From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH] i2c: at91: fix support of the "alternative command" feature Date: Mon, 15 Aug 2016 00:34:37 +0200 Message-ID: <20160814223437.GG10501@katana> References: <20160803145826.11927-1-ludovic.desroches@atmel.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="0qt3EE9wi45a2ZFX" Return-path: Content-Disposition: inline In-Reply-To: <20160803145826.11927-1-ludovic.desroches@atmel.com> Sender: linux-kernel-owner@vger.kernel.org To: Ludovic Desroches Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, nicolas.ferre@atmel.com, linux-arm-kernel@lists.infradead.org, Cyrille Pitchen List-Id: linux-i2c@vger.kernel.org --0qt3EE9wi45a2ZFX Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Aug 03, 2016 at 04:58:26PM +0200, Ludovic Desroches wrote: > From: Cyrille Pitchen >=20 > The "alternative command" feature was introduced with sama5d2 SoCs. >=20 > Its purpose is to let the hardware i2c controller automatically send the > STOP condition on the i2c bus at the end of a data transfer. > Without this feature, the i2c driver has to write the 'STOP' bit into the > Control Register so the hardware i2c controller is triggered to send the > STOP condition on the bus. >=20 > Using the "alternative command" feature requires to set the transfer data > length into the 8bit DATAL field of the Alternative Command Register. > Hence only data transfers up to 255 bytes can take advantage of the > "alternative command" feature. For greater data transfer sizes, the driver > should use the previous implementation, when the "alternative command" > support was not implemented yet. >=20 > Signed-off-by: Cyrille Pitchen > Signed-off-by: Ludovic Desroches Applied to for-current, thanks! --0qt3EE9wi45a2ZFX Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXsPH9AAoJEBQN5MwUoCm20OIP/0C8qmkN4DTS/wvozM/VlgQo Rz/2wm3eDI6SK8qF6UChN4tp7qStV0Zkf4SwoCIS9iHdJ34kv3B64vaXTcS/jih7 xnBj5HLqV5DH8Y6dMRda+esAguFS4QRl3gDtKvYn6JdfFmGxyM8a8g78tnKGHZgD LG69dykJnLRz0C29jRaaTyo1VCgION3dn2u7xo/6RSYGDzMf1DYt21Sy7mWkuvEJ +oIHcExxJDjdKfvYZKpjItn9pCNPuEJSwwMV1tLRcRJX9Uf1eiNA+xNaBFHvQgbf 9hPvpkfJ6lmOYkDITE4ozBEooRux/8lAIfEs3xn55fewgQHACt10swW8QOi1YrgB r77TT4d3I0I+yoe1GaarAuNjxY33AuVqOEiO6lc0yYIuzCu2h/BDHvVkOy0vZpRY LkQx9pC7hkEXhAON3tyl73G4ChjKX/1I1a8tl4Bndyov4FwQCHRTXHqBfpN1fMSZ Kdoe5HB086JdvydF6d9GrLCK8rv/VET8oljxnMcQQanTEVadjbaaCxtzeBEbDQ9B C2wLdiusnKyWdUAtvwI8nqGeF1uGBTbYk9/F/xxhV+6ZYFStUVcaCNPW1yoQ7Vr0 +wusfZIad/FNR9Bf8z7QCKj12QFqO9BluV4ZWFaIOrnLLifT79rIGIZhgkbnEopl BSuB7ViI6NNl+6wZ9Pz/ =9yGF -----END PGP SIGNATURE----- --0qt3EE9wi45a2ZFX--