greg Ungerer]

Hi Jean-Michel,

On 26/11/25 17:08, Jean-Michel Hautbois via B4 Relay wrote:
> From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> 
> Add support for the hardware Random Number Generator (RNGB) found on
> MCF54418 ColdFire processors with clock enabled at platform
> initialization.
> 
> The RNGB block is compatible with the imx-rngc driver.
> 
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> ---
>   arch/m68k/coldfire/device.c       | 28 ++++++++++++++++++++++++++++
>   arch/m68k/coldfire/m5441x.c       |  2 +-
>   arch/m68k/include/asm/m5441xsim.h |  9 +++++++++
>   drivers/char/hw_random/Kconfig    |  3 ++-
>   drivers/char/hw_random/imx-rngc.c |  7 +++++++
>   5 files changed, 47 insertions(+), 2 deletions(-)

I am happy with the ColdFire arch parts, so from me:

     Acked-by: Greg Ungerer <gerg@linux-m68k.org>

I don't mind taking this commit via the m68knommu git tree if the hw_rng
maintainers are ok with that. Otherwise if you break out the arch/m68k
parts I can apply those on their own.

Regards
Greg



> diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
> index b6958ec2a220..9d8f844e319a 100644
> --- a/arch/m68k/coldfire/device.c
> +++ b/arch/m68k/coldfire/device.c
> @@ -622,6 +622,31 @@ static struct platform_device mcf_flexcan0 = {
>   };
>   #endif /* MCFFLEXCAN_SIZE */
>   
> +#ifdef MCF_RNG_BASE
> +/*
> + * Random Number Generator (RNG) - only on MCF54418
> + */
> +static struct resource mcf_rng_resource[] = {
> +	{
> +		.start = MCF_RNG_BASE,
> +		.end   = MCF_RNG_BASE + MCF_RNG_SIZE - 1,
> +		.flags = IORESOURCE_MEM,
> +	},
> +	{
> +		.start = MCF_IRQ_RNG,
> +		.end   = MCF_IRQ_RNG,
> +		.flags = IORESOURCE_IRQ,
> +	},
> +};
> +
> +static struct platform_device mcf_rng = {
> +	.name           = "imx-rngc",
> +	.id             = -1,
> +	.num_resources  = ARRAY_SIZE(mcf_rng_resource),
> +	.resource       = mcf_rng_resource,
> +};
> +#endif /* MCF_RNG_BASE */
> +
>   static struct platform_device *mcf_devices[] __initdata = {
>   	&mcf_uart,
>   #ifdef MCFFEC_BASE0
> @@ -660,6 +685,9 @@ static struct platform_device *mcf_devices[] __initdata = {
>   #ifdef MCFFLEXCAN_SIZE
>   	&mcf_flexcan0,
>   #endif
> +#ifdef MCF_RNG_BASE
> +	&mcf_rng,
> +#endif
>   };
>   
>   /*
> diff --git a/arch/m68k/coldfire/m5441x.c b/arch/m68k/coldfire/m5441x.c
> index 7a25cfc7ac07..ab5b00637237 100644
> --- a/arch/m68k/coldfire/m5441x.c
> +++ b/arch/m68k/coldfire/m5441x.c
> @@ -158,6 +158,7 @@ static struct clk * const enable_clks[] __initconst = {
>   	&__clk_0_33, /* pit.1 */
>   	&__clk_0_37, /* eport */
>   	&__clk_0_48, /* pll */
> +	&__clk_0_49, /* rng */
>   	&__clk_0_51, /* esdhc */
>   
>   	&__clk_1_36, /* CCM/reset module/Power management */
> @@ -179,7 +180,6 @@ static struct clk * const disable_clks[] __initconst = {
>   	&__clk_0_44, /* usb otg */
>   	&__clk_0_45, /* usb host */
>   	&__clk_0_47, /* ssi.0 */
> -	&__clk_0_49, /* rng */
>   	&__clk_0_50, /* ssi.1 */
>   	&__clk_0_53, /* enet-fec */
>   	&__clk_0_54, /* enet-fec */
> diff --git a/arch/m68k/include/asm/m5441xsim.h b/arch/m68k/include/asm/m5441xsim.h
> index f48cf63bd782..dd64cdfcad3e 100644
> --- a/arch/m68k/include/asm/m5441xsim.h
> +++ b/arch/m68k/include/asm/m5441xsim.h
> @@ -198,6 +198,15 @@
>   #define MCFRTC_SIZE		(0xfc0a8840 - 0xfc0a8000)
>   #define MCF_IRQ_RTC		(MCFINT2_VECBASE + MCFINT2_RTC)
>   
> +/*
> + *  Random Number Generator (RNG) Module.
> + *  Note: Only present in MCF54418, not in MCF54410/54415/54417
> + */
> +#define MCF_RNG_BASE		0xfc0c4000
> +#define MCF_RNG_SIZE		0x1c
> +#define MCFINT2_RNG		28
> +#define MCF_IRQ_RNG		(MCFINT2_VECBASE + MCFINT2_RNG)
> +
>   /*
>    *  GPIO Module.
>    */
> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
> index 492a2a61a65b..2f301e43db84 100644
> --- a/drivers/char/hw_random/Kconfig
> +++ b/drivers/char/hw_random/Kconfig
> @@ -270,12 +270,13 @@ config HW_RANDOM_MXC_RNGA
>   config HW_RANDOM_IMX_RNGC
>   	tristate "Freescale i.MX RNGC Random Number Generator"
>   	depends on HAS_IOMEM
> -	depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COMPILE_TEST
> +	depends on SOC_IMX25 || SOC_IMX6SL || SOC_IMX6SLL || SOC_IMX6UL || COLDFIRE || COMPILE_TEST
>   	default HW_RANDOM
>   	help
>   	  This driver provides kernel-side support for the Random Number
>   	  Generator Version C hardware found on some Freescale i.MX
>   	  processors. Version B is also supported by this driver.
> +	  Also supports RNGB on Freescale MCF54418 (Coldfire V4e).
>   
>   	  To compile this driver as a module, choose M here: the
>   	  module will be called imx-rngc.
> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> index d6a847e48339..44f20a05de0a 100644
> --- a/drivers/char/hw_random/imx-rngc.c
> +++ b/drivers/char/hw_random/imx-rngc.c
> @@ -353,12 +353,19 @@ static const struct of_device_id imx_rngc_dt_ids[] = {
>   };
>   MODULE_DEVICE_TABLE(of, imx_rngc_dt_ids);
>   
> +static const struct platform_device_id imx_rngc_devtype[] = {
> +	{ .name = "imx-rngc" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, imx_rngc_devtype);
> +
>   static struct platform_driver imx_rngc_driver = {
>   	.driver = {
>   		.name = KBUILD_MODNAME,
>   		.pm = pm_ptr(&imx_rngc_pm_ops),
>   		.of_match_table = imx_rngc_dt_ids,
>   	},
> +	.id_table = imx_rngc_devtype,
>   };
>   
>   module_platform_driver_probe(imx_rngc_driver, imx_rngc_probe);
>