LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
To: Andrew Lunn <andrew@lunn.ch>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Vivien Didelot <vivien.didelot@gmail.com>
Subject: Re: [RFC PATCH 1/5] net: dsa: mv88e6xxx: introduce support for two chips using direct smi addressing
Date: Wed, 8 May 2019 07:57:38 +0000	[thread overview]
Message-ID: <f5924091-352c-c14a-f959-6bb8a32746e3@prevas.dk> (raw)
In-Reply-To: <20190501201919.GC19809@lunn.ch>

On 01/05/2019 22.19, Andrew Lunn wrote:
> On Wed, May 01, 2019 at 07:32:10PM +0000, Rasmus Villemoes wrote:
>> The 88e6250 (as well as 6220, 6071, 6070, 6020) do not support
>> multi-chip (indirect) addressing. However, one can still have two of
>> them on the same mdio bus, since the device only uses 16 of the 32
>> possible addresses, either addresses 0x00-0x0F or 0x10-0x1F depending
>> on the ADDR4 pin at reset [since ADDR4 is internally pulled high, the
>> latter is the default].
>>
>> In order to prepare for supporting the 88e6250 and friends, introduce
>> mv88e6xxx_info::dual_chip to allow having a non-zero sw_addr while
>> still using direct addressing.
>>
>> Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
>> ---
>>  drivers/net/dsa/mv88e6xxx/chip.c | 10 +++++++---
>>  drivers/net/dsa/mv88e6xxx/chip.h |  5 +++++
>>  2 files changed, 12 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
>> index c078c791f481..f66daa77774b 100644
>> --- a/drivers/net/dsa/mv88e6xxx/chip.c
>> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
>> @@ -62,6 +62,10 @@ static void assert_reg_lock(struct mv88e6xxx_chip *chip)
>>   * When ADDR is non-zero, the chip uses Multi-chip Addressing Mode, allowing
>>   * multiple devices to share the SMI interface. In this mode it responds to only
>>   * 2 registers, used to indirectly access the internal SMI devices.
>> + *
>> + * Some chips use a different scheme: Only the ADDR4 pin is used for
>> + * configuration, and the device responds to 16 of the 32 SMI
>> + * addresses, allowing two to coexist on the same SMI interface.
>>   */
>>  
>>  static int mv88e6xxx_smi_read(struct mv88e6xxx_chip *chip,
>> @@ -87,7 +91,7 @@ static int mv88e6xxx_smi_single_chip_read(struct mv88e6xxx_chip *chip,
>>  {
>>  	int ret;
>>  
>> -	ret = mdiobus_read_nested(chip->bus, addr, reg);
>> +	ret = mdiobus_read_nested(chip->bus, addr + chip->sw_addr, reg);
>>  	if (ret < 0)
>>  		return ret;
>>  
>> @@ -101,7 +105,7 @@ static int mv88e6xxx_smi_single_chip_write(struct mv88e6xxx_chip *chip,
>>  {
>>  	int ret;
>>  
>> -	ret = mdiobus_write_nested(chip->bus, addr, reg, val);
>> +	ret = mdiobus_write_nested(chip->bus, addr + chip->sw_addr, reg, val);
>>  	if (ret < 0)
>>  		return ret;
> 
> Hi Rasmus
> 
> This works, but i think i prefer adding mv88e6xxx_smi_dual_chip_write,
> mv88e6xxx_smi_dual_chip_read, and create a
> mv88e6xxx_smi_single_chip_ops.

Hi Andrew

Now that Vivien's "net: dsa: mv88e6xxx: refine SMI support" is in
master, do you still prefer introducing a third bus_ops structure
(mv88e6xxx_smi_dual_direct_ops ?), or would the approach of adding
chip->sw_addr in the smi_direct_{read/write} functions be ok (which
would then require changing the indirect callers to pass 0 instead of
chip->swaddr).

Thanks,
Rasmus

  reply	other threads:[~2019-05-08  7:57 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-01 19:32 [RFC PATCH 0/5] net: dsa: POC support for mv88e6250 Rasmus Villemoes
2019-05-01 19:32 ` [RFC PATCH 1/5] net: dsa: mv88e6xxx: introduce support for two chips using direct smi addressing Rasmus Villemoes
2019-05-01 20:19   ` Andrew Lunn
2019-05-08  7:57     ` Rasmus Villemoes [this message]
2019-05-08 11:47       ` Andrew Lunn
2019-05-08 13:41         ` Vivien Didelot
2019-05-01 19:32 ` [RFC PATCH 2/5] net: dsa: mv88e6xxx: rename smi read/write functions Rasmus Villemoes
2019-05-03 21:57   ` Vivien Didelot
2019-05-06  5:57     ` Rasmus Villemoes
2019-05-06 14:51       ` Vivien Didelot
2019-05-01 19:32 ` [RFC PATCH 3/5] net: dsa: prepare mv88e6xxx_g1_atu_op() for the mv88e6250 Rasmus Villemoes
2019-05-01 20:22   ` Andrew Lunn
2019-05-01 19:32 ` [RFC PATCH 4/5] net: dsa: implement vtu_getnext and vtu_loadpurge for mv88e6250 Rasmus Villemoes
2019-05-01 20:25   ` Andrew Lunn
2019-05-01 19:32 ` [RFC PATCH 5/5] net: dsa: add support " Rasmus Villemoes
2019-05-01 20:29   ` Andrew Lunn
2019-05-24  9:00 ` [PATCH v2 0/5] net: dsa: " Rasmus Villemoes
2019-05-24  9:00   ` [PATCH v2 1/5] net: dsa: mv88e6xxx: introduce support for two chips using direct smi addressing Rasmus Villemoes
2019-05-24 14:13     ` Andrew Lunn
2019-05-24 17:54     ` Vivien Didelot
2019-05-24  9:00   ` [PATCH v2 2/5] net: dsa: prepare mv88e6xxx_g1_atu_op() for the mv88e6250 Rasmus Villemoes
2019-05-24 17:57     ` Vivien Didelot
2019-05-24  9:00   ` [PATCH v2 3/5] net: dsa: implement vtu_getnext and vtu_loadpurge for mv88e6250 Rasmus Villemoes
2019-05-24 18:02     ` Vivien Didelot
2019-05-24  9:00   ` [PATCH v2 4/5] net: dsa: mv88e6xxx: implement watchdog_ops " Rasmus Villemoes
2019-05-24 14:20     ` Andrew Lunn
2019-05-24 18:05     ` Vivien Didelot
2019-05-24  9:00   ` [PATCH v2 5/5] net: dsa: add support " Rasmus Villemoes
2019-05-24 14:27     ` Andrew Lunn
2019-06-03  8:52       ` Rasmus Villemoes
2019-06-03 12:45         ` Andrew Lunn
2019-05-24 18:11     ` Vivien Didelot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=f5924091-352c-c14a-f959-6bb8a32746e3@prevas.dk \
    --to=rasmus.villemoes@prevas.dk \
    --cc=andrew@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=f.fainelli@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=vivien.didelot@gmail.com \
    --subject='Re: [RFC PATCH 1/5] net: dsa: mv88e6xxx: introduce support for two chips using direct smi addressing' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).