Return-path: Received: from wf-out-1314.google.com ([209.85.200.171]:24222 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753067AbZBFIAa (ORCPT ); Fri, 6 Feb 2009 03:00:30 -0500 MIME-Version: 1.0 In-Reply-To: <386072610902052347m5754262bif18339809a00cb9f@mail.gmail.com> References: <1233819002-6912-1-git-send-email-cooloney@kernel.org> <1233846195.3028.14.camel@localhost> <386072610902052347m5754262bif18339809a00cb9f@mail.gmail.com> Date: Fri, 6 Feb 2009 16:00:28 +0800 Message-ID: <386072610902060000s2e150e4cla19aca70f38b0474@mail.gmail.com> (sfid-20090206_090038_249872_F960648B) Subject: Re: [PATCH] wireless: introduce POWEROF2_BLOCKSIZE_ONLY option From: Bryan Wu To: Dan Williams Cc: linville@tuxdriver.com, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Cliff Cai Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Feb 6, 2009 at 3:47 PM, Bryan Wu wrote: > On Thu, Feb 5, 2009 at 11:03 PM, Dan Williams wrote: >> On Thu, 2009-02-05 at 15:30 +0800, Bryan Wu wrote: >>> From: Cliff Cai >>> >>> Introduce POWEROF2_BLOCKSIZE_ONLY option for those SD/SDIO host >>> which only support transferring block with size of power-of-2 >> >> Is the point here to avoid copying in the controller code? As with the >> other patches on libertas-dev, I really dislike adding code to *every >> SDIO driver* just because the host has certain restrictions. I'd much >> rather that the host/controller code became aware of it's own >> restrictions, and exposed those generically to drivers above it. >> Without a KConfig option. >> >> Seriously. The host knows what it needs. The code to handle that >> should go in the host. >> > > I agree here. > >> How about adding a method like "sdio_align_size" that takes the >> controller's constraints into account? That seems a lot cleaner than >> adding #define/KConfig junk to every SDIO driver in the kernel. One >> less codepath to test, makes your life and all our lives easier. >> > > So we plan to add method ".sdio_align_size" to SDIO stack. > And Blackfin host driver will implement this method while others will > implement this as a dummy function. > sdio_align_size is already in SDIO stack, so we just need to add our constraints to this function. Thanks -Bryan > >>> [ Bryan Wu : >>> - remove some useless coding style cleanup >>> - using roundup() function as upstream does >>> ] >>> >>> Signed-off-by: Cliff Cai >>> Signed-off-by: Bryan Wu >>> --- >>> drivers/net/wireless/Kconfig | 6 ++++++ >>> drivers/net/wireless/libertas/if_sdio.c | 16 ++++++++++++++++ >>> 2 files changed, 22 insertions(+), 0 deletions(-) >>> >>> diff --git a/drivers/net/wireless/Kconfig b/drivers/net/wireless/Kconfig >>> index e4f9f74..a2685fa 100644 >>> --- a/drivers/net/wireless/Kconfig >>> +++ b/drivers/net/wireless/Kconfig >>> @@ -151,6 +151,12 @@ config LIBERTAS_SDIO >>> ---help--- >>> A driver for Marvell Libertas 8385 and 8686 SDIO devices. >>> >>> +config POWEROF2_BLOCKSIZE_ONLY >>> + bool "Support transferring block with size of power-of-2 only" >>> + depends on LIBERTAS_SDIO >>> + ---help--- >>> + For SD/SDIO host which only supports transferring block with size of power-of-2. >>> + >>> config LIBERTAS_DEBUG >>> bool "Enable full debugging output in the Libertas module." >>> depends on LIBERTAS >>> diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c >>> index 4519d73..5efc056 100644 >>> --- a/drivers/net/wireless/libertas/if_sdio.c >>> +++ b/drivers/net/wireless/libertas/if_sdio.c >>> @@ -272,6 +272,11 @@ static int if_sdio_card_to_host(struct if_sdio_card *card) >>> */ >>> chunk = sdio_align_size(card->func, size); >>> >>> +/* For SD/SDIO host which only supports transferring block with size of power-of-2 */ >>> +#if defined(CONFIG_POWEROF2_BLOCKSIZE_ONLY) >>> + chunk = (chunk + card->func->cur_blksize - 1) / >>> + card->func->cur_blksize * card->func->cur_blksize; >>> +#endif >>> ret = sdio_readsb(card->func, card->buffer, card->ioport, chunk); >>> if (ret) >>> goto out; >>> @@ -581,8 +586,14 @@ static int if_sdio_prog_real(struct if_sdio_card *card) >>> lbs_deb_sdio("sending %d bytes (%d bytes) chunk\n", >>> chunk_size, (chunk_size + 31) / 32 * 32); >>> */ >>> +/* For SD/SDIO host which only supports transferring block with size of power-of-2 */ >>> +#if defined(CONFIG_POWEROF2_BLOCKSIZE_ONLY) >>> + ret = sdio_writesb(card->func, card->ioport, >>> + chunk_buffer, roundup(chunk_size, 256); >>> +#else >>> ret = sdio_writesb(card->func, card->ioport, >>> chunk_buffer, roundup(chunk_size, 32)); >>> +#endif >>> if (ret) >>> goto release; >>> >>> @@ -699,6 +710,11 @@ static int if_sdio_host_to_card(struct lbs_private *priv, >>> */ >>> size = sdio_align_size(card->func, nb + 4); >>> >>> +/* For SD/SDIO host which only supports transferring block with size of power-of-2 */ >>> +#if defined(CONFIG_POWEROF2_BLOCKSIZE_ONLY) >>> + size = (size + card->func->cur_blksize - 1) / >>> + card->func->cur_blksize * card->func->cur_blksize; >>> +#endif >>> packet = kzalloc(sizeof(struct if_sdio_packet) + size, >>> GFP_ATOMIC); >>> if (!packet) { >> >> >