[PATCH v2] davinci: da850 EVM: read mac address from SPI flash

[PATCH v2] davinci: da850 EVM: read mac address from SPI flash

[Rajashekhara, Sudhakar]

DA850/OMAP-L138 EMAC driver uses random mac address instead of
a fixed one because the mac address is not stuffed into EMAC
platform data.

This patch provides a function which reads the mac address
stored in SPI flash (registered as MTD device) and populates the
EMAC platform data. The function which reads the mac address is
registered as a callback which gets called upon addition of MTD
device.

NOTE: In case the MAC address stored in SPI flash is erased, follow
the instructions at [1] to restore it.

[1] http://processors.wiki.ti.com/index.php/GSG:_OMAP-L138_DVEVM_Additional_Procedures#Restoring_MAC_address_on_SPI_Flash

Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com>
---
Since v1:
     Guarded registering the mtd_notifier only when MTD is enabled.
     Earlier this was handled using mtd_has_partitions() call, but
     this has been removed in Linux v3.0.

 arch/arm/mach-davinci/board-da850-evm.c |   28 ++++++++++++++++++++++++++++
 1 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-davinci/board-da850-evm.c b/arch/arm/mach-davinci/board-da850-evm.c
index a7b41bf..f994a1f 100644
--- a/arch/arm/mach-davinci/board-da850-evm.c
+++ b/arch/arm/mach-davinci/board-da850-evm.c
@@ -115,6 +115,23 @@ static struct spi_board_info da850evm_spi_info[] = {
 	},
 };
 
+static void da850_evm_m25p80_notify_add(struct mtd_info *mtd)
+{
+	char *mac_addr = davinci_soc_info.emac_pdata->mac_addr;
+	size_t retlen;
+
+	if (!strcmp(mtd->name, "MAC-Address")) {
+		mtd->read(mtd, 0, ETH_ALEN, &retlen, mac_addr);
+		if (retlen == ETH_ALEN)
+			pr_info("Read MAC addr from SPI Flash: %pM\n",
+				mac_addr);
+	}
+}
+
+static struct mtd_notifier da850evm_spi_notifier = {
+	.add	= da850_evm_m25p80_notify_add,
+};
+
 static struct mtd_partition da850_evm_norflash_partition[] = {
 	{
 		.name           = "bootloaders + env",
@@ -1117,6 +1134,15 @@ static __init int da850_evm_init_cpufreq(void)
 static __init int da850_evm_init_cpufreq(void) { return 0; }
 #endif
 
+#ifdef CONFIG_MTD
+static void da850_evm_register_mtd_user(struct mtd_notifier *notify)
+{
+	register_mtd_user(notify);
+}
+#else
+static void da850_evm_register_mtd_user(struct mtd_notifier *notify) { }
+#endif
+
 static __init void da850_evm_init(void)
 {
 	int ret;
@@ -1237,6 +1263,8 @@ static __init void da850_evm_init(void)
 	if (ret)
 		pr_warning("da850_evm_init: spi 1 registration failed: %d\n",
 				ret);
+
+	da850_evm_register_mtd_user(&da850evm_spi_notifier);
 }
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
-- 
1.7.1

[PATCH v2] davinci: da850 EVM: read mac address from SPI flash

[Nori, Sekhar]

Hi Sudhakar,

On Mon, Jul 04, 2011 at 18:37:18, Rajashekhara, Sudhakar wrote:
> DA850/OMAP-L138 EMAC driver uses random mac address instead of
> a fixed one because the mac address is not stuffed into EMAC
> platform data.
> 
> This patch provides a function which reads the mac address
> stored in SPI flash (registered as MTD device) and populates the
> EMAC platform data. The function which reads the mac address is
> registered as a callback which gets called upon addition of MTD
> device.
> 
> NOTE: In case the MAC address stored in SPI flash is erased, follow
> the instructions at [1] to restore it.
> 
> [1] http://processors.wiki.ti.com/index.php/GSG:_OMAP-L138_DVEVM_Additional_Procedures#Restoring_MAC_address_on_SPI_Flash
> 
> Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com>
> ---
> Since v1:
>      Guarded registering the mtd_notifier only when MTD is enabled.
>      Earlier this was handled using mtd_has_partitions() call, but
>      this has been removed in Linux v3.0.

Current trend is to include the change log into the
commit message itself. It might be useful to examine
at a later time what transformation the patch went
through. It also simplifies things for you since you
don't have to maintain this separately.

