Re: [PATCH 11/12] hwrng: bcm2835-rng: Enable BCM2835 RNG to work on BCM63xx platforms

[Stefan Wahren]

> Florian Fainelli <f.fainelli@xxxxxxxxx> hat am 6. November 2017 um 21:16 geschrieben:
> 
> 
> On 11/04/2017 11:27 AM, Stefan Wahren wrote:
> > Hi Florian
> > 
> >> Florian Fainelli <f.fainelli@xxxxxxxxx> hat am 2. November 2017 um 02:04 geschrieben:
> >>
> >>
> >> We have now incorporated all necessary functionality for the BCM63xx
> >> platforms to successfully migrate over bcm2835-rng, so add the final
> >> bits: Kconfig selection and proper platform_device device type matching
> >> to keep the same platform device name for registration to work.
> >>
> >> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> >> ---
> >>  drivers/char/hw_random/Kconfig       |  7 ++++---
> >>  drivers/char/hw_random/bcm2835-rng.c | 11 ++++++++++-
> >>  2 files changed, 14 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
> >> index 95a031e9eced..d0689cc8c7fc 100644
> >> --- a/drivers/char/hw_random/Kconfig
> >> +++ b/drivers/char/hw_random/Kconfig
> >> @@ -87,12 +87,13 @@ config HW_RANDOM_BCM63XX
> >>  	  If unusure, say Y.
> >>  
> >>  config HW_RANDOM_BCM2835
> >> -	tristate "Broadcom BCM2835 Random Number Generator support"
> >> -	depends on ARCH_BCM2835 || ARCH_BCM_NSP || ARCH_BCM_5301X
> >> +	tristate "Broadcom BCM2835/BCM63xx Random Number Generator support"
> >> +	depends on ARCH_BCM2835 || ARCH_BCM_NSP || ARCH_BCM_5301X || \
> >> +		   ARCH_BCM_63XX || BCM63XX || BMIPS_GENERIC
> >>  	default HW_RANDOM
> >>  	---help---
> >>  	  This driver provides kernel-side support for the Random Number
> >> -	  Generator hardware found on the Broadcom BCM2835 SoCs.
> >> +	  Generator hardware found on the Broadcom BCM2835 and BCM63xx SoCs.
> >>  
> >>  	  To compile this driver as a module, choose M here: the
> >>  	  module will be called bcm2835-rng
> >> diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
> >> index 650e0033c273..d9ffe14f312b 100644
> >> --- a/drivers/char/hw_random/bcm2835-rng.c
> >> +++ b/drivers/char/hw_random/bcm2835-rng.c
> >> @@ -131,6 +131,7 @@ static const struct of_device_id bcm2835_rng_of_match[] = {
> >>  	{ .compatible = "brcm,bcm2835-rng"},
> >>  	{ .compatible = "brcm,bcm-nsp-rng", .data = &nsp_rng_of_data },
> >>  	{ .compatible = "brcm,bcm5301x-rng", .data = &nsp_rng_of_data },
> >> +	{ .compatible = "brcm,bcm6368-rng"},
> >>  	{},
> >>  };
> >>  
> >> @@ -164,7 +165,7 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
> >>  	if (IS_ERR(priv->clk))
> >>  		priv->clk = NULL;
> >>  
> >> -	priv->rng.name = "bcm2835-rng";
> >> +	priv->rng.name = pdev->id_entry->name;
> > 
> > this change breaks registration on bcm2835, because the name is NULL.
> 
> OH right, I will fix that in v2, I am assuming that if you did something
> like this, things still work correctly for you on 2835:
> 
> if (!priv->id_entry->name)
> 	priv->rng.name = "bcm2835-rng";
> else
> 	priv->rng.name = priv->id_entry->name;
> 
> ?

I think that should work, but i'm not really happy about it. I prefer a more general solution. Looking at the other rng drivers shows the following pattern:

priv->rng.name = pdev->name;

I need to verify this on bcm2835.

> 
> > 
> > Regards
> > Stefan
> > 
> >>  	priv->rng.init = bcm2835_rng_init;
> >>  	priv->rng.read = bcm2835_rng_read;
> >>  	priv->rng.cleanup = bcm2835_rng_cleanup;
> >> @@ -190,12 +191,20 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
> >>  
> >>  MODULE_DEVICE_TABLE(of, bcm2835_rng_of_match);
> >>  
> >> +static struct platform_device_id bcm2835_rng_devtype[] = {
> >> +	{ .name = "bcm2835-rng" },
> >> +	{ .name = "bcm63xx-rng" },
> >> +	{ /* sentinel */ }
> >> +};
> >> +MODULE_DEVICE_TABLE(platform, bcm2835_rng_devtype);
> >> +
> >>  static struct platform_driver bcm2835_rng_driver = {
> >>  	.driver = {
> >>  		.name = "bcm2835-rng",
> >>  		.of_match_table = bcm2835_rng_of_match,
> >>  	},
> >>  	.probe		= bcm2835_rng_probe,
> >> +	.id_table	= bcm2835_rng_devtype,
> >>  };
> >>  module_platform_driver(bcm2835_rng_driver);
> >>  
> >> -- 
> >> 2.9.3
> >>
> >>
> >> _______________________________________________
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> 
> 
> -- 
> Florian
> 
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