From patchwork Wed Jul 17 11:58:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Noralf_Tr=C3=B8nnes?= X-Patchwork-Id: 11047769 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D38931398 for ; Wed, 17 Jul 2019 11:58:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C3A7B22376 for ; Wed, 17 Jul 2019 11:58:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B829722B39; Wed, 17 Jul 2019 11:58:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4F87622376 for ; Wed, 17 Jul 2019 11:58:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1BA066E13C; Wed, 17 Jul 2019 11:58:33 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from smtp.domeneshop.no (smtp.domeneshop.no [IPv6:2a01:5b40:0:3005::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 26C5D6E122 for ; Wed, 17 Jul 2019 11:58:32 +0000 (UTC) Received: from 211.81-166-168.customer.lyse.net ([81.166.168.211]:54758 helo=localhost.localdomain) by smtp.domeneshop.no with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.84_2) (envelope-from ) id 1hniZq-0007Eh-8D; Wed, 17 Jul 2019 13:58:30 +0200 From: =?utf-8?q?Noralf_Tr=C3=B8nnes?= To: dri-devel@lists.freedesktop.org Subject: [PATCH 04/10] drm/tinydrm: Remove tinydrm_spi_max_transfer_size() Date: Wed, 17 Jul 2019 13:58:11 +0200 Message-Id: <20190717115817.30110-5-noralf@tronnes.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190717115817.30110-1-noralf@tronnes.org> References: <20190717115817.30110-1-noralf@tronnes.org> MIME-Version: 1.0 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tronnes.org; s=ds201810; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=tZNA509fZ5sgx0p5oZi7L7CD2nAKbBJobYHrtj54HWI=; b=VnfC/xrFqu6F1SbDU7VvkmilALBP+4dVIYbBW45YVgOkBrNFB3m9W1+NW3DDvEJYZ8cOz+eCYmxZMvUpPtca8rFKN5Acqr4S5Rw5BOWmE8ogixhAtkvI6HjlyLbktUYiFWexH1E0vKbvvlQugdokeuG7U1n1p/bxCAcsfidFlE4VOoixisjbkOipcfH72gihmuc0N3TZ7RUMGHDnjCRor29yQlRULbtOduS2z1Wz+yYFAKIjG+TJBuudfGCayjvVjCiy0TjsINo8BcjR1kVN9ZkdjGEHHt6XaBch+MnWZZRgdV1DrMaOByJGn7N0tMUTVPAQUSvNP5MRXw9Qd36hpQ==; X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: david@lechnology.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP spi-bcm2835 can handle >64kB buffers now so there is no need to check ->max_dma_len. The tinydrm_spi_max_transfer_size() max_len argument is not used by any callers, so not needed. Then we have the spi_max module parameter. It was added because staging/fbtft has support for it and there was a report that someone used it to set a small buffer size to avoid popping on a USB soundcard on a Raspberry Pi. In hindsight it shouldn't have been added, I should have waited for it to become a problem first. I don't know it anyone is actually using it, but since tinydrm_spi_transfer() is being moved to mipi-dbi, I'm taking the opportunity to remove it. I'll add it back to mipi-dbi if someone complains. With that out of the way, spi_max_transfer_size() can be used instead. The chosen 16kB buffer size for Type C Option 1 (9-bit) interface is somewhat arbitrary, but a bigger buffer will have a miniscule impact on transfer speed, so it's probably fine. Signed-off-by: Noralf Trønnes --- .../gpu/drm/tinydrm/core/tinydrm-helpers.c | 37 +------------------ drivers/gpu/drm/tinydrm/mipi-dbi.c | 10 +---- include/drm/tinydrm/tinydrm-helpers.h | 1 - 3 files changed, 3 insertions(+), 45 deletions(-) diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c index 272616a246cd..af5bec8861de 100644 --- a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c +++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c @@ -18,41 +18,8 @@ #include #include -static unsigned int spi_max; -module_param(spi_max, uint, 0400); -MODULE_PARM_DESC(spi_max, "Set a lower SPI max transfer size"); - #if IS_ENABLED(CONFIG_SPI) -/** - * tinydrm_spi_max_transfer_size - Determine max SPI transfer size - * @spi: SPI device - * @max_len: Maximum buffer size needed (optional) - * - * This function returns the maximum size to use for SPI transfers. It checks - * the SPI master, the optional @max_len and the module parameter spi_max and - * returns the smallest. - * - * Returns: - * Maximum size for SPI transfers - */ -size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len) -{ - size_t ret; - - ret = min(spi_max_transfer_size(spi), spi->master->max_dma_len); - if (max_len) - ret = min(ret, max_len); - if (spi_max) - ret = min_t(size_t, ret, spi_max); - ret &= ~0x3; - if (ret < 4) - ret = 4; - - return ret; -} -EXPORT_SYMBOL(tinydrm_spi_max_transfer_size); - /** * tinydrm_spi_transfer - SPI transfer helper * @spi: SPI device @@ -75,21 +42,19 @@ int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz, struct spi_transfer *header, u8 bpw, const void *buf, size_t len) { + size_t max_chunk = spi_max_transfer_size(spi); struct spi_transfer tr = { .bits_per_word = bpw, .speed_hz = speed_hz, }; struct spi_message m; u16 *swap_buf = NULL; - size_t max_chunk; size_t chunk; int ret = 0; if (WARN_ON_ONCE(bpw != 8 && bpw != 16)) return -EINVAL; - max_chunk = tinydrm_spi_max_transfer_size(spi, 0); - if (bpw == 16 && !spi_is_bpw_supported(spi, 16)) { tr.bits_per_word = 8; if (tinydrm_machine_little_endian()) { diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c index 99509d16b037..ae31a5c9aa1b 100644 --- a/drivers/gpu/drm/tinydrm/mipi-dbi.c +++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c @@ -964,15 +964,9 @@ static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 *cmd, int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi, struct gpio_desc *dc) { - size_t tx_size = tinydrm_spi_max_transfer_size(spi, 0); struct device *dev = &spi->dev; int ret; - if (tx_size < 16) { - DRM_ERROR("SPI transmit buffer too small: %zu\n", tx_size); - return -EINVAL; - } - /* * Even though it's not the SPI device that does DMA (the master does), * the dma mask is necessary for the dma_alloc_wc() in @@ -1001,8 +995,8 @@ int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi, mipi->swap_bytes = true; } else { mipi->command = mipi_dbi_typec1_command; - mipi->tx_buf9_len = tx_size; - mipi->tx_buf9 = devm_kmalloc(dev, tx_size, GFP_KERNEL); + mipi->tx_buf9_len = SZ_16K; + mipi->tx_buf9 = devm_kmalloc(dev, mipi->tx_buf9_len, GFP_KERNEL); if (!mipi->tx_buf9) return -ENOMEM; } diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h index dca75de3a359..10b35375a009 100644 --- a/include/drm/tinydrm/tinydrm-helpers.h +++ b/include/drm/tinydrm/tinydrm-helpers.h @@ -41,7 +41,6 @@ int tinydrm_display_pipe_init(struct drm_device *drm, const struct drm_display_mode *mode, unsigned int rotation); -size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len); int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz, struct spi_transfer *header, u8 bpw, const void *buf, size_t len);