> +static void da850_evm_m25p80_notify_add(struct mtd_info *mtd)
> +{
> +	char *mac_addr = davinci_soc_info.emac_pdata->mac_addr;
> +	size_t retlen;
> +
> +	if (!strcmp(mtd->name, "MAC-Address")) {
> +		mtd->read(mtd, 0, ETH_ALEN, &retlen, mac_addr);
> +		if (retlen == ETH_ALEN)
> +			pr_info("Read MAC addr from SPI Flash: %pM\n",
> +				mac_addr);
> +	}
> +}
> +
> +static struct mtd_notifier da850evm_spi_notifier = {
> +	.add	= da850_evm_m25p80_notify_add,
> +};

The function and data structure above are not required
when CONFIG_MTD is not defined so these should be
under #ifdef CONFIG_MTD too. Towards this..

> +#ifdef CONFIG_MTD
> +static void da850_evm_register_mtd_user(struct mtd_notifier *notify)
> +{
> +	register_mtd_user(notify);
> +}

.. rename this function as something like da850_evm_setup_mac_addr() and
make it take void as argument and use:

	register_mtd_user(&da850evm_spi_notifier);

Thanks,
Sekhar

> +#else
> +static void da850_evm_register_mtd_user(struct mtd_notifier *notify) { }
> +#endif
> +
>  static __init void da850_evm_init(void)
>  {
>  	int ret;
> @@ -1237,6 +1263,8 @@ static __init void da850_evm_init(void)
>  	if (ret)
>  		pr_warning("da850_evm_init: spi 1 registration failed: %d\n",
>  				ret);
> +
> +	da850_evm_register_mtd_user(&da850evm_spi_notifier);
>  }
>  
>  #ifdef CONFIG_SERIAL_8250_CONSOLE
> -- 
> 1.7.1
> 
> _______________________________________________
> Davinci-linux-open-source mailing list
> Davinci-linux-open-source at linux.davincidsp.com
> http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
> 

[PATCH v2] davinci: da850 EVM: read mac address from SPI flash

[Rajashekhara, Sudhakar]

Hi Sekhar,

On Wed, Jul 06, 2011 at 21:22:52, Nori, Sekhar wrote:
> Hi Sudhakar,
> 
> On Mon, Jul 04, 2011 at 18:37:18, Rajashekhara, Sudhakar wrote:
> > DA850/OMAP-L138 EMAC driver uses random mac address instead of
> > a fixed one because the mac address is not stuffed into EMAC
> > platform data.
> > 
> > This patch provides a function which reads the mac address
> > stored in SPI flash (registered as MTD device) and populates the
> > EMAC platform data. The function which reads the mac address is
> > registered as a callback which gets called upon addition of MTD
> > device.
> > 
> > NOTE: In case the MAC address stored in SPI flash is erased, follow
> > the instructions at [1] to restore it.
> > 
> > [1] http://processors.wiki.ti.com/index.php/GSG:_OMAP-L138_DVEVM_Additional_Procedures#Restoring_MAC_address_on_SPI_Flash
> > 
> > Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com>
> > ---
> > Since v1:
> >      Guarded registering the mtd_notifier only when MTD is enabled.
> >      Earlier this was handled using mtd_has_partitions() call, but
> >      this has been removed in Linux v3.0.
> 
> Current trend is to include the change log into the
> commit message itself. It might be useful to examine
> at a later time what transformation the patch went
> through. It also simplifies things for you since you
> don't have to maintain this separately.
> 

You are right, this is very helpful. I'll move the change log into the commit message.

> > +static void da850_evm_m25p80_notify_add(struct mtd_info *mtd)
> > +{
> > +	char *mac_addr = davinci_soc_info.emac_pdata->mac_addr;
> > +	size_t retlen;
> > +
> > +	if (!strcmp(mtd->name, "MAC-Address")) {
> > +		mtd->read(mtd, 0, ETH_ALEN, &retlen, mac_addr);
> > +		if (retlen == ETH_ALEN)
> > +			pr_info("Read MAC addr from SPI Flash: %pM\n",
> > +				mac_addr);
> > +	}
> > +}
> > +
> > +static struct mtd_notifier da850evm_spi_notifier = {
> > +	.add	= da850_evm_m25p80_notify_add,
> > +};
> 
> The function and data structure above are not required
> when CONFIG_MTD is not defined so these should be
> under #ifdef CONFIG_MTD too. Towards this..
> 

Ok.

> > +#ifdef CONFIG_MTD
> > +static void da850_evm_register_mtd_user(struct mtd_notifier *notify)
> > +{
> > +	register_mtd_user(notify);
> > +}
> 
> .. rename this function as something like da850_evm_setup_mac_addr() and
> make it take void as argument and use:
> 
> 	register_mtd_user(&da850evm_spi_notifier);
> 

Agreed. I'll include these modifications and send the updated version.

Thanks,
Sudhakar